im puting a jegs 3500-3800 stall in tomorrow. how low do u think i can get my 60 ft with my set up? my lca and penhard are boxed in to

 

1.70ish or better.

 

and mid 12's too.

 

i got it in.what a big help. whats the best way to take off with it?

 

From an idle, or as close to an idle as yu can and still get clean throttle response. (some single plane manifolds)

 

do i need a trans cooler and i dont drive it much

 

I've pulled 1.8 60's with stock suspension (except for Eibach Sportlines which probably don't help much and a panhard rod). My shocks are the original 100k mile junkers. I feel I should be able to possibly pull a 1.7 next year with more practice launching.

 

whats ur stall and 1/4 time

 

on regular tires? or stickies? if you're on sticky tires 1.80's should be effortless, even 1.70's would be easy. I have 27x10.5 Hoosier QTP's and completely factory suspension minus the sway bars. On a decently prepped track I could do 1.56-1.58 60ft's all night. No effort whatsoever... just a light burnout, footbrake the car to like 1800RPM and take off with the nitrous on a WOT switch.

 

I have a T5 with 3.23s in the rear. I'm using drag radials. I've ran a 12.8 so far; and I'm pretty sure I'll go faster on the motor. No nitrous yet. I'll replace the rearend/transmission before nitrous.

 

key there is t5 and 3.23. the 3.23 are not helping ur 60ft

 

Not to steal your thread, but yeah. I was wondering about going with a lower gear like a 4.11 or something. But I've noticed that right now, I cross the finish line pretty much at red line in 4th gear (5500). If I put in 4.11 or even 3.73's won't I be in 5th gear then?

And I'd never give up my T5. Well I'd give it up for a T56 or Tremec TKO

 

I'd say yes if you're going to do any street driving. Even after a single pass in my car the temp goes up to around 160 ish if I remember right. That's with a 4,000 stall and cooler. On the street it only warms up a little bit.

 

codename id say 3.73. with 4.10 and 26 in tires in the 1/4 im 5700rpm i think and trap 105

 

That depends on your engine's peak output, you may want to be pulling beyond 5500rpm. What's your heads/cam combo? What is the car's trapspeed like now?

 

I've run 12.8 at 108. I feel the motor has much more if I can get my 60' down. Here's the motor. It's a build out of Chevy High Performance. Run on 91 octane.

406ci with dished pistons
Vortec heads
1.5 roller rockers
air gap intake
Lunati 00010 cam (230/230 .480"/.480")
Holley 750 cfm DP

I have a 412ci no roller rockers and a 700 cfm Holley DP. I run open headers at the track (Hooker 2460 shorties). I'm running a 16 inch iroc rim with a nitto drag radial. I just shift at 5500 every time. That's what I should do right?

Their Dyno numbers.
RPM Torque HP
2,500 477 227
2,600 483 239
2,700 488 251
2,800 489 260
2,900 490 271
3,000 493 282
3,100 503 297
3,200 511 311
3,300 516 324
3,400 521 337
3,500 525 350
3,600 525 360
3,700 524 369
3,800 522 378
3,900 519 385
4,000 515 392
4,100 512 400
4,200 508 407
4,300 504 413
4,400 500 419
4,500 491 420
4,600 480 421
4,700 471 422
4,800 464 424
4,900 457 427
5,000 449 428
5,100 440 427
5,200 431 426
5,300 420 424
5,400 411 422
5,500 406 421

 

SO how you like the new converter?

It should have really woke the car up. I run a external cooler as well as the factory radiator cooler. Thats the best way I have found.

Are you going to get some track time? Let us know what it runs.

 

That motor would probably tolerate more carb, a 750 or 800, you've feeding a pretty good sized motor with quite a bit of duration on the cam (that was 230* @ .050 right?) I would be interested to have seen what a dyno pull to 6000rpm would have looked like. Maybe 5500rpm is about right. Experiement some at the track, make a few passes shifting at 6000rpm and see if the ET drops or climbs. Shifting at 5500rpm on a carbed/cammed 350 seems low, but I'm not sure about a 400. One thing I'd bet is that your carb is holding you back.

 

I was told by a lot of guys at the track to go no larger than a 750. They said this 700 would work well. Duration and lift are @ .050.

 

Hmmm... I would think with those cubes, and that much duration on the cam, that you'd pull a fair amount of air. Most mild 350's run well with a 750 carb, I can't see a 400 with decent cam demanding less...

Then again Engine size (cid) x max. rpm/3456 =cfm

400ci x 6000rpm / 3456 = 694cfm

And thats at 100% VE, take that to 85% and the cfm is 589.9

Gotta take it with a grain of salt though, we all know 600cfm on a cammed 400 is undercarbed, signifigantly.

 

i love it.i just put a cooler on 2 hrs ago.im going to the track tonight to see what car does. if it dont rain. and what psi should i run in my mickey thompsom et street radials? as a start point? it 25 psi now

 

start at 20psi. that's what i run and it works really well in most cases. i'm running a 275/60/15 on a 15x8 wheel. go down 1psi per run till you hook.

 

Looking forward to it! We have EXTREMELY similar combos and my 3500 stalled th350 will be in and driving by noon tomorrow and at the track on sunday.

 

not to happy with the runs tonight. my best time of the night was 12.992
@ 103.9 mph on a 1.837 60ft. i got it to hook 3 times out of 8 the rest was 2.2xx 60fts time. i have seem to lose some power up top to. why? last week 105.xx mph this week 103.xx mph

 

How was you leaving the line? What RPM? Were you letting it flash, or holding the brake are a certain RPM?

What kind of air pressure were you using? Did you check the front tires. You would be suprised how much you can pick up with 40psi in the front tires. Better roll out.

 

Also are you running LCA relocation brackets? They made a big difference on my car. I am also running the Hoosier QTP's. I dont know how they compare to your M/t ET Street Radials, but I love my Hoosiers.

 

How was you leaving the line? What RPM? Were you letting it flash, or holding the brake are a certain RPM?holding breake to 1500 rpm and flashing

What kind of air pressure were you using?20psi Did you check the front tires. no
----------
no

 

I'll tell everybody again, throw all your math, throw all your hot rods and super chevies in the garbage when you start talking carb sizing...or go fast combos in general...throw out the engine and chasis dyno results too...the only way to know exactly how your stuff will respond is to change stuff on the track.

Our 383 in the s10 was at 105%VE on engine dyno, only pulled 697cfm so dyno dude said the 750hp we did pull with was perfect. i had'em throw a 950hp on and numerically we lost hp and it threw our tq curve for loop, on the track with the 750 it ran good, we finally put my 950 on it...and it ran great- .15 increase on a fat tune from my car...and the 750hp was tuned perfectly.

I've never really seen a car overcarbed out there...i was running this 950hp on my old 9.3:1 355 and it went faster in the 60', 18/mi, 1/4mi, and mph than the 600VS, 650DP, 750VS, 700DP, 750HP, 830DP....at this point after all i've seen, i have zeero faith in any formula, seen them busted tooo many times to have any faith at all in them...you will too if you hang around the track enough..same with magazine articles...they make good toilet reading/entertainment...and tha'ts about it...i look at those magazines like WWE wrestling, and believe them about as much too

 

Exactly. Just try some different things. You said the car felt weak at the end of the track, that continues to make me think you're under-carbed. Like I said, a 750cfm carb will usually run pretty good on a mild 350, and your air demands are higher than that, so I would think 750cfm would be a starting point.

 

i found my vavle lash was off alot (1/4 turn) on a few vavles never have rechecked it till yesterday. i knew going down the road car sounded rough. now it dont sound rough any more and really pulls hard in third gear now. and friday night it was poping at the end of the 1/4. so could that of been why it wasnt pulling hard up top? on the carb can i change the jets to give it more up top? i have 72/77 jets in it now

 

To find out where you need to be jet wise, forget looking at plugs, esspecially if you have a good ignition system, you'll increase jet until you might as well just pull the carb and put a gas can upside down in the intake...watch your mph, go up 2 sizes front/rear after 2 baseline passes and see what happens, if your mph increases, upjet again 2 sizes...if it falls a bit, drop back one and see what happens, if it's still slower then go back to best mph pass jetting. You cant compensate for undercarbing by increasing jets...you'll kill the performance earlier in the run. And you'll find too the bigger the carb the bigger the jet you'll run...more air needs more fuel.

Do yourself a favor before you start messing with anything and chasing your tail...borrow some real slicks so you DEAD HOOK everytime, otherwise if you cannot duplicate a time slip within .005 each run (not factoring in major weather changes) all your doing is wasting your time and energy since numbers will be tainted...so either try the relocation brackets and hope that makes those radial things stick each pass, borrow a set of real DOT bias ply slicks/full slick...either way, you need to have every increment on the track identical each run...if your spinnning, you are'nt going to get any relavant info to base changes on....I know a few guy on here are having luck with the radial things, but life is soo much easier by just installing the hoosier QT pro's...they'll hook on a poorly set up car on a poorly prepped track every pass...not to mention they last longer, 60' faster, and ET quicker than M/T et streets...that's been proven here too we turned all the diehard m/t fans against m/t once they finally gave the quick time pro's a shot...and i think you will too if you ever switch.

 

i will get some for next yr. i need some 28 in tires

 

What are your trapping rom wise now? by all accounts 28" tires and 4.10 gears go together like peanut butter and jelly, just curious as to where your taching across the finish line currently?

 

around 6000 for some reason other night it was really high like 6200