'94 Q45t handling tips?
'94 Q45t handling tips?
Thanks to all for the great info so far. I've done a couple searches, but haven't found the right answer yet. Car is a stock '94 Q45t with 90k on it. Other than some frustrating fuel pump/relay related problems that were finally resolved, it's been a great car. Basically the the car has had dealer service up to 80k, and then regular fluid changes after that. It's the wife's car, so I rarely drive it. However, I think it's time for new shocks. What's the normal or preferred replacements, estimated price, and best place to purchase them? I have access to a lift and most auto tools, and possess a fair amount of mechanical skill. But frankly I'm used to working on old American muscle cars, and don't mind farming this out if it's a pain in the rear. Rather not replace tires/wheels yet. Not looking for stiff Formula One handling, but better than stock would be nice. Any recommendations? Thanks TP
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AZhitman
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- 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
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TP:
Here's my prescription for making a 94-96 Q handle spectacularly, pick and choose from what you'd like.
New shocks: Go with the Tokico blues on all four corners, as everyone I know who has done this has been pleased with their performance. I don't think they're too stiff... They're real nice, and they're cheaper (approx $260 shipped).
Wheels/Tires: Seems the best compromise between weight, durability, price and strength is a set of takeoffs from a 97-01 Q. Go with the 16's with some quality, sticky, Z-rated 245/50/16's or find some 17's and go 245/45/17. Both fit well and retain the factory diameter, and will make TONS of difference in your car. I personally have 255/50ZR16's on a set of chromed 99's.
RSB: If you can find a 20mm rear sway bar from a 09-96 ACTIVE Q45, grab it. Stiffens up the roll in the rear, reduces the "wallowing" over uneven pavement.
Springs: I have the Eibach springs on my Q. Yours are likely shot by now, and the Eibachs were much cheaper ($230) than replacements from Infiniti. Minimal increase in stiffness, feels MUCH nicer and reduces body roll. Some would say the handling improvement is negligible, but along with the other mods listed, it's impressive. Looks fantastic too.
New tension rod bushings: If they haven't been replaced (at least) once, they're shot. Silicone-filled bushings often crack and leak, rendering the front suspension sloppy. Get them from Joe at Infiniti of Scottsdale and have them pressed in locally.
New upper links: See above.
FSTB: A couple of us (myself and Jeff Williams) have successfully modified a front strut tower brace from a 200+ Maxima to fit the Q. Makes a WORLD of difference in steering responsiveness and turn-in. Best bang for the buck, at approximately $10 plus shipping off eBay.
New front sway bar bushings: Self-explanatory.
Alignment: Also self-explanatory.
Hope this helps....
Here's my prescription for making a 94-96 Q handle spectacularly, pick and choose from what you'd like.
New shocks: Go with the Tokico blues on all four corners, as everyone I know who has done this has been pleased with their performance. I don't think they're too stiff... They're real nice, and they're cheaper (approx $260 shipped).
Wheels/Tires: Seems the best compromise between weight, durability, price and strength is a set of takeoffs from a 97-01 Q. Go with the 16's with some quality, sticky, Z-rated 245/50/16's or find some 17's and go 245/45/17. Both fit well and retain the factory diameter, and will make TONS of difference in your car. I personally have 255/50ZR16's on a set of chromed 99's.
RSB: If you can find a 20mm rear sway bar from a 09-96 ACTIVE Q45, grab it. Stiffens up the roll in the rear, reduces the "wallowing" over uneven pavement.
Springs: I have the Eibach springs on my Q. Yours are likely shot by now, and the Eibachs were much cheaper ($230) than replacements from Infiniti. Minimal increase in stiffness, feels MUCH nicer and reduces body roll. Some would say the handling improvement is negligible, but along with the other mods listed, it's impressive. Looks fantastic too.
New tension rod bushings: If they haven't been replaced (at least) once, they're shot. Silicone-filled bushings often crack and leak, rendering the front suspension sloppy. Get them from Joe at Infiniti of Scottsdale and have them pressed in locally.
New upper links: See above.
FSTB: A couple of us (myself and Jeff Williams) have successfully modified a front strut tower brace from a 200+ Maxima to fit the Q. Makes a WORLD of difference in steering responsiveness and turn-in. Best bang for the buck, at approximately $10 plus shipping off eBay.
New front sway bar bushings: Self-explanatory.
Alignment: Also self-explanatory.
Hope this helps....
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AZhitman
- Administrator
- Posts: 54542
- 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:
BTW - Shocks are a DIY without too much knowledge. Remove shock/spring assembly as a unit (search) and take to a local shop to have the springs compressed and swapped onto the new shocks. Shouldn't cost more than $20-30 for all four. I did mine in under 2 hours, including waiting on the shop to swap springs.
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Q45tech
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- 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
Suspension mods are great but they can only do so much! They can however affect the feel of the car [positively] where you can safely explore the limits of what ever tire you decide upon.
The Q were way UNDER TIRED vs what is possible considering the weight on the front.The 1521 pound max load index [of oem 95V] limits what is possible even in the finest tire, as the slip angles are a function of real load vs max load [which is exceeded easily as most don't run enough air pressure].
Something in a 55>50>45 aspect ratio with a higher than oem load index say a 98 or 100 will better the handling [the actual increase in G in a slalom/skid pad] more than any suspension modification.IF the tread compound is soft [very fast wearing] and allows the higher friction to develop!
But there are theorectical maximums based on the front and total weight as it is impossible to fit tires on the front beyond 255/50/16 -------a 98 load rating.
Many of the heavier MB and BMW use 101-103 rated reinforced tires.......in narrower sizes. Really depends on what manuevers you want to enhance.
The Q were way UNDER TIRED vs what is possible considering the weight on the front.The 1521 pound max load index [of oem 95V] limits what is possible even in the finest tire, as the slip angles are a function of real load vs max load [which is exceeded easily as most don't run enough air pressure].
Something in a 55>50>45 aspect ratio with a higher than oem load index say a 98 or 100 will better the handling [the actual increase in G in a slalom/skid pad] more than any suspension modification.IF the tread compound is soft [very fast wearing] and allows the higher friction to develop!
But there are theorectical maximums based on the front and total weight as it is impossible to fit tires on the front beyond 255/50/16 -------a 98 load rating.
Many of the heavier MB and BMW use 101-103 rated reinforced tires.......in narrower sizes. Really depends on what manuevers you want to enhance.
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AZhitman
- Administrator
- Posts: 54542
- 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:
Q45tech wrote:But there are theorectical maximums based on the front and total weight as it is impossible to fit tires on the front beyond 255/50/16 -------a 98 load rating.
One timy correction: My 255's are a 99 load rating.
Otherwise, Dennis is right on - Tires are the #1 enhancement you can make. Don't skimp here, as anything else you do relies on the tires....
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elwesso
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- Car: 94 Infiniti Q45t 5 spd
2007 BMW M Coupe
2007 Infiniti G35 S 6MT - Location: Indiana
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Yes...... Tires are KEY!!!! I learned the hard way...... man I wish I had Z rated tires.... Oh well, I guess im limited to 130 right now 
Get all the suspension rubber and tockicos and go from there..... The difference is night and day...... My next mod would be the FSTB and rear sway bar....... Now, to find an active Q.......
BTW, how hard is it to put a rear sway bar on from an active Q onto a regular Q.?
Get all the suspension rubber and tockicos and go from there..... The difference is night and day...... My next mod would be the FSTB and rear sway bar....... Now, to find an active Q.......
BTW, how hard is it to put a rear sway bar on from an active Q onto a regular Q.?
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Q45tech
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- 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
H rated tires are tested when brand new not used!
They are tested on a lab machine in 70F ambient going straight [not turning] plus the industry standard is ZERO CAMBER & ZERO CASTER! The Q rolling down the highway at speed places loads that the tire was never designed to see for more than a few seconds in braking.
The 255/50/16 was the size for the old Corvette [used on little else].
Don't think for a moment that a USED 1-2 year old H rated tire is safe to drive 130 mph on for any time period..[on the highway].......many tires are old sitting in warehouses, then older at tire dealers,...........oxygen/ozone exposure and temperature cycling in transport/storage before they ever get on your car.
Think of a USED 2 year old H rated as a very safe 80, 85 even 90 MPH tire on a Q45, nothing more.
H rated tires for use on policecars [225/60/16] are very special H rated tires! Quite different from the H rated sold to public. They have DUAL reinforced sidewalls and Nylon belts and safety caps.More V/Z like in their construction and are rated for a heavy car with camber and caster applied in the testing!
They are tested on a lab machine in 70F ambient going straight [not turning] plus the industry standard is ZERO CAMBER & ZERO CASTER! The Q rolling down the highway at speed places loads that the tire was never designed to see for more than a few seconds in braking.
The 255/50/16 was the size for the old Corvette [used on little else].
Don't think for a moment that a USED 1-2 year old H rated tire is safe to drive 130 mph on for any time period..[on the highway].......many tires are old sitting in warehouses, then older at tire dealers,...........oxygen/ozone exposure and temperature cycling in transport/storage before they ever get on your car.
Think of a USED 2 year old H rated as a very safe 80, 85 even 90 MPH tire on a Q45, nothing more.
H rated tires for use on policecars [225/60/16] are very special H rated tires! Quite different from the H rated sold to public. They have DUAL reinforced sidewalls and Nylon belts and safety caps.More V/Z like in their construction and are rated for a heavy car with camber and caster applied in the testing!
The Michelin Pilot XGT H4 in 255/50-16 comes in two variants. The made in USA tire has one ply sidewalls. The made in Canada has twp ply sidewalls-like the XGT V. Priced accordingly. I have the US models, but am thinking about getting the Canadians as a replacement.
Anyone know about the rubber compounds? I think both are 400 treadwear.
Anyone know about the rubber compounds? I think both are 400 treadwear.
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Q45tech
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- 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
On a Q even in the H4 235/60/15 size take the 400 treadwear with a grain of salt based on 3 sets and very frequent rotation including at least one rim flip...........think 30-33k MAX.
Half worn at 15k but the under compound hardens from exposure at least in Southern temperatures. Smart to change/replace these when its cooler because they will be decent in the first winter.
The single ply is like a 1.5 ply in the strength [thickness] of the polyester used.Never seen [H4] a sidewall blow out with less than 25k on a Q. We have almost 100 customers who use them in 3 sizes.
Half worn at 15k but the under compound hardens from exposure at least in Southern temperatures. Smart to change/replace these when its cooler because they will be decent in the first winter.
The single ply is like a 1.5 ply in the strength [thickness] of the polyester used.Never seen [H4] a sidewall blow out with less than 25k on a Q. We have almost 100 customers who use them in 3 sizes.