350 tbi swap into 89 Firebird
#1
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Car: 1989 Pontiac Firebird Formula
Engine: 5.7L TBI
Transmission: t-5 from 85 T/A
350 tbi swap into 89 Firebird
Hello. I have a 350 tbi engine out of a 95 chevy silverado. It looks like it should mount right up but I was wondering for any advice about anything I might need to swap over also. I have the silverado so I can take any parts I need to from it. The car the engine is going into is a 89 Firebird Formula that had a 305 tbi until heads cracked. Thank you in advance.
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Car: 91 formula ws6
Engine: 355 tpi OBDII
Transmission: 4l60E
Axle/Gears: 2.73 with 4th gen brakes
Direct drop in, need to have a 350 chip tho. The 95 pcm isn't the same unless you swap the harness and pcm. Other slight differences
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Car: 1989 Pontiac Firebird Formula
Engine: 5.7L TBI
Transmission: t-5 from 85 T/A
Re: 350 tbi swap into 89 Firebird
Yeh, I have everything. Just didn't know if factory computer would hook up
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Car: 91 formula ws6
Engine: 355 tpi OBDII
Transmission: 4l60E
Axle/Gears: 2.73 with 4th gen brakes
No. Some guys were swapping the pcms into our cars in the past but I've been out of the TBI game awhile
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Car: 1989 Pontiac Firebird Formula
Engine: 5.7L TBI
Transmission: t-5 from 85 T/A
Re: 350 tbi swap into 89 Firebird
So I swapped the engine out with the 350. I used the 305 harness and pcm. Then I used everything connected to the engine (intake, sensors) and put it in. The only thing I found is that I used the 305 tranny and it didn't take the extra power. And I found that the Alternator mount actually sat higher relative to the engine so if I stepped on it hard, the Alternator would vibrate against the hood. Since the tranny went, I went forward and bought a parts car to throw a t5 transmission into it. Now I can spin tires up through the first 3 gears. During a dry day!!! Very excited. Should anyone have any questions after I post this reply, feel free to pm me. Thanks everyone who helped and sent me a reply.
#7
Re: 350 tbi swap into 89 Firebird
Hello. I have a 350 tbi engine out of a 95 chevy silverado. It looks like it should mount right up but I was wondering for any advice about anything I might need to swap over also. I have the silverado so I can take any parts I need to from it. The car the engine is going into is a 89 Firebird Formula that had a 305 tbi until heads cracked. Thank you in advance.
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#8
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Car: 1986 Iroc
Engine: 5.3
Transmission: 4L80E
Axle/Gears: 9 Inch w/ 3.55
Re: 350 tbi swap into 89 Firebird
So why do you need to swap spark control module if you get a custom chip?
#9
Re: 350 tbi swap into 89 Firebird
a chip will change your timing, advances it, which makes the engine run a bit warmer so they tell you to put in a cooler thermostat. You can also advance the timing with the engine not running, it will stay advanced. Your car shuts down at 110 mph, it's not recommended, but you can run a switched wire to the fuel pump relay, it won't shut down at 110. So what is your question about the chip?
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Car: 1986 Iroc
Engine: 5.3
Transmission: 4L80E
Axle/Gears: 9 Inch w/ 3.55
Re: 350 tbi swap into 89 Firebird
a chip will change your timing, advances it, which makes the engine run a bit warmer so they tell you to put in a cooler thermostat. You can also advance the timing with the engine not running, it will stay advanced. Your car shuts down at 110 mph, it's not recommended, but you can run a switched wire to the fuel pump relay, it won't shut down at 110. So what is your question about the chip?
#11
Re: 350 tbi swap into 89 Firebird
So I swapped the engine out with the 350. I used the 305 harness and pcm. Then I used everything connected to the engine (intake, sensors) and put it in. The only thing I found is that I used the 305 tranny and it didn't take the extra power. And I found that the Alternator mount actually sat higher relative to the engine so if I stepped on it hard, the Alternator would vibrate against the hood. Since the tranny went, I went forward and bought a parts car to throw a t5 transmission into it. Now I can spin tires up through the first 3 gears. During a dry day!!! Very excited. Should anyone have any questions after I post this reply, feel free to pm me. Thanks everyone who helped and sent me a reply.
#13
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Car: '88 IROC-Z
Engine: 305 TBI
Transmission: 700R4
Axle/Gears: 2.73
Re: 350 tbi swap into 89 Firebird
I'm swapping a 88 305 TBI out for 88-89 350 TBI in an 88 IROC. So ECM is to be changed or can u get 305 upgraded? (chipped). What else to make this transition easy. I've read knock sensor. Any help would be appreciated.
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Car: 1989 Pontiac Firebird Formula
Engine: 5.7L TBI
Transmission: t-5 from 85 T/A
Re: 350 tbi swap into 89 Firebird
Sorry, you probably got all your info but figured I'd reply. Ive read you can change the ecm or get it chipped but I'm running a good a/f ratio with my stock ecm. As long as you make sure to use the intake from the 350 so it has the bigger tbi and injectors.
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Car: 1990 GMC Suburban 4x4
Engine: TBI 350
Transmission: 700R4
Axle/Gears: 3.55
Re: 350 tbi swap into 89 Firebird
Solid motor mounts- or a chain to the frame on the driver side to hold it from moving! Poly mounts might keep it from hitting too.
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