[Mk2] [Turbo] Which Cams to get?

[Whippett]

Hi All

After some advice from you guys.

Current engine mods I have at present:

GT3071r Turbo
Link G3
Walbro 255 Fuel Pump
870cc Injectors with side feed fuel rail (Wolfkatz)
(for full mods check my garage)

Now the best time I could managed at the Pod was 13.1, which was disappointing to say the least, and then when I had it dyno'd at TDi it was only putting out around 350fwhp. I was expecting around 400fwhp. This was at 1.8bar too!! Although it did peak to 1.9bar then drop off, it's quite heavily fueling on boost, but the head just cannot flow enough air.

Now, the obvious retriction here is my head, it is totally stock. I did have it all lined up for some very extensive headwork, but then thought do I really want to be putting another £4k into this car.... the answer is now NO!

I do however want to put some cams and pulleys in RIGHT NOW! Could the pros please check out my set-up and suggest which cams would be the best to go for? I've been thinking HKS pulleys and HKS 264 low lifts to retain torque. I do not want a car that idles all horrible and lumpy like I have seen with 272s. I see that people also combine 264/272s. I'm going to bite the bullet and spend the £600 that I need to.

Cheers

[simmo490]

speak to trickster mate he is ya man for heads although allot will argue that the head is not a restriction.

oh and when ure selling ime ya man

[Whippett]

Cheers Dave, I'll send him a PM.

Don't worry mate, you'll get first refusal should that day ever come...

[EarL]

Pretty sure Graeme's head is bog standard. The stock head is fine for power levels way over 450.

EarL.

[Whippett]

So why do you think mine is way down on power?

[^Trickster^]

Hi Guys

Yeh my head is completely stock, ive never seen a setup make "noticable" difference with headwork, thats not to say porting etc isnt the way to go, but I think its more of a very high power thing.

The head flows really well for a stock head and this is evident on the amount of people running unmodified heads.

Personally I would go with normal lift 264/264 they really go well with our head, I have a 272 intake cam and its not by choice, I bought it off GTS Chris and at the time he simply had no 264 intake cams.

The benefit of 272/264 setup is you can get 10 degrees of overlap with correct timing - something I could never master unfortunantly and ended up guessing my settings from looking at other peoples timing setups!

Stock cams is definitely your restriction here, your engine just cant breathe enough, aset of cams could pick you up 50rwhp on a tuned ems and a fair amount of torque. Easy job to do aswell compared to pulling the head and having it flowed out.

Edit - What intake manifold are you running? I made 360rwhp on a stock rev 3 manifold, but the plenums are tiny and really restrictive for much over that, your money would be better invested in a manifold than headwork, itll be cheaper and see you more power!

Graeme

[splashnatz]

Edit - What intake manifold are you running? I made 360rwhp on a stock rev 3 manifold, but the plenums are tiny and really restrictive for much over that, Graeme

Do you think so ?

my car uses one of Shahids "reversed" OEM inlet manifolds and made 465ps. Pretty sure it was running out of fuelling that made Ryan stop tuning for more power there, not a mani issue.

I'm using 272's on a GT3076, no idling issues at all.

Have heard before that rev 1/ 2 inlet mani's are an issue for those seeking big power gains though (but just from interweb posts).

[^Trickster^]

Definitely, look at any real high power motors, you dont see tiny little plenums on them, you will get a much better power curve with a good inlet manifold, look at my dyno charts, with the td06 and the gt3076 my power curve is just a direct straight line, the power is really linear, unlike when i had a oem manifold. Reguardless of the peak power the actual power delivery is far better with a hig flowing manifold.

Saying that I would recommend a side feed manifold, I have a centre feed and centre feed will always favor the 2 middle cylinders, I went centre feed simply for the convienence of piping it up.

Splash you got any pics of your manifold?

Graeme

[splashnatz]

i'll sort some pics out of it tonight. Got to admit, all the cars well north of 500hp seem to have RMR's of indeterminate make Jap mani's on them.

[^Trickster^]

Big plenums make big power, my rmr manifold made a massive difference to the power delivery. Im taking it you have the plenum cut off and welded on facing backwards like i have my rmr?

Graeme

[splashnatz]

yup, you'll be able to see when i post the pics.

[RyanRs]

Graeme - are the runners on the rev3 manifold a good size? or are they also a little on the small side?? I wonder as i was intending on using some rev3 runners with a custom large tubular plenum welded on top and a side feed TB ??

Also, isn't there a rule that the bigger the plenum & the shorter the runners, the more power but LESS torque??

[^Trickster^]

I cant remember the rules on the lengths, I do know that shorter ones give a certain power, and longer ones give a different power as you say.

Also straight runners make a difference as opposed to curved.

The runners are a good size on the rev 3 and plenty of people weld large plenums to them, i think the JUN one is exactly that.

Graeme

[greeny]

Although theres a car across the pond on stock intake manifold and stock ignition running 9sec quarter miles @140+mph lol!

[RyanRs]

Although theres a car across the pond on stock intake manifold and stock ignition running 9sec quarter miles @140+mph lol!

[greeny]

Although theres a car across the pond on stock intake manifold and stock ignition running 9sec quarter miles @140+mph lol!

??

[RyanRs]

its just theres only 2 recorded 9sec passes in the states, and i never realised they using stock inlet?? i remember seeing the spec list on one of the 2 cars and im quite sure there wasnt a single standard part on or in that engine what so ever!! dont know about the other one tho...

have you any links ? interested to have a read

[Whippett]

Cheers guys!

I am currently running a stock rev2 inlet manifold and throttle body too. I was advised against the RMR manifold unless I wanted to go for BIG power. Other than the Jun, is there any more choice?

So if I went for an aftermarket manifold and some 264s, would this give me what I am looking for? Owen had the RMR on his with a Mustang 76mm (I think) throttle body and 264s and his was very peaky, but with awesome power. It didn't idle brilliantly though, especially in the cold!

I'm just disappointed with the overall performance at the moment, and whereas it is a quick car, it could be a lot quicker with a few more select mods and I don't want to be throwing thousands more at it though. A couple of £k at most.

[^Trickster^]

There are some sacrifices you have to make for power, perfect idle is one and the nature of aftermarket cams is not a great idle, but its not that bad in my opinion.

Whoever said a manifold was only for big power is talking rubbish really, getting air in and out of an engine is how you make power, the manifold is the item that delivers that air, so the better it performs, the better your engine performs.

I run a rev 3 throttle body, alot of people run ones much bigger for various reasons but I try to keep things as manitainable as possible and having a stock throttle body is always cheap and easy to replace, and they do work.

I think a rmr, jun, or another well tested manifold plus cams will give you alot more power, plain and simple.

Graeme

[jimGTS]

im running 272s aparently....(so recon ats racing)
no idle problems, sounds LOVELY to..
idle is at 1400 tho, lol.