We all know that car companies under estimate an engines " real/true" horspower ratings due to insurance reasons.. My question is, does anyone have an idea of the "true" horsepower rating of 350 tpi engine(L98) out of an 89 formula?

 

Actually, the current "net" ratings are much more accurate than what the factories said in the 60's.

Single cat L98 230 HP, dual cat L98 240 HP.

Now, if you want a "gross" flywheel HP number, take it to an engine dyno, use an electric water pump, long tube headers, and let 'er wail. You'll probably come up with something like 275-285 HP.

 

If you run the actual performance figures for these cars through the various calculators the factory ratings are pretty close.

 

Dumb question but I need ask so I will know,lol. L98 motors are just 350s from around the 80s and 90s right? Before the 80s or so did they had a different name? I ask because I have a mid 70s 350 block and didn't know what that motor might be called or if it was also a L98?

Don't mean to hijack the thread but seemed like a good place to jump in...

 

No, an L98 is a 350 with TPI. They didn't exist before 1985, or after 1992.

 

There are a lot of 350 engines produced by GM. There are many variations of them with compression ratio, cam grind, induction systems. All of these get a specific engine code. The late 80's 350 TPI engine was classified as an L98. A mid 70's 350 usually had a L82 or L48 engine code and there were many others. The 1970 Corvette 350 got an LT1 engine code.

 

ah, ok. I understand how the engine codes work now. I'll take a peak at my block again sometime and figure out what mine was. Thanks for explaining

 

That's also why it doesn't matter what an engine used to be, or what platform it was installed in, or how much power it used to make. As soon as you pull it out and take away some of it's factory-installed equipment it stops being what it was and becomes just another 350, or whatever.