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Hi all,

I'm over in the Uk, haven't been on the site for a little while but i'm hoping that some of you guys can help me out as you have alot more knowledge with N/A Skyline's than us lot!

I've got a '96 R33 GTS with the RB25DE.

I've just completed having individual throttle bodies fitted and mapped up etc.

Current tuning mods are:

Emerald K3 ECU

Custom made throttle body set up using GTR throttle bodies, Jenvey trumpets and Piper X filter socks

Uprated coilpacks

Wasted spark set up

Coby D12 exhaust manifold

Custom Powerflow 2.5in exhaust system

Tomei adjustable cam gears (only the exhaust one fitted atm where NVCS has been removed)

A/C removed

The car's acheieved 201bhp at the flywheel and now rev's up over 7500RPM.

Power delivery, torque and fueling have all smoothed out.

We're now looking to extract some more power.

There's a shift function on the ECU which means the other adjustable cam can be fitted and should she another 30-40bhp.

We're looking at doing something with the cam's next.

Does anyone do aftermarket cam's for the N/A?

If not, can the standard cam's be reprofiled to be more efficent?

If so, what's the best profile?

Any other info on cams or anything else i can do to futher extract more power will be greatly appreciated.

Here's a pic (sorry pic quality ain't great) of the set up so far!

DSC00744.jpg

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https://www.sau.com.au/forums/topic/304833-need-your-help-cams/
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Hi all,

I'm over in the Uk, haven't been on the site for a little while but i'm hoping that some of you guys can help me out as you have alot more knowledge with N/A Skyline's than us lot!

I've got a '96 R33 GTS with the RB25DE.

I've just completed having individual throttle bodies fitted and mapped up etc.

Current tuning mods are:

Emerald K3 ECU

Custom made throttle body set up using GTR throttle bodies, Jenvey trumpets and Piper X filter socks

Uprated coilpacks

Wasted spark set up

Coby D12 exhaust manifold

Custom Powerflow 2.5in exhaust system

Tomei adjustable cam gears (only the exhaust one fitted atm where NVCS has been removed)

A/C removed

The car's acheieved 201bhp at the flywheel and now rev's up over 7500RPM.

Power delivery, torque and fueling have all smoothed out.

We're now looking to extract some more power.

There's a shift function on the ECU which means the other adjustable cam can be fitted and should she another 30-40bhp.

We're looking at doing something with the cam's next.

Does anyone do aftermarket cam's for the N/A?

If not, can the standard cam's be reprofiled to be more efficent?

If so, what's the best profile?

Any other info on cams or anything else i can do to futher extract more power will be greatly appreciated.

Here's a pic (sorry pic quality ain't great) of the set up so far!

DSC00744.jpg

you can regrind your cams to get more lift but duration is not so easy becareful revving it to 7500rpm the hydraulic tappets don't like it

this is how an NA RB should be done :D

Most after market cams are to suit turbo cars

.

so head over to camshaftshop.com and get kelford to make you up some big bastards to suit the NA throw in some better valve springs and if you can afford it a solid lifter coversion (just make sure that if you do the solid conversion that you get cams to suit)

Next step rev that bad boy to 9000+

Cheers all for the good comments!

I'll get a vid up soon and some better pics, picking her up next week as it cost me a lil bit more than i expected! lol!

She drives soooooo smooth tho and the sound! ;)

Hesh! send me a tx mate, i lost your number when my phone got repaired, they wiped the bloody memory! :)

Thanks for the info on the cams and cheers zebra, i'll check the site out!

I'm running ITB's on an RB20DE in my rallycar. Still a 2ltr for class requirements.

I don't have the exact spec of the cam's on hand, but they are 280° duration and max lift we could run with the standard lifters/followers. The head has also had a lot of porting done, although I feel we may have gone a little too far on the port size and cams. It pulls strong for a 2ltr, but is very fussy on intake length adjustment and doesn't have the torque I'm looking for yet.

Cams are a custom grind made by Kelford Cams, as no one really has any spec's on ITB N/A RB motors. I would say the 2.5ltr will be easier to strike the right tune with the cams thanks to the extra capacity. To me it sounds like you are after peak hp and rpm? I'm after the opposite, however the 'lil bugger does like to rev to 8,500rpm all day long on the stock bottom end. Oh and the sound!! :P

Vids' FYI

-motor is too flat below 4,000rpm

Edited by screamin'
I'm running ITB's on an RB20DE in my rallycar. Still a 2ltr for class requirements.

I don't have the exact spec of the cam's on hand, but they are 280° duration and max lift we could run with the standard lifters/followers. The head has also had a lot of porting done, although I feel we may have gone a little too far on the port size and cams. It pulls strong for a 2ltr, but is very fussy on intake length adjustment and doesn't have the torque I'm looking for yet.

Cams are a custom grind made by Kelford Cams, as no one really has any spec's on ITB N/A RB motors. I would say the 2.5ltr will be easier to strike the right tune with the cams thanks to the extra capacity. To me it sounds like you are after peak hp and rpm? I'm after the opposite, however the 'lil bugger does like to rev to 8,500rpm all day long on the stock bottom end. Oh and the sound!! :thumbsup:

Vids' FYI

-motor is too flat below 4,000rpm

I'm after swinging to 8500 RPM but on a 3L...

Also, people say it's "in the lift and duration" how? do they lift less but have an uber long duration or something? I want to know that if you ran a 256degree Turbo cam, what the difference is to a 256 NA cam...

I'm running ITB's on an RB20DE in my rallycar. Still a 2ltr for class requirements.

I don't have the exact spec of the cam's on hand, but they are 280° duration and max lift we could run with the standard lifters/followers. The head has also had a lot of porting done, although I feel we may have gone a little too far on the port size and cams. It pulls strong for a 2ltr, but is very fussy on intake length adjustment and doesn't have the torque I'm looking for yet.

Cams are a custom grind made by Kelford Cams, as no one really has any spec's on ITB N/A RB motors. I would say the 2.5ltr will be easier to strike the right tune with the cams thanks to the extra capacity. To me it sounds like you are after peak hp and rpm? I'm after the opposite, however the 'lil bugger does like to rev to 8,500rpm all day long on the stock bottom end. Oh and the sound!! :)

Vids' FYI

-motor is too flat below 4,000rpm

Sweet mate!

I'm a torque hunter like yourself bud :)

I wouldn't mind upping the hp abit tho, 300bhp would be nice.

The car's going in again in 2 weeks for a shift light function wiring in that can be used with the K3.

It should hopefully see some more hp, the garage has said possibly between 30 - 45bhp depending on how much they can fine tune it which they are fairly confident in.

Here's a vid of how she sound's!

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