crysis

bumping this

what are the solutions to getting off-the-shelf, plug and play 250lb/175lb springs over some tokico shocks/struts?

I've done a day and a half of search and there are a lot of home-brewed solutions, but I cant find a solid answer.

If custom is the route, what do we have to request?
Inner diameter
Spring length
Spring rate
(??)icecream cone front spring shape?(??)

Carl

iTrader: (2)

The spec7 springs currently being advertised in the for sale forum will do exactly what you want.

crysis

If they're spec7 spring rates, they're much softer than what I'm looking for.

Carl

iTrader: (2)

I think the spec7 front rate is around 225. The rear is probably around 125lb. The 175 rear is closer to the pro7 rate, but they are typically paired with 350-375lb. I think you will be somewhat unbalanced with the rates you are looking for.

You seem to know what you want though. For 175 get the ground control pro7 rear springs or go to blue coil (Suspension Spring Specialist, Inc.) and get 8" long springs in the rate you want. At blue coil they come in 25-50 lb increments from 100-500 lb. For the front I don't think you have any choice but to convert to coilovers and get 2-1/2" springs. That is a pretty clean conversion, not particularly home-brew.

Carl

crysis

I was afraid of that (the ground control kit)

Do you know if 5x8" would be drop in? Or would it be too low with the stock length being closer to 12-13inch? Did a bit of searching on that as well and it seemed people were getting taller spring perches to fit the 5x8"

crysis

Did some digging and pro7 ran 5x9" 175lb in the rear. wondering if 8 is too low for the stock watts link

Freeskier7791

I think it will still work ok. I am going to try 300 lbs in the rear but I am building a v8 powered drift car...so probably the opposite of what you guys are trying to achieve handling wise

crysis

ah yes. one thing to look out for when putting it low is there's a lot of wheel hop due to the watts link. AE86 guys have a kit that makes the arms equal length and help solve that binding, but i'm unaware of one for the FB.

Carl

iTrader: (2)

5x8 is low, but it works fine in my ITA car. You can add spacers though if you want it higher. You can also buy a lower rate 13" long spring and cut it to the length you want. Just look up a spring calculator online to figure out what spring rate to get so that you can cut it to the length you want and end up with the spring rate you want. Pretty straight forward. Then again the Ground Control pro7 rear spring rate is 175lb, I think, and it has a bunch of dead coil that you can cut to give you the length you want.

Carl

iTrader: (2)

After seeing the other posts (which weren't there when i started my response early this morning) 8" might be too short for the watts link. I have tri-link rear suspension with my 8" springs.

crysis

Ah maybe I'll order the 9" just like the pro7 cars, and the 300lb fronts in that weld on coilovers kit by gc. Do you need camber plates there or will the metal hats sit in the spring seat fine on top?

Thanks for all this help! I'm finding FBs require quite a bit of research lol

Carl

iTrader: (2)

No you will need to do something at the top. What I have done on our ChumpCars (just made 2 last week) is to cut up the stock upper spring perch to use the "bearing washer" at the top. That is welded to a 1-3/4" washer and then on the opposite side is welded a short piece of 2.25" tubing to keep the spring centered. That has worked for many hours of racing and multiple crashes (by my teammates, not by me). The attached picture shows two. One is upside down so you can see what they look like. They bolt into place just like the stock upper perch and use the rubber in the stock top hat for flexibility.

MRLQ2U

Hoping that someone from this thread is still up for talking about this. I'm running 375# on the fronts with Tokicos and coil overs. I have 290# in the back with 5X8 coils. I want to go to the TTT rear coil over (+weight reduction, +ride height adjustablilty) but I'm having a tough time understanding how to apply to the motion ratio to calculate the rate when switching from standard coils to coil overs. I see that Beansncornbread mentioned the coil over question but I couldn't find a response that mentioned suggested rates.

So...anyone running rear FB coil overs and, if so, what rate are you using?

My car (Trixie) is 1950# without me in the seat, running Avon 15"x10.5"x23" slicks.

Thanks in advance!

Alex gslse

I am planing on getting ttt coilovers sometime soon and I was thinking 325 front and 175 rear but I was wondering if it would be good for a summer daily that I might be sliding around in once in a while

sa7

iTrader: (13)

325F and 175R should be fine. It's not far off from what I have. I usually try to daily my rx quite a bit in the summer and I have 275# fronts and 150# rears. The car handles well on the street and isn't too harsh, and it does well in autocross.

Alex gslse

Ok thanks and I was also wondering how to rear is because I see a lot of people saying the rear strut towers aren't strong enough to hold the weight of the car and they will get messed up but I have never seen anyone post pictures of ones that broke through on a fb Rx7