91 t-body and CAS in a 90

[turbo90gsx]

I no longer want the hassle of the IAC/FAIV, and would rather them be completely off the throttle body then just to pull the plugs and coolant lines from them. Is there anything else I would have to change in order to use a 91-throttle body? My 90 CAS is leaking oil where the wires come out at...pretty bad, which makes me think that it's probably not going to last much longer. I’m also wondering what much be changed in order to use the 91 CAS? I have easy access to these, that’s why I'm considering it.

 

[1stGenRocks]

for the cas theres a oring where it goes into the head. you might just need to change it.

the tb should be a bolt on swap if you blocking off the isc and fiav anyway. thats all thats different on them.

 

[turbo90gsx]

Well, I tried installing the 91 throttle body today, but was rather dissapointed becuse the TPS is now hitting the fuel rail. Does the 90 have a different fuel rail then the 91-94's, or is somthing eles just not right?

 

[turbo90gsx]

1G-specific conversion
This site is not letting me post on the thread on 90-91cas and throttle body, so maybe you can repost the info for me.
I have done the swap on my 90. the fuel rails are different, the clocking of the inlet flange is changed to accomadate the tps sensor on the 91 throttle body. What you need to do for the 91 CAS swap is cut the harness from the 90( when the wires get oily and heated they will become brittle and break. i know) and use it to plug into the 90 main harness. then take a plug for the 91 CAS harness to make an adapter harness. the wiring goes as such,
91 harness-----------90harness
large black-----------black
large red-------------red
small black-----------yellow
white-----------------white

the tps conversion is wire for wire color.

 

[azkikr10]

anyone get the throttlebody on without swapping fuel rails?

 

[TSIfreek]

I have a 91-93 TB and want to replace it on my 90. So I need to change the fuel rail and the TPS plug correct or do I need the 90-94 CAS as well???
Also does anyone have the codes/colors for switching the TPS plug/wires??? Or are they the same???

 

[turbo90gsx]

The only thing you need with the swap (other than the tps plug) is a 91-94 fuel rail. You also might want to thing about getting a little bit smaller bolts for the throttle body, because the 91-94's are a little bit skinnier. If you have accesses to a 91-94 CAS and plug I could suggest swapping that too, as the 90's have serious problems leaking oil and having the wires break off coming out of the CAS itself.

 

[wolf20043]

91 harness-----------90harness
large black-----------black
large red-------------red
small black-----------yellow
white-----------------white

the tps conversion is wire for wire color.

Since the thread is only less than 2 weeks I will ask here instead of starting a new one. Does that wiring apply to a '90 CAS in a '92 as well. Or am I going to need the '92 CAS?
Mike
And as far as the fuel rail, It has to be changed, as the plate that the fuel line bolts to is angle towards the TPS, which is bigger on the later 1g's, and gets in the way of the rail.

 

[turbo90gsx]

As long as the wires on the CAS are in the same order that is listed you'll be fine. Seems kindof weird to be putting a 90 in a 92 when the 92 have a better design. If I were you I'd keep looking for a 92 CAS.

 

[wolf20043]

After 4 days of waiting I decided to get the '92 anyway. More for reference than anything, never know when it could come in handy.

Mike

 

[nightspeed87]

I know this thread is old but Im just goint to post on this and someone pick back up on it...

I am putting a 90s 6bolt in my 93... I have full 90s tranny and everything that came with the motor.... I sold my 93 to the guy whos swapping the engine in for me, and I already kept my 93 cas ( since im keeping my 93 wiring harness... ) Now i take it that the 90s fuel rail/ tps/ and tb are different right?

So tell me what I will still need to do in using the 90s engine/ and head with the 93 wiring harness supposing i am using my 93 cass...

( I take it I will need the 91-93 fuel rail/ tb/ and tps.... I dont know about the isc or coolant flow lines... I have heard of ppl doing away with those two, what is the pros and cons of doing this? )

 

[turbo90gsx]

"( I take it I will need the 91-93 fuel rail/ tb/ and tps)" If you already have a 93 harness, then these are direct bolt on for you, no wire changing or anything. As far as IAC and the FAIV I have neither. I would sugjest that you keep your IAC, but eliminating the FAIV just lets your car idle at normal rpms no matter what temp the coolant is. Just run the water line that comes from the water pipe right back to the termostate housing. However you will also need to block off that passage way in the t-body or eles you will have an outragous idle.

 

[nightspeed87]

"( I take it I will need the 91-93 fuel rail/ tb/ and tps)" If you already have a 93 harness, then these are direct bolt on for you, no wire changing or anything. As far as IAC and the FAIV I have neither. I would sugjest that you keep your IAC, but eliminating the FAIV just lets your car idle at normal rpms no matter what temp the coolant is. Just run the water line that comes from the water pipe right back to the termostate housing. However you will also need to block off that passage way in the t-body or eles you will have an outragous idle.

Well I live in fl and it doesnt get any colder than 40 degrees and isnt the FAIV for warming it up??? If so I technically wont need it right?

Also will a 92 n/t fuel rail fit on the 90s engine and be the same size as the gsts fuel rail?
Or do n/ts have smaller rails? Therefore that will only leave me needing the throttle body and ISC from a turboed 4g63 91-94 yr engine right?

( Reason Im asking is because I have access to a lot of 2.0 n/t stuff at the junkyard... )

 

[turbo90gsx]

Yes, a 2.0n/t fuel rail is the same is a 2.0 turbo fuel rail.

 

[MILITISINVICTUS]

(to help me find this quickly on another computer)