MODDING/Maintenance Questions For a 1993 Q45

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illtww
Posts: 77
Joined: Mon Apr 28, 2003 4:50 pm

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HEY!!

I have some knowledge in modding. ( I own a 1990 AWD TSi and a 1993 Daytona IROC..)

But this Q45 has to be a little different. Not may jap v8’s you see everyday in America, so I am asking the experts..

This is my friend’s car and I rode in it and I almost crapped my pants. :) I WAS SOOO SUPPRISED at the power it had... Now to the point..

PLEASE REMEMBER THAT I AM ON A COLLEGE STUDENT BUDGET!!

Maintenance Questions......

1.It has 150k on it and I think it is about time for a FULL tranny flush. What kind of fluid do you recommend I flush it with? The machine at work uses DEXRON III but I doubt that is what it takes. Any upgraded fluids you recommend?

2.I know the power steering pump is whining... I saw on the forums that you recommended to use a turkey baster and flush it with ATF 3+? Like 6 Times or until pink?

3.Any other items to check at the high of a mileage? O2 sensors? Belts?

Now to the fun stuff...

MODS...

1.How free flowing is the STOCK exhaust system on this car? I was thinking of going 3" all the way back to a straight through muffler to reduce back pressure.. Can i loose the cat or is there an o2 sensor in it?

2.Air intake upgrade. I want to go CAI (pipe and filter...) any suggestions on pre-fabbed CAI's for this car?

4.JWT ecu. Do I need a TCU/ECU upgrade? How much for both and how much for the HP gains?

3.Shocks...Should I go wits Tokiko's? or maybe some KYB adjustables?


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AZhitman
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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 S13, 92 SE-R, 92 Silvia Qs, 98 S14.
Location: Surprise, Arizona
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1) Mobil 12) Correct3) Yes, and other things as well - Search...

1) Must keep cat. Even open headers only nets a few HP. No reason to modify.2) Not much gain here either. Stock is pretty impressive, believe it or not.3) ECU is smart - Best bang for the $. No need for TCU as you have 1st gear start. 4) Tokicos are the preferred route. I can get you all 4 for $260. Email me.

Other mods: 4.08 rear end (direct swap, I have one for sale).Upgraded tires and good maintenance go a LONG way.

Enjoy your stay - Spend a few hours perusing the Infiniti Online Mechanic section. Lots of wisdom there.

Welcome to NICO!

illtww
Posts: 77
Joined: Mon Apr 28, 2003 4:50 pm

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The tranny fluid.....

Mobile 1 ATf 3+? I don't have the manual in front of me... Also Tranny cooler a good idea?

Air Intake..I would like to replace it becaus the STOCK filter is done and it is NOT CHEAP. ANy suggestions on a CAI kit?

ECU..Cheapest place to sang one of these?

THanks,I hope to have lots of FUN!!

Travis

:ylsuper

Q45tech
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Posts: 14365
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

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Modifying the air filter system is one of the worst things you can do to a Q because of the potential for hot air ingestion!

The factory system was designed for a no more than 1/2% torque loss at 4,000 rpm. [1% at 6300 rpm]....the air horn actually provides a minute boost above 90 mph.

The engine is very very sensitive to hot air [especially found during idling and low speed operation] --- the exhaust from vehicles in front of you and heated roads creates power losses.

Even more critical is coolant temperature ..........it should never get above 194.9999F for max power........most older cars have marginal radiators [bugs/dirt/bent fins] [internal film] limiting heat transfer. Worn out foam surrounds [air bypass leaks].

Wasteful to do mods except JWT ecu [$595].

illtww
Posts: 77
Joined: Mon Apr 28, 2003 4:50 pm

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1.Is there an Aire system Upgrade that doesn't hurt perfromcance? IF so where can i get one/ look for one.

2.IS there a way to modify the exhaust so i can get a little more of a growl from the car without hurting perfromance?

3.What kind of plugs/plugs iwre yous guys suggest?NGK? Densos?

Thanks,Travis W.

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PalmerWMD
Posts: 18383
Joined: Mon Apr 29, 2002 3:14 pm
Car: 2004 350Z

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illtww wrote:1.Is there an Aire system Upgrade that doesn't hurt perfromcance? IF so where can i get one/ look for one.

2.IS there a way to modify the exhaust so i can get a little more of a growl from the car without hurting perfromance?

3.What kind of plugs/plugs iwre yous guys suggest?NGK? Densos?


Welcome to our club!!:cool:

Greg and Dennis have sage advice.In summary a combination of JWT ECU and 4.11 rear end will make you even quicker(w/o hurting top end belive it or not):

1) No.2) Yes, BRM and Borla both have exhausts for our cars which add growl (and some claim a very very small amount of power)3) Must use NGK's, no other plugs are know that work well with these cars.

Also please do a search for "guides" in our infinti article section (link is on homepage) before you sepnd $$ on anything.

Fred..:)

illtww
Posts: 77
Joined: Mon Apr 28, 2003 4:50 pm

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1.Where is the Best place to look for the exhaust upgrades on the web? Would 3" crush bent all the way back to a borla muffler really hurt this engine?

2.I guess i am gathering all i need for the ECU is a JWT ECU. DO I need a JWT TCU also?

3.I see you had an old Q that ran low 14's... What was you formula?

4.Is thre a cheaper air filter replacment? You can clean the K&N type that is why i am leaning heaily twards it. (anyone make a COLD AIR BOX for this car to eliminate hot air ingestion?

THanks,This place rocks. Reminds me of tampabaydsm!!!

illtww
Posts: 77
Joined: Mon Apr 28, 2003 4:50 pm

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One of my good freinds works up at Firestone (over 25 years exp...)

They also offer Carbon build up cleaner.

The put the chemical directly into the intake (TB) and it cleans out the Carbon build up on the top of the pistions etc but in the process it fouls out the plugs (need new ones anyways..)

I think i am gonna haev em do that also.

Thanks,Travis W.

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AZhitman
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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 S13, 92 SE-R, 92 Silvia Qs, 98 S14.
Location: Surprise, Arizona
Contact:

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Fred's right on the money.

Replace your airfilter with a Nissan unit - Not that expensive, call Joe at Scottsdale Infiniti parts and get the NICO discount.

CAI for the Q has been tried and the results were disappointing. The Q doesn't respond well to "rice" modifications. Some guys have the K&N drop-in and are happy with it, but it's easy to dirty up the MAF sensor, and AGAIN, you're not gaining HP. Plus, if you can't afford $7 for a new air filter element every 6K miles, you should sell the Q anyway.

For less $$$, try the Dynomax Ultraflow dual in/dual out muffler - You can get it installed for around $200, and it's got a nice growl, but don't expect major performance gains.

Maintenance will pay off more performance-wise. Have you cleaned the TB and plenum? Fuel rail flush? All synthetic fluids? Injector cleaning? New O2 sensors? New NGK plugs? New thermostat? Checked all injectors for full function?

An early 90's Q with the JWT ECU and good maintenance will run low 15's to high 14's all day long.

Also, find out if the guides have been replaced. If not, you're driving around in a grenade with the pin pulled.

There was a member who paid $1300 for a custom, fully mandrel bent stainless 2.5" dual exhaust system with Borlas and free-flow cats. Gained MINIMAL HP, and has since removed the system and sold it.

You need to realize the Q was designed to operate on the ragged edge of performance vs driveability. There's just not a wealth of "hidden HP" that the little Japanese engineers "neglected" to tap into. You get their very best every time you mash the throttle.

Like I said before, spend a day or 3 reading the Online Mechanic - You'll know all you need to know by then. :D

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PalmerWMD
Posts: 18383
Joined: Mon Apr 29, 2002 3:14 pm
Car: 2004 350Z

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illtww wrote:1.Where is the Best place to look for the exhaust upgrades on the web? Would 3" crush bent all the way back to a borla muffler really hurt this engine?

2.I guess i am gathering all i need for the ECU is a JWT ECU. DO I need a JWT TCU also?

3.I see you had an old Q that ran low 14's... What was you formula?

4.Is thre a cheaper air filter replacment? You can clean the K&N type that is why i am leaning heaily twards it. (anyone make a COLD AIR BOX for this car to eliminate hot air ingestion?

THanks,This place rocks. Reminds me of tampabaydsm!!!


1)BRM is one of our sponsors making it possbile for us to be here, help us out and give them a call and say you are from NICO.Their banner rotates thru our top display.2) You dont need the TCU as you have a 93 (typically the 92 and earlier drivers want the TCU as their TCU's are less aggressive than yours ie second gear start)3) Read this link:http://www.nissaninfiniticlub....shtmlIt includes some performance articles as well as a complete and detailed description of this car under (BAD Q45), where Dr Birkmeier , this sites founder, desribes the Q 45 mods in detail and their effects.

4) There are 2 schools of thought on this issue on these boards #1: No oil based filters as the miniscule gains are nullified by by hot air ingestion and potential MAF problems due to oil .School#2 (the minority) says K&N and such are ok to use ifa cold air intake in made of them. There are installation instructions on this, floating around on theses boards.

Finally when u scroll thru the infiniti articles section I linked above, read the article "90-93 guides"

Fred..:)

illtww
Posts: 77
Joined: Mon Apr 28, 2003 4:50 pm

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hmm..

the link just brings me to a blank search page.. DId you search for "guides" i did and i got a lot of timing guide hits etc..

Can the cat be deleted easily on these cars? No o2 worries etc...

Thanks,Travis W.

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PalmerWMD
Posts: 18383
Joined: Mon Apr 29, 2002 3:14 pm
Car: 2004 350Z

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illtww wrote:hmm..

the link just brings me to a blank search page.. DId you search for "guides" i did and i got a lot of timing guide hits etc..Can the cat be deleted easily on these cars? No o2 worries etc...Travis W.


I edited the link it now works.

Fred..:)

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AZhitman
Administrator
Posts: 71063
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 S13, 92 SE-R, 92 Silvia Qs, 98 S14.
Location: Surprise, Arizona
Contact:

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Travis - PLEASE read the above. We're trying to help you out brotha - The answers are all here. Read those timing guide threads, that's critical.

Can't eliminate cats - It's illegal, and they don't really offer that much restriction.

Fred, can you fix that link?

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PalmerWMD
Posts: 18383
Joined: Mon Apr 29, 2002 3:14 pm
Car: 2004 350Z

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Also keep in mind most of our articles are compilations of threads we had in our old UBB boards.

We picked the more informative threads to save and many of them became our articles.

Fred...:)

illtww
Posts: 77
Joined: Mon Apr 28, 2003 4:50 pm

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I saw those links lsat night. They were kinda like discussing back and forth the benefits/non-benefits.

Hey fred I migt give you a call later on if that is cool.

Thanks,You guys ROCK!!

:ylsuper

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PalmerWMD
Posts: 18383
Joined: Mon Apr 29, 2002 3:14 pm
Car: 2004 350Z

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No prob give me a call after 4pm EST as I am at work now.Be sure to read those articles, dont miss the "more" button on the bottom right either.

Fred..:)

PS: Thanks for the kind words:D

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Eswift
Posts: 1194
Joined: Mon Jul 29, 2002 4:48 pm
Car: should be obvious enough

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Q45tech wrote:the air horn actually provides a minute boost above 90 mph.


i simply dont believe that the increasing viscous forces and speed-proportional minor losses in the intake tract and plenum dont dissipate this minor upstream pressure increase. even if it does manage to produce a minute amount of boost at the runners, it is doubtfully noticeable.

what would be noticeable at 90mph would be the significant change in avg intake charge temperature, and thus air density..etc


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