Robert

Its not the valve clearence, but if they make noice, you should adjust them, but thats not your problem. First things first,check your timing, and then your ignition system (plugs, dis cap). If you have problems getting high rpms (3500+), the dizzy could be broken, have seen this quite a few times. Either ignition module or excessive shaft play causes misfires, and the inability to reach high RPMs. If none of the above helps you, you could try going through the FSM. The FI system generally is very reliable, but shure, sometimes they fail. but most times, the problems are the easy stuff, like a part clogged fuel filter.

Thanks, Ill check my pumps later on!

I have 2 different oil pumps laying around, and I was told that one of them was the high flow turbo pump. There are some numbers stamped on the side, and they are different, but does someone know if they can identify the pump? The reason I want a high flow pump, is that Ive installed a turbo on my NA engine, and I want to install a oil cooler as well, increasing the need for more flow.

Id say its every time, and gets worse the harder my driving is. Thats why Im afraid its cylinder pressure... Changing radiator caps did not help

NGK has always served me well. I once had a high strung rallycross engine, that would not run for more then minutes on the often so good Denso plugs. But some random NGK plugs went fine a whole race weekend.

I did test it without finding leaks before I stripped the engine, but shure, I could try again, hard to believe its the head gasket or cyl head..

I recently overhauled my engine. Metal head gasket, flat cyl head. But when Im driving, and especially under boost, the coolant overflows into the overflow tank! Is there any "typical" reason for this, except the obvious head gasket or cyl head? L24E T4 Turbo 23PSI boost HKS head gasket HKS SR20det high flow 63C thermostat No overheating, except when the water goes low (takes about 30miles with some fun road driving) Any good ideas? This was one of the reasons I overhauled, the cyl head is swapped for one that I know works, and Its straight.

Yea, the IATs cant be compared, I live in a cold country.... Thats probably one of the reasons Im running more aggressive on the spark, but there could be many. I have no knock problems, so I wont change it any time soon. Typical IATs here is less then half of yours by the way. Wrong forum, yea. Ill delete and rewrite.

If this is true, then a very rich mixture could help on knock.. I have the problem myselfe.. Interesting. But was this test performed on a running engine? Im just thinking, If its just the intake he tested, then this has little interest, cause if nothing stops the flow, theres no pressure build up in the manifold, and ofcourse #1 gets less then the rest......Is there a link to the rest of the testing? Or maybee a solution? First thing I could think of was cutting the fuel rail in half, and increasing fuel pressure on #4-6 compared to 1-3...

First off, as said before, the problem is not there when the internals are cool, first after some hard runs. AF VS Knock depends greatly on spark advance. Less spark and less fuel can give the same power. Knock is simply that the "peak" of the detonation comes before TDC. A lean mixture burns faster, so you would need less spark. Add more fuel, and you can add more spark. If it gives more power has been discussed for ages. I think so though. Anyways, hope you see my point. Theres no "the rich or lean for that engine". I cant pull any boost, but I can add fuel. AF goal table is added as an attatchment. As you can see, Im trying to get 11.5, Im just not there yet, cause Ive only had a few miles of tuning before this knock problem came to my attention. If you read the whole thread, youll understand more. Also added is my spark table. You may review it, but again, thats probably not where the problems are though, cause then the knock would be instant, not only after emptying one or two gears, and even if it was after emptying some gears, and the IAT went sky high, it WOULD NOT be as extreme (it sounds like the pistons hit the ground!! Worst Ive ever heard!) Edit: As you can see from the AF table, the AFs are richening up more and more from 12-11.5 from 180 to 260KPA (~12-28 PSI). This should be good. IAT retard will be enabled if needed. Ill start looking at my problems today, and see where I end up.

Moving to new forum

Nope. If we go extreme, you probably cant run a 600bhp engine with 40PSI, but Im tempted to try close to 30 on this ~8.5:1 if I can fix my cooling.

AFs are down to low 12s and 11s without maxing the injectors out, so YES!

The knock comes mid range, but probalby at any RPM with boost. I live in a cold place, 70F out temperatures. The highest EVER datalogged IAT temp Ive seen here is ~95F (35C). Big intercoolers that get air is the best Btw a water injection system is currently being assembled as another anti knock solution. Like stated before, Ill check back in when Ive tried the cap and water wetter. Shure, IAT will be connected, Ill datalog a bunch of gears for you.

Sandblast, or use a steel brush grinder and see how they look when the rust is of. But as others mentioned, the surface must be smooth, so If the surface is rough, you must use some fine paper to smooth things out. On a side note, I ordered pads directly from Nissan motorsports, and they were very quick to ship out some excellent looking pads..

Hi! I think these engines are indestructable, Ive never seen a engine hanle as much Knock as the previous L24E we turbocharged.. I have a N47. I can get my hands on a N42, but I really enjoy the bottom end pull of my engine, so I wont go there. I suppose thats what you use as well? I use a 36-1 trigger wheel on the crank wheel, with a Megasquirt controlling ignition timing and fuel injection. I use the dizzy for the moment, but Im planing to install a wasted spark system in time using SR20DET CoilOnPlug. The COP system should allow about .6mm spark plug gaps, 3 times what I use today, resulting in a much better combustion. Do you use fuel only, or did you manage the "impossible" and trigger of the stock VR sensor?

I said maybee, and I stick by that. But again, I dont think its that easy, just speeking from experience, 2 hard pulls with an intercooler rearly increases temps by much more then 1-5 degrees, of which pulling 1 degree of ignition timing or so should fix it, and it DOES NOT. And it seriously sounds like the pistons are banging the asphalt, worst knocking ive heard since.. Well, the last time we turboed an L engine actually Must have been the same thing there.. These engines must be indestructable.. Oh, and I wont tune it another second until I get a water wetter and higher pressure in there.. Im convinced this has to do with the #5 hot spot, or possibly a spark plug going hot (dont think so).. While at it, Ill connect the IAT, Ive just waited for the bloody connector to come in my mailbox.. Slow progress though, so much to do, and so little time

Maybe. But after emptying the 3 gear second time (when knock comes), the pipes are`nt even beginning to glow.. So I dont think its that easy, and I wont be doing any pressure testing. Ive got a T3 .63 housing.

But theres no knock until Ive emptied a few gears and made it hot and nice in the cylinders, so the octane is good until something, somewhere gets hot.. With good cooliong I could, If I for some stupid reason wanted to, run a lower octane, Id just need to lower the ignition timing. Oh, and remember 25PSI on a medium size turbo is not the same as on a large one. HP is not much over 300 BHP. I think. Heheh:)

If I remove the core, there will be a restrictor... This car is used on street as well, but Its built to outrun cars with many times the budget on the tracks, simply to show the Nissans superiority, and for fun, LOTS of fun! Nothings like a sleeper! Anyways, Ill see how a no core thermostat works, and get back to you.

As this is a datsun L forum, I dont think Intel will get too pissed if we use oil on our gaskets.. And I really cant see the reason for reading a book during assembly of most engines, with exceptions of very new and advanced engines, and in some cases tightening torques etc (like newer BMW`s with magnesium blocks and so on), unless you are totally green, in which case you would be stupid If you just put it together and see how it works. Just my opinion. So use the book if youre not shure of what youre doing, or not shure on something can be the new rule of thumb

Thanks for the summary, lots of great info in a small place As for AFfuel delivery, I have no problems there anymore. As discussed in another thread, I maxed my injectors earlier, this got resolved with a "cowboy" increase of fuel pressure, and a new filter.. The plugs are Denso with NGK7 heat range. I used NGK 9s in teh beginning, but they where to cold, and I had to burn them clean every time I started the engine.. I am considering to put them back in now at this late stage of tuning, just to check. But I recall having the same problems in when they were in, but that was in the starting phase of tuning, so I never linked it to anything other then AFRtiming issues. Before any further tuning, a water wetter, no core thermostat and high pressure cap will be installed. Ill tell you how that worked for me!

Well the thing is, this dont "feel" like IAT problems. they generally come on slow tracks, after several laps, or in very high temperatures. Here, the problems come after a couple of hard runs.. As if a plug is to warm or something.. The build: Stock L24E Megasqurt 440cc injectors Walbro pump Stock FPR, but modified rail for higher pressure and better flow Intercooler T04E turbo 300+ BHP (gut feeling) *edited*

Hi, Yea I thought of that, but I figured if you remove everything and leave the metalplate in there as a "braeak", it should work as a fully open high flow thermostat.... ? Im running 98 RON, I think its about the same as 94 premium in the US? But with full ignition control, the octane dont matter to much, unless you have a bloody hot spot in the cylinder head

So a note to myselfe and maybee others on the cooling issue: The musts or "DuÙH"s: Premium fuel, highest possible octane A cold thermostat or none at all <<-- Im thinking of removing the core in mine, leaving a "constant open high flow" thermostat. The easy mods: Water wetter -- http://www.summitracing.com/parts/RED-80204?autofilter=1&part=RED%252D80204&N=700+115&autoview=sku Higher pressure radiator cap Octane booster (expensive!) More advanced: RD28 water pump with large impeller Only for the extreme: Tap into the cyl heads #4 #5 #6 with seperate water lines to increase flow around #5 Reverse flow of the coolant