RB26 camshafts in RB20??

[DVS JEZ]

I've been told by the bloke who worked on my head that upon removing the cams you must bleed the lifters as they can pump up slightly.

If the lifters have pumped up slightly and you install new cams it will cause the valve to open slightly and possibly kiss the piston resulting in a stuffed valve.

On that note, he didn't mention it BUT I have read here and there that to get around this problem some have spun their motors 10degree's off TDC, installed the cams and its all been good.

So becareful.

Those interested...

I think the cheapest way out of an aftermarket set of cams is to grab a set of GTR cams, send them off to LukeVL (from calaisturbo.com who works for or owns, Tighe Cams in QLD) and have them reground to your requirements.

i wish this was mentioned about 2 weeks ago...... DAMMIT.

would have saved me some money

[r3240sx]

i wish this was mentioned about 2 weeks ago...... DAMMIT.

would have saved me some money

Just got my car back together and running. Cams work fine, I dont see the big fuss.. Really just gotta take your time and make sure the cam caps/journals are smooth, and the cams arent bent. Most time consuming part was finely sanding the bolts to fit better in the cam caps.

Worst idle EVER! I've heard cammed LS1's idle better than this!! If I knew the idle was going to be this bad I would have gladly paid DOUBLE for the cams even if they didnt make any more power! Sounds like a drag supra! Its the truth, the sound is the real gain! Now, when I time the car properly, fix my humungous boost leak, and adjust the idle a little, I'm convinced the that idle is just going to be a little rougher than stock... but seriously dudes, you're modding a car for higher HP (kw's, whatever..), sacrifices must be made.

I'll post my power gain impression once I work out these few issues.. I'm still convinced I described the important part of the payoff of these cams though (sounds).

Great thread guys, a few bits of info in here really helped..

Thanks Dudes!

-Max

[Cubes]

Take note of fuel consumption if you can.

Yes they are a performance car but if it sucks another 100km's less per tank when cruising around for another 10-15rwkw when stuck up it the we know its not really worth it.

[R31 POWER]

r3240sx what model GTR are your cams out of? What cam caps did you use?

Thanks.

[Adriano]

Have you driven it yet? The car i tried it on, we got it to idle(lumpy) but the car lost about 50% of its torque up to 3-4000rpm, didnt bother revving it any harder

[r3240sx]

Have you driven it yet? The car i tried it on, we got it to idle(lumpy) but the car lost about 50% of its torque up to 3-4000rpm, didnt bother revving it any harder

I used rb20 cam caps.

I have only driven it slowly.. but I did get on it in first, twice, which broke the tires loose about 4000 rpm. I havent timed the car yet and I left a BOV unplugged, so I've got 2 huge problems that are sucking power..

Yes my car has basically no torque now.. I dont see how people do any cam upgrade in an rb20 and get this bad of low end.. I dont buy it just yet, I'm gonna fix my boost leak and time the car properly and then give you an accurate power opinion.

[r3240sx]

I used rb20 cam caps.

I have only driven it slowly.. but I did get on it in first, twice, which broke the tires loose about 4000 rpm. I havent timed the car yet and I left a BOV unplugged, so I've got 2 huge problems that are sucking power..

Yes my car has basically no torque now.. I dont see how people do any cam upgrade in an rb20 and get this bad of low end.. I dont buy it just yet, I'm gonna fix my boost leak and time the car properly and then give you an accurate power opinion.

r33 rb26 cams btw

[r3240sx]

what should I set my timing at?

RB20 timing (15) or

RB26 timing (20)

Idle Vid:

Edited January 16, 2007 by r3240sx

[R31 POWER]

I think you need another muffler

[ROB32T]

sounds tops

[Jago]

doesn't sound clear enough for me to decide whether it sounds good or completely shit

[r3240sx]

Lol, that exhaust is a 3.5" from the turbo elbow back.. Its still to quiet! The Nur spec can's sound deadening is completely gone too...

I like cam idles, so it sounds cool to me... but yeah, unhealthy at the same time.

[Jago]

Lol, that exhaust is a 3.5" from the turbo elbow back.. Its still to quiet! The Nur spec can's sound deadening is completely gone too...

I like cam idles, so it sounds cool to me... but yeah, unhealthy at the same time.

It's just this "howl" sound that kinda makes me a bit iffy/makes it a bit hard to hear. Mine is obscenely loud (well, almost), so maybe that'd make all the difference

Anyway, i might actually seriously look into this, not for the sound, but for the "mild" performance gains (for the meantime, untill i get a serious engine build going).

I dunno, but surely a sound like that can't be that healthy with such "minimalistic" cam profiles? When you look at the specs it's really nothing huge. Have you managed to check everything out yet?

I mean, i was expecting a lumpy idle, just not one of a high lift and duration equipped drag car. Kinda sounds like it doesn't know if it wants to die or keep running. I dunno, still very hard to hear as it's not very clear.

[Roy]

Forget how it sounds...how does it drive? Is it a gutless pig down low, more so then std?

[Jago]

ya give us an update

[r3240sx]

ya give us an update

Moved away for school, ran out of money... Put the stockers back in.

I found out the lobe center angle is slightly off of the stock rb20 cam specs.. thus the massive overlap, horrible idle, and not much top end.

If I didnt run out of money for cam gears I would have continued.. Cams are on the shelf untill I come across a few hundred $$.

I dont want anyone to become discouraged about this swap, I'm still supporting the fact that its a very worthwhile upgrade. The second time I swapped cams I did it in about 1/5 the time.. Its easy, just use common sense...

...and get cam gears!

[Warpspeed]

Sure, it is a very worthwhile upgrade.

That is, if your only aim is a lumpy unstable idle, loss of low end torque, diminished fuel economy, and about 1/2 a Kw improvement at the extreme top end.

But hey, if you guys only want a hot SOUNDING engine, instead of something that is actually more powerful, and you are having fun, go for it...

[r3240sx]

Sure, it is a very worthwhile upgrade.

That is, if your only aim is a lumpy unstable idle, loss of low end torque, diminished fuel economy, and about 1/2 a Kw improvement at the extreme top end.

But hey, if you guys only want a hot SOUNDING engine, instead of something that is actually more powerful, and you are having fun, go for it...

Funny joke, If you want to try to act smart next time, you could read my post and maybe understand what I said. Have you ever driven a car with messed up cam timing, of course its slow.. The rb26 cam lobe centers arent even the same degree as stock. Put a set of cam gears on it and set the timing, even to stock.. and if you dont think .7 mm higher lift and 8 degree longer duration is a worthwhile upgrade... well then you're retarded

[Cubes]

So your disregarding the problem has anything to do with the ramp rate?

'Hydraulic' cams run a less aggressive ramp rate than 'solid' cams for a very good reason.

[GTRgeoff]

Geezus Max, Warpspeed has probably forgotten more then you hope to know. He isn't being funny, just very matter of fact.

I've done this in an RB25DET and the result was total pox until the rpm hit 4500+, then it lit right up and for a car that was fairly dedicated for track, but still road driven it was still too much compromise.

At the end of the day the problem is and always returns to the fact that the cams' ramp angles are not ground correctly for hydraulic lifters. This results in early cracking of the valve seal and loss of compression regardless of lobe angles.

But then some of us here have so little experience that we must be completely without a clue.