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Disappointing first time out

Posted By: 68LAR

Disappointing first time out - 06/20/11 07:47 PM

We had just finished installing a 440 in my friends' '65 Coronet. We pulled his 383 that ran a best of 12.5 something. Using the same cam, heads, carb, headers and drivetrain, we were looking for at least a .5 decrease in ET. The car ran the same as with the 383. We picked up .3 only when we dropped the exhaust at the collectors. It has a 3500 stall converter, 4.30 gears and 28" tall slick. The car launches a lot better, but seems to slow down from around half track on. I'm thinking this thing should be 60'ing in the low 1.6 range instead of 1.7-1.8 and running at least low 12's to high 11's. Any suggestions?
Posted By: maxi426

Re: Disappointing first time out - 06/20/11 08:00 PM

Check fuel pressure? Motor might be making a little steam, and now has a fuel supply issue?
Posted By: RemCharger

Re: Disappointing first time out - 06/20/11 08:12 PM

440s have a lot extra weight flapping around in there. Not really surprised they run the same.



j/k

I would look at compression differences and maybe cam timing?
Posted By: MR_P_BODY

Re: Disappointing first time out - 06/20/11 08:15 PM

Quote:

Check fuel pressure? Motor might be making a little steam, and now has a fuel supply issue?



I would look at the fuel supply
Posted By: dennismopar73

Re: Disappointing first time out - 06/20/11 08:23 PM

not a big enough change 383-440 ,
12.50 and you only did the swap to the 440,
12.teens 12.20s good air 12.0s
you could actualy have a fuel issue, which could have held the 383 back??
Posted By: 383man

Re: Disappointing first time out - 06/20/11 08:30 PM

How the trap RPM ? I use 4.30's with a 30" tire on my old 440 and would shift at 6200 and trap higher then that. The short stroke 383 liked the gears but with 28" tires and 4.30's it may like 4.10's or a taller tire better depending on the cam and heads. Ron
Posted By: Cab_Burge

Re: Disappointing first time out - 06/20/11 08:58 PM

Quote:

We had just finished installing a 440 in my friends' '65 Coronet. We pulled his 383 that ran a best of 12.5 something. Using the same cam, heads, carb, headers and drivetrain, we were looking for at least a .5 decrease in ET. The car ran the same as with the 383. We picked up .3 only when we dropped the exhaust at the collectors. It has a 3500 stall converter, 4.30 gears and 28" tall slick. The car launches a lot better, but seems to slow down from around half track on. I'm thinking this thing should be 60'ing in the low 1.6 range instead of 1.7-1.8 and running at least low 12's to high 11's. Any suggestions?

Several thnings, on the cam did you install it at the same lobe centers on the 440 Or did you advance, retard or just stick it in on the dots If you guys just stuck it in you need to degree it or at least check and set the intake lobe centers Second thing ,what do the spark plugs look like now from the 440, if you put new ones in Lots of ways to slow cars down, even when your not trying to do that Let us know what you find and do to correct it
Posted By: 68LAR

Re: Disappointing first time out - 06/20/11 10:20 PM

Cam was degreed to a 105* on a 106* recommended. My first thought was fuel pressure, but he doesn't have a guage visable from the cab, so it could be monitored. He runs a blue pump with 3/8"
line. If it would go low 12's we both would be happy. This is, as I stated, where we were hoping to be on the first outting. Trap RPM is 6000, but it takes a seemingly long time to gain rpm between shifts. Plugs looked good, no fouling or over rich indications.
Posted By: tboomer

Re: Disappointing first time out - 06/20/11 10:33 PM

How are the valve springs?
Posted By: Sport440

Re: Disappointing first time out - 06/20/11 11:23 PM

Did you ever run the 383 with the exhaust removed? How bigs the carb and cam?

Even though you ran the same heads the pistons depths difference between the two motors could change the compression abit or a bunch.

Also like stated with the volume of air and fuel being pulled through with the extra cubes you could be running out of fuel.

Witch intakes are on each motor. A good tell tale sign of the second half loss of ET would be the MPH difference between the 1/8th and the 1/4. At the 12.5 zone it should be about 24 to 25 mph.

As simple as the change seems , theres still lots to consider.
Posted By: go green

Re: Disappointing first time out - 06/20/11 11:36 PM

Quote:

The car launches a lot better, but seems to slow down from around half track on.



Your heads will only support so much power , by raising your cubic inches you are making it sign off earlier.
Posted By: Bigcube

Re: Disappointing first time out - 06/20/11 11:43 PM

Quote:

Quote:

The car launches a lot better, but seems to slow down from around half track on.



Your heads will only support so much power , by raising your cubic inches you are making it sign off earlier.


x2, and the converter probably flashes higher due to new found torque making it launch better. But you could find more ET in it if you start optimizing the rest of the combo.
Posted By: 68LAR

Re: Disappointing first time out - 06/21/11 12:22 AM

Never ran with the exhaust uncorked with the 383 as far as I know. We wanted to keep everything the same just change engines. Of course the intake had to be changed. The 383 had an M1. The 440 has a Torker II. Carb is a Demon 850. Valve springs are Comp 928. 150 closed 371 open. Cam is also a Comp. Solid flat tappet, 252* @.050 with .540I lift. The 383 had dome pistons at 11.2:1 compression. The 440 is .030" over and has flat tops at 10.5:1 compression. Quench is .054". Pistons are .015 in the hole and .039" gasket. I think he should go a little bigger with the cam, maybe to a 259* or 260* and more closer to .600 lift. He does run race gas.
Posted By: Sport440

Re: Disappointing first time out - 06/21/11 04:06 AM

You left out the head info

And the MPH change between the 1/8 and 1/4.
Posted By: Thumperdart

Re: Disappointing first time out - 06/21/11 04:13 AM

Quote:

Cam was degreed to a 105* on a 106* recommended. My first thought was fuel pressure, but he doesn't have a guage visable from the cab, so it could be monitored. He runs a blue pump with 3/8"
line. If it would go low 12's we both would be happy. This is, as I stated, where we were hoping to be on the first outting. Trap RPM is 6000, but it takes a seemingly long time to gain rpm between shifts. Plugs looked good, no fouling or over rich indications.

I would NEVER drive or race a car w/out a fuel pressure gauge visible. If I didn`t have my gauge in view, my car would be jacked staying in it at ZERO pressure. I`d mount in in view and go from there.
Posted By: 1967dartgt

Re: Disappointing first time out - 06/21/11 04:21 AM

Did you change the carb at all when switching from one motor to the next?
Posted By: dennismopar73

Re: Disappointing first time out - 06/21/11 06:17 AM

Quote:

Never ran with the exhaust uncorked with the 383 as far as I know. We wanted to keep everything the same just change engines. Of course the intake had to be changed. The 383 had an M1. The 440 has a Torker II. Carb is a Demon 850. Valve springs are Comp 928. 150 closed 371 open. Cam is also a Comp. Solid flat tappet, 252* @.050 with .540I lift. The 383 had dome pistons at 11.2:1 compression. The 440 is .030" over and has flat tops at 10.5:1 compression. Quench is .054". Pistons are .015 in the hole and .039" gasket. I think he should go a little bigger with the cam, maybe to a 259* or 260* and more closer to .600 lift. He does run race gas.



jmo bet the 440 has 9.1 comp add the weight of the 440 over the 383,
point comp , yep ran the same or close , the 383 should been quicker
see previous post
Posted By: 68LAR

Re: Disappointing first time out - 06/21/11 01:00 PM

Quote:

You left out the head info

And the MPH change between the 1/8 and 1/4.


Sorry 'bout that. Heads are 906's with home port and big valves. 2.14/1.81. Only slightly shaved to get them level. MPH at 1/8 was around 88. 1/4 MPH was 110-111.
Like I said, everything was the same as with the 383,except for the intake. We wanted a true comparison. When it ran the same, this is what was dissappointing. Ya' the 440 is slightly heavier, but it also gives 53 more cubes and a bunch more torque.
Posted By: dennismopar73

Re: Disappointing first time out - 06/21/11 01:37 PM

75-?100 lbs down on comp, the 50 plus cubes off set the weight & compression diff
something tells me the 383 wasnt running correct either,
something was amissed there? may be the same reason the 440 doesnt run alittle better, timming /shift point fuel delievery,convert/ trans issue?
the 440 does have a little more torq # yes,
if everything the same, the 440 would run slightly better,
not no half sec, jmo
hard to say what yo have going on over a keyboard , could be several issues??
Posted By: DodgeCharger

Re: Disappointing first time out - 06/21/11 04:04 PM

Was the mph the same as the 383 also?
Posted By: RemCharger

Re: Disappointing first time out - 06/21/11 04:18 PM

Domes in the 383??
Thats a tough little motor to beat. After 60 feet, the 440 better have a little something extra at the bottom of its knapsack, or its gonna fall behind.
The b motor should have been timed at 41~42*, and the 440 needs good degrees too.

What was the deck height on the 440?
Posted By: 68LAR

Re: Disappointing first time out - 06/21/11 05:29 PM

The 440 picked up 1.5 MPH over the 383 at the big end. Timing on the 383 was at 40*. The 440 is at 38*. For what the 383 had in and on it, I think it ran pretty darn good. This whole combo, old and new, puts a new meaning to the term budget build.
Posted By: Cab_Burge

Re: Disappointing first time out - 06/21/11 05:58 PM

I did a manifold dyno test several years back on a stroker 440 motor(484 C.I.) with a set of worn out stageIV heads stock 440 port size) we tried a Torker 11, Eddy Performer RPM, and a Mopar M1 single plane, same motor same day twenty minutes or so apart to make the changes. The Torker 11 was the worst, the RPM was better down low, below 5000 RPM and the average(3500 RPM to 6500 RPM at 100 RPM intervals)) HP and torque was real close to the same between the M1 and RPM. the single palne was better above 4500 RPM but that was a meduim weight(3500 LBS minus driver)street car so we left the RPM manifold on the motor Do you have access to another intake to try
Posted By: gregsdart

Re: Disappointing first time out - 06/21/11 06:24 PM

Very little left to say after the above posts. Compression cost a little, shift points may need to be lower, manifold cost you some, and then the motor is corked up by the same flow as the 383 used. That in itself might be part of the issue. Did you try collecter extensions? Jet changes? I would jerk the heads and go with a steel .022 shim head gasket to get compression and quench back up there. At about .050, the help of quench starts to go away.
with a looser converter ,a better intake and a cam as big as the mopar .590, this deal should go mid elevens, even asd heavy as it is. Check cranking compression, try running the plug gaps tighter, pick away at every thing you can think of. The performance will come.
Posted By: JohnRR

Re: Disappointing first time out - 06/21/11 06:32 PM

What tube size on the headers ? Also should have used the .021 steel shim instead of the .039 headgasket .
Posted By: Beatnik

Re: Disappointing first time out - 06/21/11 06:38 PM

I'm guessing what has been mentioned...more cubes, means more fuel demand! I had a Holley blue pump that barely kept up with my 360 Magnum! Centrifugal force + add'l volume may be starving it by 1/2 track I'd bet...upgrade to a better pump and even 1/2" line maybe. Just my two cents....no change.
Posted By: dennismopar73

Re: Disappointing first time out - 06/21/11 06:45 PM

the 383 sounds like pretty swell piece?
timming at 40-41, ???!!!! wow if i did that push my valley tray plum out around the intake,
never over 36 run 32-34 shift point ?? 6200-6500 tops
440 shift 5800-6200
JMO ?
Posted By: DodgeCharger

Re: Disappointing first time out - 06/21/11 08:21 PM

I use to run 12.00 along time ago in a 440 cuda.
If I remember correctly the car ran 113 to 114 mph. With your 111 mph you should be able to run at least 12.20's.
I ran the holley pump with the regulator I don't remember if it was blue or red but it was the bigger of the two. The 440 should be a 1/2 second faster but I think you should have put in a bigger cam. If you have the same intake,heads and carb I would think you would need to have a bigger cam to get the same cylinder fill or efficiency per cubic inch as the 383.
Have you tried different shift rpms? With the same small cam as the 383 the 440 hp would peak at a lower rpm then the 383.
Posted By: 68LAR

Re: Disappointing first time out - 06/21/11 11:06 PM

As stated, this was the FIRST time out with the new engine. What we did try at the track was:
Swaped carbs with my tried and tested 930 Proform."I ran 11.8 with this carb".He gained about .040 and about 1/2 MPH. So we put his Demon back on. We changed plugs to a hotter plug. Picked up a little, but nothing to write home about. Increased timing from 33 to 38*. Picked up .050 to the 12.48 where we are at now with closed exhaust.
Headers are 1 7/8".
Uncorked the headers just for sh---'s and giggles.
Car ran a 12.28. So we know that the exhaust is restrictive and are going to work on that.
Posted By: DodgeCharger

Re: Disappointing first time out - 06/21/11 11:35 PM

Did he ever run the 383 with open exhaust? Most likely the 383 would not pick up as much. Some of these guys that think a 383 is a better motor than a 440 are off base. Your buddy made the right move. Dollar for dollar the 440 will out run the 383.
The exhaust is what is restricting your 440. The 440 is exhaling more than the 383.
I have full 3 " exhaust on my 850 horse Cuda and uncapped I only pick up less than a tenth.
If he wants to run through the exhaust he should start by upgrading the exhaust.
By the way I am running Magnaflow mufflers. They are straight through.
Posted By: moparmanjames

Re: Disappointing first time out - 06/22/11 01:03 AM

My Roadrunner had a similar combo at one time.

800 DP
Team G intake
Home Ported 516's with 2.14I 1.81E valves
509 Hydraulic cam staight up, 10.2:1cr
Timing was at 36
3500 Stall converter
1 7/8 headers and flowmasters
4.30 gear and 12.5 x 28.5 MT sportsmans
3700 pounds with me in it.
12.1 at 110 mph in the Las Vegas heat, around 4100ft density altitude.

Your friends car should be in the very low 12's to high 11's like you estimated.
Posted By: dennismopar73

Re: Disappointing first time out - 06/22/11 01:32 AM

Quote:

Did he ever run the 383 with open exhaust? Most likely the 383 would not pick up as much. Some of these guys that think a 383 is a better motor than a 440 are off base. Your buddy made the right move. Dollar for dollar the 440 will out run the 383.
The exhaust is what is restricting your 440. The 440 is exhaling more than the 383.
I have full 3 " exhaust on my 850 horse Cuda and uncapped I only pick up less than a tenth.
If he wants to run through the exhaust he should start by upgrading the exhaust.
By the way I am running Magnaflow mufflers. They are straight through.



really hard to say why either motor dont/didnt run,
for the straight across trade he did no he would run really close,
the 383 had compression, yes lighter , ,wether it 5# or 500 #
the addiadge was you could take 20 # battery out of the front of the car, take it put it in the back and thus lose 100# out of the car,
(rumor)
he used the same came heads carb, i have done this with not much pickup for the work involved.
now he can work on the combo he has , yes to me that combo should be mid 11 car, , that being said,, the 383 should be real close as well
i have done this deed, several times only to be disapointed at the end result,
did the exact thing when i ran small blocks , took out 360 270 h comp cam 8.5 ccp , put in realy swell 340, 10.1 nice pistons , warmed up heads solid cam ld 340 intake race gas the whole deal,
didnt pick up squate, ran it tune it, sold it , put 360 back in changed intake from the 340, ran faster , everyone said the 340 would flat out run that stock 360 didnt wouldnt , couldnt ,
why idono,
as for this poster , wish you the best, hope you do see that 12.0 11.90 ticket, or faster
good luck, dennis
Posted By: Sport440

Re: Disappointing first time out - 06/22/11 02:42 AM

If everything was exact engine wise between the 383 and the 440, I would expect about a .5 better ET too.

But the 383 has .7 more comp then the 440, Theres 2 tenths IMO from that .5

The Torker II intake is a dog below 4500, some will say 6000 rpm. theres another 1.5 tenth with that 3500 vert your buds using.

Also, as you already found out, the exhaust is not guite up to the task with the extra cubes.

IMO, the above added into the combo, plus the Extra weight of the 440 kept the ETs around the same between the 383 vs 440.

The fix, Swap out that Torker II for a RPM.
Throw on a steel shim to gain some comp. back.
Upgrade the current exhaust as you have planned.

Then you will have your .5 gain or better IMO,

The 111 MPH of the new combo suggests sub 12,s as is with just a Vert swap alone. Id do that later after fine tuning what you have now.
Posted By: viperblue72

Re: Disappointing first time out *DELETED* - 06/22/11 02:50 AM

Post deleted by viperblue72
Posted By: viperblue72

Re: Disappointing first time out - 06/22/11 02:56 AM

Do the math. Hes nowhere near 10.5 to 1. Lucky if its 9.5 to 1.
Probably 2 points down from the 383.
Posted By: Sport440

Re: Disappointing first time out - 06/22/11 03:48 AM

Quote:

Do the math. Hes nowhere near 10.5 to 1. Lucky if its 9.5 to 1.
Probably 2 points down from the 383.







I did the math as you suggested.

With slightly shaved 906,s you can expect 88 cc chamber volume or higher.

using.

87cc chamber
4.36 bore
4.50 gasket bore
4cc valve reliefs
.015 in the hole
.039 gasket ========= 9.75 comp.

With only a slight shave on the 906,s the Comp,s probably even less then that. More like 9.5


There are no measurements to estimate the 383,s true comp. I based my opinion on the stated 11.2 and 10.5 comp difference.

The 906,s chamber would need to be around 79cc or less to hit the 10.5 comp mark.
Posted By: 68LAR

Re: Disappointing first time out - 06/22/11 12:35 PM

Ya, you guys are right on the compression ratio. I was using 84 cc to get 10:1. Don't know why I was getting 10.5:1 ????????????. Not knowing exactly what the cc's of the head are, I have to go with the owners memory on how much, if any was shaved off. I'm going to recommend pulling the heads and going with the steel shim gaskets. He's stuck with the Torker II for now. Personally, I didn't think that was a bad choice for an intake. Thanks for the info and recommendations.
Posted By: dennismopar73

Re: Disappointing first time out - 06/22/11 03:56 PM

i have run that intake , then a team g, and a m1,
the dif is 10th between all three on my combo,
is it something yeah but money and time vs pickup , its a tune thing for me not the holdback!

not to brag , but i did say the reasons behind my thought why it didnt run faster,
have to ask why the change??
the 383 aint no slouch, it will run
was it tired? hurt?
the steel shim might get you close to the 10,0 comp
still think there was something behind that 383 causing same issue,
convert timming shift fuel ??,
this is a street car mostlsly?
im in race car mode,
Posted By: JCCuda

Re: Disappointing first time out - 06/29/11 04:49 PM

Have the valve springs been checked? Just because the spec says 150 lbs. on the seat doesn't mean that that's what they are. You should have at least 140 lbs. on the seat. If the pressure is just low enough it won't sufficiently control the valve. I saw it on a friends 440 that out of no where slowed from 11.20's to 11.60's and the mph was down also. He checked the springs on the car they were all around 120-125 on the seat (very similar cam specs.). Installed new spring's @ 140 on the seat et and mph came right back. I also think pulling the heads to change to a steel shim gasket is a good idea but while the heads are off why not have the heads cut to bring the cc's closer to 78-80 cc and the springs can be checked at the same time.
According to the Kieth Black compression ratio calculator;
80cc chamber
4cc for valve relief's
.021 gasket
4.5 gasket bore
4.35 bore
.015 deck
3.75 stroke
= 10.81 compression
If you cut the heads and or change the gaskets don't forget to check piston to valve clearence.

Attached picture 6705403-A10-21-200809;05;25AM.jpg
Posted By: Dodgem

Re: Disappointing first time out - 06/29/11 05:36 PM

The heads will only support 500 to 550 hp and both motors probably max the heads out.
So they will make the same HP but the 440 will peak at 15% lower rpms.
RPM performer intake will help.

I would try shifting about 5800 will want way lower shift point than the 383

I would degree the cam in at 102 should pick up some!

That 440 should run fine on straight 93 octane! more octane will likely slow it some!

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