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pHAT r32: WHO CARES WHAT THEY LOOK LIKE LOL :(

heres what u have to look foward to once they are set up:

after fitting the cams and doing a base run at zero zero cam setting I spent about 3 hours tuning the gears alone and achieved 20kw at the top end, 12% more torque over the entire rev range (thing about that for a sec) and spooled the turboes up 500rpm earlier> try 14PSI at 3400rpm...not bad for 3 hours dyno time and a few burnt fingers :)

Well worth while getting them set up rather than just looking at them. My settings finished on 4 degree retarded on the exh and 2 degree adv on the inlet. The main point here is the lobe center angle has been increased by 6 degrees thus increasing cylinder filling efficiency.

Mike

may i ask which cams you were using cheers

:P

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Tomei 9.15mm 260 duration...a very nice cam for a std GTR...Also just a note..upon setting up the head during my recent rebuild I watched the machinest setup cam lift and spring clearences etc ...worth noting is that the 9.15mm lift is the biggest that you can go comfortably with the std GTR springs due to coil binding problems. Anything over about 9.8mm and the coils become bound up...not good. I fitted slightly heavier, around 10 lbs when fitted, springs with less coils so I can fit a larger lift cam later on if I need to.

cheers Mike

  • 2 months later...

How much does a set of Tomei Poncams for an R33 cost? And at what stage of modification do you suggest you get them (Do they provide much benefit on stockers, or after exhaust and pod, or after major engine mods etc) or can you get good gains anytime?

  • 2 months later...

Hey guys, reviving the dead thread :P

Whats the driving/performance differences between the Tomei Type A and Type B cams?

Type A 260IN / 252EX

Type B 260IN / 260EX

Does running the higher exhaust duration ( type B ) effect low down tourqe?

I'm just trying to decide which set to get.

I'm after a nice smooth tourqe curve (street car)

Thanks

Edited by CameronBNR32
Hey guys, reviving the dead thread  :)

Whats the driving/performance differences between the Tomei Type A and Type B cams?

Type A 260IN / 252EX

Type B 260IN / 260EX

Does running the higher exhaust duration ( type B ) effect low down tourqe?

I'm just trying to decide which set to get.

I'm after a nice smooth tourqe curve (street car)

Thanks

i'm pretty sure it's the other way around mate. type a is 252 degree INLET. this is because of the theory that you can 'over cam' the inlet on an RB26 and a mild inlet cam matched with a slightly wilder exhaust cam is a good match for a street car. can't say i've tried it in practice though.

i'm pretty sure it's the other way around mate. type a is 252 degree INLET. this is because of the theory that you can 'over cam' the inlet on an RB26 and a mild inlet cam matched with a slightly wilder exhaust cam is a good match for a street car. can't say i've tried it in practice though.

sorry beerbaron but the cam duration mentioned are right

http://www.tomei-p.co.jp/_2003web-catalogu...r_engindex.html

and i believe the opposite that rb26 are normally over cammed on the exhaust not the inlet as the manufactures spec cams and some aftermarket cams combo like this combo we are looking at ,run a longer inlet than exhaust for street use. To give the best combination of power and responce.

But all that said and done the 260/260 9.15mm poncams are a awesome bolt in combo and i believe the best bolt ins on the market.

Currently i'm looking at running some procams with high lift profiles and different duration combination to see how much can be extracted from my GT2560Rs turbos last dyno sheet was 529.4rwhp(397rwkw) on the poncams and i know that TWO.06l is running poncams at 442kw on HKS 2530s (but serious boost and c16)and 10.38 1/4 mile (thats a seriously fast low mount combo)

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