305 TBI to 350 TBI....Anybody done this before?
#16
Re: 305 TBI to 350 TBI....Anybody done this before?
Originally Posted by TheNovaMan
How does the Caprice chip differ from a regular 350 TBI chip?
#17
[QUOTE=cas0484;3707025]I did this swap with my old 91 RS and it was pretty straightforward, the intake manifold and TB bolt up no problem. You will need bigger injectors, a different ESC module, tuning and a knock sensor. However, don't throw a Lo5 in there thinking it will be a beast....cause it just wont. Might as well throw a good set of heads and cam in there while you are at it, the Lo5 still has the crappy swirl port heads. GMPP makes a 350 H.O. that is rated at like 330hp and makes a nice home in a thirdgen. It ahs vortec heads though so you'll need a special manifold in order to keep TBI. Of course, you could always ditch the TBI for a carb or whatever you want.[/QUO
I have a 1991 RS with the 305 and want to do the 350 swap.
How much better was the 0-60 mph with the 350 compared to the old 305? Will the GMPP 350 H.O. with the 305 tb work with bigger injectors? What chip or esc would I need to get it running right and would it still pass smog in CA?
I have a 1991 RS with the 305 and want to do the 350 swap.
How much better was the 0-60 mph with the 350 compared to the old 305? Will the GMPP 350 H.O. with the 305 tb work with bigger injectors? What chip or esc would I need to get it running right and would it still pass smog in CA?
#18
Good look trying to do anything in Cali and getting it to pass smog...especiallky a motor swap. Although, if you keep the TBI and leave on the snorkel on the new 350, visually they are identical. When I swapped from the Lo3 to the Lo5 I noticed a fairly decent difference in the 0-60 and overall power of the motor compared to the 305 but the lo5 isnt anything special. I think the horsepower difference is like 170 compared to 210 so its not night and day but def noticeable. I also swapped out the 2.73's to 3.42 in the back at the same time I did the motor swap so acceleration is hard to judge just off of the motor. If you're going to do the swap, I suggest throwing something more powerful in there. With the vortec motor, the special mainfold required for it requires the bigger TB and injectors. I actually have the Holley TBI for sale if you are interested.
#19
Good look trying to do anything in Cali and getting it to pass smog...especiallky a motor swap. Although, if you keep the TBI and leave on the snorkel on the new 350, visually they are identical. When I swapped from the Lo3 to the Lo5 I noticed a fairly decent difference in the 0-60 and overall power of the motor compared to the 305 but the lo5 isnt anything special. I think the horsepower difference is like 170 compared to 210 so its not night and day but def noticeable. I also swapped out the 2.73's to 3.42 in the back at the same time I did the motor swap so acceleration is hard to judge just off of the motor. If you're going to do the swap, I suggest throwing something more powerful in there. With the vortec motor, the special mainfold required for it requires the bigger TB and injectors. I actually have the Holley TBI for sale if you are interested.
I think I'll pass on the engine swap, drive my 91 RS till it quits (260,500 miles on the original engine and trans), sell it as is and eventually buy a 91 ZX with all the mods and smog adjustments already done. That would be much easier and alot less hassle, even if costs me a little more it's worth it.
Last edited by arnold; 02-09-2007 at 02:14 AM.
#20
I did this swap myself a few years ago. Most of the stuff has been covered by those on here. I got my motor from http://www.goautocenter.com (the 350 TPI one with the TBI cam and aluminum heads installed), but I've also heard some great things about the engine the http://www.xtremefi.com sells as well.
#21
Its easier to pass smog in CA than you think. The biggest problem is the visual. As long as you keep everything emissions related on the vehicle, there are lots of head and cam combos that pass the emissions test cleaner than stock, my own combo included. But I'm TPI. The biggest problem with TBI is the slow computer and the limited number of things you can change to make it happy with a big camshaft.
#22
What's wrong? Because spending the same amount of money you'd be faster in a regular SBC. An LT1 is just a SBC with handicap in terms of price and heads/intake/block availability. Reverse flow is nice, but optispark isn't.
#24
Re: 305 TBI to 350 TBI....Anybody done this before?
these guys are leading you in the right direction. i just bought a 89 camaro rs 305 tbi i was planning on eventually doing this swap also sounds like a pain in the *** with all the wiring to go to a 350 tpi. I recently had a programmer chip the ecu for the 305 tbi that plugs right into ecu in which he removed the (vats) (Vehicle anti theft system) you will notive theres a chip inside your key thats what thats for so the car wont star and shut off fuel to injectors which sometimes they go bad and that happens is what i am told. So i had that removed and a couple other things like the smog bs and im putting exhaust and headers on it anyway to make a long story short. Your going to need a moates g1 adapter for the moates website for the TPI ECU for it to work to removed vats. I'm not sure if you can just keep the stock ecu and repin it for 350 and just go ahead a program it for a 350 tbi or tpi instead of 305tbi thats something im not sure about yet which i would like to know. ill talk to the guy i bought the chip from and ask him about it he did tell me that the caprice was the only car 350 with tbi i know that. because he did a damn good job on burning me a chip for my 89 camaro rs 305 tbi and it runs great. Just be careful with the chip it only goes in one way and theres a black plastic holder for the chip that needs to be connected to new chip you can get old chip out by bending each pin slightly and then press the bottom of chip for it to pop out and install new one. make sure you put the notch on the plastic piece with the notch on the chip on the same sides then install the plastic piece with chip with the letters on it facing towards drivers side when pushing in ecu when you pull it down and unscrew the 2 7mm bolts. Im not sure if the tpi ecu is different i never messed with tpi ecu and im new to camaro's but trying to learn as much as possible about them. i used to have 2 foxbodys. if you got any more questions message me at camaro89rs305@hotmail.com or on here
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