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Tomei Poncams Installed ! Hmmm power...


rev210
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I'll race you mate ;)....yes it's been a long journey Ronin....work comes first for me unfortunately...thats the main reason.

Just brought my new business, its a diesel,turbo, performance dyno workshop...what a combo :D We have a dyno dynamics dyno which I have given a birthday too when I moved in! I'll be doing my own tuning and will publish the results here on this thread.

Mike

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Just curious... I want to put some cams on to increase the torque and mid range.

My Power Mods -  

Power FC + HC

Full Exhaust (hi flo cat, split dump, very free flowing exhaust)

Stainless Turbo to AFM Pipe

Shielded Pod Filter

600x300x75 FMIC

12psi

HKS Exhaust cam gear set at 0 degrees

Stock Turbo, stock motor, stock everytyhing else.

Heres my dyno -  

209rwkw.jpg

I want to get a set of tomei cams, but the problem is I know nothing about cams...at all.. I know they can make the car idle rough, but that isn't too much of a problem for me. I just want all that torque.

So... does anyone have any educated suggestions?

I also want to accomodate for a bigger turbine later on down the track...

yer what he said i know nothing about cams either got a r33 gtst basically the same anyone help us

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Ordered Tomei 260 IN/EX 9.15mm lift, should get them next week, will post up results aswell.....

Other mods, Jack?

will be interested to see how your results stack up against mine... which dyno to tune it?

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Other mods, Jack?

will be interested to see how your results stack up against mine... which dyno to tune it?

I don't think its a fair comparison...

Rebuilt motor

Trust T517z turbos

etc...

Currently running 335 rwkws (21psi), on Racepace dyno...

Ben will install and tune once i get them....

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culodofsomke & The Mafia,

On my old R33 gtst I ran the standard VCT intake cam and a HKS 264deg exhaust cam (biggest lift you can get without machine work). It's an excellent match, one of the guys on this forum ran it through the cam matching software, he uses at work (works at a camshaft manufacturer) before I went ahead and it worked out in real life just as planned. About 20hp up in average horsepower over the same stock setup and a faster& earlier turbo spool up to boot. Overcamming the intake side is something that is all too easy to do on a turbo motor. On the Rb25 the most help is needed on the exhaust side of things.

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culodofsomke & The Mafia,

On my old R33 gtst I ran the standard VCT intake cam and a HKS 264deg exhaust cam (biggest lift you can get without machine work). It's an excellent match, one of the guys on this forum ran it through the cam matching software, he uses at work (works at a camshaft manufacturer) before I went ahead and it worked out in real life just as planned. About 20hp up in average horsepower over the same stock setup and a faster& earlier turbo spool up to boot.  Overcamming the intake side is something that is all too easy to do on a turbo motor. On the Rb25 the most help is needed on the exhaust side of things.

thats awesome advice. So your saying that I won't need to change the intake cam at all?

I want the car to sound a little lumpy, but not too lumpy to be a daily driver. I'm more interested in torque increase.. From Low to Mid range.

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so the poncals are great, but im confused about the camgears, can they be tuned to produce more power? do you need 2?

steve

not sure what mine are set at, but I'm pretty sure that it is better to 'dial in' the cams using adjustable cam gears - ie at 0 degrees for both is probably not optimum. If you don't do the cam gears, the money spent for the cams seems like a wasted exercise if you don't optimise them.

I seem to remeber that SK said however that the RB25 poncams were good at 0 degrees...? I can't exactly remember the details but it's in one of the cams threads

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I just need to clear something up here, I have used the Tomei 256/260 Poncams in 2 X RB25's, one Neo in an R34GTT and one non Neo in an R33 GTST.  Neither of them benefitted from having an adjustable exhaust camshaft pulley, they both made their best average power at zero degrees adjustment.   The Poncams work very well with the VVT, I kept it, so no adjustable inlet camshaft pulley.

This has not been my experience with GTR's, they ALWAYS benefit from adjustable inlet and exhaust camshaft pulleys.  The more extensive the mods, the more they benefit and no two engines are the same.

Hope that clarifies:cheers:

:cheers:

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thats awesome advice. So your saying that I won't need to change the intake cam at all?

I want the car to sound a little lumpy, but not too lumpy to be a daily driver. I'm more interested in torque increase.. From Low to Mid range.

Won't sound lumpy at all, it idles like stock.

Changing the cams depends on alot of things.

If you are after low- midrange power then you can't do too much better than factory cams with adjustment to the exhaust cam timing.

With any larger duration aftermarket cam you will lose some low rpm power but pick up midrange and top end.

If you want a lumpy idle you can't go past rotational idle on an ecu like the autronic.

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I think there is one thing to take into account when concidering adjustable cam wheels and the tuning of them

*the cam timing to crank relationship on different motors can varies due to machining tolerances (tall block ,tall head and short cam belt etc etc)and yes i know we are not talking much here BUT i found by adjusting my poncams on my gtr 1deg of cam wheel rotation gave a gain of 30hp, SO YOUR CAM WHEELS MAY HELP YOU TO SET THE TIMING BETWEEN CRANK AND CAM TO STD(not always to a different setting), as every motor like Sydneykid said is different.

So my advice would be to buy and try adjustable cam wheels (esp on gtrs) but get them tuned by someone willing to take the time to set them properly

My R33GTR gain over 100rwhp

Rep003 rb26 4 door auto gain around 50rwhp on std cams

so it worth a try

pete

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My R33GTR gain over 100rwhp

Rep003 rb26 4 door auto gain around 50rwhp on std cams

so it worth a try

pete

Mine only gained 3rwhp compared to zero/zero setting however the usable power dramatically improved. In the lower to mid-rpm range I have up to a 38rwhp improvement across the range, i hit 1 bar at 4000rpm not 5000 & it maintains good power to 8500rpm not 7900 as before.

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Mine only gained 3rwhp compared to zero/zero setting however the usable power dramatically improved. In the lower to mid-rpm range I have up to a 38rwhp improvement across the range, i hit 1 bar at 4000rpm not 5000 & it maintains good power to 8500rpm not 7900 as before.

nice result and like i said every motor is different, but you would agree it was well worth the effort :P

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

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

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