I was wondering where i can find the engine code for my 91' 305 TPI. I was also wondering if anyone knows where i can find information on that engine such as stock horsepower, torque, accel times...etc. thanks

 

the engine code is found on the RPO sricker inside your console. With tpi, it will either be LB9 (305tpi) or L98 (350tpi). The 350tpi might also be RPO code B2L.

The horesepower for the 305 will depend on if it has a single cat or dual cats. With dual cats, horsepower is 230, 200 with a single cat.

The horesepower for the 350 is 245, and all had dual cats in your model year.

I'm not sure about the torque ratings, but I believe they are 295 for the 305tpi, and 345 for the 350tpi.

You can find these ratings here:

https://www.thirdgen.org/newdesign/tech/techdb.shtml

Sorry if the link does not work, it is my first time trying that.

 

i checked out the rateings from that link you gave me. there are two sections for the LB9 V8 305. one is rated at 205hp and the other at 230hp. is that because the offered two types of 305's that year? i believe they offered a little more horsepower with the ws6 but i am not certain. how can i tell which engine i have. its a 91' formula auto if that helps. thanks

 

The actual motor itself is the same.

The difference is the G92 RPO, which is dual cats. If you have that, then you have the 230 HP version. Single cat = the 205 HP one.

Has nothing to do with suspension option packages such as WS6.

 

I see what you mean. So if i rip off my exhaust and start over from the block back with headers and run dual cats and true dual exhaust all the way back i should be able to regain those 25 lost hp right? if not gain a little more. that single cat/muffler with the dual exit ports is a rip, its kinda robbing me of 25hp right? thanks

 

It's the factory Y-pipe and single cat. Not the muffler. And not necessarily a replacement high-flow cat.

The G92 cars had 2 cats, but still had only 1 I-pipe and one muffler. The same muffler as the other AFAIK.

 

but if i do start over from the block back should i gain back those 25hp?

 

Possibly. That would depend on what you put there.

"True dual" exhaust is not necessarily a good idea on these cars. It doesn't fit the car well, unless you make the pipe so small as to lose the advantage of having 2 of them; or unless you are willing to deal with very poor ground clearance; or you do the old 70s high-school hilljack thing and jack the rear end of the car up.

Look at it this way: the LS1 cars are making near 400 HP at the crank, with a single exhaust, very much like the ones that come in these cars. I doubt your 305 TPI, that makes a little over half that much power, will need more exhaust than that.

I'd suggest a good quality set of chassis-specifc headers, such as SLP or Edelbrock TES; get the ones for a 350 if you think you might improve your engine's size someday; get a good quality high-flow cat such as a Catco, Car Sound, etc; and one of the pre-packaged cat-back exhaust systems that are available from any number of mfrs. Don't get cheap headers, they're no bargain. And don't hallucinate that a muffler shop is going to be able to bend you up a sysem that will work anywhere near as well as, let alone better than, a manufactured exhaust; or that it will fit as well; or that you will "save" money by going that route.