Not happy with my Atco outing,Pulled the engine out

Went to Atco a few weeks ago and not impressed with my performance.
Saturday I made 2 passes on pump gas to burn up what was left from street driving.1st pass just the way I was street driving with 4 lbs of boost it went 10.16,,UNcapped no jet change it went 10.05 on the lean side. Last pass I upped 2 jets and 2 lbs of boost and it went 9.9.
Sunday 1st pass was 9.72 @ 140.11 with 6 lbs. Next pass Took 2* of timing out and it went 9.89 @ 139.0,,,,went to 10 lbs and it went to 9.76 @ 140.68.
Just seemed no matter what I did it wouldn't go over 140 mph.Best pass to date is a 9.3 @ 137 with 6lbs through the exhaust.
Did a compression test & leak down cold.20 lbs spread on compression and 19% on the leakdown,and yes I should have performed it hot but I had the covers off already so checked the lash cold and that was all over the place as well.
So my OCD pulls the engine out for an inspection and found NO problem other than a few exhaust leaks.Tomorrow or saturday We will take the springs off and check them.I hope to find a few soft ones.
That leads me to the 1st question to you all,,,,,if a spring or springs go into float,how would that effect the Race pak recording?? Would it show in the AFR or the RPM? Could the 2200 DA with 85* heat and high humidity kill off 8 to 10 MPH??

https://www.youtube.com/watch?v=sR_u5pkB6is

So where did you hear the 19% leaking from?

Pistons are out,rings look great,bearings look fantastic.No cylinder is more than 1 thou out of round.

Part of doing a leakdown is listening to see where the air is leaking out. exhaust valve, intake valves, rings. I use a short section of hose held to my ear. Its impossible to look at rings to see if that's the issue. It could be the ring gaps or even the hone job.

Was wondering if you checked your fuel flow. I was having similar problem a few weeks ago with not wanting to mph. I usually take the li ne off after the regulator and see how long it takes to fill a 1 gallon jug. My issue ended up being the rotor in the fuel pump being stripped and not catching all the time.

Al what did your data logs look like? Were you just looking at MPH? What did the incrementals look like on the time slips?

Wasn't this 'new combo' supposed to be able to handle more than 6psi of boost?

Have a Magnaflow 500 with the filter.Rebuilt a year ago,but will have a look at the filter.

Data was good,,,afr 13 @ WOT,but the plugs showed fatter,,,,,,,,,,will be testing the bosch sensor in a friends car for verification.

Me thimks the driver is getting old and needs a real cruiser !

I’ve got that Demon you ordered .... and I also have a new home for Yurr 63 ... I’ll put that hemiroid in my Bay Boat !

THE DRIVER needs to do a self LEAK DOWN !

Add fuel to that thing.. it wants it

If only there were a way to test the motor...... with the different levels of boost..... to figure out how much difference there actually was...... and then figure where the jetting/timing needed to be for best power at each step....... and then maybe know how quick/fast the car should go based on the power it makes.

I know...... crazy idea.

Great idea but the weather throws a huge monkey wrench into the equation
If I only had an extra $5k for EFI I could keep the rest of my hair.

I will be testing my 0/2 sensors in a friend car this weekend to verify my readings,it might read 13 when the plug and combustion chamber says it's it's in the 11 range.When I test in the street I can only click high gear and get out of it due to stupid speed!

Let’s try this again......



Probably easier to keep hauling the car all the way to the track, hope you get a couple of good passes in...... look at the time slips and data logs......... and wonder why it’s not doing what you think it should.

Instead of a day on the dyno ...........where you could make 15-20 pulls and have a bunch of data to look at ..........that isn’t compromised by track conditions.

Any more fuel and I will be trailing black smoke going down the track!!

Then your O2 is way out of wack.. a little testing will help.. like you plan on
good luck

Two step process.
Step 1) dyno, figure out under controlled conditions what fuel trim is needed for each pulley.
Step 2) track, on bad air day with middle pulley see what works best. What % different from dyno. Move the range of trim down that %
or put hemi bumper sticker on, worth 3-5 mph.

or stop eating!:)

I plan on some chassis dyno time,but after a few pulls the blower case gets heat soaked and would need some time to cool. At the track with no hood it does not get as hot. The dyno I have access to does not have fresh air intake but plenty of fans to help circulate.So when I get on the dyno it will be more for finding the timing sweet spot. When I get the O/2 sensor issue figured out I can get very close with street testing.
Will you miss the steaks????

Screen shot over the stripe.

I think the O/2 sensor is in a good spot. Right in the elbow,flow should hit it well.

Opinions??????

I am with John, I'd wonder where the leak was coming from and would be chasing it.

I am probably mistaken as usual but it seems a noted professional may be offering his services, buried somewhere in this thread?
At least, I imagined that I was reading something like that. Must be a Fig Newton of my imagination

I would look at increasing the jetting at the track in the 1/4 mile until the MPH slows down, if you can't jet it rich enough to do that you don't have enough fuel delivery, volume
Test, test and test some more until your happy

Thanks Cab,my O/2 recordings are making me crazy!! The plugs tell me I'm good or even a little phat.....

Blower motors are so much fun, huh
On your deal I would work hard on getting the primary side of the carb to be great at light part throttle driving with low boost and use the secondary tuning for high boost with better fuel and reduced timing for all out WOT driving with more boost
Do you have a boost timing retard feature on your ignition? If not why not

Yes Cab,I do but don't use it yet. I have an MSD programmable so my timing curve I set manually,,,,,for now.When I get on a chassis dyno where I can see it at work then I will mix it in.Still trying to keep it simple 'till a get a good grip!

2 questions;
1 where is the burn on the ground strap, I can't see it in the picture
2 if it is really reading 11.7 on A/F, that's way rich

Can I see inside the plug on the porcelain towards the bottom with a flashlight?

[quote=camastomcat]2 questions;
1 where is the burn on the ground strap, I can't see it in the picture
2 if it is really reading 11.7 on A/F, that's way rich

Can I see inside the plug on the porcelain towards the bottom with a flashlight? [/quote
The above screenshot is going over the stripe.I am still experimenting with the 2nd gear RPM as it comes so fast I have been over 7500 I need to verify my O/2 is reading properly.Over the weekend We will check it in another car with a Big Stuff 3 to see if the calibration is off.I'm buying 2 new ones anyway but want to know where I am!
This vid shows plugs from several passes.

https://www.youtube.com/watch?v=NwN1Ra8fb3c

That plug looks good to me. I like to see a very light tan color on the bottom of the porcelain and the burn on the ground strap at the bend. I'm not an expert at reading plugs by any stretch reading spark plugs. I just know what I like naturally for my NA motors. If the car is repeating, that's the important thing. When my racepak O-2's read 13-1-13.4, my engines are the happiest. I know they do vary though. I almost wonder if you're driving through the converter or something like that as the RPM seems high but can't see it at the top of the run. BTW where are you taking the O2 reading? It should be taken at the finish line at maximum RPM. As far as leak down numbers, it does seem a bit excessive. On the video, it looks like the plug is oil soaked? Is that just the light or? Is there a reason you are not using E85 or Methanol instead of gas? Just curious. There are more experienced people on this board than me especially on blown motors.

camastomcat,This car is mostly street driven with 4 lbs of boost burning pump gas.E85 is great but not available everywhere so besides needing a 20 or 25 gallon cell I would need to carry a few 5 gal gas cans.E85 also has it's limits of octane requirement.
I a believing more and more it was just poor weather and the tune was off.It came off the hit pretty good,,,,jsta didn't have the top end charge I'm used to.

Itis, Honestly, from my recollection of that day, at the hit, your car seemed a little stressed out as far as RPM's. You just might be going through the converter as mentioned above. The car almost sounded Funny car-ish as far as RPM's.
Also, remember the weather was a bit sticky and no oxygen even though it wasn't too HOT,HOT as far as temps. I don't know what the Barometer readings were.

Still pretty stout for a HEAVY street driven car.

Not the right way to go about track tuning but you can probably go back and find the conditions online. Lots of apps for that now. I personally write conditions on every time slip I get.

Good idea. That weather info is more important then the best results.

I agree with camastomcat. The only thing I'm not sure about is heat range. If that's an NGK plug, in that picture it's a bit hot...maybe 1 range. If it's a champion it's 2 ranges too hot. With blower stuff I don't like blowing the cement off the shell all the way around. 3/4 around is better. But you are on E85 so it may like a bit more heat.

Any changes to the combo since then?

Better track?

Better air?

1st trip to a track with cut outs open, timing is 30* to 2800 rpm and ramps down to 26* by 3200. I put 2 clicks into compression after spinning on the 1st 2 passes. FMJ,could you hear or see the whole pass?? How did it sound?? That photographer should cut a hellova light! That pass was a 1.41 60

That was me that shot the flick using Ralph's camera. I gather he sent you the photos since I was snapping him and the rest of the Supercar guys. The car sounded loud to the point of almost erratic in the first 300-400 feet and the it cleared up in the Amen corner, but then again it's a Hemi.

Copy that,it was the first time UNcapped. Carbs felt very crispy!!

If the valves were to float,would anything show in the recording data like in the AFR or RPM????

Dumb question... but why is the driveshaft speed so much lower then the engine RPM at the stripe?

I assume it's a setting in the race pack, but might want to correct that so you can see if its driving through the converter.,

QUOTE - it was the first time UNcapped

Could be an interesting little nugget of info?

There's no driveshaft or wheel speed sensors hooked up so the data is off. Last time Al posted a pic of that screen I got fooled by the same thing.

Al, maybe its time to hook more sensors up so you can actually take advantage of what the the Race Pak has to offer instead of just using it as an A/F gauge. It's certainly capable of providing a lot more than what it's currently showing. Stuff like EGTs, manifold pressure, driveshaft speed etc. More info = less guessing!

The only thing I might add would be an EGT sensor on each side left in the leanest cylinder.
Now I have RPM,driveshaft RPM,water temp,Fuel & oil pressure,voltage,AFR right and left, intake air temp and boost.

That engine/ds ratio is not accurate and it could be important in trying to figure out why it won't get over that MPH hump.

An engine rpm/ds rpm ratio of 1:1 = zero slip. If your ratio was truly 1:1, the engine rpm and ds rpm would be the same. I agree with Dizuster's suggestion that some parameter in that channel needs to be changed. Only other reason the ds rpm could look like that is that the sensor is not reading correctly which is not out of the realm of possibilities.

In the first screen shot you posted, it shows engine rpm at 6,494 and DS rpm is 3085 which calculates to about 2.1 though the field says 1.0. In the above pic, the ratio calculates to about 5.0:1 (7,514/1,486) which can't be right on any planet, even Planet Itis!
.
A ratio of 2.1 actually seems closer to reality and good or bad, would calculate to around 20% slippage. Is this the same unit you had before you changed stuff? Maybe post what the engine rpm and ds rpm are at the shift points to compare. My guess is that if it's more efficient off the line than at the stripe it's too loose?

Racepak engine/ds ratio

The second screenshot shows the whole screen and you can see the data is for the point where the white vertical line is........ which on that particular shot is the top of first gear....... so there is naturally going to be a big spread between the crank and driveshaft rpm.

Looks like it’s working okay to me.

So I come out of this with some 20/50 on my face.There were no issues with the engine after teardown.I will replace the Bosch o/2 sensor and read the plugs at the next 1/4 event.I plan on going to http://southmountainraceway.com/ on Friday,kick off on thursday and the fairgrounds on Saturday.

Al, i’m driving to Carlisle thurs. if i dare to race Fri and break somthin, could you flatbed me home, and i driive your blown hemi home for you? Ok -i didn’t think so.

Have fun, call me about the wing flaps on aeroplanes

Good news for you KID,I can tow BOTH cars and you can hang out in the A/C with me and pay TOLLS!! There have been many a time where I come with one and leave with TWO!

hay iTiS ....did you dIsCoNnEcT the driveshaft on that CornyNet ?

[quote=Cab_Burge]Blower motors are so much fun, huh
Oh!! I'm having so much fun in the sun...........................NOT!

That’s great!! I was just kiddin with ya, but thats great to know.