Carbed 1.6 Gti Engine

[mishu 0]

I saw the 1.9/Mi16 to carb conversion guide on the main site, but was wondering if I could convert the 1.6 GTi engine I got from a donor car to carbs, so that I could put it in my carbed 1.1 base model.

 

I'm already working on putting the front subframe/rear axle in -- if only for the choice of GTi suspensions.

 

What do you think? What kind of work/results am I looking at?

[Richie-Van-GTi 71 2 Cars]

yes it can be done and is probably a tad easier on a 1.6 lump over the MI as the dizzy assembly is already part of the lump. Id say on a good healthy engine 120bhp is a nice achievable figure and it is worth doing on a 1.1. One thing you will need to watch for is wheel clerence issues on the back end if you stick a gti rear beam on to match the front suspension set up.

[mishu 0]

120bhp.. yum

 

What do you mean by dizzy assembly though?

 

Which parts of the loom am I going to have to keep from the GTi? I'm going to strip all the electric wiring from the GTi and only keep what I have to.

 

It was suggested to me that given the 1.6's extra weight, the GTi rear beam (with it's standard setting) would make my (lighter) 1.1 actually sit higher, not lower. But I'll have to be careful at ride height anyway since I'm refurbing the torsion bar and getting new shocks, so all the settings will change anyway.

[dodsworth_gti 11]

my 1.6 is on carbs!!

[mishu 0]

Hi! I recognize the picture from the previous posts. Yours is on bike carbs, right? Or did I remember it wrong?

Some details would be highly appreciated Performance wise, drivability in traffic (low-end and midrange behaviour), fuel consumption, fuel pump, cost.. anything else noteworthy.

 

I assume it was a 1.6 GTi to start with (my case is a bit different -- I'm putting the 1.6 engine in a 1.1 base model shell), but apart from the loom I might have to modify (although mine is already carbed, so I might just get away with it), and maybe a better fuel pump, I don't see any problems... not yet, anyway.

 

From what I've been reading on the older threads, I'm now thinking of using a pair of Weber DCOE 40mm carbs, as they seem to be pretty popular. Any idea what they cost (new)?

[j-16 1]

New Webbers won't be cheap, you'll also need a manifold to fit them to the head and trumpets+filters and then pay to have them set up. The only way for this to be even vaguely good value for money is to get a cheap second hand pair and get them serviced. To be honest I think you'd be more than happy with a standard 1.6 engine in your 1.1, BIG increase in power!

 

The weight issue you mentioned will apply more to the front of the car I think - as this is where the biggest weight difference will be due to the light 1.1 engine - should work out fine thoufh if you're also swapping the engine.

[mishu 0]

For now I'll just swap the front subframe/rear beam and overhaul my current engine (and engine bay while I'm at it), since I have no idea what condition the 1.6 is in.

 

But since my car is already running on carbs, I imagine putting all the injection/ECU loom in would be a pain (and would make it even harder to switch back in case the 1.6 didn't work out).

 

I've also checked Weber prices online, and at ~$500 per unit (new) it is indeed way over budget. Guess I'm going to look at the used market then...

Edited July 29, 2006 by mishu

[Guest ashnicholls]

Im fitting a 1.6 with xu10 (big valve head) with twin weber 40's into a base model carb 1.1.

 

As far as im aware at the moment, I am just wiring the new engine into the 1.1 loom. No need for gti loom really, except for the extra dash gauges.

 

I got set of webers for £100, recon for about £20-50

 

Head matched to fit block is about £100

 

Then you need fuel pump, and other bits.

 

New Webbers won't be cheap, you'll also need a manifold to fit them to the head and trumpets+filters and then pay to have them set up. The only way for this to be even vaguely good value for money is to get a cheap second hand pair and get them serviced. To be honest I think you'd be more than happy with a standard 1.6 engine in your 1.1, BIG increase in power!

 

The weight issue you mentioned will apply more to the front of the car I think - as this is where the biggest weight difference will be due to the light 1.1 engine - should work out fine thoufh if you're also swapping the engine.

 

I would think the 1.1 engine is heavier, because its cast iron block, and similar shape gearbox.

Whereas 1.6 is aluminium.

[mishu 0]

Ah, good to know I'm not alone. You wouldn't happen to have any pics on hand, would you? Also, good to know that I don't have to patch in the 1.6 loom (except for the oil pressure gauge, etc.)

 

If I do manage to get my hands on used Webers that would be great, but for now I'd be happy getting the engine bay clean, fixinx some minor issues with the current engine, and starting to work on the 1.6 in my spare time.

 

Where's the XU10 head from? The 1.9 GTi? I'll probably keep the 1.6 standard (hopefully it is standard right now) and only change what parts I have to. That's the plan anyway...

Edited July 29, 2006 by mishu

[Guest ashnicholls]

 

XU10 is off the 306 XSi and the turbo XU engines.

 

Straight fit with a skim and matching the ports, but wont need to if you have the same manifold as i have, as it fit the XU10 head fine. Do a search for XU 10, will mean you will get more from your carbs.

[mishu 0]

I assume it's the exhaust manifold that doesn't match, since I thought you'd have to build your own inlet manifold if you go for the 2 double carb setup.

 

What bore is the original engine? How much did you skim off the head?

 

Very nice clean engine BTW, good work!

 

Sorry if I'm getting a bit annoying with all the questions, but it's great to find someone who's doing the exact thing I want to do.

[Guest ashnicholls]

Yes, I dont know anyyone else that has done it though, its just been alot of searching and hoping.

 

Whats your msn addy

 

And i can answer your questions on that

Edited July 29, 2006 by ashnicholls

[mishu 0]

Thanks, PM sent.

[Guest ashnicholls]

No exhaust manifold matches up fine.

 

The inlet manifold on the XU5/9 does not line up with the XU10 head inlet.

 

You should be able to get a manifold to suit cheap.

 

I got my carbs with the manifold for £100.

 

Engine is standard 1.6 bore, XU10 is slightly bigger bore, but the two heads still mate up, and the difference in bore does not seem to be a problem going off other peoples findings.

 

Head was skimmed i think to give 6mm chamber depth, which after roughly calculating it with syringes and oil should give me a compression of about 9.5~10:1.

 

You need to use the gti cam though as the xu10 cam is very mild. and a 1.9 gti is cam is better than a 1.6 cam as they are supposed to be harder so dont wear as much.

 

I have rebuilt the whole engine with a lightened and balanced crank/fly.

 

Because its pointless doing all of these mods if your bottom end is no good.

Edited July 29, 2006 by ashnicholls

[mishu 0]

You should be able to get a manifold to suit cheap.

 

I can probably manufacture it pretty cheap as well, since a friend of mine works in a machine shop.

 

...and the difference in bore to seem to be a problem going off other peoples findings.

 

So other people have reported problems when using the XU10 head/1.6 block combination?

 

I do plan to lighten the flywheel too. I haven't thought about doing the same to the crankshaft though. How much does your flywheel weigh now?

[Guest ashnicholls]

sorry i mean no problems, just people have different opions on whether to use the larger bore XU10 gasket or the XU9 Gasket.

 

I am using the XU9 gasket as i have a couple.

 

I cant remember, I took quite abit off, 5Kg? does that sound right?

 

The crank was only lightened. the crank fly and clutch were all balanced together, as it is pointless balancing just the fly, as the crank will then be out.

 

sorry im tired too many mistakes

Edited July 29, 2006 by ashnicholls

[mishu 0]

It's interesting as I thought the size of the bore would have to match on both the block and the head. Then again I don't know a lot about engines, so...

 

Anyway, glad to hear it's working out. Now I can't wait to get started on mine. But first I have to get it out of the donor, probably on Monday

[Guest ashnicholls]

Well it should be but its only 2mm difference i think, so 1m either side, which when you look at it with the gasket on doesnt look a huge difference. but im no expert.

[dodsworth_gti 11]

sorry i didnt reply sooner,yes mine is a bike carbs set up,but it also has a piper 285 cam and a fair bit of head work ,i never drove it with just the carbs on so i couldnt tell you what it would be like,i know that it drinks fuel like no tomorrow though but it is in need of a set up!!

 

i paid around the 700 quid make for my carbs/manifold and setting up,every one seems to think you have to change the fuel pump to put carbs on a 1.6 but i never had to and is running ok!!

 

as far as a inlet manifold goes i belive bogg bross are the best and cheapest for them!!!

[mishu 0]

I plan to keep it standard, although I might change to a piper cam (since a friend of mine is their local dealer) and keep the standard head.

 

So no new fuel pump then? Indeed, a lot of people are changing them when switching to carbs from what I've read.

 

Could you please post a few pics of the inlet manifold? I don't live in the UK, so buying from there is out for me, but I do have access to a workshop, so I can probably weld one, once I decide what it'll look like. I have an idea what it should look like, but one more version can't hurt..

 

Also, I might also make an exhaust gallery, since the one on the donor is all rusted.

Edited August 1, 2006 by mishu

[Guest ashnicholls]

Head work is a good idea to get the most out of the engine though.

 

Why open up the front (ie webers) and rear (sports exhaust) and leave the head in its present state.

 

I would like to fit a 285 cam but want to see what one would be like with drivability first, as my car will be an everyday car.

 

You will need an electric fuel pump, as the 1.1 pump will not be very good. And the injection one will be far to higher pressure and will require a pressure regulator.

 

Just look on ebay for manifolds. Or ask in the wanted section on here.

[mishu 0]

I was thinking of skipping the head work, mainly because I don't know anyone in the area qualified enough to do it... what exactly does the head work involve? You mentioned skimming the head earlier.. details please?

 

I haven't decided about the camshaft yet (standard or Pipercam), driveability and price will be the main factors.

 

I was planning to use the injection pump (as I imagined the 1.1 might be a bit weak for the job). I've read some older posts recommending the Carter 4070 pump.

 

I don't live in the UK, and we don't have eBay, so I'll probably have to make one. Like I said, I do have access to a workshop, so that might help.

[Guest ashnicholls]

Not difficult to make a manifold just alot of work by hand.

 

If you get the xu10 head all you will need to do is skim it to a chamber depth of 6mm which will give you about 10:1 compression. Ask Matt Saville at QEP he helped me (it pops in top right hand corner if you keep refreshing the page)

 

While you have got the head apart to skim it recon the head, ie relap valves and replace all of the seals and gaskets.

 

If you are making a manifold it doesnt matter what size/shape the ports are because you can just make it up to suit.

 

Only the inlet ports are different. The standard exhaust fits fine.

 

Use a 1.9 gti cam as its more likely to be in good condition, closer to orginal lift and duration than the softer 1.6 cams.

 

1.1 cam is pointless as if its the same as mine runs off the cam, which means its dependant on revs. It does not give a constant feed like an electric pump. But the injection pumps runs on too high a feed so would need a regulator, and I am not sure but im sure to use the injection pump you need to fit the tank off the gti, sounds far easier to just fit the facet/carter pump to your 1.1 tank.

 

And eBay is interational??????????

[dodsworth_gti 11]

to drive with a 285 cam on the road is ok,not much different,gear changes can be slightly rough sometimes but thats probably just me lol

 

 

 

 

 

[mishu 0]

ashnicolls: Yeah, I'll probably stick to the 1.1 tank with a new pump.

Most people on eBay won't ship to Romania, mainly for fraud related reasons.

 

dodsworth_gti: Thank you very much for the photos, great quality.