Nigel

I datalogged both on my Z, using a Hallman MBC, and I can clearly see boost spikes with the wastegate signal from the manifold. With the wastegate signal from the turbo, it hits the set boost and holds it nice and steady. Nigel '73 240ZT

I don't get why so many people are having problems. My shafts go in with no problems. In addition to flipping the outer cage, I too ground a bit of the end of the shaft leaving about 1/8" before the snap ring groove. But even without grinding the shaft, I think they'd still go in. And I am using the dust caps on the end of the joint. Mind you, my adapters were custom made by a friend of mine, who machined off the old flange and pressed, welded and pinned a new CNC'd flange on. But I can't imagine that the overall dimensions of the MM adapters are that much different. Strange... Nigel '73 240ZT

That's a pretty good idea actually. So long as they don't weld the T3 side to the manifold! Nigel '73 240ZT

http://en.wikipedia.org/wiki/Dieseling Nigel '73 240ZT

There should be snap rings on both ends of that bearing race to locate it on the shaft. It's not meant to slide on the shaft in either direction. NOTE: I just noticed that this is for a Q45. I don't know if that makes a difference... Nigel '73 240ZT

You can run the steel forks from the 4 speed. That's what I had in my old '82 ZX 5 speed. All you have to do is drill out the roll pin hole for the larger diameter pin used in the aluminum forks. I also used the steel front cover from the 4 speed as well. I've heard of the aluminum ones breaking (although, that's probably due to something binding in the clutch mechanism). Nigel

I was able to extend the plunger on our dial gauge at work, and get it down the #1 spark plug hole. As best I could measure, it looks like the pulley mark is only off by 3 degrees, or a bit more. That could be the manufacturing tolerance. I've bumped up my base timing by 5 deg across the board, so I'll leave it at that for now. I need to get a timing light on it to see if I set the SDS timing right to begin with. It was 7 years ago that I first did it, and I've never double checked it since. I just need to find the time to visit a buddy with a timing light... Nigel

The 240SX transmission also uses double roll pins... Nigel '73 240ZT

I'm not trying to be mean here, but you really should take the time to understand what these parts do before you start messing with them, especially when it comes to brakes. First of all, those two parts you gutted are not both proportioning valves. Only the one on the firewall is. The one on the shock tower is a brake pressure warning switch that warns you if there is a pressure loss to the front or rear brakes. So, by gutting it, you've just disabled that safety feature. Secondly, by gutting both, you've effectively tied the front and rear brakes lines together at two points (nether should be), bypassing another safety feature. The front and rear lines are kept separate so that a failure at one end will still allow you to have brakes at the other. You need to reassemble the warning switch and as for the proportioning valve (on the firewall), it should be removed and the gap in the lines should be spliced together. The proportioning valve uses pressure to the front right caliper to regulate pressure to the rear brakes lines, so that's how you tied the lines together there. This may not necessarily explain your spongy pedal, but you should definitely address these mistakes first. Nigel '73 240ZT

I don't believe anybody on this site sells the actual flares (with the exception of the group buy for the extra wide version). You need to talk with a company like Motorsport Auto (see link below). Or, if you search on line, you should be able to find some other vendors. http://www.thezstore.com/page/TZS/CTGY/7BSA02 Nigel '73 240ZT

You've never seen a base model Civic with a wing on it that's so big it wouldn't look out of place on an actual airplane? Nigel '73 240ZT

That looks like a CS130, which was a replacement for the 12si. It was used in the early '90s, and then was upgraded to the CS130D. Not as powerful as the CS144, but definitely a step up from the 12SI... Nigel

Compression ratio is a function of cylinder volume, not cylinder pressure. Pressure is affected by cam timing and the temperature of the gas, which goes up as it's compressed. Pressure at TDC is typically 15 to 20 times that at BDC. Nigel '73 240ZT

True enough... I just don't like the idea of forcing something to bend to accommodate a misalignment, like the upper bracket is being made to do in this situation. Still a great idea though, and as we agree, a few washers will solve any alignment issues... Nigel

Yikes! It looks like it cracked and then was welded, only to crack again. And it looks like the weld was ground or filed down, not turned on a lathe. No way on earth would I put that on my engine! No sense risking crank damage... BTW, it's either dampENer or damper. A case can be made for either, but dampNer is a spelling mistake as best as I can tell. Nigel '73 240ZT

Question... This is a great, cost effective solution, but are you sure the two mounting points are on the same plane? When I put a straight edge from the timing cover, it looked like the upper alternator mounting tab on my 12si was ~1/4" forward. It could be that the CS144 alternator is different, but did you check this first? I'd want to make sure before tightening everything down, otherwise you could end up with broken mounts at some point in the future, or rapid belt wear. If it is out of alignment, it's easy enough to fix with a spacer (for example, a few washers). Nigel '73 240ZT

Well, I just tried moving the pulley by hand, and it won't budge. However, I can only get at it with one hand, due to the electric rad fan and intercooler plumbing, and I can't get much of a grip on it. So, I'll have to label this test as inconclusive. I think the only way I'll be able to tell for sure is to set the engine at TDC... Nigel '73 240ZT

Thanks Tony! I'll give that a try. I ordered some replacement magnets from SDS last night just to be safe. I know where I can get a new Euro pulley locally, but cash is pretty tight right now, so I may end up just getting another used North American one. Fortunately, I kept my magnet template from when I first did the install... Nigel '73 240ZT

Well, I thought about checking the timing, but I don't think that will tell me anything. The timing mark and the trigger magnets are on the same pulley, so the timing will probably look correct. Unfortunately, my timing light is at my father's place 250 miles away, so I can't verify that. The only way that I can think of to know for sure if the pulley has slipped is to set the engine at TDC and see if the timing mark on the pulley matches the 0 deg mark on the timing indicator. But there's no really simple way I could find to do that. I was going to see if I could get a rough idea of where TDC is by putting a rod through the #1 spark plug hole and trying to find the point where it sticks out the most. I realize there are a few deg of crank rotation where the rod won't move, but if the 0 deg mark is significantly off that should tell me what I need to know. As for my timing curve, I was starting with 20 deg at idle, and ramping up to 38 deg by 2750 rpm. AFR's crusing at 75mph are low 15's. I do remember my mileage being much better than even the 24 mpg I got last year, but I don't have any records prior to last year. The engine feels great otherwise, so I'm not sure why it's so bad now... Nigel

Sorry, I should have clarified that I'm talking about the rubber damped pulley slipping on the harmonic balancer hub... Nigel

So, I'm aware that a slipping harmonic balancer pulley can be an issue, and I'm pretty sure my pulley has slipped. But I wanted to get some other opinions on the symptoms I'm seeing. I'm running an L28 Turbo in my 240Z with the original L24 pulley that came with the car. I have an SDS EM3-6F system with the trigger magnets mounted in the rubber damped part of the balancer. What I have noticed: 1. Fuel economy seems down. I haven't done better than 21 mpg on the highway this year, but I have a receipts from last year with one indicating a best of 24mpg (mind you, I'm running a 240SX 5 speed this year, with a slightly shorter 5th than the '82 280ZX box it replaced). 2. Full throttle acceleration feels a little flat. 3. Two or three times when starting the engine, I've heard a very brief chirp, kind of like a slipping belt. But the belt appears to be tight (takes some effort to twist it 90 degrees) 4. The idle timing has always been set to 20 deg advance, but I've noticed that idle speed and smoothness significantly improve when I crank the timing up to ~28 deg or more advance. 5. I bumped up all the timing values by 10 deg and acceleration seems crisper, and EGT's cruising on the highway have dropped by at least 50F. Fuel economy hasn't improved though. I realize that the best way to determine if the pulley has slipped is to set the engine at TDC and check the timing mark, but I'm not sure how quickly I'll be able to get around to doing this (is there a quick and dirty method I can use?), and I don't want to delay getting the necessary components together to replace the balancer. The most telling evidence appears to be that I can run 28 deg or more advance at idle, and the engine actually runs smoother. I cranked it up as high as 40 deg advance at idle and much to my surprise, it didn't seem to make much difference. I would have thought that there would be a point where it starts to run noticeably rough again. Regardless, I've never tried cranking up the idle advance before, so for all I know, this could be normal. In the mean time, I've painted alignment marks on the balancer so I can see if the pulley does indeed slip at some point in the future. Any insight would be greatly appreciated! Nigel '73 240ZT

I also want to confirm that using masking tape to hold the weatherstripping in place as you put it on the glass really helps. And, after you get the weatherstripping on the glass, put the trim in before you install the glass in the car. It is so much easier than trying to do it with the glass installed. Again, just use tape to hold it in place until you're done. Nigel '73 240ZT

Do you mean as a pre-filter for the efi pump? I think if you're getting your feed for the high pressure pump from the bottom of the filter housing, the fuel isn't filtered yet. I don't recall where, but I have definitely read of people having issues with the return fuel heating up the surge tank. I don't see why you couldn't run the return line direct to the tank, and have the overflow line from the surge tank tee into that. If you match the flow rate from the low pressure pump to that of the high pressure pump, then I don't think you should have to worry about the surge tank running dry. Nigel '73 240ZT

The goldenrod filters with the plastic tanks look like they could fit an internal pump into them. But they have a metal cap which would make the electrical connections more complicated... Nigel '73 240ZT

6400Hz to be exact. I just read a great article on this very subject: http://www.clubwrx.net/forums/tuning-electronic-engine-management/14426-engine-basics-detonation-pre-ignition.html To summarize, detonation does crack ring lands, but it's Pre-Ignition that actually blows holes in pistons. Prolonged detonation can lead to, but is not necessary for pre-ignition. Pre-ignition is caused by hot spots that start the combustion process long before the spark plug even fires, which results in the piston trying to compress the expanding, burning (not exploding) mixture. Consequently, it is undetectable by a knock sensor. Detonation is a spontaneous explosion of the mixture AFTER spark ignition has occurred usually at the point furthest from where ignition was started. It causes a rapid pressure spike (apparently NOT due to the flame fronts colliding) that resonates in the block at 6400Hz and can be detected by a knock sensor. The longer it takes the mixture to burn (the more advance required), the more likely detonation will occur. Consequently, combustion chamber designs that result in the shortest burn time (least advance required), are the least detonation prone. Interestingly, the coveted "HEMI" engine is apparently a poor design, requiring excessive advance making it prone to detonation... Nigel '73 240ZT