Took my car to track first time with new motor

[69bananabeast]

didnt go as well as I thought it would but not too bad still lots of variables to figure out.   

446  Automatic , 10:1 ,  870 street avenger,  dual 2.5 exhuast , mechanical  528  lift , indy heads closed chamber 78cc minor port,  flat top speedpro, M1 single plane , Indy EZ heads , deep pan, Tci  727  ,  2400 stall ,  8 3/4   3.73 sure grip  (supposedly it's suppose to be around 500hp  (gross im sure)

1st  pass    Full Exhaust       didnt know shift points so from first I shifted at  4K rpm

                React : 1.26
                60'     : 2.26
                ET     : 14.83
                MPH   : 96.42

2nd pass   Full Exhaust

              React : .99
                60'     : 2.23
                ET     : 14.27
                MPH   : 96.48

3rd pass   Open headers   Towards the high end i had a blown header gasket , started backfiring at high end from here on after 5300
     
               React : 1.22
                60'     : 2.18
                ET     : 14.3
                MPH   : 87.84

4th pass   Open Headers

              React : 1.20
                60'     : 2.19
                ET     : 14.33
                MPH   : 100.56

5th pass Open Headers

            React      : .750
                60'     : 2.15
                ET     : 14.39
                MPH   : 98.62

6th pass Open Headers

             React : .958
                60'     : 2.33
                ET     : 14.71
                MPH   : 97.57

starting from the 2nd or 3rd pass I started shifting around 5300 RPM

Variable 1) on 3rd pass  blew a header gasket  . Found that when mechanic was putting engine back together they only put one copper header gasket in and the other cork.
Variable 2) Need to do better burnouts
Variable 3) Think timing might have been a little off
Variable 4) Carb might need rebuild
Variable 5) Got bigger tires i need to put on 295/65's (currently 255/60's)
Variable 6) put my hemi scoop on my hood so i can get better airflow and an air filter

Any advice ?

[Duey]

Not that I'm an expert or anything, but the 2400 rpm stall seems way too low and may be why your 60 time is pretty high (reaction times aside)...with that build, you should be high 12's....although not only your ET but your trap speed indicates RWHP around the 290-300hp mark.  Incidentally, were you on a .400 or .500 tree?

Cheers,
Duey

[69bananabeast]

im really not sure which tree

actually i believe its a .500

[Duey]

.400 sec is a pro-tree...you stage, then all three yellows flash on together, then the green .400 seconds later.  On a Sportsman's tree, the yellows light sequentially, .500 secs after each other.  Thus, a pro-tree starts (green) .400 secs after the last racer stages while a sportsman's tree will start 2 secs after the last racer stages (.500 sec for each of three yellows and the green).  Not that it really matters though, I was just wondering how your track was set up...a lot of guys find a pro-tree (or a 400 tree) harder to start from...

Cheers,
Duey

[dodge freak]

It should not break up at 5300, maybe start to lose power but not break up. You need to find out why-could be lack of fuel or weak spark but thats slowing you down too. Might even start sooner and you don't feel or hear it.  Does it have a hard time hooking up? With all that power maybe he can't floor it till 15-20 mph, that was a problem with those old cars, they had so much power it was hard to take off very fast.

[Duey]

It should not break up at 5300, maybe start to lose power but not break up. You need to find out why-could be lack of fuel or weak spark but thats slowing you down too. Might even start sooner and you don't feel or hear it.  Does it have a hard time hooking up? With all that power maybe he can't floor it till 15-20 mph, that was a problem with those old cars, they had so much power it was hard to take off very fast.

DOH, missed that...that combo should still be strong at 5500 and make 6000.  Jetting on the secondaries wrong/lean?

[69bananabeast]

might be lean , throttle  cables been screwy ,  you can half a$$ tune it for a lil while and it'll run pretty good otherwise at idle it'll be around 1K RPM and then get stuck at 1900rpm . Lately idling at a light it fluctuates from 500-300 rpm .   Need to do a better job warming  up the tires as well.  I've rarely ever done burn outs so I think it would help to fine tune that

It would be a .500 tree then

[firefighter3931]

The mph is low so the engine is down on power. If it was making a true 500hp then it should be pulling around 115mph in the 1/4 regardless of the ET. 

The stallspeed is too low, inmo. That car would do much better with a 10in turbo action converter with 3500 stall. 

Your 60ft times are killing you. It should be in the 1.60 range. This is a combination of suspension tuning and lack of traction. Work on getting it to hook and the ET will drop.

The carb sounds suspect ; make sure the throttle is opening completely when the pedal is all the way down to the mat. Check the float levels to make sure they're adjusted properly and you're not running out of fuel at wot.

The ignition curve might also need some work....more initial timing and less mechanical. You need to map it out to see what you've got and tune from there.

You've got lots of good parts in that engine....just needs a few tweaks here and there, inmo.


Ron

[69bananabeast]

So what should I do about the suspension?  only thing i've done is re-sprung the leaves, but if I ever run an event at the track (Domestic shootout/ Weekend Warrior) I have to have stock sspension though im not sure how far that goes.

[firefighter3931]

So what should I do about the suspension?  only thing i've done is re-sprung the leaves, but if I ever run an event at the track (Domestic shootout/ Weekend Warrior) I have to have stock sspension though im not sure how far that goes.

Couple of things will help ;

(1) pinion snubber adjusted so it's touching the floorpan at launch. You'll need an adjustable unit.
(2) drag shocks front and back
(3) disconnect front swaybar at the track
(4) slicks or a good drag radial tire
(5) clamping front segments of the leafsprings...if you're experiencing wheel hop at launch. If not, don't bother.


It's all about weight transfer and keeping the suspension from unloading the tires.


Ron