Is it possible to turbocharge my 305TPI? I'm thinking about buying a Garrett TP38. What would I have to do to the engine itself and how much power can I expect?Need info ASAP please!

 

You can turbocharge any automotive engine up to and past it's structural limits. The stock 305 can take a mild turbo boost without any internal modifiactions. Make sure the AFR is safe and there is no detonation, and you could get 400hp out of it without opening it up. Having the proper AFR and spark timing is half the battle in making a powerful and reliable turbo car.

 

Would it be possible to turbo a stock 305TPI? If so, how much boost and power could I make?

 

Yes, you can turbo a stock 305, thats what I was trying to say in my first post. How much boost/power it can take is going to depend on how far you want to push the limit of reliabilty and how good you are at tuning the combo. I will say 350 hp at around 6psi of boost should be very reliable (and quite fast). Push the limits a little further, and 400ish HP should be attainable at around 10psi of boost. If its still holding up and running well, a few runs down the track with even more boost will go even faster if you have the fuel system mods to support it, but you will be pushing the reliabilty limits. These numbers are just my educated guess, but I do have experience turboing the stock TPI (mine is the 350 L98, but you can overcome the displacement deficiency with boost).

You should get similar power results as those with centrifugal superchargers. Maybe someone else will chime in with their results of boosted stock 305s.

Make sure you do plenty of research before you dive into turbocharging. It's not that hard, but you have to know what you are doing and pay attention. Read the books (both of them!) listed in the sticky at the top of this power adder board.

 

Would 6 psi be safe and reliable on the 305?Also I'm getting ready to swap in a T-5, would it be able to take a turbo? Oh and did you mean 350HP to the crank or wheels?

 

Yes, I think I said above that 6psi on the stock 305 would be reliable. With a totally stock 305, 6psi should get you 350hp to the crank, 325 or so at the wheels. FWIW, I dynoed my TT 350 TPI on a hot day (outside dyno) and it came up with 328RWHP, 467RWTQ. This was with restrictive turbos that cost me some top end power, which is why my HP was so much lower than the TQ. Plus, the stock TPI is tuned for massive low end power. So an honest 350HP at the crank is going to be a fast car. Snce this dyno pull, I have upgraded the turbochargers, which should give me more top end (and a much higher HP rating).

The stock T5 is notoriously weak. I have a Tremec TKO behind my TT 350. You may want to go with the T56 6-speed swap instead. If you get over 450lb-ft of torque to the rear wheel like I did, the T5 may give you trouble (especially with sticky tires and aggressive driving).

 

How much torque could I expect at 6psi?

 

450lb/ft at the crankshaft, again just an educated guess.

 

hey man, im kind of in a bind as to what i want to do to my car power wise. i want to get my car somewhere on the lines of 250 to 300 HP to the wheels. now the two options that i am juggling are geting a 350 and trying to get those numbers out of it or turboing my 305. im trying to figure out which one would be more cost effective for what i want. ive been trying to find this out but no one seems to want to answer that question. so since you know what you are talking about i thought i would ask you.