I am going to be buying all the parts for the TBI to TPI swap in about a month and I want to make sure I have all of my best ducks in a row. I am looking to see opinions on the following setup, how much HP I should pick up over TBI, and any changes you would make?

Ported stock plenum
TPIS Big mouth intake
AS&M Semi-Siamesed runners
24lb FMS injectors
52mm BBK throttle body
Speed Density setup
SLP Airfoil
Normal TPI fuel rails
Custom Tuning

This is going to be a complete forged buildup, new cam, pocket ported SR torquers, SLP headers, dual cats, full exhaust (the works) and I have already contacted ATI about getting me an intercooled D-1 to throw on there. I just want to see what kind of HP I am looking at for the above over the TBI (stock to stock numbers) and if the above will be sufficient enough for the proper SC situation.

Thanks

James

 

throwing tpi with a few extras on top of a stock L03 long block might yield you around 30 or so hp. I assume you are going to be doing this future "build-up" on a 350, as you are throwing money away on that old 305 with the stuff you are talking about doing. i'll tell you this, in N/A form the LTR setup is going to top out around 350 hp. This limit of course will be raised significantly with forced induction, but then again i don't really know what kind of power you are looking for, so i can't really tell you if tpi will be enough.

 

Didn't post more because my buildup is not a popular idea, but here you go.

305 stroker to 335 - Forged version makes 335, not 334, at least that's what TRW says. Compression ratio is going to be 9:1, yes there is going to be a ATI procharger. Still working on that detail (D-1, P1sc, etc...) dependent on the boost that I want to run.

No, I'm not throwing money away, but I am also not building a 350. I will have gas mileage and performance. Something the 350 cannot give me. 350 will give more horsepower yes, but not the same gas mileage. In the same note a 502 will blow away the 350, but than again I wont get gas mileage there either

Spec for spec you are looking at all around better engine, IMO for my application. I am not running down the 1/4, I am in a vert for g*d's sake lol but being able to kill the local honda civic (I live in southern california) is a very nice thing and getting to vegas faster is my main concern. Not running 10's, 11's, or even 12's in the 1/4 mile. I still think I can get a bit lower compression, but 9:1 will be perfect for pump gas, no timing retarding with the intercooler, etc...

Also I think a built TPI should get a lot more than 30hp if the 305TPI stock had 45 more hp than the TBI, I was thinking more in the 60-70 range. L03 is at 170, with the later TPI being 215 (maybe 205, cant recall) The LB9 came out at 195 - 230hp dependent on the tranny and car. So 25 - 60hp.

After reading some of the boards guys with the above mods I mentioned were claiming 20-40 horsepower over their stock TPI dependent on who you talked to and the other mods they had already done. I also know that they had different heads and a different cam, but I am changing all of that anyway. Also the cam is probably a Crane 2032 hydraulic roller Compucam going in.

What I would like to know is if that is the best TPI system you could build OR if something like a Superram is a better avenue. Considering I have to change everything anyway and keep emissions legal.

James

 

With all the work you plan on doing, you could drop in an LT1 and still get 28+ MPG. 350's arent the gas hogs that folks think. Hell, my LT1 gets 4MPG more than my 305 TPI on the highway, albeit I haven't enabled highway mode yet. Your combo sounds cool though, and I like the dare to be different approach. Good luck.

 

ZZ - I was considering the LT1/LS1, but I want AC and I haven't seen any one that has gotten the AC to work on the LS1, and the ones that got the LT1 to fit all the clearances were very close, and the AC had to be custom made. Changing plugs is hard now I cant even imagine with an LT1 or LS1 lol

A 305 I am confident that I can take it out of the car, have the bottom end built, build the top end and reinstall. I have done it on several boats which is a bit different, but in most cases is actually much harder. Out drives are a pain and direct drives are worse.

Also to me saying that I have a blown and stroked 305 is about as cool as saying I have a LS1, plus I will have more HP. Of course stroking a LS1 to a 382 would be sweet as well...

Now you got me thinking again.... Ugh... I have the money and need to make a decision.

James

 

i would go with an www.lt1intake.com intake insted of a long tube runner setup.
it will be cheaper and that stroker motor will breath better up in the higher RPM's

 

He has to keep emissions legal.

 

With forced induction, the LTR runner system will do fine.

 

John I really wanted to buy an LT1 intake from you But da*n California and their emissions laws. My aunt owns a home in hawaii, I may register the next camaro there, drive it here, and build a LT1 intake 383

As long as everyone agrees that the above setup is the best I can go for the TPI (and still be emissions legal) with the procharger I will start buying this week.

James

PS thanks to everyones help on this one. All of my research was done on this site to come up with the above combo.