JMC's G60

[Yandards 0]

the 4 branch would aid flow ,but with greater CC more time may be needed to get rid of the exhaust gasses.Your exhaust cam duration may have been optimal for your 1.8 setup but not for your 1.9.

Thus maybe you have some exhaust back pressure in the system ?

:shrug:

 

Yes but the higher power figures provided elsewhere suggest that exhaust gasses are not being left in the cylinders in any great quanitity as this would significantly reduce power output.

 

Ideally the cam should be matched to the overbored CCs but this could just be a case that your new intercooler provides more back pressure than the smaller factory item.

[JMC 0]

I've had the Golf FMIC for ages Yan, so that hasn't changed. Could be something to do with the charger rebuild I had 6 months ago tho and had forgotten about :oops: . Right I'll go back to my little hole now :nuts:

[Yandards 0]

I've had the Golf FMIC for ages Yan, so that hasn't changed. Could be something to do with the charger rebuild I had 6 months ago tho and had forgotten about :oops: . Right I'll go back to my little hole now :nuts:

 

Er, that might do it too...

 

Reading a good book on inlet and exhaust manifold design at the moment that covers the effects of gas temp etc, would recommend it to you as it is full of equations and wave form patterns etc but is enlightening; the scientific design of intake and exhaust manifolds - a bentley title but amazon usually have a copy.

[boost monkey 0]

Oooh oooh, I wanna read! :dorky:

[JMC 0]

I've had the Golf FMIC for ages Yan, so that hasn't changed. Could be something to do with the charger rebuild I had 6 months ago tho and had forgotten about :oops: . Right I'll go back to my little hole now :nuts:

 

Er, that might do it too...

 

Reading a good book on inlet and exhaust manifold design at the moment that covers the effects of gas temp etc, would recommend it to you as it is full of equations and wave form patterns etc but is enlightening; the scientific design of intake and exhaust manifolds - a bentley title but amazon usually have a copy.

 

Yeah, I know, Mr Memory here had forgotten about that... Whats the book called then Yan - the only Bentley one I can find is about £150 on Amazon, or $29.95 from Bentley - bit of a mismatch there :shrug: ??

[Toad 0]

sticky heat sink thingys of which you speak

http://www.vividracing.com/catalog/arc-cool-fin-universal-p-45047.html

 

saw an article in Turbo magazine, they used it on the charge pipe, and oil pan. cooled down intake charge close to 10C on an evo ix

 

Aluminium is much less efficient at absorbing heat (thermal conductivity) than Copper is. Copper ftw if you can get some sinks in it.

 

Don't be fooled by copper coloured sinks, they're normally aluminium anodised to look like copper :brickwall:

 

Aluminium is good though if that's all there is to offer :salute:

 

True but copper is heavy, aluminium is light and at the end of the day its all about surface area..

 

JMC, yeah thats stock intercooler cooling figures coupled with stock charger heat output figures, so a modded charger will need a bigger cooler as you would expect hotter charger exhaust temps. It is all just speculation without some hard figures though as I sure you will agree, although any form of cooling improvement, even just 5 degrees, in the charge air temp will give performance increases - its just a question of how much bang you get for your buck.

 

Hmmmm.

 

I think I might get the blow torch and solder out and try soldering some fins onto the VR sump. I reckon a few bits of channel bent to fit the sump would be interesting, plus if they're not attached *that* well then they will not cause damage to the sump if I ground out.

 

Fuel cooler would be good, I guess that is the issue with injection systems with returns running back to the tank. The tank on my dads old lorry would get warm enough to make water steam off in the winter. :?

[Yandards 0]

I've had the Golf FMIC for ages Yan, so that hasn't changed. Could be something to do with the charger rebuild I had 6 months ago tho and had forgotten about :oops: . Right I'll go back to my little hole now :nuts:

 

Er, that might do it too...

 

Reading a good book on inlet and exhaust manifold design at the moment that covers the effects of gas temp etc, would recommend it to you as it is full of equations and wave form patterns etc but is enlightening; the scientific design of intake and exhaust manifolds - a bentley title but amazon usually have a copy.

 

Yeah, I know, Mr Memory here had forgotten about that... Whats the book called then Yan - the only Bentley one I can find is about £150 on Amazon, or $29.95 from Bentley - bit of a mismatch there :shrug: ??

 

Bentley book is this one: Geeks click here

 

The one on amazon is the same one but it is a little expensive :shock: :scratch:

 

I ordered a few titles from Bentley US and they arrived in 3 days, shipping was about $50, probably quicker than you could get them in this country!!

 

Worth noting that this was written in the mid sixties but it is still relevant today I feel.

[JMC 0]

Thanks Yan, that's the one I saw on Amazon for about 10 times the cost :shock: Must see whether I can get it for less somewhere (without shipping from the US).

[Yandards 0]

Thanks Yan, that's the one I saw on Amazon for about 10 times the cost :shock: Must see whether I can get it for less somewhere (without shipping from the US).

 

Just for info there is no duty to pay on books, so its price in dollars and then shipping only.

[JMC 0]

Cheers for the info Yan - stil can't believe Amazon don't have it new (but whsmith do :shrug: ). Anyway, I digress. Finally got my 3 slat grill, and it now makes the front of the car look very different....

 

Not 100% sure (the fogs and indicators look out of place now), but it is definately better than the old 7 slat i had on there. And it will definately let more air in 8)

[dirtytorque 0]

Cheers for the info Yan - stil can't believe Amazon don't have it new (but whsmith do :shrug: ). Anyway, I digress. Finally got my 3 slat grill, and it now makes the front of the car look very different....

 

Not 100% sure (the fogs and indicators look out of place now), but it is definately better than the old 7 slat i had on there. And it will definately let more air in 8)

 

 

I hate the seven slat grill.

 

Much prefer the new look.

[junkie 0]

I think it would suit the early bonnet been dipped in the middle, possibly....

[Kevin Bacon 5]

Hmmm, not sure about that.

 

It looks like a pond reflection :D

[boost monkey 0]

Jonathan, have you done the required experiments and grill area calculations to proclaim a 3-slat outflows a 7-slat!

 

I love the 7-slat, 3 slat looks too pikey imo... but in the name of science, it may have to be used :salute:

[JMC 0]

Hmmm, not sure about that.

 

It looks like a pond reflection :D

 

That was my thought exactly Kev :lol: looks like it has just stuck it's head out of the water....

[JMC 0]

Jonathan, have you done the required experiments and grill area calculations to proclaim a 3-slat outflows a 7-slat!

 

Nope, but I am willing to go with gut feeling on this one. The old 7 slat was only open for about half of its surface area, and the gaps were small. The 3 slat has much wider gaps, and much less solid surface area. Ergo better flow. Also and it is rather empirical, with the fan running, when I put my hand in front of the grill, I feel more air being pulled past with the 3 slat to the 7 slat. Yes, I am that sad :grin:

[boost monkey 0]

Does your hand have integrated pitot static tubes?! :lol: Fair enough buddy.

 

Jon.

 

p.s. mentioning pitot tubes makes me look like a massive :dorky:

[Yandards 0]

Does your hand have integrated pitot static tubes?! :lol: Fair enough buddy.

 

Jon.

 

p.s. mentioning pitot tubes makes me look like a massive :dorky:

 

Yes, yes it does..

 

Interesting comparison between 7 and 3 slats grills, be good to see hard numbers for suface area although there is some theory that the airspeed over the 7 slat will be faster than a 3 slat because of the greater number of slats and a venturi effect, conversly the 3 slat may provide more flow just at a lower pressure - which is more useful.

[boost monkey 0]

Goodo :grin:

 

What about with and without the VW symbol too.... Ooooh....

[Trakx 0]

Just ended reading this post.

First, congratulations on a really nice car.

Second, thanks for posting so much info.

 

Now about the diferences in boost, from your power/torque curves i think the cam timing must be tuned to horsepower, which will make peak torque go up on rpm. I have the same Pipercam 285H, which is a 268 degrees symetric cam and my peak torque is at 4500 rpm.

By the way, the best cam for the G60 seems to be the shrick 268/276. The longer exaust duration seems to help the bad exaust flow of the G60 Head. (see cncheads for flow values)

Has for the back pressure exaust consideration posted i really must desagree, since my G60 is turbo. A turbo creates much more backpressure and i haven't had problems with it and i had the Pipercam before turbo. Just haven't buy a Shrick yet because i'm afraid it will have to much overlap for a turbo engine. (Pipercam 285h overlap: 40, Shrick 268/276 overlap: 48)

 

The small diference in power seems to indicate that your old rpm head was very good.

 

Have you done anywork to manifolds to match the headwork? I'm considering buying a worked head but as i cant have no work done to the manifolds, i really don't know if it will worth it.

[JMC 0]

Thanks Trakz. Having spent quite a bit of time with Darren while this was being built, we did talk about the Schrick cam as opposed to my old Piper 285. The head has had a lot of work done to the exhaust valves, which will (fingers crossed) make up for the Piper being used. But as you say, it does make me realise how good my old head was (and how someone else got a bargain when I sold it).

 

I have not done any manifold work. It is currently running a G-Werks 4 branch exhaust manifold, and standard inlet manifold. Flusted has taken his inlet manifold apart to flow it,if you want to have a look on his gallery.

 

Just waiting for the retuned map now, so fingers crossed for that making a bit more :clap:

[rolex 0]

Retuned map done? :salute:

[JMC 0]

Retuned map done? :salute:

 

No, still waiting on Steve to rewrite the map. However I have had all the exhaust leaks fixed, and it now sounds really sweet :D . Was down at G-Werks yesterday, and a chap rolled up in a Jet for some work - never seen one of those in the flesh before (funky interior). Out of interest will repairing a very blowy exhaust affect power/torque, it's just that whenever I get my exhaust patched/holes fixed it seems more powerful :shrug: ?

[boost monkey 0]

Yeah it will affect power / torque. Some of the old 8vs (my jetta for example) wouldn't even idle when the exhaust was broken :shock:

 

Obviously yours isn't as severe, but the lack of a tuned volume of exhaust system (due to leakage) will be orvving some ponies and torques for sure.

[Yandards 0]

Retuned map done? :salute:

 

No, still waiting on Steve to rewrite the map. However I have had all the exhaust leaks fixed, and it now sounds really sweet :D . Was down at G-Werks yesterday, and a chap rolled up in a Jet for some work - never seen one of those in the flesh before (funky interior). Out of interest will repairing a very blowy exhaust affect power/torque, it's just that whenever I get my exhaust patched/holes fixed it seems more powerful :shrug: ?

 

As you have noticed in some cases exhaust leaks can rob power/torque from the engine, the same can be said for fitting an exhaust with a bore that is too big or small.