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Are 7J Rears enough for 240hp?
SeanStone - 6/7/11 at 09:49 PM

As the title reads, would 7j's be sufficient for putting the power down, or would 7.5/8's be better?


austin man - 6/7/11 at 10:01 PM

the racers use 9" I believe gives better traction


dhutch - 6/7/11 at 10:05 PM

I heard 10j was essential for anything over 100bhp....


franky - 7/7/11 at 05:27 AM

quote:
Originally posted by SeanStone
As the title reads, would 7j's be sufficient for putting the power down, or would 7.5/8's be better?


I use 7j with 320bhp and have no traction issues at all.


alistairolsen - 7/7/11 at 07:34 AM

Depends entirely on your choice of tyres, ALWAYS start with tyres and work back


franky - 7/7/11 at 07:43 AM

Just to add, I use toyo r1r's in 225 on the back. Same compound as r888's but with added wet weather treatment and they're cheaper than r888's too.

I don't know why you'd need wider to be honest.


tomgregory2000 - 7/7/11 at 08:00 AM

9j on mine with 275 kumho v70 in med compound and 321bhp and loads of torque (remember its the torque you have to worry about)

and once upto tep they are good, cold they spin up


russbost - 7/7/11 at 08:05 AM

"I use 7j with 320bhp and have no traction issues at all"

There is either something major wrong with your right foot or you've never driven it in the cold & damp!!!


franky - 7/7/11 at 08:13 AM

quote:
Originally posted by russbost
"I use 7j with 320bhp and have no traction issues at all"

There is either something major wrong with your right foot or you've never driven it in the cold & damp!!!


Quite the opposite, we did some performance testing yesterday on a damp road inbetween downpours, Did some 0-60 timings which came in at 3.6seconds, Looking at the rubber left on the road it was only for about 3meters each time. I guess having a linear N/A helps, the engine makes very good torque but it doesn't come in the same way a turbo does.

If the OP is running a s2000 engine with 240bhp I can't see why he'd need wider? The S2000 engine is great as its a revvy motor too.

I guess traction is in setup too however I think most praise should go to the rubber.


Minicooper - 7/7/11 at 10:47 AM

Franky,
What rear suspension do you have?

Cheers
David


sdh2903 - 7/7/11 at 11:19 AM

Out of interest is that using the traction/launch control or purely on the right foot?

quote:
Originally posted by franky
quote:
Originally posted by russbost
"I use 7j with 320bhp and have no traction issues at all"

There is either something major wrong with your right foot or you've never driven it in the cold & damp!!!


Quite the opposite, we did some performance testing yesterday on a damp road inbetween downpours, Did some 0-60 timings which came in at 3.6seconds, Looking at the rubber left on the road it was only for about 3meters each time. I guess having a linear N/A helps, the engine makes very good torque but it doesn't come in the same way a turbo does.

If the OP is running a s2000 engine with 240bhp I can't see why he'd need wider? The S2000 engine is great as its a revvy motor too.

I guess traction is in setup too however I think most praise should go to the rubber.


franky - 7/7/11 at 11:32 AM

Just my right foot, the Traction/launch control has a software bug that causes the car to misfire if connected, something to do with the data cable going to it, hoping to get it sorted in the next few weeks.

Rear is adjustable GAZ shocks, bmw LSD+driveshafts.


Minicooper - 7/7/11 at 11:42 AM

franky,
Thanks but what I was interested in, is it semi trailing arms, irs, de dion

Cheers
David


franky - 7/7/11 at 11:54 AM

quote:
Originally posted by Minicooper
franky,
Thanks but what I was interested in, is it semi trailing arms, irs, de dion

Cheers
David


Oh sorry, its IRS.


Minicooper - 7/7/11 at 12:00 PM

quote:
Originally posted by franky
quote:
Originally posted by Minicooper
franky,
Thanks but what I was interested in, is it semi trailing arms, irs, de dion

Cheers
David


Oh sorry, its IRS.


Thanks Franky


DRC INDY 7 - 7/7/11 at 09:39 PM

I have 195/50/15 toyo 888 on the rears 7j rims with nissan 200sx turbo engine running between 215-250 bhp with the mods thats on at the mo


RazMan - 7/7/11 at 10:23 PM

8Js and 230bhp - no problems with grip except on very wet days.