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Discussion Starter #1
As some of you have known, my biggest problem with my R32 was the handling. So I have focused on that primarily. Reading RJTs thread on the suspension forum has confirmed my suspicion that indeed our cars werent designed for the most optimum track set-up.

The car will be used for the track and will be driven there. So I am installing lightweight carpet and insulation due to the heat after taking off my stock carpet.

The suspension work I had done:

Install steel bushing at the steering column.
PU bushes at the rack
PU bushes for the front lower control arms
MEGAN upper control arms(to adj camber)
Front traction control arms(to adj caster)
Rear upper rose jointed control arms
Rear lower rose jointed control arms
Rear traction arms
Solid rear subframe bushings.
Front and rear sway bars
Fender braces
Front and rear braces
Endless coilovers
HICAS delete
Roll cage to stiffen the chassis

Brakes

Dixcel FSR rotors for front and rear
Endless pads and fluid

Engine

Currently 305whp. Same dyno where a 997 GT3 RS dynoed at 355whp
Power FC
Z32 AFM
Stainless steel piping
Manual boost controller
290 fuel pump
Upgraded radiator
Upgraded oil cooler

So currently I just experienced a clutch slippage so I am changing to a Exedy stage 2. Only clutch they have in stock here so I decided to go for it.

My car at the paddocks.



Track day with the Porsche club




My radiator. I was able to retain the viscous clutch and shroud.



Rear section without the carpet.



My tow hook! I have been pulled before and its hard without one.



A fire extinguisher! After experiencing my 993 burning, this was a priority.



My new wheel. The stock wheel was too far.



Advertisement for my coffee and corned beef products!



My seats, Recaro Super Starks. Still have my old wheel.



My rear suspension arms.



My dixcel rotors. After doing a track day, am satisfied that I experienced no fade. They classify them as racing rotors, whatever that means.





My front upper control arms. Once I held on to the stock ones, these are much stiffer.





Oil cooler with the cigarette butts.



Old trackday pic.

 

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Nice car. Good mods too.

How do they do R32 LHD conversions?? I take it its a bespoke dash pad?

TT
 

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Discussion Starter #4 (Edited)
Nice car. Good mods too.

How do they do R32 LHD conversions?? I take it its a bespoke dash pad?

TT
Tnx. Yup. Basically they cut up the old dash and use fiberglass. RHD was allowed before but now are outlawed.

Forgot to mention that since my clutch was slipping, my boost was limited to .9 bar. So the 305whp is on the safe side.

My current group has a Subaru STI Spec C which has around a little more whp but has a real nice track set-up. Not to mention the lighter and stiffer chassis. He is the current Touring Car leader and his time is 1:52 at BRC, the track where we usually go. My fastest without my suspension and roll cage was 9 secs slower.

The fastest stock R35 was clocked at 1:50.
 

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The suspension stuff is nice looking, we don't really get the Megan Racing stuff over here. What geo settings did you get and how did they work out? If you are likely to see a wet track at any point the skylab controller is great and pretty cheap, and will let you stay out when all the Porsches have called it a day.

What do you have planned next, or are you going to track it some more as it is and decide what it needs after some seat time?
 

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Discussion Starter #6 (Edited)
The suspension stuff is nice looking, we don't really get the Megan Racing stuff over here. What geo settings did you get and how did they work out? If you are likely to see a wet track at any point the skylab controller is great and pretty cheap, and will let you stay out when all the Porsches have called it a day.

What do you have planned next, or are you going to track it some more as it is and decide what it needs after some seat time?
I might go CF in the hood and trunk lid. The thing is, the current shop who supplies the hood, doesnt have a hood with vents in them. So Ill talk to the owner if we can just put some simple vents.

I ordered the Megan parts from the US. What do you mean GEO settings? When you say Skylab controller, you are referring to something like which Full Race sells right?

Maybe keep it as it is for a yr then go EFR 8374, oil pump etc and with bigger brakes.
 

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I might go CF in the hood and trunk lid. The thing is, the current shop who supplies the hood, doesnt have a hood with vents in them. So Ill talk to the owner if we can just put some simple vents.

I ordered the Megan parts from the US. What do you mean GEO settings? When you say Skylab controller, you are referring to something like which Full Race sells right?

Maybe keep it as it is for a yr then go EFR 8374, oil pump etc and with bigger brakes.
Geo = geometry, alignment; camber, caster, toe etc

Yeah, skylab is for sale in the trade section of this forum. simpler and cheaper that the full race and ruzic controllers, still very effective.
 

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Discussion Starter #10
Geo = geometry, alignment; camber, caster, toe etc

Yeah, skylab is for sale in the trade section of this forum. simpler and cheaper that the full race and ruzic controllers, still very effective.
I set my front camber at -2.5 and rear at -1.5. Front caster is set at the most I could get. Actually rubs a little when I pull a full lock u-turn.

Front toe is neutral, while I am still deciding on the rear toe. Some say its better at a little toe-in while others say its better with a little toe out. Right now its neutral.

I think all of settings combined did a tremendous improvement coupled with the roll cage. If I were to isolate one improvement in GEO the most, I would think would be the caster setting. Improved turn-in feel. Quite remarkable with such a simple mod.

Ill look into Skylab. Tnx.
 

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I set my front camber at -2.5 and rear at -1.5. Front caster is set at the most I could get. Actually rubs a little when I pull a full lock u-turn.

Front toe is neutral, while I am still deciding on the rear toe. Some say its better at a little toe-in while others say its better with a little toe out. Right now its neutral.

I think all of settings combined did a tremendous improvement coupled with the roll cage. If I were to isolate one improvement in GEO the most, I would think would be the caster setting. Improved turn-in feel. Quite remarkable with such a simple mod.

Ill look into Skylab. Tnx.
Id stick to either neutral or tiny bit of toe in on the rear.
For the front, neutral or try a tiny bit of toe out.
 

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Discussion Starter #13
RJT thanks for your inputs. Any updates on your study on our double link front suspension system?

AlexJ - The Skylab seems to be a good kit, especially for the price. I have never driven the car in the track wet. But my experience is either coming in to fast, and giving throttle to early, which results in my rear end kicking.

I have measured my speeds in the corners with my friends STI Spec C and it seems I can, at some corners, have the same speed.

Am sure this will help. I hope to get it soon.

Here is a vid, running on .6 bar because of a boost leak as I found out lately. Still have my old wheel on it thats why my arms are so extended! Cant wait to try my new wheel.

https://www.youtube.com/watch?v=aGZsgWTvin4
 

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Yeah I measured all the points of the front suspension and put it into a simulation program that I found.
That was hard work!!
Then I worked out what it would be with a typical lowered car with static neg camber.

Worked out all the kpi and caster, scrub roll centre, swing arm length etc etc.
Seems it runs a fairly high amount of kpi, especially with the added static negative camber.
KPI actually adds positive camber in a turn, which is why it is a good idea to get as much caster as possible to balance it out.

It was a good and interesting exercise, and it told me that its not all that bad of a design really (r33 remember).

Minimal (but some) camber gain and no lateral scrub within the normal working range of the suspension.

But the long and short of it was, We cant bloody change any of it anyway without a massive redesign of the whole front suspension. Especially if rules state to use original pickup points.

It would be nice to be able to reduce the kpi, and also raise the roll centre without shortening the swingarm length (more camber gain), but we cant....

It also taught me that there is no possible way to have the optimum setup, everything is a tradeoff. Like reducing the kpi would increase scrub radius etc etc.

I am going to looking into creating a whole new knuckle/upright with the pivot above the wheel instead of inside the wheel. This would reduce the kpi but more importantly save a shed load of weight.

But most importantly I think it is a must to understand what effects each adjustment/part we use, has on the rest of the suspension workings.
I think that is what led me to create that other thread.

For instance, I fitted roll centre correcting spacers to the front suspension. However it had a massive effect on bumpsteer without addressing the angle of the track rods (There was nearly an inch of toe change throughout the whole travel- droop to bump!!)
 

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The suspension stuff is nice looking, we don't really get the Megan Racing stuff over here. What geo settings did you get and how did they work out? If you are likely to see a wet track at any point the skylab controller is great and pretty cheap, and will let you stay out when all the Porsches have called it a day.

What do you have planned next, or are you going to track it some more as it is and decide what it needs after some seat time?
Those bits looks pretty identical to the hardrace stuff. Apex performance sell that.
 

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Those bits looks pretty identical to the hardrace stuff. Apex performance sell that.
You're right, although someone posted up some close-up pic of them side by side here or the gtr canada forum and they are marginally different in the strengthening gussets and that sort of thing. All much of a muchness though.
 

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Ahh right. Yes looking closer, the hardrace rodends have dustboots and the clevis bits are painted too.
 

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RJT thanks for your inputs. Any updates on your study on our double link front suspension system?

AlexJ - The Skylab seems to be a good kit, especially for the price. I have never driven the car in the track wet. But my experience is either coming in to fast, and giving throttle to early, which results in my rear end kicking.

I have measured my speeds in the corners with my friends STI Spec C and it seems I can, at some corners, have the same speed.

Am sure this will help. I hope to get it soon.

Here is a vid, running on .6 bar because of a boost leak as I found out lately. Still have my old wheel on it thats why my arms are so extended! Cant wait to try my new wheel.

https://www.youtube.com/watch?v=aGZsgWTvin4
track + cage + no crash helmet = YIKES!

I'm far from an expert but... have a look at this on board of me at Silverstone - it's still a bit damp and I have the Skylab turned up a little to give some more 4wd.


Not my finest work - the logger ran out of memory before the track fully dried and I got my mojo going - so I can't share the full extent of my "mad skills".

I think I'm turning in a little later and on the gas much earlier than you do, I'm almost looking to accelerate from about halfway between turn-in and apex, that really helps prevent understeer approaching and past the apex. At Copse and Stowe (the two high speed corners) I'd understeer horribly unless I had a decent amount of throttle on.

On the hairpins I'll trail brake to get some rotation going between turn in and apex and then gas from their to keep it rotating. Neutral throttle = understeer.

We're not talking opposite lock power slides everywhere just some oversteer slip angles that mean you can wide some lock off sooner and help out the front tyres.

Here's one of a calsonic rep r32 at Snetterton doing similar but with more power :)
 

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Discussion Starter #19
Yeah I measured all the points of the front suspension and put it into a simulation program that I found.
That was hard work!!
Then I worked out what it would be with a typical lowered car with static neg camber.

Worked out all the kpi and caster, scrub roll centre, swing arm length etc etc.
Seems it runs a fairly high amount of kpi, especially with the added static negative camber.
KPI actually adds positive camber in a turn, which is why it is a good idea to get as much caster as possible to balance it out.

It was a good and interesting exercise, and it told me that its not all that bad of a design really (r33 remember).

Minimal (but some) camber gain and no lateral scrub within the normal working range of the suspension.

But the long and short of it was, We cant bloody change any of it anyway without a massive redesign of the whole front suspension. Especially if rules state to use original pickup points.

It would be nice to be able to reduce the kpi, and also raise the roll centre without shortening the swingarm length (more camber gain), but we cant....

It also taught me that there is no possible way to have the optimum setup, everything is a tradeoff. Like reducing the kpi would increase scrub radius etc etc.

I am going to looking into creating a whole new knuckle/upright with the pivot above the wheel instead of inside the wheel. This would reduce the kpi but more importantly save a shed load of weight.

But most importantly I think it is a must to understand what effects each adjustment/part we use, has on the rest of the suspension workings.
I think that is what led me to create that other thread.

For instance, I fitted roll centre correcting spacers to the front suspension. However it had a massive effect on bumpsteer without addressing the angle of the track rods (There was nearly an inch of toe change throughout the whole travel- droop to bump!!)
What is your background?
 

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Discussion Starter #20 (Edited)
AlexJ - I was wearing my helmet then I realized I couldnt pull my window down, so I took it off. While driving I was able to pull the window down..LOL.

My car in that vid was running .6 bar so it was really weak. I have trouble with gearing in that track in some turns cuz when I am on 3rd, revs seem to take ages to get higher.

But I had a recent re-tune so I will take it again once I put my new clutch.

I dont have the understeer problem, but more on oversteer. Hmmm, maybe its my thick rear swaybar. But let me install the skylab and see how it goes.

Your driving is good!

Love the Calsonic rep! Cant wait to upgrade my engine.
 
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