mid 60's b bodies ( 330/sport fury/satellite/etc)

what coil over spring rates are you guys usually using on 34- 3500 hundred lbs cars that are running 10.0 or so?

I will 4 corner weight thus one next week and then call Strange /Comp etc to get their data but would like to hear from others.

My research says- lightest spring we can run without coil binding and then tune spring control return from compression with shock ( duh), tire hit with front location of ladder bar.

I know manufactures are going to give me data based on 4 corner weights, what else do we need to factor in?

Are some of you using staggered spring rates?
Staggered shock settings?
How much front end travel do you like to see before hitting the limiters?

Personally - it seems to me the faster we can get the hit to move the car forward- the better- hello!, thus too much time spent with suspension movement is counter productive as well.
right now this car has zero- nada rear of car compression.
I filmed it and have studied it to death, i don't believe the springs compressed a 1/2 inch.
Shock travel appears to be very little as well.
My hypotheses is simply the suspension isnt working and thus the tire spin on launch and second gear.
I think rear springs are 200 lbs .
Can i depend on Strange data sets based on 4 corner weights of car with driver in it, fuel cell full and tune from there?

Back in the good ole days ( grin ) we just made the rear stiff as we could and put 90/10"s up front, but we didn't go as fast as you guys are today either- grin.

Thanks guys.

Ladder bars tend to add stiffness to the suspension and keep the car from rotating the front end. Maybe it's just because they also act as an anti roll bar, but I have set up multiple cars where the car seems to be less active on launch, even though it bites harder. 200 sounds about right for the weight, but if you can swing it, it's never a bad idea to experiment with +/- pressure springs. Just like playing with shock settings. No reason to stagger spring rates. If it's necessary, then something is wrong in the car or suspension. I had problems with tire spin on shifts. It ends up my tires went away. Would still launch fine, but I have videos of tire smoke on gear changes.

The lighter the better. My 63/64 B Bodys have been 120-130 on the rear. You need a rate that puts the shock in the correct range of travel. That would be in the the middle or slightly compressed. These rates will do that. Track only you might even get away with 110, but it would be tight on compression travel. My Belvedere ran a string of 1.25-1.26 last Saturday foot braking on 10.5x31.
Doug

DVW: Would you mind sharing a little more data on car?
HP/TQ
727?
Stall?

This car is 675 hp at flywheel 511 stroker.
5400 stall
727 Rollerized- build, bolt in sprag etc
Race only car.

only 60 footing 146-148
weight transfer is basically non-existent
90/10 front shocks/travel limiters.

Its my opinion the 200 lbs are just too tight for the car and thats why there isn't any rear travel to help plant the car i don't think the shocks get a chance to do blooming thing.
Ladder bars were set in center hole ( neutral )
I would like to see some compression and the shock controlling rebound long enough to carry the car on the tire so it stays planted.
just my thoughts.
Am i nuts?

I have never ran more than 140lbs springs on a b-body with ladder bars - like Doug said 120-130 is usually about right for keeping the shock in the middle of it's range. Depending on the body style hard top or post the bias will be different - hardtops usually will carry more weight up front

Never been on a dyno. Best ever 9.00@150@3340lbs.572, guessing 900+, 727, 6100 flash. A 200 lb in my opinion is way to stiff. Rear will have very little help with rear seperation as the springs are barely compressed at ride height. Be aware power affects 60 ft. My bet is your combo has at least .05-.10 left in 60ft. Once the rear is scienced out chances are the 90/10 will be too loose. Just had my front Afco doubles tightened about 50%
Doug

What size torsion bars and what ride height in the front now? How much front end travel before the suspension limiters work?
I would lower the torsion bars to the bottom hole and see how much that helps your sixty foot times
My old ladder bar coil over Duster(3450Lbs. with me in it) started out with 175 lbs. springs, I switched to a set 150 and that helped, I should have tried a set of 130 Lbs. but I didn't
On your deal not knowing on how much weight is on the front and rear I would probably try a set of 140 Lbs. springs next

Its not my car, just one we are helping to get where it needs to be.
Agreed on front shocks- needs adjustable's.

Im thinking it should 60 ft in the mid to high 1.30's if car is right.
Im also wondering is his tires are toast even though wear indicators show tires to still be good.
My reasoning here is they are several seasons old and breaking loose pretty hard in second, wondering if age has just hardened the compound.

I will get 4 corner weights next week, make some phone calls and may reach out to you as well if you don't mind.

I'm going to assume 3400# with maybe 54% on the nose. That's about 1550 on the rear.

What shock/spring combination is on this? If it's a typical 17" extended length shock, like a 3850 AFCO, or S5206 or S5006 Strange with a 12" spring, a 200# spring has to be holding that shock at full or almost full extended length. It's can't separate without topping the shock. Plus it has to about as stiff as a solid suspension.

So, the shock installed length needs to be correct, about 13 3/4" or so. I would try a 150 if my assumptions are correct. This spring will need to be compressed a bit to hold the shock at the correct length @ ride height. Then a good shock can be used to control the separation at the hit. With that horsepower level, it won't need a lot of separation. You don't want to crush the tire.

90/10s are probably not the best choice for this car. A good adjustable shock, so you can control separation, with a bit smaller than stock torsion bar is where I would start.

Again, this is all based on assumption of what's under that car.

Cm: Thanks.
Stock front suspension other than wilwood drag brakes
I would like to see lighter torsion bars and two way adjustable shocks as well.

ladder bars and coil overs in rear- no leaf springs.
8.75 braced, 4.30 gear/spool

Car went 9.80"s on the bottle with cal-tracs - no issues when stock stroked, stroked it and its torn up everything from tranny to driveshafts to rear end housing - made a horseshoe out of it.

Im trying to help him get car sorted as he had ladder bars, coil over installed.

we did an chassis dyno at end of season last year and then took engine to engine dyno- huge chassis loss showed up.
New converter based on dyno info , chassis was twisted- put it on a chassis table and had that straightened out, stiffened chassis.

went to test and tune and, car doesn't want to hook, i shot video of the pulls he got before throwing the shaft out - u-joint clamp failure.

rear of chassis has zero movement , front try's to come up but, tire unloads , cant hold separation /rotation.
My guess is you are correct- too much spring, shock cannot work.
rear of car didn't move up or down- locked out like rear is welded to chassis.
Tire bits, lets go, bites, lets go- porpoising the car.

we just had through tranny- it was fine, i then found the tail-shaft bushing was bad, had that changed , sent converter to be checked and should have it back this week and we can get 4 corner weights then.

The rear shocks are probably topping out and unloading the rear. Lighter spring's and set the shocks up to the manufacturer's ride height.
Mines a e-body that weighs 3490 and I'm using 130 qa1. Different brands have different rates too. Strange 110's work on my car too.

a correction CM: He does have lighter spring tension torsion bars , runs travel limiters.

1. I think the 90/10's are worn smooth out- people forget they are still in use on the trailer so, however many miles one travels to races- suspension has that many miles on it too.

2. Ladder bar front point has 4 holes, he is in second from bottom.

3. Agreed, I think shock is topped out.

4. I think corner weights are going to show a max spring rate of 150, i'm thinking 130 will probably be correct.
My understanding is to use the lightest spring you can without coil bind and use a good shock- is this correct/factual?

Thanks

Im going to weight it next week Cab.
Im thinking 130-140 is going to be correct.
I have the empty weights- just driver in car, no engine/tranny/fluids and i know what those weigh, but not the distribution factors.

Im thinking the ladder bars need to be on bottom hole or 1 up.
New adjustable front shocks and the right rear springs/shock settings.

We get it close we can start playing with tire pressures vs shock settings front and rear.

i really wish i was able to get driveshaft speed readings and g forces would be really cool as well for chassis tuning- even on these old cars .
being able to see the results of "fine" adjustments would be really cool as well as beneficial.

just my thoughts

Correct shock installed length at ride height and good shocks on a ladder bar car with some power are critical. Without those, nothing else matters.

I agree fix this issue and try it. It may not need anything else.

Ok Guys, I 4 cornered the car this evening :

3363 with driver and all fluids.

50.7 percent of weight on drivers side.

47.0 percent on rear of car

LF - 973
RF- 809
LR- 737
RR- 845

Car was pretty well level.

Ladder bars:
Drivers side down in front 2 degrees.
Passenger side was dead level

Checked rear for square to car and it’s out 1/16 inch .

Current springs compressed almost an inch , shocks being held almost fully open .

What springs rate would you reccomend ?
Springs/ shocks mounted to rear of axel housing .

Thanks guys .

I reread your first post real quickly looking for your current coil over spring rating, if it is a 200 lb. rate I would try either a 130, 140 or maybe a 150 lb. spring
Did your shocks come with instructions to shoot for 2/3 compress height for the ride height ready to race? If so I have heard those same instructions from 4 different coil over companies It works well
The first coil over ladder bar drag race car I worked on and raced had 3.0 inch travel AVO on the rear, it would top them out against the foot brake staging
The first street and strip car I built with ladder bars and coil overs got a set of single adjustable Strange coil overs with 7.0 inches of travel, 15.0 inches fully extended with either 200 or 170 Lb. springs CRS
I switch the rear springs to a set of 150 Lb. springs later on and changed the shocks to a set of Strange double adjustable and that help a lot on the 60 ft. times, especially on bad tracks

Don't forget, the rear scaled weight includes unsprung weight. This must be removed from the equation. My car has never hooked as good it has this year. Just went from 130lb to 125lb. It weighs 3340 ready to race, 1830F/1510R.
Doug

Can’t get a consistent answer from places I call- screen readers, not racers/ engineers, frustrating doesn’t even begin to cover it.
No consensus- this should be math , geometry etc.

I never saw how much shock/spring travel you have. More travel should lend to a lower rate spring. For my $.01 (can't afford $.02), here's my calculations.

LR- 737
RR- 845

Total rear weight is 1582 pounds. As stated above, deduct the unsprung weight of the rear axle, wheels and tires, etc. I subtracted 250 pounds here and ended up with 1332 pounds rear sprung weight. Divide that by two (two tires) and I get 666 pounds to be supported per side.

If you have seven inches of total travel, maybe you would want to compress the spring four inches per Cab's 2/3 rule-of-thumb. 666 pounds/4 inches = 166.5 pounds/inch spring rate.

If you have ten inches of total travel, maybe you would want to compress the spring six inches. 666 pounds/6 inches = 111 pounds/inch spring rate.

Q.E.D.

That's my theory anyway. Check some of the chassis books and see what they say. You may have to test a few spring rates and shock settings to find a good setup? Hopefully this can get you in the ballpark.

It's going to have a 150 or 170 spring on it, depending on how much energy you want to store in the springs. 150s will take a good shock to control the housing on the hit.

Need to know shock manufacturer and part number, or extended, compressed and installed lengths.

Does it have an adjustable shock mount so that ride height can be adjusted independent of shock installed length?

Why are the ladder bars wonky one side from the other? Is it sitting that crooked or not put together right? I see you said it was level. Was that eyeballed or measured?

Once it's back together, you'll have to neutral everything and start over with the corner weights.

Weight distribution has less to do with hooking (or not) and more to do with leaving and driving straight.

thanks Floyd,I appreciate it.

Strange S5206 SINGLE ADJUSTABLE ( He thinks thats the shock, i have measurements coming)

Stroke 5.52″ / Extended 17.15″ / Compressed 11.64″

With .563″ Bump Rubber Installed
Stroke 4.957″ / Compressed 12.203″


Recommended Ride Height

13.875″ – 14.50″

Accepts 12″ x 2.5″ ID spring

Strange S5206 SINGLE ADJUSTABLE ( He thinks thats the shock, i have measurements coming)

Stroke 5.52″ / Extended 17.15″ / Compressed 11.64″

With .563″ Bump Rubber Installed
Stroke 4.957″ / Compressed 12.203″


Recommended Ride Height

13.875″ – 14.50″

Accepts 12″ x 2.5″ ID spring

Corner weigh details

LF-973 RF-809

LR-737 RR-845

LEFT- 50.7 %----1710

REAR- 47.0%----1582

CROSS- 45.9%---1546

TOTAL--3363 With driver and all fluids in car.

Front ladder bar points are in neutral position relative to front holes.
2.5 degrees down on front - drivers side.
O on passenger side.

Thanks Cm.

I'd probably start with a 150, and run the shock at about 13.750 C-C at ride height. That shock should work if it's not worn out, but you'll have to crank it up some. I'd like to see a DA on it though.

Beyond that, I'd want to know what's going on with the bars. Way heavy on the RR if the driver's in the car.

Quote"I'd like to see a DA on it though. " end quote.
Please forgive me- my mind isn't responding to "da" nomenclature today- probably just too dang tired.

I too am concerned as to why right to left weights are so far off.
weighed a 63 sport fury as well last night, 3700 lbs and weights all looked good - as expected.

There is nothing on the 65 mechanically or installed that explains to me why weights are so skewed unless ladder bars are really tweaked hard.

I looked at all adjustment points and same thread counts everywhere or, within one thread.

I guessing we need to loosen everything up , put in a 150 spring and re-weigh a nd see what shows up then???

please advise.

thanks so much.

Bars varying 2 degrees from side to side is substantial. Something is bent, way out of adjustment or installed wrong. Thread count being close on all the adjustments kind of rules out the thing being adjusted that far out of whack. Is there an adjustment link provided in the bars?

DA = double adjustable shock.

Is the rear end back braced.. if not I would
look there first to see if its twisted.. the
2.5 degrees is a fair amount and I'd look at
the axle housing

What are the front ladder bar bolt heights from the ground with driver in the car? By the weights shown it has a ton of preload on the RR, +100lbs. That could account for some or all of the ladder bar angle difference. I'm assuming the angle was measured with the driver. No way you need 150lb springs in my opinion. This video is almost your weight with 122lb springs/6 cylinder bars.
No problem with weight transfer.
Doug
https://www.facebook.com/debby.kersantywright/videos/10211668943904056/?t=7

That car leaves hard .
This car isn’t pulling a tire off at all at 675 hp, 5400 stall and built/ rollerized 727, 4:30 gears on a 29 x12.5 x15 tire.
Engine was stout on both chassis and engine dyno, really nice tq/ hp curve.

He was told tonight to just leave the coil overs “ loose “ ( not snug to coil pockets) to help get the spring/ shock compression needed.

Rear is braced .
He was pulling 1.48 60 foots, leaving wheels up but bent housing pretty bad.
Built a new housing with bracing and ladder bars , best was 1.46.
End of season ( he came in 3rd on points in spite of all the problems last year) and we put car in chassis dyno .
Then pulled engine and went to engine dyno ( engine builder unit for fast cars, extreamly conservative , heartbreaking to many) and pulled 675 hp .
This showed about 24 percent chassis loss.
We found frame bent on driver front and had put on chassis table to confirm and have fixed- confirmed and fixed.
Then added braces , new converter that better matched his dyno numbers ( old one was an old J converter that had been repaired/ reflashed many times and was flashing 4800)
Found driveshaft front yoke wasn’t long enough- only engaging trans output shaft 1 1/4 inches- new shaft.

First time out - car just won’t hook, finally gets another 1.46 60 ft.
Loses In semi finals running his same old dail in .

We take it to do some chassis tuning- I shoot video.
No separation - zero .
Spits the shaft - bad u joint clamps, they just broke.

We have studied the video intently , over and over - rear of car just isn’t budging at all- like it’s sitting in bars instead of coil overs.

At 12 lbs of air cold ( before burn out ) car isn’t hitting tire hard at all.
He was told this evening to leave a 1/4 slack on the springs when rear of car is hanging ( springs not snugged to cups)
None of the nuts were locked on ladder bar adjusters OR the alignment bar.

Was told the weights were so far off because tensions not exactly the same on the torsion bars.

I agree torsion bars need to be right and that setting preload on passenger rear will effect drivers side torsion bar .

But that’s way over a 100 lbs in front and back.

No on easy adjustment - just standard compitition engineering ladder bar kit.
We didn’t install it - just trying to help sort it out.

My guess is we need to take everything to slack , make sure torsion bars are correct with new springs and car at ride height and start from there.
I can confirm it’s a 12 inch spring at 200 per inch rate.
Shocks are 17.5 long extended and by leaving the springs loose1/4 to 1/2 ( not snug in the cup ) , putting the car back on the ground gives 14.5 length eyelet to eyelet .
So that’s 3 inch’s compression if starting with a loose spring on a shock with 5.45 stroke.
Strange single adjustable shocks- everything is new ( well, about 8 passes)
Slicks only have one season on them and they don’t race a dense schedule at all here in his class.

Car should be really close to 6.41 but runs 6.60 and has to dial in 6.73 ( 1/8 )

Has a points race next weekend so- hoping to get this sorted quickly.

I have never hear of people running 200# springs
on a car in that weight range.. with the 1/4"
of space your just trying to make the spring
lighter in weight(cant happen)in my car(lighter)
I use 90# springs.. you just want them to hold
up the body.. the stiffer they are the harder
to get transfer(no movement in the rear)

Hey Guys: wanted to update folks and say proper a proper “ Thank you” as best I can from here.

The update : We put the 150lbs coils in the rear, 4 cornered the car and ended up with 23 lbs heavy on passenger rear and drivers weight distributed pretty evenly over car/ drivers side .

Car went lazer straight , best 60 ft ( 1.46 ) and ran it all night.
Ran best time - 6.58 ( 1/8) and ran it consistently .

Still not where it should be, what’s desired realistically but, man, what a beautiful change in the car.

Thank you to everyone here- literally , just a huge thanks !!
Best community I have ever had the pleasure of associating with- just top drawer!

Still little movement/ weight transfer.
Bump stops were too tight so we opened that up to get some movement there.
I still think rear springs are a little to heavy , i’m Thinking the car will like 130lbs.
Ladder bars are nuetral - parallel with ground / middle Hole, May need to drop them down one but would like to see video of the hit and 60 ft first .
He should be able to get my video this weekend .
Car ended up at 3340 lbs with driver/ helmet / jacket in car, fuel cell full.

Most of the “ imbalance on the 4 corner weights was in the torsion bars - they were fighting each other.
Main thing right now- car leaves/ runs straight thus safer for everyone , it’s quicker as well and it’s not beating the car up .

Thank you all very, very much.
Any new advice is welcome of course!!

Blessings of Grace and Peace
Rusty

Congrats on your improvements. Race ready mine is 3340lbs also. It uses 125lb springs. We've run it as heavy as 3420 to make index. The last 3 passes in 4200-4500 D/A; 1.308, 1.308, 1.303 60ft. Lighten up those springs. That'll help it pitch rotate.
Doug

Thanks dvw.
What length shock are you using if you don’t mind me asking?

He had already bought the 150lbs springs by the last time we posted DVW, I think the jump from 200 to 125 was a little worrisome.
I rode in the car yesterday and, it pulls hard, its just a transfer
rotation issue imho.
Car IS very stiff.
put a floor jack under lower control arm near ball joint- whole front end come up- both sides.
Grab frame connector at rear, whole side comes up etc

So, chassis is pretty stiff and well balanced now, car finally going straight, true for him.

First run on new set up- things happened fast enough he hit the rev limiter at 6800 before completing shift.

If you dont mind me asking- you know about what hp your running- would like to know where cars are comparable to help in estimating changes.
He is at 675 at the moment, likely make a little more with a new carb, some tuning etc.

Thanks so much.

correction- 3345lbs

LF- 920 RF-832

LR- 787 RR- 806

LEFT 51.0% 1707

REAR 47.5% 1593

CROSS 48.4% 1619

TOTAL 3345

He has seen a 1.46 60 before, but never consistently, it was dead nut 1.46 last time out, really bad air down here right now in 95 degree temps.

Yesterday we went from 88 degrees and 84 % humidity to 97 degrees with 37% humidity , then down to 82 degrees with 48 % humidity- just gotta love it- grin.

We are just starting ( beginning ) to get our heads wrapped around weather/altitude density etc.
I read a couple fairly short engineering papers on timing and air/water density last night- we have so much more access to data today than 40 years ago - its amazing.

A Big thank you to Dom as well for help in tuning and trying to understand carbs and weather.
Thanks Dom.

Shocks are 17"/11" travel. Never dynoed. My bet is 900+. Trust me we've chased traction as we run 10.5's. It is now VERY good. Learn from my mistakes.
Doug

"a correction CM: He does have lighter spring tension torsion bars , RUNS TRAVEL LIMITERS."

I see a problem there, friend had a 427 Vega, very hard to hook the tires, no rotation. He sold the car and the first thing new owner did was remove cable limiters off the front a-arms. First time out with no other changes carried the front wheel 1-2 ft and would hook on snott and picked up 2 tenths.
Original friend wanted the "pro stock look", didn't like the tires hanging down on launch.

Agreed Cudaman- We took those off yesterday, front-end had close to zero travel, at most 1.5 inches.
Car now has stock bump stops and thats it- start from there.
I think the rear springs are still tight .
Car doesn't have same power DVW has but i think I can coax 690 out of it.
its an 11.5 tire, 29 inch.
I think 1.38 to 1.42 60ft is possible but, thats just my math and could easily be wrong.
He foot brakes and leaves at 1800 if memory serves.
Hopefully i will get video sent to me of tire hit, car attitude this evening.

btw- front shocks are 90/10 and set at that- i don't think there is enough transfer yet for porpoising to show up but, we shall see.
I put wire ties on rear shock stems to see what movement we are getting there- at least in one direction.

Springs are kinda stiff but I don't see that being that big a problem. Most ladder cars separate when launched so I thinking the instant center could be off (too low), bind in the bars (take one bolt out at the rear, adjust heims till it just slides back in, this is at rest on level surface), make sure pinion is straight or slightly down aiming at the trans.
Might add, make sure driver is in the seat when adjusting that bolt. After all is bolted up adjusting springs or rate separately doesn't work, they work as one on a ladder bar setup, even the front tb work as one so adjust ALL before that bolt goes back in.

Fooling around with a calculator and dream wheel. Looks like about 52% on the nose. That's OK.

Dream wheel and calculators say 675 HP @ 3350 is 9.80 potential in the 1/4 or 6.20 in the 1/8. It's mostly all in the 60'. Car should be mid to high 1.30s at that power to weight. Is it a 3 speed? Good converter with the right stall?

Freeing up the front end was a good move. If it wants to rotate and can't, it will be a turd. The amount of lift can be controlled with an adjustable limiter and/or a good shock. 130 springs is borderline but might be OK at that rear axle weight but you'll have to control the hit with the shock once the car leaves like it should. Pay attention to the separation and that it's not crushing the tire at the hit.

thanks Cm:
He has strange single adjustable back there right now- brand new.
So your math says we are close with 150 lbs springs?

converter is new FTI 5100 stall, we could move it to 5500- we have one free re-stall.

4.30 gear, rollerized 727- all good parts.
air isnt good here.

My dumb ass is better at helping than actually racing that's for sure........it will come around and that twin blades pretty bad azz as well..........

A 150 will hold the car up at ride height and should be compressed some. So will a 130, but I expect that would really need to be wound up. The difference is the lighter spring will be compressed more. That will store more energy to make the suspension more "lively", easier to separate and apply the tire. This can be useful on a mild combination that needs help. More power, more gear - it doesn't need the help. It can get to be too much and beat up the tire.

We have 170s on a car real close to your deal weight wise, but it's violent combo with quite a bit more power and we're also using a real good shock to control it. It doesn't need any extra help from a lighter spring.


I think the 150 is the right choice. But, you can put a 130 on it and see how it works. Not like it can't be taken back off. Lord knows I've tried enough stuff that didn't work...but knowing what doesn't work is as valuable as knowing what does.

What is the compressed length of your 150 spring at ride height?

cant measure as car is in the road .

Haven’t read the whole novel yet, but our ladder bar Duster has 12” 120’s on it.

Do you recall how far the nut was wound up the shock?

My 125# put the shock very near the center of the travel at loaded ride height with almost exactly the same weight on the rear.
Doug

2+ INCHES CM
Car moved my wire ties up 1 1/4 inch
12inch spring
I can get you the data when track opens.
rough night last night, really bad Oklahoma air/ thunderstorms were rolling in and hit 15 min after last run, video showed car porpoising on launch, couldn't see tire well in video but, best i could see, it looks like 12 lbs isn't flattening the tire out.
Honestly don't think there is enough transfer and holding it to squash tire.

Im trying to figure out jetting now, car lost over a tenth, 60ft went up badly.
AFR went from high 12, low 13 to 11's.
sheesh.

Rusty what are the rear shocks set at?
You could very well improve how the car works with a DOUBLE adjustable rear shock. Would not be a bad idea to put them on the front also!!


Mike

2 inches is a fair amount of compression. 130s would have to be compressed another 1 1/2" to hold the car up. Don't think you want to go there.

I assume the shock is about 13.75 or so installed at ride height?

It's porpoising because it's trying to pick the nose up and can't. It's like your rear end when you're trying to pick up something up from the floor that's too heavy. The car is rotating around the front spindle. I'm assuming the travel limiters were taken off already?

If this thing has that much power, something is off somewhere. Unless it's completely blowing the tires, this thing should be way quicker, even if some of the adjustments are not quite right. What's it MPH?

Cm: Im guessing as to spring compression right now- race got cancelled due to weather and he just wanted to load up and come home.

Im certain of the 1 1/4 shock compresion.

Yes, that power is real, dyno we use is from a known engine builder- very conservative, heartbreaker for newbies type deal.
Its primary purpose is engine builders test bed for engines he is contracted for- Fast cars.
Chassis dyno confirms engine dyno and vis-versa.
In this case, how we confirmed we had to much chassis loss/ converter issues etc.

Yes, car isn't right yet.
Not blowing the tires off though, may be crushing drivers side, couldnt get a picture.
The way the porpoising looks, part of it may be drivers tire may be getting crused, going round, getting crushed and then standing back up and out, part of it looks to be shock too loose, not controlling extension/separation- need to turn them up, slow extension down.

Other than that, I'm kinda stuck unless ladder bars are in wrong hole - they are parallel to the ground, middle hole of range.

Front end- light torsion bars, 90/10 adjustable shock on 90/10 setting.
No limiters other than the bump stops are 3/8 extended ( I think that needs to come out, not sure they don't need to be shorter even.

Guy has a big points race next weekend , lot of cars will be there etc.
Im going to go unless something crazy happens that way i can get video the way i want it and get data live and after the runs during test and tune.

We did put the HHR fan on it and that helped a lot with temps.
Car was way down on power, running really rich in that air.
Air density was 4000+ ft .
89- 95 degrees temps and humidity from 55 to 80 percent because weather moved in we didnt expect- wasn't in forecast until they were close to event.
Air actually got worse as temps cooled because water stayed at 119.8.
At least, according to what i have learned so far- thats why carb went so rich.
Two carbs were tried- both went hard rich.

70: Rear shocks are strange single adjustable- brand new.
Thats what was spec'd out when he had the ladder bars put in .
Guy has spent a goodly sum of money in last 18 months:
New rear-end housing, back brace, three driveshafts, tail housing/sprag/trans rebuild twice, moved from 4.10 gear to 4.30.
Ladder bars, springs, new shocks from and rear, new converter, fan etc, etc.

Not much faster yet, but straight, consistent, safer - yes.
Its there, we just have to figure out how to find it.

Air is hard on us down here- its 101 degrees with 50% humidity outside my shop, 29.75 at 544 ft above sea level.

Wallace calculator says:

Your 1/8th Mile ET is 6.62
Your 1/8th Mile MPH is 110.57
Your HP Correction Factor is 1.11
Your DA (Density Altitude) is 3,244.10 feet
Your DA (Density Altitude) is 988.65 meters
Your Air Density Index is 87.8 percent
Your Grains of water is 153.13

Cm- Mph has been averaging 104-105 1/8 mile
146 60ft
6.56 et

ez 440-1 cnc max wedge
12.5 comp
indy single 4 max wedge
holley 950 hp , rebuilt by Pro systems
673 hp @6300- nice long curve ( 599 @ 5200 and still pulling 624@6600 , tq is 662 @ 4600.

I just got an LM2 as well as an AEM fail safe - have it in his car to log runs, we will tune with the LM2.

Get AFR straight this week will help a lot and if we can get chassis to work-nice hotrod!

Thanks

Your P/W is very similar to my old race car. Best ever 10.13@131. I've learned a little about stuff since then. My take is there is not a ton left in your set-up ET wise. Consistency, yes. What I've learned; converters can be looser than what you think. Shocks can be tighter than what you think. Rear gear has little effect if it's close. Air pressure can be higher than you think. Tubes are worth a lot. Lightest springs/torsion bars that will hold the car up. You may not need Santuffs, But the better the shock the more consistent the car. Video from the side is invaluable. Do I know it all? Far from it. But the car was good enough that it went 35/36 rds, 8 races/7 wins before going red last Saturday.
Doug

and there ya go DVW.

I think there is a little power left to be found, definitely chassis tuning to be done- no doubt on that and then she is what she is- just win rounds being consistent.

Car did well this weekend in Denton.
Really bad air but, with Dom’s help, we were able to get within a 10th of cars best.
Everyone else in this class was over a 10th off, we were under- thank you Don!

Springs- man, we are getting close guys.
Took another 3/8 inch of front end limiting out which put it at stock or really close.
Car is leaving wheels up, but even tightening up the extension, it’s dropping back down to fast, unloading the rear .

Anyone know where I can get 140 and 130 lbs springs?
I had hoped Strange and/ or Hyperco had them so I would be working with apples to apples.
We are still only compressing the shock 1.250 , I think 140 lbs springs or, 130 might get us to correct in shock travel and thus shock control.
I like to make small changes, one at a time and record them.
All the spring catalogues I have or see online jump from 150 to 125 and I fear that might be too much and even if not, will wonder if that “ just right” spot was missed.

We did hit the tire harder, enough so that we had to add air and didn’t have more spinning, tire stayed a bit more round and 60 ft picked up slightly .
My “ gut instinct “ is: If I can get a bit more chassis rotation and hit on tire/ control of the release of that hit, we could raise both tire pressure and rpm at launch a bit.
Leaving now at 1800 rpm.
I think 22-2500 is possible with good paddles/ no crush and solid hook.
Rpm graph from runs indicates ( to me anyway) we might need a tad more tire slippage to help driveshaft speed.
I shot video of each launch for tire and car attitude.
Good front end movement now, still not much on the rear , jerking tire up, dropping down pretty fast, loaded and unloaded tire on drivers side and car “ try’s “ to pull tire off ground again when tire reloads .
Right now car looks more like a lever action than a chassis rotation- if that makes sense.
It’s my belief if I can get rotation and control extension , we can carry the tire, plan driveshaft speed and drop 60 ft times a good bit .

Thanks again for all the help and any more ideas you might have.

Rusty

I went through some chassis tuning on my old pump gas Duster to get the best results.
I would lower the ladder bar to the lowest hole on the chassis and then next raise the launch RPM if the ladder bar adjustment helps
I did end up with Koni SPA front shocks and Strange double adjustable shocks on the rear, I think it would run low 1.40 to maybe high 1.30 60 ft. times on 315x60x15 M/T ET Street radials launching at or above 3300 RPM
It was 49.5% on the rear weight distribution with me in the car weighing 3450 Lbs. full of fuel. It ran a best of 9.993 at 134.7 MPH in the late summer at Woodburn corked up on Oregon 91 octane non ethanol pump swill
It ran 10.69 at 124.+ MPH the first time out at Woodburn in the fall of 2005, .7 ET and 10 MPH gain with a lot of work and better parts
Test, test and test some more
Ain't learning how to go faster fun

indeed Cab!
I was honestly pretty pleased we gdations on total weight of car ot the car within a tenth of best in really nasty air and, was able to keep it there and that with a brand new carb.
I wore poor Dom out but, God bless him, he helped tech carb/afr remotely both Friday and Saturday- thanks again Dom!

Car is getting there, just not enough chassis rotation yet to properly use the shock.
I found hyperco does make a special spring at 130lb for Strange and think we are going to give that a shot.

These companies base their recommendations on total weight of car instead of unsprung weight, which i think CM tried to clue me in on and im just now getting my head around.
I think 130lbs may be just about right.

Yep, have fun, the problem solving is a blast.

I have a pair of 125# Hyper coils used for test fit. Pay the shipping and I'll let you try them out. If you like em $70 for the pr. If not send them back.
Doug

might take you up on that .
Get back to you later in the week.