383toy

I am biulding a 383 tpi that will be installed in a Jeep. My primary purpose for the vehicle is daily driver with tons of low end torque. Right now I have 9.5 - 1 compression, stock 92 camaro heads, cam, and exhaust. By design I am trying to be a little cautious with the build up because my goal is to slowly crawl over tree stumps and not race down a 1/4 mile track.

If I simply install the tpi (91 Camaro) onto the block, bearing in mind the cam and heads are stock, will I have to modify the chip or can I simply play with the fuel pressure?? I've been told the stroke has nothing to do with the computer's performance, but not convinced.

Any help would be great.

I hope it is not a problem posting this question on this site.

Mark

Grim Reaper

If it is from a 1991 TPI, then you have Speed Density. You need to tell the eprom that the engine is bigger or the ECM will not supply enough fuel (as Displacement is criteria in the SD eprom). Also, is the TPI from a 350 or a 305? What size injectors are you going to be running?

Fuel pressure will help if it is from a 350 as they have larger injectors and tend to be overly rich anyway. From my working with SD, increasing displacement to 383 from 350 would actually make if fairly close with minor tweaking to the fuel pressure. However, if it was from a 305, the injectors will probalby be too small to compensate for a 383 - too big of a change.

383toy

thnaks for the reply.

Tht tpi is in fact SD, and the package came from a 350. The injectors are 24lb.

I had the feeling I could simply increase the fuel pressure, but was not too sure.

Any suggestions on the pressure I should be using??

Mark

Grim Reaper

In all honesty, it's more of a "lucky combination" of parts. BTW, if the 383 is actually a stoked L98 TPI, you should watch your compression ratio. Stock, the 91 L98 had 9.75:1 (thanks to a thin gasket). If you use a .038 gasket instead of the thin gasket, it will help keep your compression ratio "managable". If you didn't deck the block, the compression ratio will be around 10.1:1. If you did deck the block, you may find your compression ratio too high (for the stock iron heads and cam) and find a lot of knock retard by the ECM. L98s (and LB9s) are quite prone to knock retard, a 383 can make it even worse (with the stock iron heads, etc).