Well, Right now i have an all stock 1988 iroc with a zz4 crate motor, t-5, and 245/50/16 tires. What would it run in this form? I Plan to put on 255/50/16 m/t drag radials, line lock, edelbrock adj. torque arm, LCA's, panhard rod, 3.73 ring and pinion, and a rev limiter. What will it run with these mods. Not looking for anything specific. Is there any chance i can go 12's like this? Thanks. Joe.

 

probably not you may run 13.2-13.5's

 

Engine has the power, problem is these things are PIGS!!! Find some weight to remove and I think 12.8's are possible.

FWIW...do a search on the Edelbrock TA........there are better way to go for a TA.

 

Joe,

Like I recomended before ditch the lowering springs they are going to kill your 60' time even with the lower control arm relocation brackets (run the stock rear springs). Buy your self some 15x8" rear rims with 4.5" of back spacing and put 275/50/15 mickeys. Adjust your torque arm to -3/-4 degrees, throw some lakewood 70/30 front struts on to keep the car streetable, and remove the front sway bar when you are going to the track. you should hit 12s!

If you want to take it a little further relocate the battery to the trunk and put adjustable rear shocks so you can firm up the compression of the passenger as needed.

 

Is it TPI or carb? A couple of people I know have run 12.90's with a ZZ4 crate engine. One was in an 83' Z28, shorties, CB, 4.10's, suspension, 2800 stall, 275/60-15 DR's, skinnies, 750 DP. The car had a lot of launch, I never remember it trapping more than 104-105 MPH. The other was in a 70' Nova SS, heavy all steel car. 3.55 posi, 750 DP, LT's, 3" duals w/ flowmasters, 3000 stall, 26X10 ET drags.

If the car is TPI, I'd expect it to run around 13.4 - 13.6, and have trouble trapping more than 100 MPH. A stock TPI unit will choke that engine.

 

I think you have the power to go 12s but can you get there with drag radials and a 5 speed? You'll probably blow the tires off it. Are you running the factory 7-1/2" rear? If not, ask a friend if you can borrow a pair of slicks - the taller the better. I think with a pair of slicks your car could easily go 1.6x short times and you would be in the twelves no problem. BTW, are you running the HOT cam?

In my opinion you won't need any of these to achieve your goal. I would spend the money elsewhere.

With the drag radials, that may give you a little too much starting line ratio. What gears do you have now?

 

Thanks guys. I can't wait for the racing season but i got my work planned out for this winter. I am on a budget build so for this year I am just going to run it with the 16" wheels and drag radials and the edelbrock torque arm i got on ebay for a pretty much half off price. Oh and yea i am running the hot cam. Thanks again.
two more questions though. What is the best thing to do with tpi my intake? I dont want to spend over $600 and the new BBK intake will be $400 which is perfect. Any chance 1998 v6 rear springs will work in in the iroc? Just put lowering springs in my daily driver so i figured they would be perfect. Joe.
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And i bought a beefed up 10 bolt rear for the car with 3.73.

 

Joe,

The 98 fourth gen springs will fit but used or will require a thicker upper isolator pad to get the same ride height.

Remember do your homework and match everthing from the front to the rear, to reach your goals and get the output you are looking for. I see a lot of guys throw a lot of mony at their cars at the track, put a huge cam and a lot of nice parts in it. But they do not do their homework and as a whole package there car does not perform to its potential, and I line up next to them with my hot cammed LT1 and run a 10sec and run right around them.

I would suggest to purchase desk top dyno, the basic program can be picked up for almost nothing and will give you a rough idea what gains or output to expect with different mods and is a great learning tool.

 

My 92 ran around 8.5’s on the 1/8 back last November with a new zz4 with SLP runners, Edelbrock base ,headers and 24# injectors

 

Well For anyone still interested in this post, I finally got to the track. I ran a 13.665 at 99mph withe a 2.02 60 foot. Any specific suggestions. I came across one problem. I am running the new rear with 3.73's and trapped at 6200+ rpms in 4th(overdrive just bogs out) I am having trouble getting any traction and i am launching at 1800 rpm just to hook so the car has a lot more in it. track conditions werent the best and it was 35 degrees out. If i get more traction, will my rpm/mph go up or down? Thanks. Joe.

 

It's too much gear, if you want to keep the 3.73's - get a taller tire. A 275/60-15 will be 28" tall and drop the revs down some. It will also help out with the launch due to the extra sidewall.

 

well heres my next question. can i get m and h drag radials to fit on my 16" wheel(275/55/16?

 

If you have a 16X8 wheel, I see no reason why it won't work. That's basically equivalent to the 275/60-15's I run, just for a 16" rim. Just realize, your T-5 is on borrowed time. Treat it nice, or it will explode.

 

well the precious owner said its beefed up but will it still be problematic? And everyone tells me "automatic" but i wont do it. I love the stick shift so any suggestions when i blow out the t5

 

depending onyour track conditions and the DA you should be able to run low 13s with ease i ran lo13s with the stock 87 cam and 1.6 rr at sea level on comp T/As 245/50/16.....tried hard for 12s but NEVER got it my fastest was 13.004@107
was able to launch at 2500 w/1.73 60' however the T-5 does not really like being launched like this especially with sticky tires!!!

 

you may want to consider moving to a T-56 6spd for better durability.
my bolt on Lt1 car(in avitar)is bolt on only with 4.10s on bald 315/40/17 nitto drag radials runs very low 13s @3000' da i come across the line at roughly 5700 rpm..
i am trying to understand why your rpm is that high in 4th,are you using the stock tach? that may very well be the culprit they are NOT acurate at all above idle...

 

well i plan to get the torqur arm relocation bracket and when the trans does die, get a richmond or tremec unit rated to 500-600hp/tq

 

yea stock tach

 

Tremec TKO 600, damn near a direct drop in and tough as nails. Plus a better 1st gear ratio than a T56. Your RPM's seem high for only 99 MPH in th elights, but anything much over 5K RPM with a TPI is pointless unless you've got a highly modded system like Dyno Don, or Kevin91Z28, etc.

 

put an aftermarket tach in there and i am certain the rpm will not be that high at the end.
it's almost impossible 3.73s,26" tire,4th gear is 1:1
my trap is 105.20mph in 4th with 4:10s at 57-5800

 

it even sounds like its screaming though at the end but i geuss il do that and find out. Whats a good tach with an easy install. Do you think the previous owner changed the gears in the trans?

 

well the only thing he could have done is used a different tranny. the TPI car has different ratios than TBI it sounds as if you have the TBI tranny in there but still not enough to get you that rpm in 4th,LOL my 4.10s make my car sound like it is real hi rpm

 

Look at your 2.02 60' time (no traction), you must have been spinning off the line. This will eat up a lot of you first gear RPM and put at a much higher RPM at the ent of the track.

Are you still running those lowering springs and a front sway bar? 3.73 gears and a 26" tall tire with that tranny will get you down the track like 92optopws6 said. You need to get traction and lower you 60' time.

 

I've heard .1 off your 60' is .2 off the big end. Pulling 1.7/1.8 wouldn't be bad. That would most likely get you into the low 13s.

 

I put an autometer tach in and I am almost 1000 rpm high with the stock tach and 5000 rpm! I never got the car into the powerband for the hot cam.

 

this cam has no problem with 6500 rpm in an Lt1, with that said,a TPI will not like the rpm but can do it shift that sukka at 5800/ 6000
and enjoy the difference....if it does slow down it's the runners fault come down to 55-5800

 

yea i knwo that cam likes the high rpms but will the motor take it? Does anyone know what a zz4 can handle? And yes ill be changing the runners and throttle body after i get DR's.

 

ZZ4 will go the distance for you, the original 474/510 cam i had in my old zz4s were shifted at 6500 OFTEN for a few years. a buddy of mine has one right now with a cc306 which sees 6800 quite a bit and has been in the car for 3 years now..

back in the early 90s i installed just about 24 ZZ4s in F-bodies at my old shop ONLY 1 got hurt and that was on a 200 shot destroyed 4 pistons on the 5th pass used the crank in another build without any machining.....

 

wow i never thought they could take such a beating i was really starting to worry thanks.

 

they are quite dependable, just be certain you have agood chip tuner or you will have issues. synthetic oil etc. helps alot......pull those heads off and have them ported and add 2.00 1.55 valves and see how much she likes it

 

Ran a 13.3(1.81 60 foot) at cecil county dragway on saturday. Shifting at 5000, with bfg drag radials(18psi), edelbrock tq. arm, Tubular LCA's. Still had the lowering springs in and no weight removal. Also have torque arm reloc. bracket from UMI. NO clue where my fuel pressure is. Hoping for twelves after runner, plenum and tb swap.

 

What was the MPH?

 

103mph

 

Good job!
you are on the right track,i still feel you should be ablle to run 12s as she sits, do you have a chip burned?
HSR,58mm,30lb inj.,1.6rr TUNING! lo 12s possibly hi 11s depending on good weather, weight traction, driver skillzzzz......awesome bro!

 

i have 1.6rr, still have to adjust fuel pressure, pinion angle, i have a mail order tune for now, planning on dyno tune after i do the intake. Should i got 58mm or 52mm throttle body? What runners should i get? Do i need bigger injectors?

 

I prefer the 58mm especially with a stick shift car, are you concerned with emissions or is it a major factor? If not i would look into a StealthRam afterall the corvette style EGR can be adapted to this manifold i did mine about 6 years ago but that car is long gone. I do suggest larger injectors 24-30lb...
As far as your tune, i would upgrade your pcm to the Ls1 pcm available from
http://www.eficonnection.com/eficonn..._cylinder.aspx tuning is more convienent due to availability, just something to keep in mind

 

What would i run....??? I have brand new motor 350 bored .30 ported and polished and resurfaced heads new gm lifters and 1.6 roller rockers. new crank comp cam .264 duration with a 460 lift. headers, 3 inch slp exhaust

 

we can help you better if you can answer some specific questions:

what heads & type of work done?
actual cam specs(cam card)?
stall speed if auto?
gear ratio?
TPI mods?
injectors?
chip(tune)?
suspension mods?
radials,drag tire?
altitude you are at?

 

Ok heads are original heads with port and polish and a 2 angle valve job.
cam part # comp cams part#08-501-8
factory torque convertor/is an auto
3.23 gears
no mods to the tpi
24 lbs injectors
no chip i dont have one of those shi**y ebay chips for the thermo. but not on
--on suspension
kumho tires
houston area so i dunno what the alt is.

 

Great HRP thats where i ran my TPI cars 89-95,15' above sea level
stock 90-92 5.7s were running 14.1-14.4s stock avg.
knowing this you should be able to run 13.7 however the stock TPI is holding you back! you need bigger runners and need to modify the plenum for sure cut the airboxes completely out, underdrive pulley kit,2600stall and headers are manditory for performance... at this point you should be running 13.3 with roughly 1.8 60'.......

my best results for my 91 was
stock shortblock
L98 vette heads(comp springs 120 seat press.)
stock 87 cam w/1.6rr
slp runners,worked plenum
hooker shorties
pulleys
perf.resources chip
cut air boxes w/k&n filters
T-5 trans
3.45 rear end
M&H racemasters
these cars love manual trannies!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
(4) destroyed T5sthey were way beyond the 300tq they were rated at!

 

You mean the factory air box?? If so i took it off and put a k&n filter on the mafs

 

No good bro, that air box is your best source of cool air..what year is your car i am confused, your avitar says '91.. maf sensors stopped in '89

 

My bad Tb. but you said cut the box? what box is that

 

He means cut off the bottom of the boxes under the air filters. It's one of the free mods.

 

something sound wrong here my car run 13.8 at 102.44 on a 2.2 60ft with a stock vortec motor. how does vortec 255hp motor put down number with a zz4 motor and hot cam?

 

what vortec motor and what intake set up are you running?

 

just a stock 97 truck motor and summit stage one intake and 650 dp

 

Wow. That's an incredibly quick trap speed for a stock vortec engine....


My cammed, vortec headed 400, has only managed 108 mph, granted it probably has some more in it yet, but still.

 

Jumped in this kinda late, sorry if this has been mentioned.. zz4, at 99 MPH your car is good for around 13.3s given you are effecient. So if you want 12's shoot for around 102/103 with good launch.. Your car is not going through traps at 6200 in 4th gear with 3.73's unless your tires are 21" tall..
Your tach is very off, or you have a serious clutch slipping problem.
At 6200 rpm you would trap 126 with 3.73 and standard 26" tall tire.

2.0 60ft is not terrible with street tires at all, especially with 5speed.
You can do better, but not bad.. Get some good stickies and launch well without bogging, you will see a nice gain.

DR PERFORMANCE, where are you from in Pittsburgh? I frequent PRP alot..
Live near west newton area.


Sorry zz, just noticed you chgd tach and got her running well.. Good job, nice times.
Get an intake and enjoy another 1000 rpm.. Your 103 trap will get you 12's with 60ft..

 

You can spin the whole first 1/8 mile, rpm is still relative to speed!
99 MPH spinning or not does not change your rpm. Spinning can increase trap speed sometimes, however
most effecient cars will lose some MPH spinning ..