XTCoX

Thats what I like to call "hitting the nail on the head". I've actually been party to the scavenging, he took some parts off me in the course of doing buisiness with him. My bad, everybody. At least I won't forget to do my homework next time hahaha good lord! There's a novel of bad press out there on him. I should've known something was wrong when I called him asking for the valve adjustment spec, and he gave me different values from what Schneider recommends for the grind. I even asked him why and he said, quote "that's just how I've always done it". No reason or anything. I had to email Schneider to get a reason for using one spec over the other. It was a single sentence reply: .010/.012 better mid torque, .008/.010 runs better and opens the top end. Al was convinced .010/.012 was better, and the other would harm the engine, or something... He even asked why I was bothering to adjust the valves, because I guess he did it before he gave it back to me, and valves aren't supposed to move once you set them (he said sarcastically). Funny, considering when I pulled the valve cover to check them, they were all out of spec. Only two valves (on different cylinders, I might add) were close. Fail. It would be worth my time to get the legal gears moving, provided I can make a case that it was a bad rebuild... I feel like it wouldn't work considering I messed with the timing, which would throw into doubt who messed up and when.. I can say, however, for anyone else out there, that I haven't been satisfied with any of the business Ive done with Datsun Parts LLC. Though I'm too embarrassed to say exactly how much, I'll say that each and every part I've gotten from him has had something go wrong.... Believe me, I wish that were an exaggeration, but it's not. I had to return two separate heads to him for leaks, and now my block is on the fritz. Not to mention abysmal customer service. He was always irritated and impatient when I spoke with him... If you're looking for support after you finish your transaction, get it in writing.

FYI the engine was built by R Rated motorsports, through Datsun Parts LLC. While I can't speak to the quality of the rebuild, I can share a story. When I called Al, and told him the timing wasn't set (knock) and the valves were really loud he basically wrote me off like I was just hearing things/stupid. He seemed to be feeling a strange combination of surprise and irritation when I told him I was gonna work on it. So I adjusted the valves and backed off timing until it wouldn't knock. Sure enough, it nearly throws a rod two weeks later cause of the subtle detonation I was apparently confusing for standard engine noise, at which point he kindly pointed me to the 30 day warranty, and told me it's my problem. Of course we did only pay for an engine. Tuning wasn't included. What did I learn..? > Now, I don't know how long engine rebuild warranties typically last, but 30 days seems sketchy for a part that should go 100k miles with no problems... But again, I have no idea what's typical. Guess that's what happens when you don't think things through the whole way though... I got what I paid for.

I had selected the parts individually and had the shop assemble it, so everything is confirmed. The detonation would sound like loose change in the engine. I just took it for a second opinion at an import specialty shop, to diagnose that sound in the depths of the engine? They said I'm about to spin a main, and that it might have been the detonation that did it. Fack. The sound comes and goes at different rpms and varies with load, but is undoubtedly getting worse. In order to verify all the timing (cam, pulley mark) I'm gonna have to pull the head and take a look right?

I have checked the static timing with a light, it's basically on top of TDC ad idle but I have not used it to check full advance. Good idea I'll get on that. I am also unfamiliar with how a load controlled ignition works, but I'm guessing it's for going up hills? Correct me if I'm wrong, but isn't the vacuum advance supposed to do that to some extent? And the engine isn't stock, that's the thing... Full 6-2-1 exhaust, flat tops, and the power band of the cam is supposed to be 4-7k, for road racing. It's very frustrating considering the engine isn't stock but I'm still having those stock issues. If by stock you mean there has been no actual modification of the head then yes. I'm feeling that the cam profile was too aggressive for an unmodified n42. I will check the cylinder pressures and get back to you. If it is over 200, do I retime the cam or get a bigger gasket?

Thanks very much for the insight It makes me feel better knowing it's not just supposed to be 'bolt on and go' with that high rpm performance, I thought I was doing something wrong! Haha Looks like once I sort out the timing bug, I'm giving BRAAP a call about headwork! In regard to your shiny ignition system the main advantage over a CD distributor system is the advance curve control yes?

Oops, just saw your signature with your engine specs. Think the carbs might have something to do with this problem? I've seen SUs pull hard through the rpm range, but could the top end bogging have something to do with using needles that aren't perfectly identical? Could I be causing a harmonic imbalance between the cylinder banks?

Thanks for the quick replies! I had heard the advance curve on the Unilite was adjustable, so I'll give that a shot (: gotta look up the process though, I haven't recurved a distributor before. Thanks for the quick math Lazeum haha Also, Lazeum, what head and timing management did you switch to? Like a shaved p90 or p79? (But with the p90, I couldn't boost it until I had forged pistons and a CR of like 8:1 right?) Madkaw no I didn't degree the cam, the shop did. Also one of the problems I had on the list considering it's not behaving up top.

Hi all, new to the communinty, I had a few questions regarding why I cant seem to run more than about 2 degrees advance at idle without getting detonation. First the basics, its an L28 with flat +1mm pistons, N42 head, 1mm headgasket. 290F schnieder, .495L/.290D. Crane Hi-6 CD system, LX92 coil Mallory Unilite, which has 24 degrees mech. adv @ 3k 91 Octane. SU carb with some modded SM needles, tuned with a wideband for 12:1 at WOT and just rich of 14.7:1 everywhere else. I got close but its not ideal. Searching for needles atm. Im pretty sure it has something to do with the fact im running 91 in a 10.1:1 cylinder. But im in socal so the easy fix of buy better gas isnt an option. Got any cheap addive recommendations that wont eat my fuel system? The reason im even calling it a problem? The damn thing WILL NOT PULL past ~5500rpm. It will hit the limiter I have at 7k... begrudgingly. Its super happy and pulls really well up to 5k, but refuses to continue on up in the same way despite a nearly dead on 12-1 afr.... was I right in looking at timing next? Even with the timing almost on top of TDC it knocks from time to time, but ever so slightly and under full vacuum (partial throttle) below 3.5k. Gotta be kinda hot too. Any help is greatly appreciated. The engine was just rebuilt by a shop that I probably shouldnt mention right now considering the other can of worms I think I have with a potential rod knock less than 4k miles into the rebuild. Not to mention they didnt time the thing before they gave it back, AND, when I pulled the valve cover off to address the metallic, intermittent knock coming from within the bowels of the engine by doing a valve adjustment (kinda silly, I know), I find the valves are all out of whack. As in a couple thousandths difference beween almost each of the 12 valves o.0 All it did was shut the valves up so I could hear the knock better.... Thanks in advance all

I would check the float levels in the carbs. recently I spoke with Bruce over at Z Therapy about a lean surge I was getting through the upper rpm range (A less severe version of this 'wall' maybe). Anyway, I adjusted the float level up, which pepped up the car and allows it to climb higher up without choking. You would probably want to consider replacing the Jets on the inside of the float bowls as well, and check the nozzles to make sure they aren't clogged. Let me guess, when you say it hits the power wall, it's like half the engine shuts off?

I know that for my situation, weight is an area of huge concern. So, the SR is what's lookin good to me right now, but I know that when you get up in the 400bhp range (where I wanna be) when the boost comes on, its pretty harsh. And because I need to daily drive it, I dont know if thats what I want.... course, I could just get one of those 2-stage boost controllers... Anyway, from what I know from racing, low weight (even at the cost of peak HP) is much more beneficial to actually "going fast". Turns are quicker, there's less weight to throw around and upset the suspension, and if you dont lose speed easily, you dont have to get it back with 800hp.... 3-400hp is plenty for moving a light car. IMO the smaller, lighter engines are more effective for low track times. But if drag racing is your thing, then i'd just go balls-to-the-wall and cram a 2JZ in there.

Sorry, double post

So, Timbo, how much heavier is this engine than the L28? Ive been considering doing this, but Im not going drag racing, Im doing Willow Springs and Auto-X, so do you know if this thing (with the turbo and the I/C) throws off the handling too much? Have you had it corner balanced or weighed yet?

Well my understanding is pretty much the same as yours, which is why Im so stumped... My only possible explanation for this is that im still running the old 240z stock air cleaner, which, (with the mixture richer) could be restricting air flow. However this is a weak explanation and I doubt its right, but its all Ive got. Im probably going to try an and lean it out more to see what happens, but that stupid knock is going to seriously get in the way of my tuning...

How do you know its 8.5:1? A stock 240 has a 9:1 CR, and my engine has the .290 duration cam in it, and the 280z valves... Wouldn't that be closer to like 9:1 or 10:1?

Not a clue. But thats an intense ignition system, all custom I take it?