jas142

How difficult would it be to get a 1991 or 1992 Z28 Automatic into the mid 14s? What mods would be needed?

Thanks.

Black6SpdTA

14's? ah shouldnt be too difficult. get full exhaust (headers, catback maybe high flow cat) gears (if you have 2.73 def get some 3.73), a cam, high flow runners (w/ plenum ported to match) SFC's, LCA's, sticky tires theres a whole lot you could do.

Ray86IROC

Well IF the 91-92 305 TPIs all had the hotter factory cam as several people contend on thirdgen.org, then it shouldn't take much at all to hit 14s. Full exhaust and some decent gears, along with some free mods (port the plenum, shim the FPR, rig up a cold air setup, etc) and I wouldn't be surprised if you nailed your goal. Assuming you launch decently and run at a decent track... To err on the side of caution I'd also think a set of aftermarket runners and some 1.6 rockers would almost insure you certainly get you there IMO. (porting the base would be a great idea too).

Rage

Uh....that all depends. 350 or 305 TPI or TBI. With my car, I took it out to the track the weekend after I bought it and I ran a 15.3X and then a 15.0X. And with the help of Nitto's a 14.9X. I have a 305, and I have SEVERAL things wrong with my car. I have a few burnt valves, my transmission does'nt shift right. It's not as hard as people make it seem. But then again, it all depends on where you live too.

amc91z

I went a 12.41 with a 100 shot and the mods below...went 13.7 on motor in Amarillo, TX...
Adam

TwinTurboROC

my car (89 350 tpi auto 2.77 iroc) originaly went 14.8 @ 93 stock w a **** load of problems....

bald tires
one wheel peel
golf ball sized hole in my maf... 2 of the elements were missing on the heated strand....

and like i said stock... these cars have ALOT of potential... you just got to add the right hardwar to make em alot faster... everyone plays em down that they are slow and bla bla bla... especialy lt1-ls1 guys (dont mean to knock on you guys... but its true) but then you look at the differecnes in teh motors 3rd gens didn come out w alum head outa the factory.... we didnt have 6 speeds... but its **** we gotta deal with... the best way we can... with a sledge hammer

like i said b4 u should be able to get a stock 350 in the high 14 easily... a 305 will be low 15 and w a good driver high 14... outa the factory stock... but it also depends on the condition of the motor high mileage vs' low mileage

edit:
i also forgot a major factor... speed density vs mass air flow mass air flow cars are 85-89 and sd is 90-92...

now in ideal conditioons the sd car will be quicker... but the maf system is alot more forgiving w bad weather.... maf can tune on the fly.... sd is based off of manifold pressure and is a set amount of values... so a sd car will be a dog in realy warm weather where as a maf car will be slightly less of a dog

Rage

Twin TurboIROC is right too. My car did have low miles, I forgot to mention that, it had 85k at the time, which is low for the year, but like I said my car had ALOT of problems. AND..It'd been setting up for almost a year and hadnt been driven or even started that whole time. So, it isnt as hard as people make it seem to get these cars movin. Learn to drive, dont rev it too high when waiting to pop off the line, these cars dont like that, I did 2200 RPM's and that seems to work good, but on Nitto's or some sticky tires more is safe.

IrocManiac

5 Speed 305 or a 350 stock in good tune will do it all day long. I've seen cars in perfect tune go mid/low 14's stock. Saw a 350 Iroc turn a 14.28 at 98mph it was stock (k&n) filters is all.

DarthIROC

Stock they turn decent 1/4 times compared to other cars of the era, but they turn in REALLY impressive 1/8th mile times. The TPI is a low end torque monster. But most on this board can attest that they dont perform nearly as well over 4800 or so RPM. Spend a little cash on a Stealth Ram and I think they help upper RPMs alot.

irocz8957

is it a 305 or a 350?

ThirdGenZ28 92

If its a 350 from 90-92 you should be able to nail mid 14s stock. For me I had a crank pulley, Flowmaster, K&N, airfoil and cheap stuff like that and my very 1st time down the track was a 14.1 and I backed it up with 2 more 14.1x runs and a 15.5 but shush on that one Time in my sig is with a 2k stall, some DRs and a few suspension pieces added and instead of mid 14s Ive clipped off mid 13s, its all in the 60ft.

efizjb

You can belive this or not, because I didn't when it went these times either. I had an 89, original factory 350TPI, crap 9 bolt with 2.77 gears, airfoil, KN filters, dynomax catback, and hypertech chip, low temp thermostat, and bald grand spirit radials, it went 13.83 with a 60 ft of 1.83, don't ask me how it did with those gears and tires, but you can ask many a Mustang guys I hang out with, and it did. It never went that ET again or 60 ft, but typically ran 14.1 with 1.9ish 60 fts. High 13's should not be a problem with a tight 350.