hi i have an 88 gta how hard is it to swap a 305tpi to a 1987 350tbi and use the tpi from the 305?because i don't want to use the tbi. it should just fit in nicely right all i would have to change would be my computer chip and match the intake ports right? or am i missing some more stuff? well any info would help alot

 

'87 350 TBI? What is this supposed to have come out of?

If it is a 350 TBI engine, the heads are terrible from a performance standpoint. No port matching required, though.

 

so should i just use the heads from my 305 and get them done up or look fo different heads?

 

You could go either way, but using your current heads and having 1.94" intake valves installed would be a good route. Most likely the 350 has dished pistons, so the smaller 305 chambers would be a nice compression bump (similar to what the 305 has now).

 

ok cool so could i get them shaved as well? that would boost up the compression a bit to right

 

did they make a big block tbi

 

No. The 58cc chambers are small enough.

Yes.

 

Yep, it was a 454. The 454 throttle body is a popular part for the 305 TBI crowd, or so I heard anyway.

 

ok so i found a 350 tbi in the paper i have to call him at 6 so i'll find out everythin. but if the 454 was the only tbi big block i should be ok

 

That 454 was a dog a** engine, and bad gas mileage to boot.

 

Yup, it was nothing impressive to say the least. Some of its parts though, like the throttle body unit, work very well on the smaller 305 and 350 TBI motors.

 

how much dose it cost to rebuild a set of heads about?

 

ok im goin to see the motor tomorrow evening probly goin to pick it up the guy says it runs great so i'll keep in touch i'll probly need help since this is my first engine swap

 

im thinkin im goin to put a bigger cam in it as well. oh yeh anyone know how much it will cost to get a new computer chip and could i use the performance chip that is on the old one in the new one or do i have to get a new performance chip too?

 

You are going to have to get a new chip. The best way is to burn them yourself which will cost about 300 bucks for all of the stuff. If not, you will have to datalog your car and send the info into a reputable burner www.tbichips.com and have them do it for you. They are only a stab in the dark at best and the only true way to get the right "right" is to do it yourself. I would put that engine aside and work on it while you learn chip burning along with what else makes TBI cars tick. You will want to change the heads and cam right away. The stock ones on that motor are pure garbage.

 

Its not all that bad! My friend has headers and alot of other stuff done to his and had 350 hp. 485 fl/lb or torque....He just put a Whipple on it and is pushin over 500 hp....Through the stock throttle body!

 

but im not keeping the tbi on it im converting it to tpi from the 305

 

I know you are, I was just commenting on someones post about 454 TBI.... In your case...Look for a thread I did a while ago about converting a 305 IROC I have to a 350 and using the 305 TPI...

 

Shifty missed that, I believe.

Learning to burn your own PROM is time and money well spent.

 

Still have I think

Anywho, five7kid is dead on about tuning. It is the lifeblood of TBI cars when you start to mod them.

EDIT: So are you going to TBI or TPI? Sorry, I am not hitting on all 8 tonight.

 

He wants to put his 305 TPI on a 350 originally equiped with TBI.

 

ok i have the engine now so what cam should i get? i want somethin with decent power all the way through the revs

 

hi will i also have to change my injectors? and if so how much do they cost about

 

The questions you're getting into now are better answered on the TPI forum (injectors) and PROM forum.

 

Decent power throughout all the rev range is gonna be difficult with a stock 305 TPI setup, Thats why I just stayed carb when I swapping my motor from my 82' in the IROC next month.