So I just bought a 87 Iroc Z28 it has the original 350TPI and the heads were rebuilt last year, it also has the 9 bolt Borg Warner rear-end, and 4 wheel disc brakes. I also just read on Wiki that 87 Irocs with a 350 did not come in t-tops because of GM was worried about the added tq with the 350. But I searched and found that they in fact did? and the GTAs did not come with t-tops so does anyone know if this is true. But anyway with this being the first year of the 350TPI and I happen to own one with every factory option. I really want to do a 383 engine build and some other things but if this car would be worth something in the next 20 years in stock form, I don't want to ruin it.

 

The 87s had barely enough torque to get moving, so I seriously doubt they had enough to tweak the body. But you could always stiffen things up with subframe connectors and strut tower braces.

 

330 ft/lbs of torque is barely enough to get moving???? I'm not saying I'm worried about it, I read on Wiki which is not a good source anyway but that 87 Irocs with the 350TPI did not come in T-tops but my 87 has a t-top and the vin shows it has a 350tpi and all the vin #'s match along with the rpo codes. Well I plan on using the holley stealth ram intake and you can't use it with a front strut tower brace whether I go with 383 or keep it stock 350.

 

the only vehicles the 350 did not come in was the convertibles. coupe and t-top were availible with a 350. if you go 383, its very expensive to upgrade everything on the tpi system. i alone am at $2000 in just fuel injection componants. i ported my intake and it is still extremely restrictive, and my engine just cant breathe over 4500 rpm. to get the most output, you will need one of the larger aftermarket intakes. you will also need a better fuel pump, larger injectors, a computer tune, and numerous chassis, drivetrain, and suspension upgrades to handle the power. lucky for you, the 9 bolt should handle a 383 as long as you dont use slicks

 

If I upgrade to 383 I'm going to with the Holley Stealth ram and the previous owner put in a walbro 255 lph fuel pump. And apparently the stock hood won't fit with the HSR so an aftermarket hood will probably be going on as well. Also sub frame connectors, all new springs, shocks and sway bars, all new gearing in the rear-end and locker, the block I was looking at comes with a new chip programmed for the 383 TPI. I will also get a built 700R4 and I realize this will be alot of money and don't expect it to get done all at once. I bought this car as project and it will probably take me at least 5-10 years. I think the first thing I'm going to tackle is the interior and get it all straightened up it's in need of TLC and then it's on to the suspension. I'm just trying to get my list of things I want/need for the car so I can put it in my spreadsheet so when it comes time to do the swap I have pretty much everything I need except the minor things. Also I noticed when I try to break the tires loose theres a popping noise coming from the rear-end I don't know if this is the stock G80 lsd locking up the rear-end or if there's something going on in the differential that isn't good or if a u joint is bad, any ideas? I haven't had a chance to put the car up on jack stands yet, but will this weekend when I change the oil. I also need to get a hood release latch as it's missing and the ebrake cable that goes to the passenger side of the rear axle.

 

the stealth ram is about the same dimensions as an lt1 intake and should clear the stock hood. the tpi setup is probably the tallest intake i have seen short of a tunnel ram. as for the popping noise, it cant be good. i would advise against driving it until you find out what is wrong

 

I can't drive it right now anyway, I can't register the vehicle till I can get it ready to pass safety inspection. And in order to do that I need a new front driver sway bar bolt, hood release cable, and passenger side ebrake cable.

 

You shouldn't have to swap hoods....find the right intake system. Cowl hoods look like crap on 3rd gens. You just need to measure measure measure to get it right. Also, you will be fine with ttops, I have a built stroker and it won't twist. Putting slicks on and drag racing it, over time, will tweak it but regular street driving won't twist it up.

 

I completely agree about cowl hoods on a 3rd gen I love the stock hood and would like to keep it all costs, everything I have read about the Holley Stealth ram on 3rd gens is that you have to remove the under hood foam and trim a little off the underside of the hood in order for it to clear the hood. I know the mini-ram clears by alot but the cost comparison between that and the HSR is tremendous and there is only a 4hp gain with the mini-ram. But the mini-ram could be it's weight in gold as I don't have to trim the hood or even put a cowl hood on the car.

 

"Cowl hoods look like crap on 3rd gens."

What?????? Not even the IROC Daytona hood you like on third gens?