R32Abuser

Just thought I'd update with whats going on with the car. So todays events went as follows: Wish I could have been present but was unable to due to work. However they (builder and tuner) tried a few things. Not as many as I would have hoped but still... Things which were changed a) spark plugs b) CAS c) timing d) tune Ok, so car rocked up on the dyno. Builder/tuner verified timing/base timing, checked a few things, then proceeded to do the first run. What do you know- it didnt ping/knock at all. Made about 225-230RWKW with bugger all timing again (probs in the vacinity of 7-8 degrees). Boost was apparently around the 15psi mark but the tuner had to redo the boost control as for some reason it was all over the shop. So on the story went, and the more runs they did, the more the engine wanted to knock. That was until the 7th or 8th run loading it up etc. and then it went back to how it was the other week. Tuner tried a few things, chucking more fuel in, playing with timing etc. Then the tuner/builder decided to just give it a safe tune with bugger all timing (6 degrees) where I presume it wasnt pinging too bad (apparently). For some reason the boost was left at like 17-18 psi. To me I see this will cause more detonation when its just not needed! Back to square one... So the builder drove it back to the workshop. Said the thing would ping at anything up around the 5000RPM mark, not even thrashing it too much. So the decision was made by him and myself not to drive it at all. On the positive, I guess the conclusion could be that this problem is somewhat heat related. Heat Soak? The cooler was cold to touch on the outlet side, and warm to hot on the inlet side. Crossover pipe was warm to hot to touch but nothing too bad. Have you guys got any ideas as to any potential problems you've had previously with heat and anything like this? As for intake temps, I wasnt told anything, as I had limited time to speak with the builder. But will be doing so quite soon. Just brainstorming, but coil packs could almost be ruled out. These would usually cause a misfire and a lack of ignition and "WRX" sounding motor, rather than knock. Igniter was also suggested-not entirely sure whether this would cause the same issue as coil packs but its something to try. One thing a mate suggested was to drop the dump. See if its backpressure causing excessive heat. Got any other suggestions? Builder wants to try cams. But Im sceptical. Im at my wits end and most likely want to take it to another tuner for trouble shooting. Any help you can provide would be great! Cheers, David

Not at all harsh. You know I respect your advice Cubes Plan is to try the stuff I mentioned first (CAS, Plugs etc etc whilst on the dyno). If nothing comes of it, then put a safe tune where it wont knock at all (who cares about power). Drive it to get some k's on it. Then Im not sure where to go from there. Ive emailed several tuners and got their advice. So we'll see how we go from there. Either way if this doesn't fix it come Monday, Ill be taking it somewhere else for a 2nd opinion/fault check. For now, Im just looking forward to Monday to see if anything will change and to get my car back...FINALLY!

Yeah. I have a good feeling that this definitely would not be helping the cause with regards to keeping pinging at bay. Will be changing them for the tune on Monday.

Will do. Cross my fingers everything goes well and the issues dissapear. Got in contact with Sydneykid and he has given me some points of reference to start at with regards to troubleshooting. Hopefully he narrows it down and fixes the problem. Quoting Sydneykid aka Gary, This is also what Cubes suggested aswell. I think maybe chucking a set of regrinds may help. This is something I will do in the coming weeks/months. He also suggested using a different spark plug heat range (7's as opposed to what is in there now (6's)). Something simple which can make the difference. Also suggested a leak-down test to check the run in has gone according to plan. Problem is if it pings/knocks etc. with the new CAS and other gear then we cant get a proper tune as it will end up destroying the motor. Not really something I want to do given the amount of money and time which has been invested.

Yup. Builder is slapping a different/known working CAS on it. Taking it back to the dyno, checking if it knocks again, if so, getting a safe tune to do some k's on it. If not - great!!! Thoughts?

From all that I've read, and from thinking about it: If the piston (flat section of the piston-not including domes/dish's) sits below the deck of the block, then the combustion volume when the piston is at TDC is larger compared to if the piston was sitting above the deck ("proud of the deck"). Correct me if Im wrong tho?

Plus they look like everyone else's 6 cc CP pistons.

99.9% sure when I called him he said they were the 6cc domes.

Ive done a few investigations and by using online calculators and inputting the following: 6cc dome pistons (Confirmed many times via R33 RB30DET thread/Spool Imports) 1.28mm Head Gasket (0.05") (Cometic) (Confirmed via Spool Imports) 86.5mm Stroke x 86.5mm Bore 0 Deck height (From speaking to the builder, the deck height is actually below 0 deck height (decreasing compression!) exact value Im unsure of) 62cc combustion volume (Head type Confirmd by Cubes as being an R32 RB25DE head. Also, 4 different R32 RB25DE heads all cc'd to this value - so the only way mine may read less is if it had been seriously overheated and decked to get it straight again) Standard pin height 1.280" (As confirmed by Spool) Approximately 9:1 (probably less due to pistons being below deck height) A few online calculators ask for teh HG bore. Without it infront of me I can only guess, but all in all, EVERY different calculator got approximately 9:1 Static CR. Is there something im missing?

As rolls said 207RWKW on the 7-8 deg of timing. AFR's were apparently spot on. Been doing a few calcs here and there and all are coming back the same... Approximately 9:1 pending a few things. The only thing I'm not 100% on is the chamber volume. Im 99% sure it is as per Bl4ck32/Cubes measurements at 62cc. That is unless there was a serious issue with the head being overheated earlier on in its life. I just cant be too sure unless I get it measured... Anyone got any ideas on how much (an average value) they would take off a warped head to see it flat again?

Something I am curious about. From where Im standing, I believe it may be one or a combination of: a) Cams - As Cubes stated, the R32 RB25DE head causes the motor to ping easier than normal b) Cam timing - Possibly issue with CAS, or base timing c) Static CR (assuming the head is approx as Bl4ck32 stated) - the 9:1 CR would make the motor more succeptable to pinging than say an 8.3:1 motor. However, I dont see this as being the issue right now until we've ruled out timing. However, I have heard two VERY different values for the head cc measurement which has caused some confusion. One thing to note is that the tuner had dealt with a Stagea RB25 Neo with similar/same pistons. Same symptoms. Put E85 in it and it was all good and made plenty of power. Always options to consider...

As for the tune- I believe it was a "power" tune. After that, drive for 1000km, not too harsher driving, then drop old castor oil and put synthetic in. I may stand to be corrected tho so don't take it all as gospel.

I believe you Darren just seeing if others have found different heads etc. I wasn't there so I can't speak for the tuner, but it was audible enough for the tuner to stop the tune!

Motor has been "run" in on the Dyno for about 30mins to bed the rings and bores in. Still on thick castor oil until 1000km. Cams are all standard as well as cam gears. So no real adjustment there. Spoke to a couple of blokes last nite who have built pretty much the same setup as me except pistons. Can anyone confirm the head cc of an R32 RB25DE?

No catch can setup. Tuner said it was an audible knock. I.e. didnt need a sensor to hear it! Knock sensor reflected this aswell. Im soooooo confused right about now!

Comp test was 160 odd across the board...Was promising before I had talked to Paul from Red R Racing. Paul says that after doing a back calculation using those pistons with the head I have (obviously with some small assumptions) the static C.R. will be sitting in the 10's. The only reason I bought those pistons was on the basis that those heads are listed to cc up 62-66cc between the three - as listed in the RB30DOHC pdf. Hence the C.R. should have been around 9. Pretty upset that its come this far to find this information out... That said, I still have options. Timing is apparently being checked tomorrow, however, after talking to Paul - I doubt this will make a difference.

Comp test was 160 odd across the board...Was promising before I had talked to Paul. Paul says that after doing a back calculation using those pistons with the head I have (obviously with some small assumptions) the static C.R. will be sitting in the 10's. The only reason I bought those pistons was on the basis that those heads are listed to cc up 62-66cc between the three - as listed in the RB30DOHC pdf. Hence the C.R. should have been around 9. Pretty upset that its come this far to find this information out... That said, I still have options. Timing is apparently being checked tomorrow, however, after talking to Paul - I doubt this will make a difference.

6cc dome ones. Spoke to Paul and will be speaking again tonight. Not looking good

You sure? The RB30DOHC thread quotes: "Three heads can be used for the twin cam conversion. • RB26DETT Head • RB25DE (R32) Head • RB25DE/T (R33) VCT Head All three heads cc up around the 62-64cc mark." Im not taking it as gospel, but that a fair difference in cc stated in the thread as opposed to in the actual head. In any case, the engine builder/assembler should have cc'd the head to check this!

I was told that it was audible knocking. Not off a sensor, but the sensor was indicating that the motor was knocking. Ill run this by the tuner/assembler. Cheers Guilt-Toy. Ill update as soon as I know anything more.

No references...? So many credible source must agree with your argument though. Right? You must be correct though...Nissan (and majority of manufacturers) have done, and continue to do it wrong. You dont need dowels on the flywheel.

Let me ask you this... Assume the clutch and flywheel assembly is at rest. Induce a torque (via the motor) onto this assembly so that it will rotate. Now, suddenly, the flywheel is instantaneously stopped. Newtons first law states that the clutch asm will want to continue to rotate. We all know that it will cease to move a very short time after the flywheel stops rotating due to these two items being attached to one another. What part of the flywheel/clutch assembly transfers this torque reversal? Would you agree that it is the locators/fasteners which fasten/locate the clutch assembly to the flywheel? It has to be...there is nothing else attaching these two indivdual parts together. Now, if the dowels are toleranced tighter than the bolts themselves, what else will transmit this torque reversal? Also, Since this assembly is not counter-weighted, and since another member has stated that locating is not important, then why are the dowels there? I agree that in some setups (aftermarket) there is no dowels, but does that automatically make them a good/better design?

Same could be said for yourself judging by a few of your last posts here and elsewhere. Sounds alot like tha garbage talk you hear over on NS.com. The fact that you feel the need to personally attack someone to get your point across does not add strength to your argument. No references to back your argument by any chance?

Spoke to assembler today... Compression test still yet to be done AFR's were apparently spot on. So besides the pinging nothing is too suggestive!!!

Spoke to assembler today... Compression test still yet to be done AFR's were apparently spot on. So besides the pinging nothing is too suggestive!!!