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Any member cut their FD3s frame rail inorder to get proper suspension stroke

Old 01-24-17, 01:19 AM
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Any member cut their FD3s frame rail inorder to get proper suspension stroke

One of weakness of lowering the FD is u will hit the frame rail!!! That why I think in most of case is to use 17inch slick some thing under 250
But lately is hard to find proper size
And in my case with 300/650/18 slick althought with 30kg spring I still hit frame rail time to time on hard braking !!!
So during this Offseason I decide to chop the frame rail and reweld to top !!
By doing this I gain another 1.5cm of clearance, hope this will slove my problem
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Old 01-25-17, 11:15 AM
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I think you should have gone to stiffer springs . Most guys with those tires run 1100 -1300 lb springs. Your car will still dive now, just more!
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Old 01-25-17, 02:30 PM
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With my rough and ready calc of divide by 2, he's more than 1500 lb already. Ride height and shock valving might have been my first port of call. Any bumpsteer correction on that thing?

Can't get over how popular it was with the Japanese to waste their time pop riveting - with what looks like aluminium rivets, rather than stitch welding back then.
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Old 01-25-17, 02:41 PM
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The Japanese GT300 cars had to run this too tall for FD RX-7 tire size as well.

This is Revolution FD, but I believe is an ex-GT300 race car.
http://image.superstreetonline.com/f...ect-mu-caliper

You can see once they are back on correct diameter tires the modifications to unibody and body contour are not needed.
http://image.superstreetonline.com/f...ce-rear-bumper
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Old 01-31-17, 09:21 PM
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Originally Posted by racingdriver
I think you should have gone to stiffer springs . Most guys with those tires run 1100 -1300 lb springs. Your car will still dive now, just more!
With 30kg Spring , it equal to 1650lb rate
But swift spring tend to be on Lower frequency compare to hypercoil
I have to admit my shock Is pretty tired so before this season start I will rebuild it too !!
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Old 01-31-17, 09:25 PM
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Originally Posted by billyboy
With my rough and ready calc of divide by 2, he's more than 1500 lb already. Ride height and shock valving might have been my first port of call. Any bumpsteer correction on that thing?

Can't get over how popular it was with the Japanese to waste their time pop riveting - with what looks like aluminium rivets, rather than stitch welding back then.
That right , I am also rebuild my shock this season , and BTw the bump steer have not thing to do on how car will react on ride height at bump
I think what u mean is roll center

I bought this car from Japan , not suprise it come with a lot of Jdm style touch.....
Personally I will use roll cage to tide every thing up

Last edited by diyman25; 01-31-17 at 09:49 PM.
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Old 02-01-17, 01:01 AM
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Originally Posted by BLUE TII
The Japanese GT300 cars had to run this too tall for FD RX-7 tire size as well.

This is Revolution FD, but I believe is an ex-GT300 race car.
http://image.superstreetonline.com/f...ect-mu-caliper

You can see once they are back on correct diameter tires the modifications to unibody and body contour are not needed.
http://image.superstreetonline.com/f...ce-rear-bumper
The taller the slick , it get mote foot print under compression

The revolution build it from ground up
Using GT300 spec
But with GT500 power ( 13B Turbo instead of 20B pp) and time attack aero
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Old 02-01-17, 11:58 AM
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Yes, full slicks are going to be the fastest for a variety of reasons.

The Revolution FD is competing in Time Attack so must use full treaded street-able race tires (DOT-R in USA). So far no one is making a competitive Time Attack tire bigger (wider or taller) than 295/30-18 that I know of.
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Old 06-16-17, 08:25 PM
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did this solve your problem?

i'm considering running 645 or 661mm diameter slicks, but worried about the clearance as well.

can you detail how you modified it?

and why not just raise the ride height alittle?
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Old 06-16-17, 09:44 PM
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Originally Posted by Alpine
did this solve your problem?

i'm considering running 645 or 661mm diameter slicks, but worried about the clearance as well.

can you detail how you modified it?

and why not just raise the ride height alittle?
Yep
This solve my problems no more hitting frame rail at last race
As ridehigh Which is I am not plan to change any time soon
Since this ride hight work pretty good on my front aero splitter

If u plan to use slick over 640 u will have same problem like me ..... when I am using 650/640/17
I am perfectly fine but once to 680/650/18 the size and extra grip make it a night mare

Few thing u can do , like how I cut frame rail ,
Or using linner bump stop to have soft hit on frame rail

About rise up the ride hight , we need to go as low as u we can before we hit some thing , if u want rise up to fit the tire? Better switch to shorter tire, unless u get the almost for free....Any member cut their FD3s frame rail inorder to get proper suspension stroke-photo795.jpg
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Old 06-17-17, 06:13 PM
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did you notice a big benefit going from 17 to 18? worth the hassle to modify the apron?

Originally Posted by diyman25 View Post
Yep
This solve my problems no more hitting frame rail at last race
As ridehigh Which is I am not plan to change any time soon
Since this ride hight work pretty good on my front aero splitter

If u plan to use slick over 640 u will have same problem like me ..... when I am using 650/640/17
I am perfectly fine but once to 680/650/18 the size and extra grip make it a night mare

Few thing u can do , like how I cut frame rail ,
Or using linner bump stop to have soft hit on frame rail

About rise up the ride hight , we need to go as low as u we can before we hit some thing , if u want rise up to fit the tire? Better switch to shorter tire, unless u get the almost for free....Attachment 600102
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Old 06-18-17, 10:08 AM
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Originally Posted by Alpine
did you notice a big benefit going from 17 to 18? worth the hassle to modify the apron?
Is about tire wheel selection choice
For 280 and above is easier to find in my area is 18
So if u can find 650 under tire , use that
But once u go over that u really need to cut the frame rail to get 100% of tire
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Old 06-28-17, 04:11 AM
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You might want to just use some spacers on your bump stops if you just want to keep the tires off of the frame rails.

When are your tires hitting the frame rails?
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