LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearance!
Thread Starter
On Probation
Joined: Mar 2010
Posts: 466
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Car: 1989 Formula,1991 z28
Engine: 400 Vortec Hsr,496bbc
Transmission: TKO600,TH400
Axle/Gears: 9"4.10, 9"3.73
LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearance!
heres some pics to show what my issue is...
before ya'll say flip the rails around and run them like holley suggest's..it aint gonna happen..i like how i have them routed, and fuel lines are already made and routed!
having looked at the IAC housing on the LT1 throttle bodys, it looks like the IAC motor is much shorter, and the connector faces FORWARD instead of pointing to the pass side.. looking at pictures, it looks like the LT1 iac, will bolt directly to a TPI tb..anybody tried this?
heres the issue im running into.




and an overall shot cuz its SEXY! haha

before ya'll say flip the rails around and run them like holley suggest's..it aint gonna happen..i like how i have them routed, and fuel lines are already made and routed!
having looked at the IAC housing on the LT1 throttle bodys, it looks like the IAC motor is much shorter, and the connector faces FORWARD instead of pointing to the pass side.. looking at pictures, it looks like the LT1 iac, will bolt directly to a TPI tb..anybody tried this?
heres the issue im running into.




and an overall shot cuz its SEXY! haha

Re: LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearanc
This is an interesting question. If we could prove this works that will give us an option to make working on the TPI even easier.
Thread Starter
On Probation
Joined: Mar 2010
Posts: 466
Likes: 0
Car: 1989 Formula,1991 z28
Engine: 400 Vortec Hsr,496bbc
Transmission: TKO600,TH400
Axle/Gears: 9"4.10, 9"3.73
Re: LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearanc
Joined: Jun 2004
Posts: 914
Likes: 29
From: Las Vegas
Car: '88 Trans Am
Engine: 5.7L TPI
Transmission: Slushbox
Axle/Gears: 3.27
Re: LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearanc
just in case you dont find one, i found a few decent priced units..
http://cgi.ebay.com/ebaymotors/LT1-t...Q5fAccessories
http://cgi.ebay.com/ebaymotors/LT1-t...Q5fAccessories
http://cgi.ebay.com/ebaymotors/Chevr...Q5fAccessories
http://cgi.ebay.com/ebaymotors/LT1-t...Q5fAccessories
http://cgi.ebay.com/ebaymotors/LT1-t...Q5fAccessories
http://cgi.ebay.com/ebaymotors/Chevr...Q5fAccessories
Thread Starter
On Probation
Joined: Mar 2010
Posts: 466
Likes: 0
Car: 1989 Formula,1991 z28
Engine: 400 Vortec Hsr,496bbc
Transmission: TKO600,TH400
Axle/Gears: 9"4.10, 9"3.73
Re: LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearanc
just in case you dont find one, i found a few decent priced units..
http://cgi.ebay.com/ebaymotors/LT1-t...Q5fAccessories
http://cgi.ebay.com/ebaymotors/LT1-t...Q5fAccessories
http://cgi.ebay.com/ebaymotors/Chevr...Q5fAccessories
http://cgi.ebay.com/ebaymotors/LT1-t...Q5fAccessories
http://cgi.ebay.com/ebaymotors/LT1-t...Q5fAccessories
http://cgi.ebay.com/ebaymotors/Chevr...Q5fAccessories
looking them over, my 89 formula seems to have the 85-88 style cable..but, i HIGHLY doubt its ever been changed...
i had planned to swap to the "89-97" style late model tpi/lt1 cable setup, and just use the LT1 throttle body, but the lt1's style TPS puts the sensor right on top of the fuel rail haha...i cant win for anything here!
but luckily, it looks like the LT1 iac will bolt to the tpi TB..with any luck! for the better anyways, the LT1/LS1 style IAC motor is far superior!
Re: LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearanc
Plug the end of the rail to run the injectors in series. It will clear
The LTx IAC housing swaps over just fine, but be aware the newer unit requires a new plug and has a different operating range than the stocker. Read about it in the OBDII TPI sticky. It will work, but operation will never be perfect
The LTx IAC housing swaps over just fine, but be aware the newer unit requires a new plug and has a different operating range than the stocker. Read about it in the OBDII TPI sticky. It will work, but operation will never be perfect
Thread Starter
On Probation
Joined: Mar 2010
Posts: 466
Likes: 0
Car: 1989 Formula,1991 z28
Engine: 400 Vortec Hsr,496bbc
Transmission: TKO600,TH400
Axle/Gears: 9"4.10, 9"3.73
Re: LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearanc
Plug the end of the rail to run the injectors in series. It will clear
The LTx IAC housing swaps over just fine, but be aware the newer unit requires a new plug and has a different operating range than the stocker. Read about it in the OBDII TPI sticky. It will work, but operation will never be perfect
The LTx IAC housing swaps over just fine, but be aware the newer unit requires a new plug and has a different operating range than the stocker. Read about it in the OBDII TPI sticky. It will work, but operation will never be perfect
i cant plug the rail, that -6 fitting is for the nitrous kit fuel feed
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Joined: Aug 1999
Posts: 1,053
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From: San Diego, CA
Car: 87 Buick GN
Engine: 3.8L (231 cid) V6
Transmission: 200-4R
Axle/Gears: 10 bolt G80/ 3.42
Re: LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearanc
heres some pics to show what my issue is...
before ya'll say flip the rails around and run them like holley suggest's..it aint gonna happen..i like how i have them routed, and fuel lines are already made and routed!
having looked at the IAC housing on the LT1 throttle bodys, it looks like the IAC motor is much shorter, and the connector faces FORWARD instead of pointing to the pass side.. looking at pictures, it looks like the LT1 iac, will bolt directly to a TPI tb..anybody tried this?
heres the issue im running into.
before ya'll say flip the rails around and run them like holley suggest's..it aint gonna happen..i like how i have them routed, and fuel lines are already made and routed!
having looked at the IAC housing on the LT1 throttle bodys, it looks like the IAC motor is much shorter, and the connector faces FORWARD instead of pointing to the pass side.. looking at pictures, it looks like the LT1 iac, will bolt directly to a TPI tb..anybody tried this?
heres the issue im running into.
I don't know if you solved this yet but I figured something like this would be your easiest and cheapest solution...http://www.casperselectronics.com/st...oducts_id=1009. It's for the IAC valve on the Grand National 3.8, but the same square 4 prong connector was used in many GM vehicles including the TPI F-bods.
Or if you've figured out a way to use an LT1 IAC housing, they make a plug and play harness for that...http://www.casperselectronics.com/st...oducts_id=1073
Hope that helps.
Thread Starter
On Probation
Joined: Mar 2010
Posts: 466
Likes: 0
Car: 1989 Formula,1991 z28
Engine: 400 Vortec Hsr,496bbc
Transmission: TKO600,TH400
Axle/Gears: 9"4.10, 9"3.73
Re: LT1 throttle body IAC housing, on TPI based throttle body, i HAVE to for clearanc
I don't know if you solved this yet but I figured something like this would be your easiest and cheapest solution...http://www.casperselectronics.com/st...oducts_id=1009. It's for the IAC valve on the Grand National 3.8, but the same square 4 prong connector was used in many GM vehicles including the TPI F-bods.
Or if you've figured out a way to use an LT1 IAC housing, they make a plug and play harness for that...http://www.casperselectronics.com/st...oducts_id=1073
Hope that helps.
Or if you've figured out a way to use an LT1 IAC housing, they make a plug and play harness for that...http://www.casperselectronics.com/st...oducts_id=1073
Hope that helps.
since i havent found an lt1 tb local, i might go with that extension harness, thanks man!
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