spen has done a bike carb conversion on a mk4 16v engine and thats ina yellow mk1 golf.

he made a custom inlet for it as the inlets are oval shaped on the block so it goes from oval to circular where the carbs then mount to it! i asked him few questions as i was considering it as a possible route for my car.

bogg bros would prob make you a custom inlet for about 150-200quid i would guess. carbs themselves can be had for about 30quid on ebay.

what about using a gti bottom end with the 16v head effectively making it a 1.6? or turbo it?

andy and mikey s input make for good reading!

I'd say so. We added a vacuum take-off on Yoof's ITB manifold on his GT, though that was for the brake servo. I suspect you might find that it's more consistent if you common up a take-off from all 4 inlet runners.

With mappable ignition an AFH on bike carbs would be impressive - though I think Aldon Automotive would be happy to tweak a Coupe S dizzy to give you a more suitable advance curve.

Ok.. I'll give them a bell and see if they can add them in. They can always be capped off I suppose if I decide to do something else with the ignition.

I've spoken to Aldon already and they said they would happy to give it a go in setting it all up.

spen has done a bike carb conversion on a mk4 16v engine and thats ina yellow mk1 golf.

he made a custom inlet for it as the inlets are oval shaped on the block so it goes from oval to circular where the carbs then mount to it! i asked him few questions as i was considering it as a possible route for my car.

bogg bros would prob make you a custom inlet for about 150-200quid i would guess. carbs themselves can be had for about 30quid on ebay.

what about using a gti bottom end with the 16v head effectively making it a 1.6? or turbo it?

andy and mikey s input make for good reading!

"Turbo or supercharging this engine is possible but not really cost effective , these engines are very fragile and don't hold up that well when pushed."

thats the email i got from TSR.

what about the gti bottom end on to the top of 16v? easy to do? straight swap?

On a slightly related topic...

I'm getting a manifold made up to work with my 16v and then running it on my Coupe S ignition. Is it worth getting a pipe welding in to the side of the manifold to deal with the Vacuum Advance on the Dizzy?

As Andy said, it needs to come off the 4 inlet runners and then go into a chamber (acting like a swirl pot) before going to the Dizzy for a clean signal - otherwise you run the risk of wrecking hall senders (i've managed 2 )

Though saying that, the chap with the AFH'd rally car (Heg?) didn't use the vacuum advance with his dizzy, he locked the mechanism at full advance... not sure this is ideal though, because it will have too much advance i would have thought.. i'm not sure if the extra advance given at idle will carry on, changing the curve - but that curve given may be better suited to the AFH than the standard bob weights...

i want to do this!!!

BUT i have electronic throttle..:( dont think its possible to do it..

spen has done a bike carb conversion on a mk4 16v engine and thats ina yellow mk1 golf.

he made a custom inlet for it as the inlets are oval shaped on the block so it goes from oval to circular where the carbs then mount to it! i asked him few questions as i was considering it as a possible route for my car.

bogg bros would prob make you a custom inlet for about 150-200quid i would guess. carbs themselves can be had for about 30quid on ebay.

what about using a gti bottom end with the 16v head effectively making it a 1.6? or turbo it?

andy and mikey s input make for good reading!

"Turbo or supercharging this engine is possible but not really cost effective , these engines are very fragile and don't hold up that well when pushed."

thats the email i got from TSR.

what about the gti bottom end on to the top of 16v? easy to do? straight swap?

TSR are correct, to sort the pistons and rods alone to take boost is well into 4-figures.

If I was in your position, I'd look at sticking in a 1.6 bottom end using your existing AFH head and get your Dastek tweaked again. Jez's 1.6 16v AFH made around 140bhp, and that had stock head, stock cams and wasn't remapped - so you can expect a chunk more.

Next stage after that would be throttle bodies, and I suspect they'd enable you to make at least 160bhp - probably more like 180bhp - on a 1.6 bottom end.

spen has done a bike carb conversion on a mk4 16v engine and thats ina yellow mk1 golf.

he made a custom inlet for it as the inlets are oval shaped on the block so it goes from oval to circular where the carbs then mount to it! i asked him few questions as i was considering it as a possible route for my car.

bogg bros would prob make you a custom inlet for about 150-200quid i would guess. carbs themselves can be had for about 30quid on ebay.

what about using a gti bottom end with the 16v head effectively making it a 1.6? or turbo it?

andy and mikey s input make for good reading!

"Turbo or supercharging this engine is possible but not really cost effective , these engines are very fragile and don't hold up that well when pushed."

thats the email i got from TSR.

what about the gti bottom end on to the top of 16v? easy to do? straight swap?

TSR are correct, to sort the pistons and rods alone to take boost is well into 4-figures.

If I was in your position, I'd look at sticking in a 1.6 bottom end using your existing AFH head and get your Dastek tweaked again. Jez's 1.6 16v AFH made around 140bhp, and that had stock head, stock cams and wasn't remapped - so you can expect a chunk more.

Next stage after that would be throttle bodies, and I suspect they'd enable you to make at least 160bhp - probably more like 180bhp - on a 1.6 bottom end.

thanks mate, you have a PM

The ignition advance is only there for a nice tickover.

Edited 10 February, 200917 yr by yeha

Yeha, you mean the vac? If you do, it's there for anything other than full throttle when there is a vacuum in the inlet (obviously depending on how sensitive the vacuum bottle is). Fuel gets more chance to burn increasing the efficiency of the engine and can add a bit better throttle response.

Fuel gets more chance to burn increasing the efficiency of the engine and can add a bit better throttle response.

The vacuum system pulls the ignition point back towards tdc. The bob weights are used to move the ignition away from tdc increasing the timing angle.

I'm pretty sure that is not right.... the vacuum also increases the amount of advance, so there is an advance at low load situations when the burn is slower and less power efficient. So it happens that when the revs are higher, more throttle is used = less vacuum = bob weights doing the advancing.

also another question, does the 1.6 gti fit straight onto the 1.4 16v head, and will it be the 1.4 16v gearbox and everything else i use to fit to bottom end of gti???

If I was in your position, I'd look at sticking in a 1.6 bottom end using your existing AFH head and get your Dastek tweaked again. Jez's 1.6 16v AFH made around 140bhp, and that had stock head, stock cams and wasn't remapped - so you can expect a chunk more.

Next stage after that would be throttle bodies, and I suspect they'd enable you to make at least 160bhp - probably more like 180bhp - on a 1.6 bottom end.

180BHP from a 1.6 sounds like a hell of a lot. Even with 16 valves.

112.5 BHP per litre, thats up there with turbo charged cosworth engines. Unless its turning about 8000+ rpm of course.

In some instances the vac bottle will retard the ignition timing, like on the SAAB 900 turbos. They configured the vac bottle to activate off a more variable manifold signal, which diminished as you came off the throttle/downshifting. This prevented your blowing a hole in your pistons.

Get rid of your vac/part throttle advance and you kiss good bye to any economy on a daily

Race cars have the vac advanced plate fixed because they are consistently operating in a RPM range where the bob weights are almost or full advanced

I shall admit defeat gracefully....

But I was partly right, I just hadn't taken into account the net result of the 2 system working against each other.

If I was in your position, I'd look at sticking in a 1.6 bottom end using your existing AFH head and get your Dastek tweaked again. Jez's 1.6 16v AFH made around 140bhp, and that had stock head, stock cams and wasn't remapped - so you can expect a chunk more.

Next stage after that would be throttle bodies, and I suspect they'd enable you to make at least 160bhp - probably more like 180bhp - on a 1.6 bottom end.

180BHP from a 1.6 sounds like a hell of a lot. Even with 16 valves.

112.5 BHP per litre, thats up there with turbo charged cosworth engines. Unless its turning about 8000+ rpm of course.

well my car is running 140bhp just now, so i think ill reach in the region on 180bhp with 1.6 gti bottom end and throttle bodies.

I am basically doing this to my 1.6 AEE engine. Only thing thats on my mind is the ignition etc. I hate wires with a passion and wouldn't know where to start. Also I dont have a manual choke, what do I do then? Think I need a crash course in electrics!

180BHP from a 1.6 sounds like a hell of a lot. Even with 16 valves.

112.5 BHP per litre, thats up there with turbo charged cosworth engines. Unless its turning about 8000+ rpm of course.

Over 200bhp has been done in the UK on a 1.6 AFH build using throttle bodies, though it was built for high revs. Fairly sure someone on Club Lupo got 180bhp out of their Lupo GTI running on aftermarket management and ITBs.

By modern tuning standards the output per litre of a standard Cossie engine is nothing exciting - hell, Yoof's car makes over 150bhp/litre (without nitrous) and that's only got 8 valves.

180BHP from a 1.6 sounds like a hell of a lot. Even with 16 valves.

112.5 BHP per litre, thats up there with turbo charged cosworth engines. Unless its turning about 8000+ rpm of course.

Over 200bhp has been done in the UK on a 1.6 AFH build using throttle bodies, though it was built for high revs. Fairly sure someone on Club Lupo got 180bhp out of their Lupo GTI running on aftermarket management and ITBs.

By modern tuning standards the output per litre of a standard Cossie engine is nothing exciting - hell, Yoof's car makes over 150bhp/litre (without nitrous) and that's only got 8 valves.

I know cosworths aren't that special anymore. I just think the 100hp per litre is a good yardstick.

The Honda S2000 2.0L engine makes 240(ish) BHP (NA) at 8300rpm, which is a BMEP of around 190. Quite high for a production car.

A 180BHP 1.6 16V, making its power at 8000rpm would have a BMEP of 182 (ish), so it is very do-able.

And at around 120ft/lbs of torque it sounds very, very possible.

But by this time I think you'll have moved a long way past bike carbs and vacuum dizzies.

180BHP from a 1.6 sounds like a hell of a lot. Even with 16 valves.

112.5 BHP per litre, thats up there with turbo charged cosworth engines. Unless its turning about 8000+ rpm of course.

Over 200bhp has been done in the UK on a 1.6 AFH build using throttle bodies, though it was built for high revs. Fairly sure someone on Club Lupo got 180bhp out of their Lupo GTI running on aftermarket management and ITBs.

By modern tuning standards the output per litre of a standard Cossie engine is nothing exciting - hell, Yoof's car makes over 150bhp/litre (without nitrous) and that's only got 8 valves.

I know cosworths aren't that special anymore. I just think the 100hp per litre is a good yardstick.

The Honda S2000 2.0L engine makes 240(ish) BHP (NA) at 8300rpm, which is a BMEP of around 190. Quite high for a production car.

A 180BHP 1.6 16V, making its power at 8000rpm would have a BMEP of 182 (ish), so it is very do-able.

And at around 120ft/lbs of torque it sounds very, very possible.

But by this time I think you'll have moved a long way past bike carbs and vacuum dizzies.

100bhp/litre used to be impressive, but I don't think it's got the same significance that it used to - it certainly doesn't mean that the hobbist or back street tuner can't achieve it on a normally aspirated engine - especially when they're not restricted by the same cost/volume manufacturing/noise/reliability/emissions/efficiency factors as an OEM.

Agree re: carbs and clockwork dizzies - that's why my comments were made in the context of a 1.6 16v running on ITBs with mappable management.

so does the afh head bolt straight onto a gti bottom end?? and does the 6n 16v gearbox bolt onto the gti bottom end?

cheers