Was 240, Now 225 With Cams?

[Cubes]

GCG highflow maxxing out at 250rwkw ehh? Are you sure on this claim?

Abo Bob is running one and he's pushing (well was) 255rwkw on 0.9bar of boost + Tomei Type B 260degree Poncams. I really doubt that the turbo had run out of puff by then.

There comes a point where dialing in more boost only induces detonation and the amount of ign retard required for it not to detonate doesn't increase power.

The GCG highflows are running the std turbine housing and std comp cover. 450bhp ~260rwkw is a damn good effort taking that in to consideration.

Better fuel.. No doubt you can make more power, on pump fuel it appears unlikely.

[The Dan]

The GTR's work best usually on 4° retard ex and up to 6° advance in. But as Nismoid said, yours is not a 26 and you should always start from zero. 20's are usually good on 4° retard ex and 0° in and 25's 0° all round.

[Al]

When i first installed the Tomei poncam, my mechanic and an aircraft engineer did some calculations and ended up using 2deg on the ex. cam. After a few weeks i went back and insisted to set it back to 0deg, as a test. My reasoning; as an aftermarket cam they would be designed to perform at their best at zero degrees (ie: no adjustable cams required). He set it to zero and retuned the car, ending up with an over-all improvement across the whole rev range.

Hence why i asked the intial question

[tridentt150v]

Just to let everyone who helped me know.......

Because I work for a living, couldn't do anything till the weekend.

I've just reset the timing on my exhaust cam wheel to 0 degrees and then reset my ignition timing at 10 degrees and took the car for a quick squirt..............noticable power plus boost spiking to 1.5 bar [peaking at 0.85 before, so almost double, I'll have to reset my evc etc now]. I'll be taking it back to the dyno this week sometime and getting the power fc map set up to suit the changes [and while I'm at it I'll have to convince the mechanic that I used that -5 degrees is NOT for RB25's, and hope he learns from this as I have].

Thanks all!!!

PS Don't panic, it was only a very quick short squirt in 3rd gear on a very short [private] road, so the 1.5 bar spike couldn't be held because I ran out of road and hill. But its all very promising.

[Al]

Keep us posted

[GTshortie]

Tridentt did you ever sort out the camshafts timing issue and gained more power?

[jnr32r]

definetly set them at 0 both in and ex....

[tridentt150v]

God this is an old old old thread, I'm way over that, but..........I really haven't tackled it either. I got an offer for the turbo that I couldn't refuse, I've now got a Hks cast low mount at UAS being extrude honed, I brought a Garrett GT3076 WG off Slide sitting right here next to my computer, I'm about to buy a Hks 40mm external wastegate, and I'm waiting on Lincorp to send me my manifold gasket set which I've paid for [Oh and I replaced my Walbro with a Nismo fuel pump]. Doing all this at home, intend to make my own s/s dump and intake pipes although I have sort of cheated and brought a s/s 3" split dump that I intend to cut and shunt to fit my vehicle. This was about the same as buying bends and pipe etc in price and I get a head start. Once I've got it happening, I'll probably carefully drive 200km to my mechanic and get a dyno tune [i'm in the country, part of the reason for being self reliant and 100% the reason for driving 200km].

[GTshortie]

Damn... was digging up old treads with the 'search' function' looking at getting camshafts down the track..

my only concern is that i'll encounter a problem like yours and LOSE 15rwkw after installation of CAMSHAFTS..

but my setup is different because engine has been rebuild with lower compression hence i'm worried i won't get the same benefits as others with the TOMEI poncams (20rwkw midrange, 10-15rwkw up top and more torque)

[tridentt150v]

my only concern is that i'll encounter a problem like yours and LOSE 15rwkw after installation of CAMSHAFTS..

Your kiddin'..........right!! Cams are good, tune was bad.

[Kaido_RR]

umm why have you set your gain to 100%?

sound like you need to tune ur ebc alot better

[dangerman4]

a question for everyone..

you all say strongly without a doubt set your new poncams to zero...

But on a rebuilt motor that has had its head and block decked how can the cam timing possibly be correct at zero?

let alone having an aftermarket headgasket thats a different thickness.

look at it this way every tooth on your cam gears represent 15 degrees at the crank.

if you have decked both the block and the head and are still running a stock thickness head gasket, both your cams will already be retarded by about 2 degrees. you then try retarding them another 2 or 4 degrees more as you would with a gtr etc and you loose power. you then set them back to zero and live with whatever you can get from them. Why?

i have never heard of anyone on these forums openly talking about dialing in your cams properlly with a dial indicator and setting them up to within a couple of thou of perfect. again why??

now for a couple of hours work that we can do ourselves at home why dosent anyone do it?

on the tomei website they have the detail specs of what the cam should be doing at tdc etc so its not hard to set them up perfectly. why waste time on a dyno guessing where they should be when you can dial them in to were they were made to be..

[Rolls]

Because most backyard mechanics do things by trial and error and don't like calculating and getting it right first time like real engineers do.

I wasn't aiming that at anyone but it seems to be the attitude of most backyard mechanics I know.

[Adriano]

And its not easy to do when the motor is in the car with the head on. Also tomei cant say what settings will work best on every different setup, turbo, manifolds, compression, porting etc, but i agree, getting the cam to what the manufacturer says would be a good starting point.

[tridentt150v]

' date='1 Mar 2007, 05:51 PM' post='2945607']

umm why have you set your gain to 100%?

sound like you need to tune ur ebc alot better

Huh???

[tridentt150v]

a question for everyone..

you all say strongly without a doubt set your new poncams to zero...

But on a rebuilt motor that has had its head and block decked how can the cam timing possibly be correct at zero?

let alone having an aftermarket headgasket thats a different thickness.

look at it this way every tooth on your cam gears represent 15 degrees at the crank.

if you have decked both the block and the head and are still running a stock thickness head gasket, both your cams will already be retarded by about 2 degrees. you then try retarding them another 2 or 4 degrees more as you would with a gtr etc and you loose power. you then set them back to zero and live with whatever you can get from them. Why?

i have never heard of anyone on these forums openly talking about dialing in your cams properlly with a dial indicator and setting them up to within a couple of thou of perfect. again why??

now for a couple of hours work that we can do ourselves at home why dosent anyone do it?

on the tomei website they have the detail specs of what the cam should be doing at tdc etc so its not hard to set them up perfectly. why waste time on a dyno guessing where they should be when you can dial them in to were they were made to be..

If you mean me, I don't have a rebuilt motor.......................never ever said I did. Its bog stock. One day I might, but maybe I won't - who knows. All i want to do atm is get the motor happening as best I can and then get it dynoed as best as possible.

If I do, I'll take your advise on board, I've dialed in cams before, on a motorbike admittedly. Degree wheel, dial gauge etc it was no big deal then, so I reckon I could do it on a car OK, tools are likely different, variations upon a theme. But I'm not at that point in my cars evolution yet, and may never reach it.

[dangerman4]

And its not easy to do when the motor is in the car with the head on. Also tomei cant say what settings will work best on every different setup, turbo, manifolds, compression, porting etc, but i agree, getting the cam to what the manufacturer says would be a good starting point.

being a DOHC how could you possibly dial the cams in with the head off the engine?

and the turbo etc, has nothing to do with the relationship between the crank to cam timing.

if the cams are timed perfectly to the crank as they are designed to do, then they are at there optimum setting for both fuel ecconomy and power.

[rev210]

a question for everyone..

i have never heard of anyone on these forums openly talking about dialing in your cams properlly with a dial indicator and setting them up to within a couple of thou of perfect. again why??

I did