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