Question on 1990 5.0 IROC TPI swap

Cuse99

Apprentice
Dec 21, 2020
99
18
I got a line on a '90 5.0 TPI from an IROC. Comes with the 700R4 trans. Looks likes its mostly all there from the photos. It has the wiring harness but I can see there is an empty brake on the both sides. Probably a pump of some kind. Claims to have 48K miles on it. For my plans on my Elco this might be just the ticket. But I'm curious of what to look out for and gotchas on a swap for this.

Disregarding the trans for the moment because I know I'll need a new cross member and driveshaft etc...
  • What do I need to look out for in the motor?
  • Are there parts that are really expensive or hard to find that I should make sure are included? Like the CPU?
  • Will this unit otherwise drop it?
  • How about the wiring?
If this isn't too complex I'll pursue it. I remember these motors made really good low end torque and decent power. More than enough for a street car daily driver.

I appreciate the comments in advance, thank you.
 
Last edited:

ck80

Royal Smart Person
Feb 18, 2014
1,695
113
I got a line on a '90 5.0 TPI from an IROC. Comes with the 700R4 trans. Looks likes its mostly all there from the photos. It has the wiring harness but I can see there is an empty brake on the both sides. Probably a pump of some kind. Claims to have 48K miles on it. For my plans on my Elco this might be just the ticket. But I'm curious of what to look out for and gotchas on a swap for this.

Disregarding the trans for the moment because I know I'll need a new cross member and driveshaft etc...
  • What do I need to look out for in the motor?
  • Are there parts that are really expensive or hard to find that I should make sure are included? Like the CPU?
  • Will this unit otherwise drop it?
  • How about the wiring?
If this isn't too complex I'll pursue it. I remember these motors made really good low end torque and decent power. More than enough for a street car daily driver.

I appreciate the comments in advance, thank you.
TPI setups are a minor pain to swap and arent easily nodded for further horsepower.

From a cost effective basis I'd hold out for a truck motor.
 

Cuse99

Apprentice
Thread starter
Dec 21, 2020
99
18
TPI setups are a minor pain to swap and arent easily nodded for further horsepower.

From a cost effective basis I'd hold out for a truck motor.
I'm not looking for more power, 275 HP is fine for me. What is cost effective about a truck motor? I'm not following?
 

motorheadmike

Geezer
Nov 18, 2009
6,344
113
Ottawa, Ontario Canada
  • Like
Reactions: 64nailhead

64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
2,236
113
Upstate NY
TPI is as easy as any other motor of that era. If you can afford it, then go with an aftermarket ECU, you need a fuel pump and lines. You'll need to modify the rear crossmember for the 700.
 

ck80

Royal Smart Person
Feb 18, 2014
1,695
113
I'm not looking for more power, 275 HP is fine for me. What is cost effective about a truck motor? I'm not following?
Search L31 or LO5 350 v8 truck builds.

They have roller lifters so no zddp or wiped cam worries, but can run off the original technology in your car.

You don't need to mess around with wiring conversions - they don't need a computer, but, if you REALLY wanted to you could use the stock one and setup.

No need to worry about out of production MAF and other sensors that drive you into cheapo Chinese or junk remanufactured as they fail.

Because they aren't fuel injected, you don't need a new gas tank, new sending unit, new larger diameter fuel lines, or to buy and wire in an electronic fuel pump.

A used motor will only cost you around 300-500 bucks complete top to bottom front to back with around 100k or less on it, leave lots of money to buy cam, heads, intake, and carb to really wake it up to the around 400hp range.
 

64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
2,236
113
Upstate NY
Dude, that’s a lot of hatin’ on the fuel injection.

Did your ex-wife used to prefer it or what?

Kidding of course. OP - I wouldn’t try it with a stock pcm. And beware that you’ll have $1500 in getting a TPI to go. I can break down the cost if you want. CK80 is correct that a carb setup L31 or L05 will be cheaper (but it won’t be anywhere as 😎)
 

64nailhead

Goat Herder
Supporting Member
Dec 1, 2014
2,236
113
Upstate NY
Nothin’ cooler than a TPI - not the fastest, but definitely cool (to me anyway)
 

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Clone TIE Pilot

Royal Smart Person
Aug 14, 2011
2,498
113
Galaxy far far away
Both TPI and L31 will likely require a electric fuel pump conversion. In tank pumps are generally the best. TPI was a popular old swap for G bodies years ago.
 

Texas82GP

Just-a-worm
Supporting Member
Apr 3, 2015
6,311
113
Spring, Texas
Search L31 or LO5 350 v8 truck builds.

They have roller lifters so no zddp or wiped cam worries, but can run off the original technology in your car.

You don't need to mess around with wiring conversions - they don't need a computer, but, if you REALLY wanted to you could use the stock one and setup.

No need to worry about out of production MAF and other sensors that drive you into cheapo Chinese or junk remanufactured as they fail.

Because they aren't fuel injected, you don't need a new gas tank, new sending unit, new larger diameter fuel lines, or to buy and wire in an electronic fuel pump.

A used motor will only cost you around 300-500 bucks complete top to bottom front to back with around 100k or less on it, leave lots of money to buy cam, heads, intake, and carb to really wake it up to the around 400hp range.
With all due respect, where are these 20+ year old, less than 100k mile truck engines, for cheap?
 
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