Xnke

They *think*...are those rocker arms resurfaced on both the lash pad surface AND the cam lobe surface?? New cam, resurface the cam-lobe surface...lash pads that are cut without the side reliefs need resurfaced lash-pad faces. Yeah, the 280* cams sound pretty nice, and the one I have idles best at about 900RPM.

Cams for engines of larger displacements are often times smaller profiles than the same engine of lesser displacement....the L is not an exception... That said, check the cam stamps. the K stamp cam is ~.400" lift, 218 degrees duration, and the A stamp cam is about .410" lift, 248* duration.

Yes, I've done some oxyfuel welding of aluminum. My advice is don't even pick it up to try, unless you are making airplane fairings or full aluminum bodies. To do it right, you'll have the same amount of money in the setup as buying a 200A AC/DC TIG with pulse function. (I paid about 700$ for mine plus the first tank of gas and 3lbs of aluminum rod) On top of that, you need special lenses in the helmet, you need a full-face mask, goggles won't cut it, and you need a flux to strip the oxides, very similar to brazing flux. Also, you won't be doing thick-to-thin that way, without a LOT of practice. Oxyfuel welding of aluminum is mostly used for doing large sheet forming of aluminum that will be finish-formed on an english wheel or with a hammer and dolly; as the weld deposit is more ductile. Fabrication work is expensive...it requires expensive (money) tools, expensive (time) training/practice, and time for a fabricator to work out all the details in the plan, cut the parts out to the marked dimensions, correct the marked dimensions to ones that fit correctly, apply his expensive tools and expensive training into assembling/welding/fitting/machining your project into existence. It's called Spending Time for a reason...your fabricator is investing *his* time into *your* project, based on receiving currency return. His time, experience, training, and tooling cost him, and he has to recoup that cost by charging for his time, pay for his training, pay for his tooling, consumables, ect. In short, You either pay someone to do it, or you invest the time, tooling, training, and recoup your initial project plus a new skillset.

well dang I just lost a huge edit to that post, and I am not prepared to re-type it.

Yes, the R200 differential is strong enough.

It's going to be expensive. The parts are cheap, but the *time* it will take to get them fitted properly is what you are paying for. Price the time at 2$ an hour and you might find a price you like... I'd offer to do the job, but it would be 800-1200$ plus materials, so there's no point.

As I said in your other thread, you will need to adjust the valves several times in the first few thousand miles...and they will get tighter before they get looser. If you can't get the cold lash on a new head, you're stuck. I think I adjusted mine every thousand miles for the first 12-14K, and they were tight every time. the last two valve adjustments have come out clean, no adjustment needed, so I think I may have reached the "level" spot in the valvetrain life curve. I'll probably be a few thou tight next oil change, since it's been two oil changes now and they haven't moved.

NewZed, the cams are probably the same...it's the rocker arms that changed. I have some here that are either ground funny or are made different...the same M stamp P90 cam measures out .390" to .393" with 5 sets of 12 arms, then I have two sets (from earlier engines, no less...one came from a 1970 and one from a 1972...all the rest of my rockers are 78-84) that with the same cam, in the same head, with the same valvetrain, show lift numbers of .384" to .385". I can't find any consistant indicator though, the only reason I know they all came from the same engines is that I kept them all on a string through the hole in the rocker post cup, and labelled. These are all the 2-piece arms, I don't have any of the real early single-piece forgings.

If you are buying the MS1 kit, borrow a stim from someone, unless you are very experienced with electronic kit construction. MS1 Extra (the extra code does spark too) will easily do an L28ET at 14lbs, no problem. Do you have the 81 turbo crank sensor, or the 82-83 turbo distributor? The turbo dizzy is well documented here, but the 81 crank sensor can be used too, if you are willing to spend the time with a file to go through and edit the tooth count on the wheel. Using the crank sensor type system is rather undocumented, but if you have the patience then yes, it can be done. Might mean making a new trigger wheel from sheet steel. Get the MS1 3.0 kit. The 2.2 kit is cheaper, but it is more susceptible to electrical noise, and an MS reset at 14lbs boost is NOT going to be a pretty thing. You definitely don't need the MS2 or MS3 kit unless you just want the extra features, MS1 with the Extra code installed can handle 80% of the L28et's out there.

Using the Autotune feature is pretty easy; but you need to make sure your injector dead time is spot on, you have your voltage adjustments correct, and that you have your AFR tables exactly the way you want them. The delay stuff is not terribly important for the first few passes of autotune, but as you get more data on paper you do need to check them to see if they need revising. Also, once you have the above settings locked in at the best you can get, the autotune feature is AWESOME for tuning spark map. Tell it not to update the controller, and adjust your timing in the area of interest...then let the autotune run and show you what kind of difference it made to AFR...it also shows up in the Delay settings, and MAPdot traces. You can simulate a LOT of fancy equipment with the datalogging, but the Autotune stuff shows it in such a visual manner that it really clicked for me.

Any lash pad thicker than 0.120" is usually a flat-bottom lash pad. That's completely normal. Does the tapping sound track crank speed, cam speed, or valve speed?

I have a factory-style 3-row 240Z radiator in my car...it had the brass-brazed fan guard on the upper tank, and has three rows of tubes in vertical downflow. It's 2 1/4" thick, and I need something about 1 3/4", ideally, to clear the new belt drive for the supercharger. Like some other people in this thread, I have serious undercooling problems when the temps are 40F or lower outside, the car struggles to get to thermostat-opening temperature, and it will never reach that temp in normal driving if I have the heater on. I'm lucky to see 140F water temps on a 32F day. Anyone got a measurement on the thickness of the 2-row radiators? Or the 1986 Camero radiator that the JTR kit suggests?

Swapping any Nissan JECS, ECCS, or NAPS ecu into any car requires 4 wires to be hooked up, if you have the engine harness and ECU to match the engine... I have never, and will never understand the fear of wiring harnesses. That said....Why would you ever want to go to a 4-cylinder over an equal displacement six?? Especially when the six will come out less costly in the end, and have a better upgrade path. RB20, once installed, can easily be swapped for RB25, wheras you're stuck with the SR20 when you're done with that swap.

The headgaskets are Not the same. Use the headgasket that matches the block.

I do have to agree, that is a sweet looking setup. I really like that fuel rail look. I fully understand the "This is the way I'm going to do it, because it looks awesome and it's my car" thing, that's 85% of the reason I have the intake I have now, and the one on the bench. Same with Derek, and his Trumpets, they're just flat cool.

Look at the runners between 1-2 and 5-6 on the SU manifolds...there isn't length before they merge into a single runner, so this is the theorized order of events: 1 draws full charge, being directly in line with the carb, 5 draws charge stealing a little from 6, 3 draws charge, 6 draws a full charge, being directly in line with the carb, 2 draws charge stealing from 1, 4 draws charge. If you have the SU's OR the port fueling manifold conversion like Z-ya and I are running, tuned such that 1, 3, 4, 6 are all at stoich, 2 and 5 will be a little rich. Tune for 2 and 5 at stoich, and 1,3,4,6 will be a little lean. It happens on the port fueling manifolds due to the same charge robbing, the vapor floating near the port gets drawn BACK up the manifold, then back into the adjacent port. With a stockish cam, or a cam setup to minimize low-speed reversion, then this is not so much a problem, but even stock engines with SU's show this if you check the plug colours. Longer runners reduce this tendency, by making the airflow have to reverse along a longer path, which is doesn't really want to do if it isn't easy. I *think* that this is why this happens. I could be wrong, but I'm not the only person who has noticed this issue with the carb manifolds.

A simple flip of the angle gauge means that the injectors don't miss the port walls as I intended, but instead impinge on the port floor, about middle of the short turn radius, biased to the side closest to the adjacent exhaust port. Lucky mistake, I guess. The view down the injector ports shows the port floor to intersect the flow path about centerline, and then what misses the floor would be hitting the back of the intake valve. We'll see how it works. The GM TPS might be useful for a VW too, I think the EFI throttles use the same 8mm D shaft? In any case, the Cavalier unit is much more compact than the comparable Nissan or Bosch units. It's also got an O-ring seal, to keep water out of the potentiometer housing, so no more wet TPS problems. (I still don't see it as a real problem, unless you're powerwashing your engine or something.) I'm pondering having the finished product powder coated satin black, but I'm worried about how well the powdercoat will adhere to the aluminum. I think at a minimum a phosphoric acid etch would be required, but I'll have to do some research.

So I got the counterbore made this evening, hardened and sharpened up. It's an old-style D-bit reamer, with a pilot on it. I use these things all the time in my gunsmithing stuff. Got the injector bungs counterbored and test-fitted the lower injector seals. More on the TPS sensor this weekend, when I get it fitted up.

It's actually the lowest valve lift of any of the cams I've measured. The P90 hydro cam (M stamp) I have in my bedroom works out to be .390" valve lift, including the rocker ratio of 1.48.

I have found a TPS! The unit from a 2002 Chevy Cavalier will fit the D-shaft output, rotates the correct direction, and has a common, weatherproof connector. And it's 32$ for a new one. It is clocked nearly 180* from the nissan unit, but not quite. I will have to make an adaptor/spacer plate to fit it but it should serve the purpose quite nicely.

Really, using the 4bbl manifold and TBI isn't going to gain you *much* more than a "perfectly" setup carb would...that is, you would be dealing with the same issues of charge robbing and unequal runner length. You'd gain better precision control over the fueling, and easier precision tuning over a carb, but other than that it'd be pretty equal to a well setup carburator, especially at WOT. Part throttle economy will be better with TBI, though, as would drivability. The killer on any straight six with a 4bbl, is going to be cylinder distribution. So far, I've not seen a way to mount one carb in the middle of six runners, and get around that issue. The closest an OEM has gotten was the Slant-6 Hyper-pak, which has LONG runners, trying to minimize the differences in length. Even the SU carb manifold has distribution issues, on runners 2 and 5, in some applications.

You could have the incorrect oil filter installed. You need to make sure it's an anti-drainback filter, and if it is, then make sure the anti-drainback valve isn't broken....not sure how to check that except put on a new filter and see if it goes away. What's happening is that the oil is draining back down out of the cylinder head, and on initial startup the oil galley up to the head has to refill, and one or some of the lifters have bled down. Once the oil pressure comes up, the noise goes away. Also, might be time to check your oil pump, and check your lifters individually to see if any of them are sticking. But what you've described sounds like lifter slap, acts like lifter slap, and could probably be cured, by treating it as lifter slap. It's a duck.

Not that I am aware of. You could rework the bracket to run on the A/C pulley and unbolt the front stamped steel pulley from the damper though, wouldn't be terribly difficult.

If you want to be unique, the ford Taunus V4 is out there too...

Are you running stock flat-tops, stock rods, and stock crankshaft? If so, you should not be having a problem, UNLESS you had the block decked. If you did, then the thicker gasket might help, if you didn't and the crank-centerline-to-deck-surface isn't 207.85mm, then someone else did. 207.85mm is the "factory" distance, from crank centerline to top of deck (IIRC...could be oil-pan rail to deck, but I don't think it is)