Cam Problems! Urgent Help Needed!

[muaythailuke]

Hi Guys,

Im having some real trouble with my car at the moment, its a 1993 RB25DET. Have recent rebuilt the motor with forgies, new rods, new plenum, bigger zuast and new cams etc etc... but its making less power than before, 268rwkw droped to around 230rwkw it should be making over 300

My tuner has pretty much put it down to that the cams havent been dailed in right, I wont say who put em in but what I need is the dail in sheets you get with the cams as I seem to have misplaced them.

I contacted the recommeded HKS dealer in Aus but werent very helpful and pretty much said seeing you didnt buy em through us "stiff shit" so...

The cams are HKS items 256deg\inlet 8.8 lift and 264deg\exhaust 9.0 lift.

So if ANYBODY has them or can help me could you contact me or send them through to me, all my details are below

Mob No: 0407944561

Fax: 03 63310277

Email: [email protected]

or just PM me

If anyone can help me please do as im really stuck at the moment.

Cheers,

Luke

[Craved]

have you got a picture of them with the cam gear covers off?

do they hgave ADJ cam gears with them or just using the standard ones?

have you set the bottom end to top dead centre and checked the markings on the backing plate of the cam gear covers?

[muaythailuke]

have you got a picture of them with the cam gear covers off?

do they hgave ADJ cam gears with them or just using the standard ones?

have you set the bottom end to top dead centre and checked the markings on the backing plate of the cam gear covers?

<{POST_SNAPBACK}>

Ive got an adj exh gear which is set to 0 and yep it was setup with it at TDC and all markings on backplate, gears and belt all lined up perfect but turner seem to think that with aftermarket cams they still need to be dialed in as they can be out even with this all perfect.

[Sydneykid]

Ive got an adj exh gear which is set to 0 and yep it was setup with it at TDC and all markings on backplate, gears and belt all lined up perfect but turner seem to think that with aftermarket cams they still need to be dialed in as they can be out even with this all perfect.

<{POST_SNAPBACK}>

Nope they don't, HKS cams are dialed in perfectly at the the standard markings. It doesn't matter anyway, you are going to tune the camshaft timing on the dyno using the adjustable camshaft pulleys. So setting them up perfectly first is a complete waste of time. The most common setting is 4 degrees retarde on the exhaust and 2 degrees advanced on the inlet. But every car is different.

cheers

[wrxkilla]

hi sk

what advantages does this give as a rule of thumb

as each different set of cams would require different config to get the most yes?

and by most - who wants top end who wants down low?

so what would 4 degrees retarde on the exhaust and 2 degrees advanced do?

i presume more midrange?

[Bullant47]

Sydneykid is right Luke, Your going to adjust your Exh cam using your Adjustable Cam Gear. I have the HKS Instruction sheets at home here but from memory there is only a Dial In Sheet with the HKS Exhaust Cam. If you really need the Instructions I can Scan and Email to you if you want.

Ken

[muaythailuke]

Sydneykid is right Luke, Your going to adjust your Exh cam using your Adjustable Cam Gear. I have the HKS Instruction sheets at home here but from memory there is only a Dial In Sheet with the HKS Exhaust Cam. If you really need the Instructions I can Scan and Email to you if you want.

Ken

<{POST_SNAPBACK}>

If you could Ken that would be great, it would make my tuner happy anyway, my email address is the earlier post

What he wants to know is;

What lift it should have at TDC

Crank Deg at 50thou lift

Open - Closing timing

because at the moment on both in/exh cams there is only 25thou lift at TDC an on the inlet side there is only 50thou lift 7.5deg ATDC, which he said is very out and should be more like 60-70thou lift at TDC(I think )

He said he just wants some were to start from.

The car make really good power till about 3500rpm and just not much after that.

This is all a bit over my head so sorry if i seem a bit vague, im still tryin to learn bout all this

SK - My turner said they seem to be too close and one needs to be advanced and the other retarded so ur 2deg advance on inlet and 4deg retard on exhaust sounds about right.

Cheers guys