clarkspeed

Well, I had some major setbacks the last couple months. A triple heart bypass put a little delay in the build progress. I thought I was a little young for this but such is life with family history. Feeling much better now 6 weeks later but still on the recovery. Not really ready for heavy lifting yet so trying to complete some of my easier projects. Anyway, here is a pic of the new Redshift dampers that arrived just before my hospital visit and a pic of the front struts I am prepping for the dampers. Sorry for the crusty bed sheet they are staged on. I am motivated to get stuff done, so hope to be back on the car in another week or 2. The dampers are essentially custom valved BC coilovers to my specs. The single adjustment controls both compression and rebound combined. They came with full dyno graphs. I have to say the BC hardware looks to be of very high quality in the adjusters, hats, and camber plates. Chris at Redshift was incredibly patient and answered my 20 or so questions with detailed explanation and honesty. He seems to like emails to communicate but is very responsive. Can't wait to try these.

I jumped ahead and looked at the section on splitters. Seems he was a little late to the game. But when he tested a small one it ripped off his car. He then goes on to explain how it works and how to properly shape one. Seems a slight curved bottom is better than flat. And some profiles of leading edge are better than others.

Thanks Jon, This book seems to be everything he has done for 25 years all rolled up and adjusted to the latest technology of the last year or so. I'm about 1/2 way through but I can't find any aero mod you can do to a production car he doesn't cover in depth somewhere in the book. Yes, he emphasizes no aero modifications should be made unless you measure the effect. It may not be what you expect and may upset the aero somewhere else. I am trying to wrap my head around how much lift a car, any car, produces. So for a production body style, you are basically trying to reduce lift, not create downforce. Exception being major mods like splitters combined with diffusers and wings. And as expected, lift and drag are 2 completely different things. Air dams reduce drag, splitters increase downforce forward of front axle only which can really lighten up the rear axle due to the lever arm. One example on an air dam he tested a 4" deep and a 9" deep. The 4" reduced drag almost as much as the 9" and left greater ground clearance. He tests plenty of bolt on parts in the book and proves they work as intented. So obviously there are bolt on parts designed for specific cars that benefit lift or drag. But if you have to make choices or optimize the part, better be ready to test. Obviously a rear spoiler works on an early Z. But how tall and what angle is best to optimize?

Well I am going down quite a rabbit hole now. I recently ordered Julian Edgar's newly released book. Very down to earth and all practical solutions to testing and tuning production car aero on a tight budget without CFD or wind tunnels. For example he uses a throttle stop to measure changes that affect drag. Stop the throttle at 10 or 15% and measure top speed at roughly 50 or 60 mph. Make an aero change, then check top speed again. Not cheap, but 500 pages packed full of info and lots of pictures. Highly recommended if you are looking to reduce drag and lift on your car.

Sorry, late to the party on a dusty old thread. The Toyota S12+8 solid rotor calipers accept a 2nd gen rx7 pad with just a light grinding on the metal backing plate tab that sticks out. I can't recommend the "best" pad for an application, but those rx7 pads come in any flavor you desire. You can search for the thread or I can provide more info if you need.

Yea, I could see that happening. A lot depends on the volume of the slaves. Luckily there is more than one way to skin the horse.

Bleed F and R simultaneously? Don't understand. Usually the balance bar self adjusts and allows you to bleed each wheel as normal. Feels wierd, but works fine. I don't do anything different with dual master as I would with a single. Let me know what you are thinking. Usually a non issue getting rear too strong. I tend to experiment with rear pad materials if things are too outa-whack. I have run street pads in rear before.

Couple pics. I had to fab my own pilot bearing. Bought something close from MacMaster Carr. Drilled it and honed the last .003" out to fit the tranny input shaft. Also got a very large blast cabinet into the shop on a trade. Next job is to blast another set of strut housings for paint and then the exhaust system. Many more pics coming.

What he said.

Cool. With this type of build I would expect shimming the body somewhat just because the body may not be true. I hope your final assembly is visually acceptable. Curious what you are shooting for for Ackerman. With the steering rack located in front of the front axle, you are limited on Ackerman %. Good luck.

Sorry you are having to go through such a extensive quality inspection, but the time spent should pay back later. Some comments. 1. Record all your measurements and if you can add a feature to make it easier to repeat the measurement it will save time later. Like chassis center. 2. Are your bump steer measurements all in mm? A good goal is less than a mm over roughly 25mm of wheel travel. I think I would rather have the final rack in there to pass judgement. 3.might be easier if you jack the chassis and keep the wheel fixed to measure bump steer. 4. I didn't fully understand your chassis alignment issue but sounds like the control arm inner pivots are aligned and centered both front and rear? Just not square with frame? Not cool, but if the mounts are all aligned then kinematically the suspension should work as intended. Usually critical frame measurements are taken from the suspension mounts front to rear and X cross. 5. Looks like you have standard GM control arm bushings in there. Are they rubber? If so you might be getting some flex in some of your measurements. 6. Not sure of your ultimate goal, but if you plan on making a lot of alignment changes in the future you might consider recording all the coordinates and putting in a software program to simulate the impact of your changes instead of measuring after each change.

See above. R180 moustache and R200 are different and can be mounted backwards I think. Always good to check if halfshafts are in alignment. You will also need to match angle of diff with angle of tranny equal and opposite.

If you dig around on the forum you can find an excel roll center calculater I posted awhile back. It works for S30 z's. I still use it for a quick estimate. Yes, Greg uses 2 spacers welded together, and he runs a very low ride height. But I don't know what his front RC height is. I could probably guess. I'm sure it is above ground. And no trickery in the rear. His rear inner and outer control arm pivots are at or close to OEM location. Possible he runs higher RC in front than rear. I have a 1.2" spacer I bought a couple years ago from TTT. I looked on their website and not see it for sale anymore.

I went ahead and bought a pair of 1" spacers not knowing any 3/4 existed. Let me measure where I exact need (nominal) to be and I will let you know.

Sure thing. I will try to describe without diagrams. As you add caster, imagine strut top moving rearward, it raises the steering link angle with it. So the arm to tie rod link is now much higher in relation to the control arm ball joint. I did not plan for that. Didn't even cross my mind. So now, even with all my adjustability, I don't have a way to get the tie rod parallel to the control arm, which is needs to be close to eliminate bump steer. So my choices are 1) slot the inner control arm pivot down, not sure I have enough room 2) raise the steering rack, not possible 3) add more spacers to the tie rod to steering arm rod end, not possible, hits the wheel or 4) remake my adjustable steering rack adapters. I chose #4. I think there is a picture of them in this thread somewhere. The control arm problem is a little harder to describe because of my design. I have a 1.2" bump steer spacer AND a pin below the steering knuckle that drops the ball joint, spherical bearing actually, in relation to strut and steering knuckle. This is all about control arm angle which drives roll center and camber gain. I have just a little TOO much correction resulting in a large downward angle on control arm and a front roll center quite high. To correct I need about a 3/4" bump steer spacer so I will mill down a pair after I am sure of the dimension it needs to be. Too much information?

One step forward, ten steps back. Sorry no cool pics to post. Dealing with all my latest problems. Radiator outlet hits the alternator, oil pan hits the steering rack, exhaust hits the brake lines, control arm geometry wrong in front, steering geometry wrong, excessive bump steer, need a custom pilot bushing, new damper direction and renovate another set of strut casings, maybe more I am forgetting about. Had to pull the engine back out and now methodically fix each problem 1 by 1. The immense frustration only lasted 3 or 4 days then back at it. Mentally hard pushing through 10+ major problems I didn't plan quite well enough for. On plus side, all the plumbing and electrical done. Engine done, induction system done. Exhaust still needs a coating.

Or if you really want to be sophisticated, buy a throttle by wire pedal. I see many of the EFi systems support it now. Program your own linear ramp.

That is a great idea. That would make 50's work on street fairy well. In my opinion only without direct supporting data, think a large TB with a highly ported intake on EFI makes max hp from a NA L6. My intake is ported so much I broke through the walls. I don't think I measured over 6 (in. Mercury?) Vacuum with throttle cracked open. I also highly suggest a VERY OPEN filtration system. Can't be too large. What are you planning upstream of the Jenvey's? I saw Troy Ermish put a 5" diameter cold air on a race 4 cylinder.

50mm ITB's! That will be an on/off switch, but I personally think will make the power. Forget the MAP. Turbos are different. On a NA motor you can kind of sneak up on knock. You will hear and feel it with any muffler at all. Probably without. If unsure you can start with octane boost on top of premium and then back it out. I hate retarding timing on an NA motor.

A lot depends on your induction system. I have 48mm ITBs with a short manifold. There is not enough vacuum to do anything with so no MAP for me. If you are using a 1 into 6 manifold or a stock based manifold, definitely use it. And most of the race guys I know avoid knock sensors. Maybe they are better now but in the past false vibrations would cause them to reduce timing and power. Street car on the hairy edge may be needed. I can't speak for the closed loop tuning stuff. I don't know anyone who has used it to tune a true road or drag race car. I usually tune WOT fuel curves on a dyno. If really stumbling off throttle I might to a 1/2 throttle run. Then fine tune part throttle and throttle tip in based on data collected while driving. Don't think I would spend any money upgrading an SDS. That would not be practical. This thread got me looking at the Speedduino again. I understand sensors, wiring, and Tuner Studio so much better now.

Believe it or not, I am still running a SDS on mine. Plans to upgrade but have not justified it yet. Lots of good systems out there now. I've also heard good things about the Maxx. Haltech has been a solid product for many years. Troy Ermish recently posted he dropped Electromotive because of lousy support. I've tuned Mega's and they are solid too. Speedduino looks really neat for a simple system. Really tough to decide based on features vs. price. I think the higher level stuff gets deeper into traction control, wheel speed sensors, trans control, ABS, telemetry, and other motorsport needs. Top of the line is a Bosch. Most of the pro production race cars run them. I looked into their features 1 time and thought I will never use any of that! Luckily any system that is good for the street is probably way more than you need for a 50 year old race car. https://www.bosch-motorsport.com/content/downloads/Raceparts/en-GB/109903243.html

Need some more details to troubleshoot. Did it idle good before? What changed? What EFI computer? Do you have an O2 readout? What kind of TB/intake manifold is that? Also agree with your other post.

Nice work. That looks like a potential side business.

There is only so much room to work with. If the inside is a 1/4" or so away from your strut, then the outside edge will fall where it may. I usually shoot for 0 or a little interference on the inside and use a wheel spacer to compensate. Can't give exact numbers because tire size and suspension travel make a big difference. Once you go to a 8+ rim without flares every 1/8" counts. Best to remove spring and jack wheel through full travel. If you already have the Rotas mounted up, you should be able to predict what a change in offset or width will do for you.

I've been working but not much to show. Dealing with many interferences in the engine bay. So it is all rework at this point. Hopefully some success and photos soon. In the meantime, clutch parts arrived. Ordered the Flywheel from UK and it is a nice unit. Clutch is 7.25 Quatermaster 2 disk V drive. I went with 7.25 because my tranny ratios are soo tall. Pretty sure I would burn out a 5.5, just driving around pits. But not I need to order 8mmx1.25x45 bolts to mount. TTVracing.com