Help Needed: 90 motor into 95 chassis

A Q45 forum / Cima forum for the President of Infiniti's lineup. Brought to you by Infiniti Parts USA, your OEM source for Q45 parts!
User avatar
AZhitman
Administrator
Posts: 54540
Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
Location: Surprise, Arizona
Contact:

Post

Can I get a basic rundown of the differences between the two, so that I can plan out part purchases?

Looks like there's more differences than we anticipated, including the ignition system and much of the emissions controls.


User avatar
elwesso
Posts: 30810
Joined: Sun Feb 23, 2003 4:52 pm
Car: 94 Infiniti Q45t 5 spd
2007 BMW M Coupe
2007 Infiniti G35 S 6MT
Location: Indiana
Contact:

Post

the easiest thing for you to do is get a complete 90-93 ECU harness!

maxnix
Posts: 22627
Joined: Mon Jul 22, 2002 8:11 pm
Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45

Post

I hate to say it, but just don't do it. Get a 94-95.

3Q Jay
Posts: 2560
Joined: Sat May 08, 2004 6:23 pm
Car: 94 Q45a
95 Q45a (sold)
97 Q45t (sold)
01 B15 Sentra (Daughter's)
Also Mine...
2010 A6 Avant
1977 F-150 (460!)
Location: Florida Coast

Post

all short blocks are the same. you already know the heads are different.the CAS is different. that one may be the biggest bugger.

you found a crate engine for a '90? if so, i could contact daedalus for you (another guy who's been away even longer than me). he has a 94 crate motor in his garage. AND a virgin short block. man i about wet myself.

anyway he is thinking of swapping the '94 crate motor into his '90, but faces the same issues.

no, you can't just swap CAS.


User avatar
AZhitman
Administrator
Posts: 54540
Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
Location: Surprise, Arizona
Contact:

Post

elwesso wrote:the easiest thing for you to do is get a complete 90-93 ECU harness!
Not a bad idea Wes...Wonder if PopPop has one available?

I could throw in one of Rob's good ECU's then too...

Q45tech
Moderator
Posts: 14296
Joined: Tue Apr 30, 2002 3:19 am
Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl

Post

Remember the 94 emisson max levels are lower. so in theory a 90-93 engine in a 94 Q is non compliant.............oval ports, injectors, and primary catalyst different.

You can swap a newer engine [of same size or lower] in the vehicle but going back is prohibited by Clean Air Act.

All about grams of polluntants per mile driven.

User avatar
AZhitman
Administrator
Posts: 54540
Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
Location: Surprise, Arizona
Contact:

Post

Any more advice?

I'll be fitting new cats, deleting the precats...

User avatar
AZhitman
Administrator
Posts: 54540
Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
Location: Surprise, Arizona
Contact:

Post

Anyone? Bueller?

User avatar
elwesso
Posts: 30810
Joined: Sun Feb 23, 2003 4:52 pm
Car: 94 Infiniti Q45t 5 spd
2007 BMW M Coupe
2007 Infiniti G35 S 6MT
Location: Indiana
Contact:

Post

get the new harness and youll be fine...!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

PopPop
Posts: 3129
Joined: Tue Dec 20, 2005 8:50 pm
Car: 1990-91 infiniti Q45's, S13 Coupe, 3rd GEN. Max

Post

AZhitman wrote:Anyone? Bueller?
I know Greg that 89-92 transmissions are the same! 93&94 are the same and 95 are one year only may have to switch it out and may not! Might have to swap out TCU because ECU still works with TCU as a unit for Optimum Performance! You will also have to switch to the 90-94 MAF!

User avatar
AZhitman
Administrator
Posts: 54540
Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
Location: Surprise, Arizona
Contact:

Post

Ty, you have a 90-93 engine harness?

Q45tech
Moderator
Posts: 14296
Joined: Tue Apr 30, 2002 3:19 am
Car: 1990 Q45 342,400 miles 22 years ownership with original engine
1995 G20t 5 speed 334,000 miles 16" 2002 wheels - 205/50/16 Sr20ve vvl

Post

Careful about harness swapping as AC aux fan is controlled by ecu.

maxnix
Posts: 22627
Joined: Mon Jul 22, 2002 8:11 pm
Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45

Post

Q45tech wrote:Careful about harness swapping as AC aux fan is controlled by ecu.
I just have to think it is a real step backwards to try to mate a pre 1994 engine harness to a later loom. Seems like it would have to be custom and thus expensive, or time consuming.

Whatever, good luck!

User avatar
elwesso
Posts: 30810
Joined: Sun Feb 23, 2003 4:52 pm
Car: 94 Infiniti Q45t 5 spd
2007 BMW M Coupe
2007 Infiniti G35 S 6MT
Location: Indiana
Contact:

Post

you dont have to switch to a 90-94 MAF, you cna just use the later MAF connector from your other harness...

The aux fan idont think woudl be an issue since it doesnt come on unless the engine is technically overheating, and i know greg uses AC most the time, thus itd be on for the AC anyway.

maxnix
Posts: 22627
Joined: Mon Jul 22, 2002 8:11 pm
Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45

Post

elwesso wrote:The aux fan idont think woudl be an issue since it doesnt come on unless the engine is technically overheating, and i know greg uses AC most the time, thus itd be on for the AC anyway.
Really? Not for me, but it is a two speed unit where the earlier is a single speed.

Trace enough of the loom differneces and cutomize the engine harness and all will work fine. Just seems like a false economy to me. But it's not my project.

User avatar
AZhitman
Administrator
Posts: 54540
Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
Location: Surprise, Arizona
Contact:

Post

OK - Well, we can work around the aux fan issue.

Hell, I may add two low-draw, high-CFM e-fans anyway. And an oil cooler.

Any other issues we might encounter?

maxnix
Posts: 22627
Joined: Mon Jul 22, 2002 8:11 pm
Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45

Post

AZhitman wrote:Hell, I may add two low-draw, high-CFM e-fans anyway.
The FY33 has this superior configuration.

User avatar
AZhitman
Administrator
Posts: 54540
Joined: Mon Apr 29, 2002 2:04 am
Car: 58 L210, 63 Bluebird RHD, 64 NL320, 65 SPL310, 66 411 RHD, 67 WRL411, 68 510 SR20, 75 280Z RB25, 77 620 SR20, 79 B310, 90 Z32, 91 GTi-R, 92 Silvia Qs, 98 S14, 23 Z.
Location: Surprise, Arizona
Contact:

Post

Good. Done deal.

Where's that Dennis guy when I need him...

maxnix
Posts: 22627
Joined: Mon Jul 22, 2002 8:11 pm
Car: 1995 Infiniti Q45
1995 Infiniti Q45t
2000 Infiniti Q45

Post

AZhitman wrote:Good. Done deal.

Where's that Dennis guy when I need him...
Lest I create confusion, these fans are primarily for the condenser. It still retains the viscous clutch engine driven fan for the radiator.


Return to “Q45 Forum / Cima Forum”