I recently bought an 89 Trans Am. The car has the original 305 and it is automatic. I got a great deal on the car but I'm not too impressed with the motor. I would like a 5.7 TPI. I was wondering what the most cost effective/easy way to do this would be? To take a 350 block and put my TPI from my 305 on it, or go to a junkyard and find a 5.7 TPI? The most I'm willing to spend on the engine itself is about 2,000.00
please help.
Thanks
Josh
please help.
Thanks
Josh
five7kid
Moderator
close
May 4, 2026
Get a 350 long block, '87-up style, and an adjustable fuel pressure regulator. Put your 305 TPI on it, adjust the fuel pressure to make it run right. Eventually, you may want to consider 22 lb injectors (the only difference between 305 & 350 TPI's along with fuel pressure setting).
Consider exhaust upgrades (headers, high-flow cat & catback), which would even help your 305.
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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R4. 2.93 limited slip. Cat-back from '91 GTA, ZZ3 intake, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/'87 LB9 block, ZZ3 cam, ported World 305 heads, Hooker headers & y-pipe, 3" Catco cat & 3" cat-back).
57 Bel Air, my 1st car. '66 396, 9.7 CR forged TRWs, Weiand Action+, Edelbrock 1901 Q-Jet, GK 270 cam, Magnum rockers, Jacobs Omnipack, 1-3/4" Hedders & 3" Warlocks, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, MegaShifter, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Idles smooth @ 600 RPM in D. Best 15.02/95.06 @ 5800' Bandimere (corrected 13.93/102.4 @ sea level).
Consider exhaust upgrades (headers, high-flow cat & catback), which would even help your 305.
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82 Berlinetta, orig V-6 car, now w/86 LG4/TH700R4. 2.93 limited slip. Cat-back from '91 GTA, ZZ3 intake, Accel HEI SuperCoil. AMSOIL syn lubes bumper-to-bumper. Daily driver, work-in-progress (LG4 w/'87 LB9 block, ZZ3 cam, ported World 305 heads, Hooker headers & y-pipe, 3" Catco cat & 3" cat-back).
57 Bel Air, my 1st car. '66 396, 9.7 CR forged TRWs, Weiand Action+, Edelbrock 1901 Q-Jet, GK 270 cam, Magnum rockers, Jacobs Omnipack, 1-3/4" Hedders & 3" Warlocks, TH400 w/TCI Sat Night Special conv & Trans-Scat shift kit, MegaShifter, 3.08 8.2" 10-bolt w/Powertrax, AMSOIL syn lubes bumper-to-bumper. Idles smooth @ 600 RPM in D. Best 15.02/95.06 @ 5800' Bandimere (corrected 13.93/102.4 @ sea level).
Supreme Member
find a used 3.8 turbo motor
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87 trans am,gm crate 350(4 bolt mains 10to1),L98 aluminum heads,LT4 hot cam,slp runners,slp 1 5/8 headers,3in.y-pipe,edelbrock base,hi flo cat,air foil,afpr,as&m ported plenum,gutted airbox,t-5 tranny w/centerforce clutch and a 3.27 9bolt(11.9in. brakes),ed wright's fastchip,relocated iat sensor,160 fan switch&t-stat,tb bypass,accel supercoil,cap& rotor,hollowed maf,slp 3in. catbcak.
FOR SALE!FOR SALE!FOR SALE!FOR SALE!FOR SALE!
EVRYTHING IS FOR SALE WITH MY CAR (EXTRA ENGINE,TPI INTAKES,RUNNNERS,PLENUMS,ECM W/CHIP,new springs,aluminum driveshaft.
GETTING OUT OF THE 3RD GEN MARKET BEST OFFERS
CONSIDERED!!!!!!!!!!!
anyonne from new jersey interested??????
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87 trans am,gm crate 350(4 bolt mains 10to1),L98 aluminum heads,LT4 hot cam,slp runners,slp 1 5/8 headers,3in.y-pipe,edelbrock base,hi flo cat,air foil,afpr,as&m ported plenum,gutted airbox,t-5 tranny w/centerforce clutch and a 3.27 9bolt(11.9in. brakes),ed wright's fastchip,relocated iat sensor,160 fan switch&t-stat,tb bypass,accel supercoil,cap& rotor,hollowed maf,slp 3in. catbcak.
FOR SALE!FOR SALE!FOR SALE!FOR SALE!FOR SALE!
EVRYTHING IS FOR SALE WITH MY CAR (EXTRA ENGINE,TPI INTAKES,RUNNNERS,PLENUMS,ECM W/CHIP,new springs,aluminum driveshaft.
GETTING OUT OF THE 3RD GEN MARKET BEST OFFERS
CONSIDERED!!!!!!!!!!!
anyonne from new jersey interested??????