1.8 engine performance upgrades?

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SciRossco
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1.8 engine performance upgrades?

Post by SciRossco » Tue May 17, 2016 8:44 pm

Well the old boy is out for the summer again so I've decided to focus on getting some extra performance with keeping the original 1.8 8v carbed engine

Just fitted the jetex single 2.5bore exhaust and what a difference sounds and looks great but thinking now about an induction kit (which I can't find for this engine??) and the possibility of upgrading the carbs to twin Weber any advice would be much appreciated I've been looking on the net and there's not a lot there to bet.onest!

SciRossco
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Re: 1.8 engine performance upgrades?

Post by SciRossco » Fri May 20, 2016 2:42 pm

Btw is it easy enough to fit the scala fuel injection to a gt2?

Old Mac Rocco
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Re: 1.8 engine performance upgrades?

Post by Old Mac Rocco » Sat May 21, 2016 8:33 pm

The best man I can recommend this far north is bengould on the register.
Unfortunately my knowledge is limited but Ben has engines out and back in on the same day without getting a sweat.
He may be at Biggar but I haven't heard much about the shows this year.
I drive a 1987 Mk 11 Scirocco GT 1.6 Carb - daily driver.

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Re: 1.8 engine performance upgrades?

Post by bengould » Tue May 24, 2016 10:58 pm

Fuel injection is a no go unless you change the head, the injectors dont go into the manifold like a "normal" engine.

Four branch manifold will compliment rest of the system well, but the 6 bolt manifold is also said to flow much better that the toilet bowl affair fitted to scirocco. Possibly available a bit cheaper than a manifold.

Upgraded cam will give you a decent gain. I have one sat in a spare engine if you're interested. ;-)

Twin carbs will give you good power but can be a bit of a pig to fit because they point to the scuttle panel instead of the radiator.
Bike carbs tend to be a bit smaller than twin webbers etc so a bit easier to get fitted.

You won't find an induction kit, they don't make one.
A panel filter in the standard air box will be fine, but if you go down the twin/bike carb route you won't be able to use it anyway so decide first rather than buying it to then not need it.

I will be at Biggar all weekend, feel free to say hi and have a chat. We normally camp near the entrance, will be in a candy red Corrado and bright pink Beetle this year. You can't really miss us. :-).

Ben.

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Brunty
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Re: 1.8 engine performance upgrades?

Post by Brunty » Sun Jun 05, 2016 12:49 pm

Weber 40s on the 8v engine look like this.

Image

You can still get decent power, but they can be a bit of a squeeze. Still better than bike carbs though (I'm not a fan of bike carbs, they belong on small engines that have a lot of flow).

You can pick up cheap 4 branch manifolds now - have a look on ebay. The designs all look basically the same and are clearly based on Supersprint, but a fraction of the cost. I've used a couple and they seem absolutely fine.

On the 90bhp carb'd engine you can fit a fast road cam, 4 branch (4-2-1, rather than 4 in to 1), exhaust and the Weber dmtl carb and end up with approx 110bhp. With a ported & port matched head and Weber 40s you'll be looking at about 130bhp.
Brunty

Image

SciRossco
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Re: 1.8 engine performance upgrades?

Post by SciRossco » Sun Jun 05, 2016 10:38 pm

Had a look on ebay looks like I'd need to put about a grand into it for all that lol

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Re: 1.8 engine performance upgrades?

Post by CARiD » Thu Jun 30, 2016 10:11 am

You can make a custom air intake with a drop-in filter like K&N. You would need a hose that connects to the the TB and matching size cone filter that attaches with a help of clamps. It should let your engine breath in easier and result in a better throttle response.

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Re: 1.8 engine performance upgrades?

Post by bengould » Mon Jul 04, 2016 6:55 pm

That's about right. And for not a massive amount more money you could get close to 200bhp from a 20vt conversion, if your willing to do the work yourself.

Ben.

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