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-   -   how viable are the stock fd rims? (https://www.rx7club.com/race-car-tech-103/how-viable-stock-fd-rims-167857/)

particleeffect 03-18-03 09:00 PM

how viable are the stock fd rims?
 
I wasn't sure whether I should put this in here or wheels/tires.

For novice level things, open tracking, autox for fun, how do the stock fd rims stand up as platforms? Since I don't have anything against their style I don't want to change them any time soon for looks alone. Of course I probably couldn't fit 14" brakes in them, but do Apexi or JIC persay, coilovers fit without spacers?

Are tires somewhat less expensive than maybe the average 17's or 18's on an used on an FD?

I would think that the smaller size would help a little in autox.

rynberg 03-19-03 01:37 AM

Re: how viable are the stock fd rims?
 

Originally posted by particleeffect
For novice level things, open tracking, autox for fun, how do the stock fd rims stand up as platforms? Since I don't have anything against their style I don't want to change them any time soon for looks alone.
For a novice, even street tires on the stock rims will be all you can handle. As you get better, you can slap on some stickier tires (Toyo RA-1, Yoko A032R) for even better performance. The stock rims are lighter than almost any aftermarket wheel and are wide enough to support good sized tires. There's no need for you to upgrade.


Originally posted by particleeffect
Of course I probably couldn't fit 14" brakes in them, but do Apexi or JIC persay, coilovers fit without spacers?
You don't need 14" brakes for autocrossing or even road racing if you are a novice. I think you are confused about coil-overs. Most coil-overs are 2-1/2 diameter springs, the stock springs are 4-inch diameter. People switch to coil-overs to use wider wheels (and adjustable ride height and damping). The stock suspension is fine for a novice. Even an experienced racer like SleepR1 only uses H&R springs and the stock R1 shocks (with aftermarket sway bars). Coil-overs are a big investment in money and time and will probably hurt you as a novice.


Originally posted by particleeffect
Are tires somewhat less expensive than maybe the average 17's or 18's on an used on an FD?
Take a look at www.tirerack.com, you'll see that for the most part, 17" and 18" street tires are MUCH more expensive than 16" street tires. I think there are a lot less sizes available in 18" for racing tires (probably less of an issue now a days...) as well.

ttpowerd 03-19-03 09:23 AM

Very good information! I just purchased a second set of stock wheels for autox since I did not see the use in spending 2k on a set of wheels alone.

DamonB 03-19-03 10:51 AM

Stock 16x8 wheels are very light and strong. If you are running the stock size I see no reason to go to a different wheel unless you are going to spend a whole lot of $$$ and go with a forged racing wheel (only thing that's lighter). Even then IMO it isn't worth the investment.

Stockers are the best bang for the buck and if you want bling have them powdercoated. I have three sets of stockers and am going to have one set refinished in the near future; keep your eyes out for pics!

redrotorR1 03-19-03 02:59 PM

The stock wheels are good for running 245/45 16's; which is enough grip for most newbies. There's no point to upgrading brakes in auto-x unless you are just dying to compete in AP or SM2. And if you're new to auto-x, you definitely DON"T want to start competing from there. (Talk about a long uphill climb ....) Not to mention, the stock FD brakes are still kick-ass brakes in general.

I'll argue all day about the benefits of upgraded springs and shocks. But, that's another topic. FWIW, you won't need spacers with most of the shock/spring upgrades that are available. I don't know of any setups that don't work with the stock wheels.

Turbonut 03-19-03 03:45 PM

Just an FYI....The '93 (Hope it's only '93) stock wheels had a problem in design/manufacturing. Under extremely heavy loads the centers would blow away from the outer wheel during road racing events. Saw evidence of this in a few mags.
Hopefully the later models have been corrected...Don't know though.
Maybe others have more input.

TYSON 03-19-03 04:12 PM

Early in 93 problem only. Corrected midway through production run.

particleeffect 03-19-03 04:12 PM

Ahh, thanks for the input. I'm not considering massive brakes at all, just thinking outloud. Fancy coilovers enter my mind sometimes, but I guess I'll still with the R1 stuff for a while after I replace the old bushings.

rotarypower101 03-20-03 12:12 AM

Uhh.. as strange as it may sound I think it is the earlier models that had the wheels that are not prone to cracking. I was asking Turbojeff about that and it seems that the earlier models are the ones that are not having the problems!
I guess that’s one of the only benefit to having a early model fd’s, well.. that and the peeling interior pieces is always a bonus too I guess!!


"Well I am an engineer . He is right in a general sense, usually a sharper corner is going to lead to a stress concentration. Things are always that simple though, the "sharp" corner isn't at the base of the "beam", it is on the side of the "beam" (wheel spoke).

When designing a part like a wheel standard stress calculations don't work, you've got to do some FEA to see what is really happening.

So why would Mazda change in the later years to wheels that are more prone to crack? GOOD QUESTION! From all the research I've done it is true, Mazda did change to the weak style. My 93 R1 was built in 2/92, it had the non-cracking style wheels dated 1/92. I've looked at LOTS of wheels, build dates starting after the ~middle of 92 were the crack prone style.

To see pics of a cracked wheel check out the link that MaxCooper posted. The wheel I have cracked is in the same place.

Later,
Jeff"

neevosh 03-20-03 02:11 AM

The early FD wheels were prone to cracking. They can be identified by the PFD letters on the rim. They were a very brittle casting. Mazda fixed the problem which consequentially made them a bit heavier. Still very light for a 16x8 wheel.

SleepR1 03-20-03 05:09 AM

Re: Re: how viable are the stock fd rims?
 

Originally posted by rynberg
The stock suspension is fine for a novice. Even an experienced racer like SleepR1 only uses H&R springs and the stock R1 shocks (with aftermarket sway bars).
Setup works beautifully for a daily driven FD that's gets thrashed on the track. Hey I've got my first track event of 2003 this Saturday :) Woo hooo, can't wait :)

Seriously. I ran 16-inch wheels/tires for about 6 years of ownership. Took me that long to develop competent (not expert) driving skiills in the FD. 17s are ideal though, if and when you're ready for them :) See my sig for mods.

Best of luck!

finky 03-20-03 10:01 AM

I just bought another set of FD rims for my slicks. 16x8s have plenty of grip with 245/45/16s. They are inexpensive also if you look in the right place.

ArcWelder 03-21-03 12:26 PM

I did a search under wheel cracking and got MANY hits.

Try:
https://www.rx7club.com/forum/showth...heels+cracking

or

https://www.rx7club.com/forum/showth...hreadid=107744

In each of the links you'll see examples of the weaker and stronger wheels.

BTW, after several years of running on the track, I'm stiill using the stock(stronger) wheels and Toyo RA1's.

Mark


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