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Discussion Starter #81
What lift cam does the rb kit come with rich?
Not sure Dan, I think they are doing a few different options, best to speak to them I wouldn't want to mislead you. Rod did say that the kit included an Inlet Cam though.

Does this system need the same type of Pistons (I think the top is different) as the v-can type 2 and pro, or can you have normal type Pistons?
Not sure mate, you would have to ask him, but he didn't mention different pistons being needed.

:)
 

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Did anyone get any more info on RB's V-Cam ?
Seems no one has any real evidence one way or another.

I know some blokes have used V Cam and love them, but why not show us something and tell us what the cam was before the V Cam was installed and what cam has come with the system.

There are no back to back Dynos to look at that I could find, well that would be better than nothing.
Have not even seen figures showing the gains before and after with the V Cam. well except for HKS ads?

If you are happy with your cams, can your cam be modified to use with the V-Cam system or do you" have to" use the cam that comes with the HKS system ?
So many questions, because I do not know the answers, lol :chuckle:
 

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Discussion Starter #86
Did anyone get any more info on RB's V-Cam ?
I am sure Rob at RB will be able to give you all the information you require.

"Evidence" as such is fairly obvious as pretty much all modern engines use some form of variable valve timing.

As for examples on RB's, it can all be backed up I am sure - most people probably don't shout about it as not many of us can afford £2k for an inlet cam system!:runaway:
 

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From what I could find out, there is a problem using a higher lift cam than used with the V-Cam Pro, there is a valve to piston clearance problem with the big change in timing , but ?
 

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RM Motorsport V-Cam

All

My car (R32 GTR) is booked in with RB Motorsport next week for a few jobs including the fitment of their V-Cam setup.

Whilst I haven't had my car on a dyno, it was mapped and dynoed at MGT Racing nearly 2 years ago and she has done very little mileage (<1,000 miles) since.

She is running:

R33 GTR engine (fully stock rebuilt),
Vipec i88 ecu,
Boost control kit,
Closed loop lambda
Closed loop knock control,
Garrett GT2860-7s BB turbos,
Full HKS metal gasket kit including head gasket,
Nismo 555cc injectors,
Uprated fuel pump,
Greddy 8s Plugs,
Splitfire Coilpacks,
Tomei PONCAMs Type A,
HKS Vernier Pulleys,

In the above spec she made 484bhp at the hubs (at MGT) at 1.2 bar boost and is very driveable.

MGT are about 2 hours drive from me but (in the interests of science) I may take a trip down to them to get my car dynoed again after the V-Cam installation.

This should give a good (different days but same dyno) back to back test and allow me to overlay the dyno graphs to get an "on paper" comparison.

Obviously this is only "on paper" and for me the real result is how the car drives. Rod took me out in an R33 with a similar spec engine to mine (including -7's) but running their V-Cam system and it was SOOOOOOOOOOOO smooth that I ordered mine on the spot!

My car is not a qtr mile monster or track beast so I am not chasing numbers but want my RB26 to run like a modern day engine, V-Cam brings it bang up to date and goes a long way to achieving this.

I should have my car back in a couple of weeks so will report back then.
 

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All

My car (R32 GTR) is booked in with RB Motorsport next week for a few jobs including the fitment of their V-Cam setup.

Whilst I haven't had my car on a dyno, it was mapped and dynoed at MGT Racing nearly 2 years ago and she has done very little mileage (<1,000 miles) since.

She is running:

R33 GTR engine (fully stock rebuilt),
Vipec i88 ecu,
Boost control kit,
Closed loop lambda
Closed loop knock control,
Garrett GT2860-7s BB turbos,
Full HKS metal gasket kit including head gasket,
Nismo 555cc injectors,
Uprated fuel pump,
Greddy 8s Plugs,
Splitfire Coilpacks,
Tomei PONCAMs Type A,
HKS Vernier Pulleys,

In the above spec she made 484bhp at the hubs (at MGT) at 1.2 bar boost and is very driveable.

MGT are about 2 hours drive from me but (in the interests of science) I may take a trip down to them to get my car dynoed again after the V-Cam installation.

This should give a good (different days but same dyno) back to back test and allow me to overlay the dyno graphs to get an "on paper" comparison.

Obviously this is only "on paper" and for me the real result is how the car drives. Rod took me out in an R33 with a similar spec engine to mine (including -7's) but running their V-Cam system and it was SOOOOOOOOOOOO smooth that I ordered mine on the spot!

My car is not a qtr mile monster or track beast so I am not chasing numbers but want my RB26 to run like a modern day engine, V-Cam brings it bang up to date and goes a long way to achieving this.

I should have my car back in a couple of weeks so will report back then.
Been in something similar with a BW EFR 8374 on it, magic :bowdown1:
 

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RM Motorsport V-Cam

Moleman

Depending on your engine spec, ECU and what other work you are having done (could save some labour costs) you are looking at around the £4k mark supplied, fully fitted (a 15-16 hour job) and custom mapped to suit.

The kit comes with a brand new inlet cam so you may be able to recoup a few £ buy selling your old one (assuming it is not standard).
 

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RB Motorsport V-Cam

All

My car is almost ready for collection and is only now awaiting a replacement air con compressor (original one is leaking) but the mechanical work and mapping is done so I took her out for a 10 minute blast yesterday when I called over to RB Motorsport.

Will have to wait until I get her back on a dyno to prove "on paper" difference but the real world difference is unreal!

The WAS - Old set up was standard static inlet cam timing (ie not V-Cam) running 1.3bar boost. As always these things are a compromise on cam timing to achieve 1) an acceptable idle, 2) build boost a quickly as possible and 3) make good power at the top end of the rev range. BUT you cant have all 3!

Before the V-Cam was installed my car ticked over reasonably well - the normal cammy RB26 tick over with a bit of hunting and tappet noise.

She used to build decent boost from about 3,700 rpm and pull strongly through the mid range but run out of lungs above 7,000rpm.


The NOW - new set up with RBM V-Cam running less boost (1.25bar v 1.3bar) and 2 switch over points is night and day difference.

Tick over now sounds like a Lexus compared to the old set up and she just sits there purring away down to the fact that the cam timing at this point is running pretty much as stock.

Apparently the V-Cam then advances the inlet cam timing from around 1,900rpm to promote much improved inlet gas velocity which gets the turbo's spinning MUCH earlier than before so boost builds more strongly and a lot earlier.

You can REALLY feel this from the drivers seat!

Now that the turbos are really into their stride the V-Cam system then kicks in again at just under 5,000rpm by retarding the timing which gives optimum inlet cam timing for producing big top end power. This again can be felt from the drivers seat as the car feels like it comes "on cam" and literally rips through to its' rev limiter (mine is set at 7,900rpm).

The dyno will ultimately prove whether she is making more "peak" BHP than before (don't forget I now run less boost at 1.25bar v 1.3bar) but from the drivers seat there is no question - the new set up monsters the old one!

I am quite geeky when it comes to how the combustion cycle works and (after talking with Rod Bell) the reasoning for this improved top end performance is actually quite simple:

With static inlet valve timing on an RB26 you have to compromise so you need some advance to spool the turbos up on to boost but this is not ideal for the higher rpm range as this generates too much valve overlap which contaminates the inlet charge and also effectively reduces the compression ratio. You can try to counter this by upping the boost a little but you will never achieve an ideal combustion cycle under these conditions.

The V-Cam in basic terms gives you 3 engines in 1:

1) A nice unstressed lump that will tick over like stock due to the soft cam timing
2) On the first timing switch you get a torque monster that gets the turbos spooling hard and early
3) Final stage is a very rev hungry unit that makes strong power through operating a very efficient combustion cycle in the upper rev range

You pays your money and makes your choice - just my 2p worth!
 

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VERY interesting!

I have to say that the old car I had with V-Cam I really took for granted as now I realise a small twin RB26 without it does feel a little flat in comparison.

My car will be with Rod & Co as soon as I cant get a slot after getting it back.....will defo have a chat about this.

I wonder what it would be like in combination with a small EFR, 6 speed getrag and lower final drive :cool:
 

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I put the V-cam on my 3.2 stroker R34GTR , it is so linear now you have to look at the speedo because it feels slow, but then you know it is pretty quick, lol

With the EFR8374 it runs out of puff and could do with the 9180/1.45 a/r but I like the way it drives for a street car and will stay with this setup
 

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I put the V-cam on my 3.2 stroker R34GTR , it is so linear now you have to look at the speedo because it feels slow, but then you know it is pretty quick, lol
Nice curve! Out of curiosity, is that with a Step 2 or Step Pro? I'm torn between the two for a 3.4 9180 QSV build. I wouldn't want to overdo lift to maintain piston clearance with 9+ compression but not choke the engine either. Big valve ported head so it might do ok with a milder cam.
 

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Nice curve! Out of curiosity, is that with a Step 2 or Step Pro? I'm torn between the two for a 3.4 9180 QSV build. I wouldn't want to overdo lift to maintain piston clearance with 9+ compression but not choke the engine either. Big valve ported head so it might do ok with a milder cam.
Its a step 2 , I think I would have been better with the step pro , but as I wanted response I thought the Step 2 would be better.

CR is stock at 8.5 and no Port or polish but that's what I would do if I wanted a bit more up top and let it breath , if I upped the CR 9.5 ish , I think the response would still be similar to what it is now, but an expensive mod .

Looking into it but do not want to be waiting around for months , the car is mad as it is for the street :)
 
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