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clarkspeed last won the day on December 7 2022

clarkspeed had the most liked content!

About clarkspeed

  • Birthday 04/22/1965

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    Downtown Orlando Florida
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    Building and racing cars. Anything automotive. Guitars. Local music played in local clubs.

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  1. 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.
  2. 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.
  3. 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.
  4. 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.
  5. 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.
  6. 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.
  7. 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?
  8. 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.
  9. 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.
  10. 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.
  11. 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.
  12. 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.
  13. 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
  14. 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.
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