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Yes, I'll agree with that!!!

Thanks for the links Stepan! Food for thought from the Klinkman too!! Cheers guys. I'll be looking locally for switches. The prices aren't too bad from summit, but the postage and packaging costs they charge are outa control. Pool and spa centres have switches that are suitable for this sort of thing from what I can remember reading in Autospeed. I'll go there and hunt around. I'll let you know how I get on. Thanks.

The situation with the brake booster is this. There should be a valve in the brake vacuum hose line between the manifold and booster. This is a one way valve, that way your brake booster never sees boost, only engine vacuum. It's assumed that when you've got ya foot on the brake, you've got ya foot off the gas (no boost). Cheers.

I've read somewhere that the LD28 diesel rods are too big and heavy to use in a petrol engine. Did you have to modify (lighten) them or are they OK as they are? Do you know what's the small end pin diameter is on the LD28 rods? Cheers.

I've done some work and came up with the idea to use a 'tap' or water cock/valve to stop or regulate the flow of coolant through the intake manifold. I could've bypassed the manifold completely, with no coolant running through the manifold at all. However, I wanted the option to use the heated manifold for warmup during the cooler winter months (A problem with previous setups when I didn't hook up the coolant through the intake). Today I started my engine and let it warm up to the point of thermostat opening. I was able to touch the base of the manifold with my hand without it being really hot like the radiator and radiator hoses. This was with the valve shut. When I opened the valve to let the coolant flow, the temperature of the manifold increased quickly to match the temp. of the rest of the cooling system. I could get tricky here, and setup some kind of thermostat arrangement, coolant through the manifold to speed warmup, then shut when engine is warmed up sufficiently. That might be overcomplicating things...maybe? The potential problem I can see with this is to accidentally leave the water valve open and advance the timing to where the engine makes best power. Ping city! Hmmmm, how to have the best of both worlds........ automatically? Ideas? When I get the chance for better weather, I'll take my machine for a run and play around with the ignition timing. The E32 was only 3km/h slower on the 400 meter run (G Tech) compared to the Arizona manifold when last tested, and that's with 10 degrees less static timing. I can't wait!

For my project, I decided I wanted a better rod to stroke ratio for my L28 turbo. I'm using a stock L28 crank, custom 136.5 mm rods and JE forged VG30DETT pistons which have a pin height of 31.8mm's. This works out to a rod/stroke ratio of 1.73 for that combination in an L28. Significantly better than the stock 1.64, IMO.

One type of L20A crank has a smaller big end journal (45mm's), like the L24E Maxima's. The larger L20A crank is 50mm's like the rest of the L series family. I wonder how many rods you could find/use on the smaller L20A crank? Hmmmm.....

No, there isnt a heat shield under there. Unlike the EFI and the SU manifolds, there are no cast in bosses that allow for a factory fitment of one. Doesn't mean one can't be made for it though! I do have some aluminium sheeting here, how thick would you suggest? Yes, I know of those 'heat guns', and looked them up on ebay...not too expensive but not something I would necessarily use often enough to buy...I dunno, it could become useful....I'm coming over to your neck of the woods soon and I'll be curious as to how well they work! I've been nutting this one out and I'm reasonably convinced that the factory water heater plenum is working too well. I'm either going to disconnect it completely or put a valve in there that can reduce the flow/volume. I have another idea but I will see how all this works first. I would really like to see more ignition timing than what I have now, if only to recover some of that lost top end power. Thanks mate. Cheers.

For those of you who don't know me, I'm running an L28 N42/N42 combination, mostly stock with a header and a 2.5 inch exhaust, stock cam, four barrel Holley and a 280ZX dizzy with an MSD 6AL. Stock head and compression. I changed over intake manifolds from the Arizona to the Nissan E32 four barrel intake. Virtually a straight swap, it took about an hour to do the lot. Very straightforward. The only difference is that with the Nissan manifold, I reconnected the under plenum water heater arrangement whereas I had left it disconnected with the Arizona. The Holley required some slight tuning to match the new manifold but the mixtures are as they should be, verified by my Innovate WBo2 data log. Now here is the issue, the Arizona could run with up to 17 degrees static timing. The dizzy puts in a verified extra 20 degrees, so it was total of 37 degrees BTDC @ 3500rpm. Premium unleaded, 98 octane/NGK BP6ES-II. With the Nissan manifold, I've had to back off timing to 7 degrees BTDC, 27 degrees total @ 3500rpm. Changed the plugs to BP7ES at 10 degrees but it still pinged, hence the drop to 7 degrees. Now it doesn't ping. Lost some top end power, but the midrange still feels ok. Why did this happen? Intake manifold too hot now with the water heating? (Fantastic start up though....just bump the starter and it bursts to life....very quiet idle, quite docile at low rpms, still loud at WOT though!) Outside temps hovering around 18-20 degrees celcius, not hot at all! Your thoughts and/or ideas? Cheers!

That's a long time to be sitting idle. I would guarantee a fuel leak with the carb...either internally and/or externally. Pull it off and do a thorough rebuild with a kit etc. It's not hard, just consider it essential! Told ya!

I'm assuming this refers to my comments. I'm thinking that you're not someone who can discuss a topic constructively without slander or personal attack. "Spewing some crap" is not what I had in mind. I think it's called 'advice'. Remember friend, it's up to Chris to decide which way to go and not everyone on this forum has a huge budget at their disposal......therefore the 'advice' was given with these issues in mind. If you have some thoughts on the topic, then I'll respect you for your opinions, and I would appreciate the same sort of respect in return please. At the end of the day, if we keep on track, then we can all express our opinions without fear of ridicule. I hope YOU have a good day.

For a guy who runs 11's on the quarter, almost anything would feel slow and mismatched compared to that. But from a budget perspective, what has this guy got to loose? I still stand by what I said earlier, that being the creation of a lower rpm torque monster. I had built something like this years ago, changed the diff ratio a bit (to 4.3) and smoked everything off the lights. It was all over by third gear...the other guys just scratching their heads as they burn past after you've backed off and cruising the speed limit, them reving the guts outa whatever they had....what a feeling!!!!! I'm not saying that a top end monster isn't cool, but for the money, c'mon! I say, go for it mate. Cheers.

Yes, that's a small turbo for an L28. Perhaps. Have you ever experienced full boost at 2ooorpm on an L Series before? In a Zee? Quick little bastard is all I can say....... RB20 turbo engines run twin cam heads that flow as much or more than the P90 Turbo heads in stock form. And they rev higher too.....one can possibly draw the conclusion that a T28 off an RB20DET will be fine for an L28. It just depends on what you want and where you want your power at the end of the day! Cheers.

Any setup which keeps the proper tension on the timing chain will be ok... cam tower shims or the Kameari setup. Cam tower shims restore the original distance between crank and cam centrelines, whereas the Kameari setup will not do this. Just don't forget all this work is necessary to keep cam timing as close to spec. as possible. I would invest in an adjustable cam sprocket, an eight holer is my preference but the other 'loosen adjust tighten' jobby is acceptable (Either sprocket is necessary if using only the Kameari setup without shims.) Cheers.

Ummmm, does any of this apply to an L series or is it just a general banter? Your summary isn't particularly specific and therefore a lot of assumptions and generalizations have been made. To build what is truely a 10,000 rpm engine takes a lot more planning than what you give in your description, particularly in terms of reliability and functionality. Still, throw enough money at 'it' and you might find what you're looking for. Let us know how you get on. Cheers.

There's nothing wrong with dreaming about 'what if....' The big problem you have is that you haven't done any investigating for yourself. You'll generally find that people will comment if you start off with some solid idea or concept, not some general statement about what might be possible if you win the lottery. I agree with Bart, buy yourself an RB and drop that in if your so keen on the twin cam option. Perhaps a 2JZ if you want something even more unique. The purists will hate it.

"We are the lucky country" Tony!

Call JWT....they may have details for you if they recorded the block number as part of their I.D. process. Good luck with your project. Cheers.

Those brown patches on your old HG are where there are a series of steam port holes on my genuine Nissan HG. From what I know, if steam pockets are allowed to build up, without suitable release through the holes, local hot spots form and can compromise the integrity of the HG. (Why cast 'em into the head and block if they're not needed is my way of thinking ) Genuine L28 gasket below, aftermarket version above (see pic)

I know this is a little 'off topic' but what brand of headgasket is that? Where the hell are all the steam port holes in the HG? It's so far removed from the genuine gasket arrangement, it screams!

That's a long time to be sitting idle. I would guarantee a fuel leak with the carb...either internally and/or externally. Pull it off and do a thorough rebuild with a kit etc. It's not hard, just consider it essential! Replace all the fluids as well....and flush out all of the old fuel and replace the fuel filters. I see a good couple of hours work before you get too excited about starting it. Cheers and good luck.

The runners are 30mm's, the primary holes are 26mm's and the secondaries are 30mm's. Tiny, for sure, but it's originally designed for an L20!! Gas velocity++ = Low rpm performance!

As promised, a few pictures of the E32 manifold after blasting. The interesting thing is that the 'cast in' plenum divider has two cast holes in it. There's some, but limited, mixing of the left and right halves of the carb primary and secondaries. I won't be cutting this manifold!

If you have the opportunity to put in some new valve springs...now is the time to do it. It only takes one weak or below spec spring to ruin your day with valve float and the potential disaster that can occur shortly thereafter. If you are even considering putting in an aftermarket cam, then put in aftermarket springs. Stock springs are OK for a stock cam..... just, but old ones put into a fresh head is foolish IMO. Not only that, a lot of aftermarket camshafts have valve lifts that are very close to or in excess of what lift the stock springs can handle. Cheers.

Did you measure the size of those ports? You did say they were matchported to your head....35mm's? How far up the runners did you go with the porting? Did you taper them at all? Has porting the manifold altered its flow characteristics? Would you suggest that porting with flow bench verification be a more 'scientific' approach? I'm not trying to dampen your efforts (and I've hand ported many manifolds myself) but I'm curious as to AFR's when one or several runners now flow better than the others and there is potentially no way in adjusting individual cylinders to correct the differences, unless you have individual injector/cylinder control, EGT's or individual lambda probes in each exhaust header pipe. Sure, the differences may be small but after modification, are they any better, worse or with greater variation than before? Who knows? Then there's the question of gas velocity? And anti-reversion at the port to manifold junction? Your thoughts?