1990 L98 Plenum question
Thread Starter
4th Gear
Joined: May 2007
Posts: 4
Likes: 0
1990 L98 Plenum question
I need some help. My 1990 L98 has no MAF. I read in my Hayne's manual that in 1990 the MAF was eliminated, and the IAT sensor was used. Do previous years have IAT sensor? I read on a Camaro forum that engines with a MAF have an MAT sensor, and the name of the sensor changed to IAT when MAF was eliminated.
What I really want to know is this:
Can I install a 1989 plenum on my 1990? Will I be able to mount my IAT in the 1989 plenum? The runners look different, the 1989's look like individual tubes but mine are solid. Are the runners otherwise the same?
Thanks,
What I really want to know is this:
Can I install a 1989 plenum on my 1990? Will I be able to mount my IAT in the 1989 plenum? The runners look different, the 1989's look like individual tubes but mine are solid. Are the runners otherwise the same?
Thanks,
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
'91 vettes have the MAP sensor (Manifold Absolute Pressure) instead of the MAF. Your '90 should have the MAF between the air cleaner box and the throttle body. If you dont have one, then its possible that a previous owner may have modified yours.
Yes All TPI cars have the IAT sensor (Intake Air Temperature) and thats on the bottom side of the plenum. Yes, you can use TPI parts from an '89.
Yes All TPI cars have the IAT sensor (Intake Air Temperature) and thats on the bottom side of the plenum. Yes, you can use TPI parts from an '89.
Last edited by Demonic85; Jun 4, 2007 at 12:23 AM. Reason: a few changes
Team Owner
Joined: May 2002
Posts: 24,337
Likes: 25
From: San Diego , CA Double Yellow DirtBags 1985..Z51..6-speed
If your runners only have 2 big tubes per side, they are aftermarket high flow runners.
All TPIs have 4 runners per side. There were numerous changes to the plenums, runners and baseplate.
The IAT/MAT whatever you want to call it is not important. Also your Haynes manual is full of horse sh**.
Read here for interchangeability:
http://www.fuelinjection.com/portinj.html
All TPIs have 4 runners per side. There were numerous changes to the plenums, runners and baseplate.
The IAT/MAT whatever you want to call it is not important. Also your Haynes manual is full of horse sh**.
Read here for interchangeability:
http://www.fuelinjection.com/portinj.html
Team Owner
Joined: Feb 2006
Posts: 24,460
Likes: 7
From: sw Ohio
If your runners only have 2 big tubes per side, they are aftermarket high flow runners.
All TPIs have 4 runners per side. There were numerous changes to the plenums, runners and baseplate.
The IAT/MAT whatever you want to call it is not important. Also your Haynes manual is full of horse sh**.
Read here for interchangeability:
http://www.fuelinjection.com/portinj.html
All TPIs have 4 runners per side. There were numerous changes to the plenums, runners and baseplate.
The IAT/MAT whatever you want to call it is not important. Also your Haynes manual is full of horse sh**.
Read here for interchangeability:
http://www.fuelinjection.com/portinj.html
but I also have the Hayne's manual and it says that only '84 and '91-'94 have the MAP sensor.
Thread Starter
4th Gear
Joined: May 2007
Posts: 4
Likes: 0
Thanks!
That's a pretty informative read. I will finish it tomorrow at work.
I see now that I have SLP runners.
I usually only use the Hayne's manual as a last resort.
My L98 definitely has no MAF.
It looks like I can use the 1989 plenum with some minor modifications.
The one that I am looking at has been "siamesed" . Does anyone have any comments about using this with the SLP runners?
That's a pretty informative read. I will finish it tomorrow at work.
I see now that I have SLP runners.
I usually only use the Hayne's manual as a last resort.
My L98 definitely has no MAF.
It looks like I can use the 1989 plenum with some minor modifications.
The one that I am looking at has been "siamesed" . Does anyone have any comments about using this with the SLP runners?
Melting Slicks
Joined: Jan 2002
Posts: 2,238
Likes: 4
From: Milan
'91 vettes have the MAP sensor (Manifold Absolute Pressure) instead of the MAF. Your '90 should have the MAF between the air cleaner box and the throttle body. If you dont have one, then its possible that a previous owner may have modified yours.
Yes All TPI cars have the IAT sensor (Intake Air Temperature) and thats on the bottom side of the plenum. Yes, you can use TPI parts from an '89.
Yes All TPI cars have the IAT sensor (Intake Air Temperature) and thats on the bottom side of the plenum. Yes, you can use TPI parts from an '89.
the 90 is MAP equipped as a 91.NO MAF on a 90.
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Race Director
Joined: Jun 2004
Posts: 13,939
Likes: 705
From: WI
My '88 has the MAT in the bottem of the plenum. If you can't put it there, you can put it just about anywhere else. After I ported my plenum I didn't like how it stuck up in front of the back runner. So I relocated it to the front by the air filter. I reused some wire that I had so it was just a simple solder splice, didn't take long and it was free.
