Page 1 of 1

gt engine tunning tricks

Posted: Tue May 11, 2004 6:24 pm
by wanstall
hi guy

i was just woundering if any of you know how to get the most out of the 1.3 gt engine. other that the usual filter, and exhaust.

i have heard that fitting twin webbers will increase performance?
what about cams?

cheers

Posted: Tue May 11, 2004 6:55 pm
by hardhitter
Theres loads of things you can do to make the most of a gt engine. Heres a run down of the things I can think of, from the top of my head:

Filter is a good one, either panel filter in modified air box or an induction kit with a heatshield (which I'm currently making).

Exhaust is another, usually a 2" diameter system with de-cat is pretty damn good.

Ecu chip (which I do again) will perk things up and smooth the acceleration and generally improve drivability.

Golf/Jetta/Passat Digifant igntion coil setup is another good idea.

Extra earth lead to lambda probe.

Block the oil breather from going into the inlet pipe.

A modified throttle body makes an improvement as I have recently discovered.

After that it might be worth looking at porting the head and maybe a fast road cam, these need careful choosing though.

Twin webers are very troublesome in my experience, I helped a chap do this conversion on his gt and it's a lot of trouble.
The carbs would need constant attention and tuning. I wouldn't advise them.

Hope this covers enough for you. :D

Posted: Wed May 12, 2004 2:24 pm
by Krupa
hardhitter wrote:Block the oil breather from going into the inlet pipe.
Hmm, how do you do this, and what does it do? :?:

Posted: Wed May 12, 2004 4:44 pm
by Tahrey1043
grab a haynes, find out where the breather goes into the intake, and pull it off :D

though if you're going to do that you may as well remove the whole thing IMHO

Posted: Wed May 12, 2004 5:39 pm
by Krupa
Tahrey1043 wrote:grab a haynes, find out where the breather goes into the intake, and pull it off :D
What about sealing the holes up?

Posted: Wed May 12, 2004 5:39 pm
by Gareth_GT_Hatch
Dont do that cos that will totally screw ur engine up. You need to put something in the hole that you leave when u oull out the pipe so you dont suck loads of crap into your intake system

Posted: Wed May 12, 2004 5:41 pm
by Gareth_GT_Hatch
Its the pipe just to the left of the throttle body on your intake pipe. You need to put this pipe into a catch tank.

Posted: Wed May 12, 2004 5:48 pm
by wanstall
cool thanks for the advice.

what did you do tho your throttle bodys?

will set right to work.

Posted: Wed May 12, 2004 6:26 pm
by hardhitter
You remove the rubber oil breather hose that goes into the inlet elbow.

The hole needs to be blocked up, I have some some plastic plugs to do this, I will try and get a pic of what it looks like. Then it can be vented to atmosphere or a catch tank. You can make a catch tank from a plastic bottle if you cant afford to buy an alloy one.

The benefits of doing this mean you arent burning oil vapour which would normally lower your octane rating. Also you don't get any oil deposits which tend to gunk up your inlet pipe, throttle body and inlet manifold etc over time.

A cheap mod which is definately worth doing :D

I need to start doing some faq's

Posted: Wed May 12, 2004 8:04 pm
by amstrange1
The breather mod is definately worth doing. Back in the day when I ran a CL engine on GT injection I used to have all sorts of breather problems - once I'd taken it all apart, cleaned it up and vented the breather to a bike bottle catch tank it was fine. Ran a bit smoother too. I haven't bothered to do the breather mod to my current GT engine as it's only supposed to be a temporary measure 'til I get my G40 back.

Oh, another possible mod is to use a G40 exhaust manifold and downpipe - it helps top end on my GT setup. Either that or a 4-branch exhaust manifold - I think Dan might be looking in to supplying these.