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anyone know much about R34 GTR engine harnesses? Found one for sale on the Jap auctions and just wanna know if everything is there.

Apparently they are very hard to find and can be very expensive. This is roughly $500del

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anyone know much about R34 GTR engine harnesses? Found one for sale on the Jap auctions and just wanna know if everything is there.

Apparently they are very hard to find and can be very expensive. This is roughly $500del

yep, looks all there to me! :(

hehe.. depends on what falcon.. the older ones are plagued with crank end float issues and head stud problems. :D

Falcons definitely a better pick than the commodores especially for towing. :mad:

See if you can pick up an old EF/EL 4ltr 5speed then umm strap a turbo on to it. 1550kg kerb weight vs the BA's 1700-1800kg. = power to weight FTW :wub:

I used one of those cheap $5 1/4" drive ratchet kits from supercheap that come with philips head bits. You can get heaps of weight on to it + leverage so they crack easily.

Thanks cubes, will give that a try :(

I haven't actually played with the cam gears yet.. Left them as is as there's still a bit of work to be done with the 2" fmic piping etc.

Im still getting my head around cam specs etc..

My understanding is there's:

~39degree's overlap seat to seat and -4degree's overlap at 0.050"

R32 RB25DE cams:

~8degree's overlap seat to seat. No idea at 0.050". All though I believe 0.050" overlap you ignore?

R32 RB20DET cams:

~5degree's overlap seat to seat.

R33 RB26:

~7degree's overlap seat to seat

So it is running a fair whack of overlap. I was pretty way off.

Ok, where do we start.

Your cams have 112deg of separation from IN to EX lobe centres which does not give you the actual overlap figure (can vary depending on lift & lobe profile).

I made a mistake in calculation in the earlier post and said you had 50deg overlap when its actually more like 40deg (I based it on a 25/65 grind rather than a 20/65).

Like I said earlier, when you increase duration you generally increase overlap so normally I would suggest you pull the IN & EX lobes further apart with gears and actually consider a figure of around 116deg of separation, but in your case I probably wouldn't bother if you're already getting good low down flexibilty.

Cranking pressure now sits at 155psi vs 158psi with the std cams.

But whats wierd is this engine analyzer pro is stating there's 28degree's of overlap?! :S

Not unusual although I expected that you would've pulled a little more compression out of the cylinders than you actually did, so its not too bad.........as for the analyzer, send it to a shrink to get analyzed :P .

On the note of compression, so many peeps opt for thicker head gasket shims in order to be able to run higher boosts but they forget you can do it with cams. So when they do cams and thicker head gasket at the same time, they wonder why they've lost so much compression. A little bit of compression is what makes the RB's so nimble so you don't want to dial out too much.

The cams are unfortunately as big as you can go without seriously looking at valve springs, solid lifters and machining the buckets. The 26 head is a much better starting point for 350rwkw+.

Yeah I agree, you've got a good street grind there with a smidge under 9mm lift which is the main determining factor for what springs and retainers you run, so your current springs (if in good order) will be fine. Definitely need to use different springs once you go over 10mm of valve lift. Good thing about RB's is 1:1 ratio unlike other engines that have to factor in extending rocker ratios as well. ;)

What I have unexpectedly experienced is a very noticable improvement in economy. We didn't play with the ignition map its the std rb26 one. The afr's were set back to 15:1 and that was it.

Driving the car to work the last week and quite a bit of driving on the weekend its consistently floating between 10.5-11L/100km's. The last tank pulled 480km's out of 52litres.

Hmmm, thats a tuffie.

I'm assuming 15:1 AFR's is at idle only and even thats abit lean, should be around 14:1 but I dont think that really matters too much.

I need to see your graphs to see what the rest of you AFR's are doing. The guy may have pulled a fair whack of fuel out of the map which could explain the good economy.....hope its not running too lean :P

I wouldn't mess with the ignition map yet until you determine what yo want to do with the gears. Pulling out abit of valve timing will alow you to advance the ignition a bit more without the extra fear of detonation.....so you gain a bit more power and bring it back where its a bit more useable at the same time.

You may be able to help me get my head around the following.

Retarding (or is it advancing?) the inlet cam does that numerically increase the Inlet LCA which widens the LSA and as a result decreases overlap.

And the exhaust.. retarding or advancing does that increase the LCA or decrease numerically? :S

Inlet LCA of 115, Exhaust LCA of 118 gives an LSA of 116.5 and 31degree's of overlap. Reduced overlap might help that restrictive gt30 .82 rear end up top.

Pretty much as I said above, but at the end of the day its all about how it feels on the road.

I'd start with about 4 degrees reatard at the crank (2 lines) on the EX cam gear and see how it looks on the dyno.

Just did a search.......Check out SK's thread that probably explains it better than me....I'm definitely no RB guru but he is.

Adj Camshaft Pulley

Well guys it looks like were putting off that SAU cruise/bruise past the dads place then. ;)

haha, yeah I think that idea has been shelved temporarily.

I was gonna back up the 300 tyre over his head :P

Hey Amanda......tell him if he messes with you, he messes with the whole SAU family........he may wake up with a horses head next to him one day :P

Ok, where do we start.

Your cams have 112deg of separation from IN to EX lobe centres which does not give you the actual overlap figure (can vary depending on lift & lobe profile).

I made a mistake in calculation in the earlier post and said you had 50deg overlap when its actually more like 40deg (I based it on a 25/65 grind rather than a 20/65).

Like I said earlier, when you increase duration you generally increase overlap so normally I would suggest you pull the IN & EX lobes further apart with gears and actually consider a figure of around 116deg of separation, but in your case I probably wouldn't bother if you're already getting good low down flexibilty.

What the hell are you kids talking about ? You sound like a bunch of darned star trek fans

-D

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