z-ya

Let's both stop polluting what was a great thread. Thanks.

A little more static compression ratio to help off boost power? I posted this a few years ago, and would probably still use flat tops. I may choose a different cam. And I didn't mention what turbo I would use. It's the sum of the parts that matters. Consult your turbo guy before choosing a static compression ratio.

There was no disrespect intended. I guess I am tired of hearing about if you do this or that, you will get this, without any actual measurements to prove it. Again, no disrespect. People are quick to say "that's easy", or "it should work", when in fact to do it right is not easy. That was the reason for the "magic". I completely believe in measuring performance, making changes, and measuring again. I've probably dynoed my own, and other's cars more than most on this forum (and posted results too!). My last 13:1 race motor build was on the dyno three times (one engine, twice chassis). I've learned a whole lot building that motor. I'm just trying to share the knowledge. Here is the build thread if you are interested. http://forums.hybridz.org/index.php/topic/96584-road-race-enduro-l28-engine-build/

Do you have a problem here? I don't. If you can't reply in a respectful manner, then don't reply at all. I am only trying to help madkaw. And what you may think is obvious, was not obvious to me when I first learned it. Food for thought.

Any significant material taken off the head? Cam towers shimmed accordingly? 1.2mm is close to stock of 1.25mm, so the gasket shouldn't change the timing. Try the different holes in the stock sprocket to see if you can get closer to the cam card specs. You can also use the method I wrote above which doesn't use a degree wheel, but assumes that the cam has a symetrical lift profile.

I understand in theory what changing cam time could "potentially" do. Don't assume anything, especially when it comes to piston to valve clearance. Again, you need to start somewhere, so you might as well start where the cam manufacturer suggests. Just assuming that advancing it will make more power when you haven't measured the power straight up is a waste of time, and could cause catastrophic damage.

What head gasket are your using? What is the thickness of the head? These two items will effect cam timing. You should always time the cam "straight up", meaning exactly as the cam card states. Don't assume that by advancing or retarding the cam is going to make some HP magic. What pistons are you using? Flat tops with valve reliefs? Have you check piston to valve clearance? These are the things you need to be aware of when changing cam timing. You have to start somewhere, so start straight up.

For a stock motor, I wouldn't exceed 6500RPM. That is the correct tach. There is really no more power to be had above 5500RPM anyway in a stock configuration.

There is more than enough flow with the mufflers. Without them, you'd just have more ear damage.

Here are some pics of the exhaust off the car. The header collectors are 2.25", and the rest of it is 2.5". The mufflers are welded to the Patriot megaphones. The megaphones were cut on the small end to fit the muffler, and then slash cut at the rear perpendicular to the ground. The head and megaphones we ceramic coated by Sunkook River Powedercoating (Chris on this forum): http://www.srpowdercoating.com/. Three bolt flanges at the header, and single bolt slip on connections right before the mufflers. Minus the mufflers, this is how they ran them back in the day. Rearplugs are now required to drive the car.

Here is what the one that didn't break looked like on the car:

The ZCCJDM TC rods have two bolts connecting it to the control arm, but still rely on one bolt to tie the hockey stick to the rod: Same for Arizona Z: The TTT TC rods have the hockey stick welded to the rods: The only reason to use the hockey stick approach is so that the TC rod can be used with stock control arms. I don't think having one bolt holding it all together is a bad thing, as long as it can handle the load. The Arizona Z parts have been proven for years. The guy that made mine is going to increase the sized of the threaded Y bolt on the end of the TC rod to 5/8". He is also going to a bigger bolt that holds the TC rod to the control arm. He is also most likely going to change the design to one piece.

The guy to made these came by today and has decided to start from scratch and do a complete redesign. Here are some more pics:

OK, here is a video. Not moving, and the last time I'll start it this year. I'll get some on the track video next year.

Duplicate

We instruct at Audi and BMW HPDEs. Free track time, lunch, and 50min from my house. And yes, we are still sorting... We hope to do some races with VRG and SVRA next year.

I think there should be a gusset on the top and bottom of the control arm to minimize any flexing caused by the forces the sway bar exerts on it. I don't understand how just capping the end of the tube and welding it will prevent this joint from being the weak point.

The guy that designed them is coming over Saturday to look at everything. I think we are all in agreement, there are major flaws. He promised to make good, and firstly was concerned about the driver (which is of most importance). Stay tuned.

Yes, and like I said, I was looking for some new underwear. Not the first failure I have experienced on the track. I've also experience brake failure. Sluggish steering is a lot easier on the nerves than brake failure.

Exactly. The other side is bent up, and the TC rod end is also bent. Even if the tube was closed on the end, I still think it would have failed. I like the idea of a boxed design like the OEM ones. I'll post some close ups of the failure when I have them.

Very close. It broke at the yellow line. My guess is that sway bar pulling up, and pushing down on the control arm caused it to flex at the weakest point. It should be a boxed design like the OEM control arm. The Techno Toy Tuning arms are boxed, and a better design.

I had one of these fail on the race car this weekend (this is the 510 version, but the S30 version is the same design). The other was not far behind. I think I know why they failed. Let's see who can figure out how and why.

We will start another thread on the control arm failure. Yup, that's our local club site, and Skip took the photos. We will have more pics once we take it apart, but it appears to just be poor design. A local guy that makes similar control arms for 510s made these for us. I will not add my conclusion at this point, but I have a pretty good feeling what caused the failure. You really need to see what they look like to understand. When I get the picks I will start a new thread in the proper forum. In the mean time I needed some new underwear after that session We have been fighting handling issues this year too. The first two sessions the car handled OK, but still seemed really loose as compared to last year. On the last session when the control arm started to fail, it was turning OK to the left, but hardly at all to the right. Then it just broke. Good thing I was entering the chicane where there is a lot of runoff. And yes, the only thing holding it together was the sway bar and the TC rod.

Here is a pic from the event last weekend. Turn 3 at Loudon. Proof that it actually can do more than 1/2 half lap. They opened up the south oval (NASCAR) to the event for the first time. Oh, and after having control arm failure on the race car, I used my turbo car the second day: