ZROSSA

Cool. Like it........a lot. Are you going to finish triangulating the Back bone? Douglas

Jeff, I not to sure on the scrub radius thing (will look it up) But when you think about it a mac. Strut might be the easiest thing to use. Just set it up with as much adjustment as you can get with camber plates and you can go from street to race in no time. I think the scrub radius is where a line would hit the ground if drawn through the top of a strut then trough the ball joint. You want zero and the normal would be negative (more towards the center line)with the standard set up. I guess the wider the tyre the larger the difference. There is a way around this however. You need to space the hub away from the ball joint so you can run wheels with the offset biased towards the inside. I did this on my 75 Corolla. It has bilsten struts out of a sentra and s4 rx7 hubs. Funny combo, but cheep. We just figured out where every thing needed to be and welded up spacers from the strutt to the hub. Douglas

Got a grinder? Just get a thin cut of blade for it. That all I have ever used. Douglas

No prob. Glad my half pissed ( was Friday night after all) coments were of some use. Douglas

Mike, Whats the story with your "rear arm fix". Did you run out of adjustment? Douglas

Hate to say but its not triangulated at all! You should have joined the firewall bars to the top of the strut. The other thing to keep in mind is that the forces involved are high. The fact that you cant bend the bars unfortunatly means nothing. Think of it this way. You cant pull or push the strutt towers but you know they move with the forces involved or you wouldnt bother naking the bars. Douglas

Clint, Havent done it but going to comment anyway. I tryed to put a supra rear end in my 75 corolla 4 years ago. It a circut car only and in the end it would have been much heavyer with the IRS. I was under the impression that you were going to want to drive this on the streets every so often, So you will need a cert. The subframe mounting points on the skyline dont come anywhere near the ones on the s30. I think you would need to add a lot of metal to the mounts. The other thing is that looks like a hicas rear. I guess you would have to run that locked out so then the rear wouldnt work as intended and you would have to spend a whole lot of time and money sorting it out. Its also wider. In the end it comes down to your skills and resources. It would be a cool swap but I dont think it will be any better on the track then a well modified standard set up. On the track you will run springs that are stiff enough and wont allow the standard set up to get into the range where it becomes compromised. The skyline set up will need a lot more work to get it track ready. Start buy thinking about the number of rod ends you will need. Douglas

Howdy, You have still ignored what the lads have been saying. If you want this to be strong then you will need to get some triangles in there. I would do the radiator suport like a small space frame. I still dont see much of a benifit in joining the struts to the radiator support. I would drop them down to the front suspensiom mounts. Try not to join any tubes to the middle of another tube. It just creates a place for that tube to bend. Douglas

Very nice indeed. You wouldnt happen to know of a good place to figure out the volumes needed? I think I might do something similar for the corolla. Douglas

We have covered this in the past. Have a search. I put some measuremets in the old post. Douglas

Richard, Are you getting tyre temps.across the tyre after a lap? I think the inflation and camber issuies are relavent but the grain patern on the ouside edge is probable a clue to the answer. Not that I know It. How do these compare to other tyres you have used? Another thing to think about is that if you have improved the tyre resently then the rest of the set up might not work with them. Douglas

There is probably a good reason why Johns manifold performed better. Have a look at the runners. They are straight. To do I.T.B's on the l6 would need bent runners or 6 individual bodies. Very expensive. I belive the ITB's will make more power on an engine designed to use them. That means that the port spacings would be a equal distance apart. When the world rally car f2 rules changed a few years ago, no longer alowing itb's, the cars lost about 15 h.p if I remember correctly. They were reving these things close to 9000 rpm though and I cant remember if they had to use the standard manifold. Douglas

I think his was a straight 6 out of a skyline import. Douglas

Cool, Where are you picking the car up from? Is there much of a difference between the rb20 and rb25 heads. rb20 might be a cheeper option if valve sizes are similar or if you have to do major head work anyway. It looks as though there are going to be a few fast zeds around. Might have to form a club and get in some track time. Douglas

911/914 with a small block. I have a soft spot for the triumph's. First car was a herald. A sedan version of the spitfire if you like. Rolled it. Wouldnt mind another. Mabye with a big four like the toyata 3rz taanji's keen on. Douglas

Good thinking. Might have to look into that. Douglas

Jamie, I have heard of this being done but only on the exhuast valves. This will also bias the combustion chamber towards the exhuast side which is a good thing. Douglas

Looks doable, I wouldnt worry about the roof line yet. You can do things with paint that can fool the eye around the wind shield that will make look more like the 575. Before you get to into it have a think about how much lower you want to run the car. The ZX rear suspension wont want to be lowered to much unless you want to do some pretty major modifications. Douglas

Chewie, Dont forget that the gtc was based on the 575 maranello. Get the standard dimensions for that and it will give you a real idea what your "fudge" facter is. The standard car is shorter, higher , heaver, and narrower. Probably not far of the sixe of the ZX. Douglas

Didnt mean to point anyone in the wrong direction. I guess there is a point where boost takes over from mechanical compression. Still you need the combustion chamber to burn properly, no mater what the engine. Have a look around that site James. Interesting reading. Douglas

Jamie, Go have a play around http://www.theoldone.com Study all the 4 valve heads you can. I think you will find that you will want to keep the quench pads, particularly the intake side, so that the combustion chamber has a bias towards the exhuast valves. Get your chamber right and you can run lots of compression with a turbo. Douglas

Pete, Does the program ask for valve timing at all. I had a breif look but didnt see them asking for it. I think its pretty important. All the issiues with exhuasts have me a little confused at the best of times. Dave Vizard doesnt seem to care a lot for custome exhuasts and has some evidence to back it up.( how to build HP vol 1). He is refering to 90 degree crank v8's only though. I tend to believe in Ed, Hytech, Burns and similar designers. I have seen 4 bangers make 15% more power with a good exhuast. Thats one thats designed properly against a custom not so well designed one, Not stock. I think that if you are going to the trouble of making headers they may as well be the best you can make. I also think that the reason your collecters are so long is that the program is designed to run without an exhuast. The whole length of the collecter wont be converging, a lot of it will be straight tube. Ed calls these collecter extensions. I will post the links of exhuast people that look like they know what they are doing tonight. Got to go to work now. Cheers, Douglas

P Is your primary pipe lenght cc is the volume of one cylinder in cubic centimeters The book may be expensive but I wouldnt do without it. Douglas

Joshua, The Headers by Ed info pack is really full of comparisons and Ed's opions but not really any hard facts on how to make headers. I think he wants you to spend more $ on his design service, then you get the real usfull info. The tape/cd is very usfull for putting small children to sleep on long car trips. I have book called " performance tuning in theory and practice" by A. Graham Bell. It has all sorts of formulas for finding the right size header for your aplication. His formulas are all based on exhuast valve opening before bdc. And then the rpm you want to tune the headers to. There is a table in the book so if figure out the opening before bdc I can look it up. When you have this info you can then figure out the size of pipe you need. ID=Square root cc/(p+3)*25 then *all by 2.1. CC is volume of 1 cylinder Hope that makes sence. There is a formula to do the tail pipe length and size as well and collecter size as well. If you want them let me know. Might be worth getting the book. Its been recently updated so some of the info may have changed from what I have here. Cheers, Douglas

Toyota is a good call, I was going to suggest over bored 18r pistons as the stroke is closer. It does have a hemi head though so probably wont work to well. Also have a look at pistons for the rover v8. I think the ones for the 4.0 engine will be close. I am surprised that the engine isnt based on the existing 4 cylinders like the L20. Douglas