thehelix112

Ballpark: 0hp+ Dave

Wierd. Damn gremlins. Dave

Thats not what I'm asking. Did the boost level out at at whatever you set it at? Ie, if you set it at 18 from a standing start, how many rpm was it at 18 for? Ie, did it reach 18 at 3500 and stay there til 6000? Or what? Dave

Mike, Very odd stuff. Oh well.. I'm not turbo guru. Dave

Mike, Sorry dude. Just like to be clear about what you're recommending. Don't really understand what you're saying about 18psi vs 15-17psi? Dave

Oh, well forget I spoke. Thats clearly good evidence. Quick everyone, unplug those wastegate lines, or better, weld them shut! Heaps faster. Dave

Could you be more vague please? Dave

Hate to be the one to raise the obvious point, but why would you? I don't think the std turbo would be pumping anything but heat at 18psi. Do it properly, or do us a favour, and don't tell us about it. Dave

drzed, take out the .th (.ThumbNail). http://img129.exs.cx/img129/6342/holset77554qu.gif Looks like the shaft speed is way up there, and the efficiency is down a bit on even the latest garret designs. Dave

Paul, Interesting. What you've said does make sense regarding the addition of oxygen (hence fuel) and the requirement of passing more exhaust gases. An additional complication with turbochargers it the restriction in the exhaust flow that they pose. The exhaust side has to be balanced such that the backpressure to the head doesn't cause reversion, as I'm sure you know. Anyway, thanks for the awesome write up. Dave

Paul, Don't ever apologise for the amount of useful information/opinions/effort you just gave us. Keep it up, PS, if you get a spare second (hehe) would you give us some information about a FI setup? I would assume everything is identical. Flow is flow, but some ancillary considerations come into account. Like a N42 head closed down might require dished pistons, which in turn might increase the necessary pin-height required. The context I am talking is no-expense spared turbo race engine. Everything custom (if necessary), including crank, rods, pistons, crank girdle, etc etc. Cheers, Dave

I'm curious John, did the build up the combustion chamber to make it peanut shape like the P90? Dave

Tony, Thats not being pedantic, thats common sense. Dave

http://www.classiczcars.com/forums/showthread.php?t=18689 Basically depends what you HAVE to keep. If you need mech throttle, must keep towers. If you have std EFI, must keep most of the crap. If you have aftermarket EFI, rip it down to a complete bare manifold, then take lines off where you need them (MAP sensor, fuel pressure reg, BOV, brake booster, wastegate line, air temp sensor) and plug everything else. Dave

Oleh, Is a custom manifold. Built by a kindly old TIG welder for his race 240z. ON3GO, I think gollum was just mentioning possibilities, not saying that your setup had more lag. I personally think the radiant heat absorbed by the intercooler pipes would be almost identical for both setups, the entire engine bay is going to get hot unless you have some serious bonnet ventilation. But I suppose the crossing rad after cooling would get slightly hotter, bet it'd be by fuckall though. Dave

Tony D, If you're going to be that pedantic, garrett didn't say Turbocompressor wheel, he said turbo compressor wheel: obviously a truncated (short-hand) form for turbocharger compressor wheel. Garrett, You can replace the wheel yourself just fine, but as SleeperZ says, you will need to get the assembly professionally balanced. Seems a waste to replace the entire cartridge just for the compressor wheel, but I'm not sure on prices. Dave

Looking pretty damn tidy there Mike. Good work. Any reason why you routed the turbo outlet to the other side for the intercooler input? Seemed more logical to do it the other way on my setup:

While I wouldn't discard the detonation theory just yet (I'm no expert on these things) one other option to consider is that the missing shard of compressor wheel entered #2 cylinder and proceeded to wedge at the edge of the piston/chamber. This then meant that the piston was running into it and then into the head accounting for the obvious metal-on-metal in the rod big end. Of course, this assumes that the shards are big enough to do this, but small enough to make it through the IC? Checked the IC? Dave

Reason? Dave

John, Thanks for the honest reply. I wasn't trying to be a pain, just asking. Dave

Interesting. I always thought (according to several books which I can't remember right now) that the F54 blocks, with siamesed cylinder walls between 1-2, 3-4 and 5-6 were more rigid. They are the blocks that were used in the 600hp SCCA 280ZX cars. Dave