305 Tbi to 350 TPI
Thread Starter
Joined: Dec 2008
Posts: 2,540
Likes: 0
From: Norwalk, CA
Car: 91Z28
Engine: 5.7 ls1
Transmission: 4l60e
Axle/Gears: 3.42
305 Tbi to 350 TPI
Hello there i just bought a 91 RS this weekend for I could build during this year to have it ready by next summer, it now has a 305 tbi in it and i am gonna buy another transmission this december. Also I was wondering since i have a 350 tpi i bought before I bought the car and i have rebuild that engine and was wondering how hard would it be to put the tpi into my car. I have the wiring harness and the ecm but i don't know if it has all the sensors. Would it be expensive to do or should I just stay with tbi to not go through all the struggle so i have about a year to think about it so i would appreciate any recommendations you guys give me. I also have no experience on engine swaps since i am only 17, but i am a fast learner if any of you live by Los Angeles and could help please tell me
Joined: Jan 2002
Posts: 3,449
Likes: 7
From: LONDON, KY
Car: Camaro
Engine: Carbed L98
Transmission: TH350
Axle/Gears: 3.73
Re: 305 Tbi to 350 TPI
Is the TPI Speed Density or MAF?
You should be able to just swap the harness and ecu. Thens its plug everthing in.
You will have to change the fuel pump out to a TPI higher flowing unit.
You should be able to just swap the harness and ecu. Thens its plug everthing in.
You will have to change the fuel pump out to a TPI higher flowing unit.
Thread Starter
Joined: Dec 2008
Posts: 2,540
Likes: 0
From: Norwalk, CA
Car: 91Z28
Engine: 5.7 ls1
Transmission: 4l60e
Axle/Gears: 3.42
Re: 305 Tbi to 350 TPI
I think its MAF not sure, so i could just swap it then because i have read in places that you need to have same wiring harness as the car. Do you know how i could check if its MAF or Speed Density?
Joined: Jan 2002
Posts: 3,449
Likes: 7
From: LONDON, KY
Car: Camaro
Engine: Carbed L98
Transmission: TH350
Axle/Gears: 3.73
Re: 305 Tbi to 350 TPI
SD had the map sensor like your 92 TBI which should be mounted on the firewall close to the dist. A MAF system will have a "Mass Airflow Sensor" located in the ductwork between the filters and the TB.
I swapped from a 89 TBI to a 92 TPI sd. I changed the dash and all the wiring under the hood at the same time as the motor. You should be able to find some writeups on the MAF to SD conversion.
Try this link. http://www.eecis.udel.edu/~davis/z28/ecm_swap_730/
I swapped from a 89 TBI to a 92 TPI sd. I changed the dash and all the wiring under the hood at the same time as the motor. You should be able to find some writeups on the MAF to SD conversion.
Try this link. http://www.eecis.udel.edu/~davis/z28/ecm_swap_730/
Thread Starter
Joined: Dec 2008
Posts: 2,540
Likes: 0
From: Norwalk, CA
Car: 91Z28
Engine: 5.7 ls1
Transmission: 4l60e
Axle/Gears: 3.42
Re: 305 Tbi to 350 TPI
I think i remember the guy who i bought if from tell me that he tuned the computer for it could have the con filter on it. Also when you did the swap only the engine wiring harness or no, because they say you could put a new harness in a old car but that you cant put a old harness in a newer car is that true.
Thread Starter
Joined: Dec 2008
Posts: 2,540
Likes: 0
From: Norwalk, CA
Car: 91Z28
Engine: 5.7 ls1
Transmission: 4l60e
Axle/Gears: 3.42
Trending Topics
Joined: Jan 2002
Posts: 3,449
Likes: 7
From: LONDON, KY
Car: Camaro
Engine: Carbed L98
Transmission: TH350
Axle/Gears: 3.73
Re: 305 Tbi to 350 TPI
I think i remember the guy who i bought if from tell me that he tuned the computer for it could have the con filter on it. Also when you did the swap only the engine wiring harness or no, because they say you could put a new harness in a old car but that you cant put a old harness in a newer car is that true.
Thread Starter
Joined: Dec 2008
Posts: 2,540
Likes: 0
From: Norwalk, CA
Car: 91Z28
Engine: 5.7 ls1
Transmission: 4l60e
Axle/Gears: 3.42
Joined: Jan 2002
Posts: 3,449
Likes: 7
From: LONDON, KY
Car: Camaro
Engine: Carbed L98
Transmission: TH350
Axle/Gears: 3.73
Re: 305 Tbi to 350 TPI
If its a 87 then it came out MAF. Unless he did a swap to SD.
Im not sure, but maybe just a ECM change and adding a MAP sensor and some wiring. Maybe someone else that has done the MAF to SD swap can chime in. Or do a search on the swap.
Im not sure, but maybe just a ECM change and adding a MAP sensor and some wiring. Maybe someone else that has done the MAF to SD swap can chime in. Or do a search on the swap.
Thread Starter
Joined: Dec 2008
Posts: 2,540
Likes: 0
From: Norwalk, CA
Car: 91Z28
Engine: 5.7 ls1
Transmission: 4l60e
Axle/Gears: 3.42
Re: 305 Tbi to 350 TPI
I found this place were th guy could convert my tbi harness to tpi for $250 $75 for a 90-92 ecm and $189 for a custom prom what else would i need other than that to do the swap
Joined: Jan 2002
Posts: 3,449
Likes: 7
From: LONDON, KY
Car: Camaro
Engine: Carbed L98
Transmission: TH350
Axle/Gears: 3.73
Thread Starter
Joined: Dec 2008
Posts: 2,540
Likes: 0
From: Norwalk, CA
Car: 91Z28
Engine: 5.7 ls1
Transmission: 4l60e
Axle/Gears: 3.42
Re: 305 Tbi to 350 TPI
Doesnt the tpi have that already or not. When you did that swap how much did you spend on doing the swap almost $1000 or way less
Joined: Jan 2002
Posts: 3,449
Likes: 7
From: LONDON, KY
Car: Camaro
Engine: Carbed L98
Transmission: TH350
Axle/Gears: 3.73
Re: 305 Tbi to 350 TPI
The MAP sensor for a 91-92 SD TPI is mounted on the plenum now that I think of it. Back by the fpr and dist. You might use the TBI MAP sensor.
I bought a parts car for 1K. It had motor/trans/rear/interior/ground f/x and the hatch with the hi rise wing. The hood blisters were also salvagable.
It was hit in the front, but from the doors back was in perfect shape. The previous owners junked/scrap the title or I would have fixed it.
I bought a parts car for 1K. It had motor/trans/rear/interior/ground f/x and the hatch with the hi rise wing. The hood blisters were also salvagable.
It was hit in the front, but from the doors back was in perfect shape. The previous owners junked/scrap the title or I would have fixed it.
Thread Starter
Joined: Dec 2008
Posts: 2,540
Likes: 0
From: Norwalk, CA
Car: 91Z28
Engine: 5.7 ls1
Transmission: 4l60e
Axle/Gears: 3.42
Re: 305 Tbi to 350 TPI
You were lucky to find it like that because i am searching for one like that but they are not close by were i live or do you think i should just go with carburator.
Joined: Jan 2002
Posts: 3,449
Likes: 7
From: LONDON, KY
Car: Camaro
Engine: Carbed L98
Transmission: TH350
Axle/Gears: 3.73
Re: 305 Tbi to 350 TPI
You need to learn how to burn you own proms. There is plenty of info on the board. Most members are willing to help or walk you through it.
Thread
Thread Starter
Forum
Replies
Last Post










