bradyzq

Not that there's anything wrong with it, but it seems like you're trying to reinvent the wheel here. I understand that sometimes it can be a fun, frustrating, necessary step. Anyways, what are your goals, and what are you starting with? Block, head, pistons, turbo, engine management, etc. There is LOTS of info in the FAQs, and you will see that you can go very far with stock components.

Why would you want a 4 valve piston design on a 2 valve head? I'm sure it could "work" but would be far from ideal.

16 inchers for the back? If not, Coleman seems to have lots of customizable options for brakes. I mention them only because not many people seem to know about them.

Old thread here, but I thought I'd mention a trick that might extend the life of the solenoid. I suggest that you add or change the throttle axis to include a low TPS position at which the duty cycle is 0. That way, the solenoid won't always be needlessly energized while cruising, or even while cranking to start. The solenoid doesn't like being constantly energized. I think the max recommended duty cycle is 95%.

Sad to read this. I know stuff happens, but the shop should have reacted. If there was any doubt the RPM pickup might be causing an issue, then DUMP it! You don't need it anyways. I'm sure Dyno Dynamics have a sync tool for roller speed to engine RPM. Set it and forget it.

Lots of penetrating oil in the hole where the little lock bolt goes can help. Mine were rusted there. Also, I've read somewhere that they are designed to come out only in one direction. I don't know if I was trying to remove them in the correct direction, but in the end, the whole strut assembly had to come out and I used 13 tons of pressure in a large press to get them out. In the end, the only spot that had any corrosion was in the middle. My guess is that small amounts of water had entered through the locating bolt area.

Hopefully the dyno will have an air temp probe. I know my Dynapack does. It's the famous orange wire that increases power if you put it under the hood.;) (Dynapack tuner in-joke)

Gaaaa. Didn't mean to dredge up old (or not so old) wounds. You bring up a good point about batteries. As a chassis dyno tuner for the past 12 years, I can tell you I HATE lightweight race batteries. You can't boost them, they often safely charge at only 2 amps or less, and they're expensive and finicky. Weight savings don't matter on the dyno! For the dyno day, I suggest using a "real" car battery. I know in your case, everything runs, and there will not likely be much cranking away, but still....

I'm with TimZ here. Does not compute for me. Care to elaborate or point to your source? Intuitively, the air filter shouldn't care whether it's filtering 600hp worth of NA or forced induction airflow. If the filter were AFTER the turbo, then the volumetric flow would be lower for the forced induction setup.

And, I'm curious about the EMF issue. Did you happen to try to start the car with the water pump off, and then turn the pump on once the engine was running? If so, was the resulting intereference enough to cause issues? That whole issue seems VERY weird since the ECU shouldn't be firing coils until it knows the engine angle (passes missing teeth on the trigger wheel) and gets to the right angle to fire a pair of coils. On average, this would be a minimum of about 40 teeth counted including a valid missing teeth pair. Seems impossible for an electric water pump to generate an accidental waveform that perfect!! Are you sure the coils weren't being fired accidentally WITHOUT the ECU being involved?

LOL at "things always take longer than they do!" It's so true. Espeically when at the dyno, because you invariably spot something you hadn't thought of, and that can send your plan off the rails. Which is not always a bad thing. It may mean you discover and maybe fix an issue you previously didn't even know was there. So, to add to Leon's good advice, don't be disappointed if all doesn't go to plan (which I think you're already used to, based on the above!!). As long as you walk away with useful data, your dyno day should be considered at least a partial success. AAAAaaaannndddd, you mention that part throttle torque gains are your main goal. I strongly suggest that once you get the car to make clean pulls that you switch to ignition tuning. That's where your part throttle gains will come from. What do you have for measuring load on the Electromotive, TPS or MAP?

Looking good. One way to check if your cam is stock is to measure from the tip of the lobe across to the bottom of the base circle then subtract the diameter across the base circle alone. My guess is that the cam is not stock, based on the n42 head and flattops you've already discovered. I'm sure someone can pipe up with stock base circle and cam lift numbers for an n42 or l26 e88. Your seats are awesome, but for track duty, these days having a provision for a HANS device is becoming a no brainer. Second set of seats, maybe?

Have you checked to see whether your electric fuel pump is working? The symptoms sound like perhaps your mechanical pump is drawing through a failing or failed electric fuel pump, and with only limited success.

Small dowel pins also work for locating the intake on the head. Sounds/looks like a great job was done. Enjoy your newfound flow and det resistance.

Nice! It looks like you're moving away from "please don't blow up or self-machine" to "let's make some power!" I don't have Z experience on this, but in other setups, mainly VW 16V, ITBs give only losses until high RPM, when compared to a plenum with single throttle. Also, both low and high cam profiles were designed with VVT in mind, which you currently don't have. For the street, a single TB, VVT, and a milder cam profile might be the hot ticket, though admittedly more boring.

You're effectively running the Honda K20A2 VTEC cam profile, right? Not the low RPM profile? I would expect a huge high RPM bias. And in my experience with ITBs, they rarely show gains over a single throttle intake until high RPM with big cams. They sure look and sound good though!

Heat soak? Vapour lock?

Audi (and probably others) are dumping boost like this on their 3.0 supercharged V6. It's a blower car that can actually increase boost with only a chip. No need for a pulley change. The EFR line of turbos come with a shaft speed sensor flange cast in, among other goodies. I'd love to try tuning a car with closed loop turbo shaft speed control. Re: cam control, yes PWM for sure, but PID needed as well, since they tend to have a "hold" DC. Any significant change in DC will rail the cam to min or max retard. Not that I'm a likely customer for one of your heads without a windfall, but DOOOOO EEET!! (VVT, that is.) Or make it doable for those who want to. Even having just a 2 position cam timing switchover can make a big difference in torqueband. /end enabling

Many manufacturers offer something similar. Might a Toyota piece be easier to adapt?

IME, traditional VTEC (switching cam profiles) has acted best as a torque extender. There may not be that much of it, but it keeps on pulling, giving Hondas their typical flat wide torque curves when tuned correctly. In the Datsunworks head, it seems not to be practical. However, having just variable valve timing on the intake cam only can make quite a difference in torque curve width too. The cams would be the same, with perhaps the exception of the nose of the intake cam. You'd "just" have to make space and oil lines for an oil control valve and the infinitely variable cam sprocket, and trigger wheel, and sensor.

Very interesting stuff! A question I don't see answered is when to unbolt the prebent head from the block after welding. Right away? After a certain specific cooling period? It seems counterintuitive to wait until the head has cooled fully.

TimZ: Yes, I was referring to a single tooth on the cam only to sync which 360, not 6 teeth on which to trigger spark events. 6 teeth would be a huge step backwards indeed! FricFrac and TimZ:You don't need a twin post coil to run wasted spark. You can use 6 COP or CnearP coils and fire them in pairs. You can even use 6 coil drivers instead of 3, if the coils don't have them built in.GM LS style coils come with built-in ignitors and will still be loafing (40% duty cycle or so assuming 2.5ms dwell) along at 9000RPM in wasted spark. If you need extra dwell for boost at 9000RPM, well, you're in the 1%, and if you can't figure out a way to get a cam sync trigger (VR or Hall is what pretty much all the OEM use) in there, you probably shouldn't be building a 9000RPM turbo twincam Z!

Actually,sequential spark is NOT more precise, nor does it necessarily provide a hotter spark than a wasted spark setup using only a crank trigger wheel like Derek offers in his EDIS kit. Such a setup will be MORE precise than any setup run off a cam or distributor mounted trigger wheel. As Derek implied, EDIS is not the best way anymore, but the trigger and sensor themselves are still current. Maybe a 60 tooth wheel instead of 36, but that's it. A single tooth cam trigger can be run directly off a cam lobe, or any bump up there. There are threaded sensors out there that would require only drilling and tapping, admittedly precisely, the valve cover once. Presto, full sequential everything! But in the meantime, among just the products Derek offers, you can achieve the highest timing precision possible. You'll just be achieving it twice per cycle!

I don't know if this is applicable to you, but beware of crushing the head slightly due to using the too small washers ARP supplies with some of their head stud kits. This is known to happen on some older Audi heads, where you can end up with a washer sized dimple around each stud.

Old Audi 5000's (and 4000's, Coupes, and urQs) had Bosch CIS mechanical fuel injection, with normal distributors and plug wires. You must be thinking of the braided fuel hoses to each cylinder and the fuel distributor/metering head they came out of.