Official 84 Cutlass Tpi build

[clean8485]

You would probably be wise to check the casting number on the engine block, to verify exactly what engine you have. As I said, as far as I know, the 5.7 wasn't available from the factory until 1987. I have heard rumours that there may have been a few 1986 F body cars that were built with the 5.7, but I've never seen any confirmation of this. Hope it works out OK for you.

 

[86 Grand prix]

You would probably be wise to check the casting number on the engine block, to verify exactly what engine you have. As I said, as far as I know, the 5.7 wasn't available from the factory until 1987. I have heard rumours that there may have been a few 1986 F body cars that were built with the 5.7, but I've never seen any confirmation of this. Hope it works out OK for you.

I believe you are correct. Look in the console or glove box for the L98 option but it was not supposed to have been available until 1987. 5.0 was L69. I had a 87 GTA with the 5.7 it was a fun car. So much instant torque!!!

 

[jetsetw31]

I have heard rumours that there may have been a few 1986 F body cars that were built with the 5.7, but I've never seen any confirmation of this.

To clear this up. No F body cars before late 1986 came from the factory with a L98 /5.7 TPI installed.
All the rumors were about Dealers that installed the 5.7 in the F bodies when the 5.7 crate motors were available. And even then, there were so few, that it is not worth sending anyone on a hunt for those cars. Back then if you had the cash, It could be done. If you happen to find one today, it is pure luck.

 

[Bowtieheart]

The main thing people miss / forget is that the TPI is designed and based on the 305, with its small bore and puny ports. Remember this was at a time when you had to deal with ever-tightening emissions and most manufacturers were seriously looking at downgrading engine displacement and # of cylinders (not unlike today). The entire intake system (throttle body, main plenum, intake runners and lower intake) is small in terms of flow; I mean, why have something that has hella intake flow when it will only get strangled by the small port in the head and small valve. The runner length helps make up the hp deficit, making good torque, especially on the 350.

Again, since most guys/gals don't know this they just go straight to stroking it, completing head work w/ bigger valves, put in a hotter cam and are disappointed when the engine falls on its face. The intake can't keep up with the improved breathing capability of the long-block. It's similar to when folks over or under-carb their engine, or keep a restrictive exhaust, or have a nice engine package but have a crap-tastic ignition.

Driven's statements and article link were very good and makes that point. In the article they actually explained this achilles hill and "corrected" it by extrude honing and doing some porting work on the entire system as well as going to a larger throttle body. Honestly I would do that even if I wasn't going to stroke it to a 383. I was going to suggest trying to find aftermarket runners or have the ports / runners ported. Upping the injector size may help, as well as getting the ignition in order. The stock HEI gives up the ghost around 4500 ~ 4800, same rpm the intake runs out of breath.

 

[Bowtieheart]

Had to post this here for my reference. Good info.

 

[Bowtieheart]

So I have this Camaro that I bought for parts because we believe the torque converter is bad. The car starts and idles fine but as soon as I try to shift it into reverse or drive, it shuts off. The thing is, I actually like this car also, not more than my Cutty but enough to not want to tear it apart and junk it. :? Oh well, I guess i'll get to the bottom of that in time. (Hard choices)

So I'm thinking of either starting with my exhaust or suspension. I don't know much about the suspensions on our cars nor what people recommend. As for exhaust, I really want an x-pipe with tru-duals, going into some Dynomax Vt Mufflers. The problem is, I'm not sure what size exhaust exhaust to go with since it'll be dual exhaust. I was thinking 2.5 dual but not sure. What do you guys think?

 

[jetsetw31]

2.25 is a safer bet to get the pipes tucked under the car nicely with no interference with moving parts. 2.5s work, but i have seen them get crunched under he car from bottoming. JMO. The flow is about the same with them both, unless you plan on revving past 6500 rpm. Then you will need the 2.5s or better, with headers of course. Under 5000 rpm the stock exhaust manifolds are ok for use with 2.25 on the street.

 

[Bowtieheart]

I don't see myself revving past 6200rpm unless it's to rev a little higher to keep my shifts stronger. And I do plan on Longtubes, so 2.25 duals should be fine right?

 

[crucial118]

If you ever get tired of the TPI and want something with a little more air, put on a Holley Stealth Ram. That's what I did, once my money got right, then a good cam too match. But my TPI was plenty fun on the street, with a good TPI cam for torque(Hot cam spec'd one Howards). Don't know about the track(never took it there), but definitely fun on the street.

 

[DRIVEN]

The Iroc may just have a stuck lockup solenoid. If that's what the problem is it's a cheap and easy fix. Once you are sure if it's a 5.0 or a 5.7 you can decide whether it makes sense to part it or flip it.