wholelottahustle

I thought I would post this here since my question is specific to the FD(mods feel free to move this post to the suspension area if you feel it is more appropriate)

My current suspension setup:
Racing Beat Front/Rear sway bars
Koni Yellow Struts(mileage unknown, car had them on when I puchased it, 61k miles)
Stock Springs
Alignment per Howard Coleman's reccomendations


1) My friend who took my car for a drive (and was very impressed with the FD having never driven one before) mentioned that he felt that the front end bounced around a little bit on corner entry/exit. He mentioned the solution would be pre shortened struts or going with coilovers.

Would there be any other reasons that may cause this bounciness in the front end?

2) I am considering Tein Flex vs. Ground Control coilover Kit. I will be going with 8/6 spring rate reccomended by Howard Coleman in this thread https://www.rx7club.com/suspension-wheels-tires-brakes-20/howard-colemans-fd-chassis-setup-723617/.

There is a significant price difference between the two setups, especially considering the fact i will have to purchase different springs for the Tein Flex which come with 10/8 spring rates.

Is there a compelling reason to go with one setup over the other?

Thanks for any input you guys. This forum is an awesome resource.

Chris

MX3

iTrader: (4)

You'll definately pay more for Coilovers.

If you'll be taking your car to the track or racing I'll suggest you go with the Coilover kit. Since you'll have options to raise or lower as you like.

I'd say go with springs. There are people here who've done just springs.

Also check with DJSeven. He's did springs on his RX-7.

gracer7-rx7

iTrader: (16)

This thread is more appropriate in the suspension section.

What did your friend mean by bounce? Can you describe the scenario in greater detail

The fact that you friend mentioned coilovers as a solution makes me suspect that he doesn't know a lot about suspension systems.

I generally associate a 'bouncy' suspension with a worn shock. When the shock is worn, it can't control the body movements as well.


IMO - If you aren't tracking the car and you aren't already at least an intermediate level driver, you are wasting you money with coilovers and installing a set will probably make it more difficult for you to learn the car with the stiffer suspension setup. The benefit of coilovers is that you can corner balance the car. If you aren't at the level where you need to corner balance the car, you really don't need 'em.

I'd suggest getting a professional that knows suspension check out your car before spending $1,500 on coilovers.

I run Konis and GC. used to run Konis and springs. Easily serviceable setup with the Koni shocks. Springs are cheap at $50 each new and you can find them used for $75 pair if you want to change rates. Shocks can be used with regular springs and then move up to a coilover spring when ready.

wholelottahustle

Gracer, thanks for the input!

The way he described it was that entering in a (bumpy pavement) corner the front end became "unsettled" and didn't feel "planted". I don't know if this description helps at all. this was not on a smooth track.

By no means is he a suspension expert. One possible scenario he gave me for the problem was that depending on whether or not the aftermarket strut was the proper length for the spring, when the car becomes un weighted over a bump the spring may have no compression on it causing this feeling of being unsettled. He tossed out the suggestion of "pre shortened struts".

I believe that the Koni yellows have different spring perch heights(low, med, high) so I thought he could be correct depending on which perch the springs may be mounted.

What causes a shock to become bouncy when it is worn?

I know the eibach pro-kit springs are well regarded so I'll check those out.

Thanks for the input.

gracer7-rx7

iTrader: (16)

This kinda scenario is hard to diagnose on the internet...

The FD has a pretty stiff suspension stock. Stiff suspensions don't always handle bumpy pavement well and can feel unsettled as a result. It becomes worse as you stiffen the suspension so coilovers or stiffer springs is a move in the wrong direction if you drive a lot on rough roads. So w/o being in the car its hard for anyone to tell you whether its normal and due to the rough pavement or if you perhaps have a worn or blown shock.

A shock can be bouncy b/c it looses its ability to soak up the bumps. If it can't soak up the bumps, it can't keep the tire in contact with the road surface. Shocks wear with age or sometimes a big hit will damage the internals piston seals. The oil in the shock also wears out over time. Check GrassrootsMotorsports.com online articles for an article on shocks.

I ran Konis with stock springs for a while and ran them at all 3 spring perch settings. I thought it was a good pairing in terms of ride quality and handling for the rough NYC area roads I drove on.

Where in CA are you? I'd suggest getting another opinion or two before spending money on the wrong parts.

jkstill

iTrader: (11)

If you go with the Ground Control setup and use 800/600 lb springs, you may want to research some different shocks to use, or possibly get the Konis rebuilt for the higher spring rate.

Everything I've ever been told and read about Koni yellows is they can't handle that much spring out of the box.

I run 550/450 with GC and Koni Yellows, as per GC recommendation.

wholelottahustle

Thanks gracer. I'll definitely do my homework before I make any decisions. I live in the East Bay.

Jkstill: Just to clarify I would be going with an 8/6 kg spring rate which equals 432 front and 378 rear.

wholelottahustle

from post #44 of Howard Coleman's suspension thread

"summary: for a dual purpose FD.... either Eibach Pro Kit for near stock sized wheels/tires or a coil over at 8/6 or 450/350."

gracer7-rx7

iTrader: (16)

I'm on the Peninsula. Let me know if you ever want to meet and compare. I'm running 450F/350R on my coilovers.

There are a few good shops around here that can offer a professional opinion.