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Heres a picture of my hydraulic head MH engine!, Would I have to change the head with an earlier model? to achieve 75 bhp. Also has anyone cammed there engine or has a cam they want to sell? [img][img]http://img.photobucket.com/albums/v308/ ... C_0319.jpg[/img][/img]

GK engines are like hens teeth Id imagine. The MH head is (As far as I know) the same casting as all 1.3 heads (including the G40) So the head isnt the problem. A better cam (such as a GT cam or an after market one is the way to go. As well as a better carb like that one overmind is selling. And seeing as youve already properly sorted your exhaust system (judging by your list on the other topic) thats all youll need to achieve 75bhp I bet. Oh and there is a manifold on the mk3 1.3/1.4 Spi that might be of use to you (I think it has bigger ports) I have one somewhere but Ive never compared it to the one on my mk2

Hmm. I assume sticking a GT cam in a 1043 would do more harm than good? Roll on the day that I can be bothered / can afford to stick a 1.3 in mine..

Gareth gt- ive already got an ashely 4-2-1 manifold, surely nothing can be better than that? anyway thanks for the advice and also would a gt cam make the diference??

yeah thats what I meant, you dont need any more exhaust mods, just a better carb and a cam.

GC, Im not sure if the MH cam is any better than a HZ one. You would need to have them both side by side to examine lift/duration. A GT cam is definately better than both though.

bear in mid that if you mk2'ers buy a cam that was designed for a mk3 you will have to sort out an electric fuel pump as mk2 camshafts drive the fuel pump whereas mk3s have electric fuel pumps as standard.

Yeah, I was mulling this over earlier, realised that a carburetted mk2 75bhp gt like the one at the start of this post will have an old type head with the mechanical pump on the other side, and a fuel injected mk2/3 gt will have an electronic pump.. although, it may be something I consider later, I was thinking about adapting a mk3 fuel injection system anyway... it'll go on a back burner for now though

yeah Ive been contemplating converting to spi as well. I almost have all the bits, (apart from the loom, ecu, injector, and fuel pump) Oh well maybe I dont have most of it then. I have all the fuel lines though. and the lift pump But wiring all that stuff in would be a bit of a nightmare. Its less difficult on our cars as wever just snuck in under the wave of revisions. so theres brackets for fuel pumps and the ecu and the like...

Can't see it being too much of a problem.. although I'd choose a time when I didn't need the car for a couple of days before I went ahead and did it

Just realised I'd have to find a way to plug the fuel pump driveshaft hole in the cylinder head.. that damn fuel pump seems to cause all the problems I assume the SPI wouldn't work properly without the electric pumps?

id just leave the fuel pump on. No worries about hole plugging then! I doubt the spi would work off a mechanical pump as it doesnt pump at high enough pressure.

Youd also need a mk3 exhaust to fit the lambda probe. Something which slipped my mind before. But I have a spare one of those as well (or I will have on thurs when I get my complete barningfield exhaust. )

if you could do the same upgrades on a 1.0 as you could a 1.3, with like-for-like proportional improvements, you'd see about 60 horse by the end of the day - worth considering if you can't find a 1.3 but have the other things handy...?

(plus the 1.0 should be more rev-happy ... oversquare chamber shape )

As far as the exhaust goes I think I'd probably just cut a hole in mine and get someone to weld a nut to it for the probe to thread into.. un-environmentally friendly as the decat pipe may be, I don't terribly want to strangle the 45bhp any further with a cat

1.0 more rev happy? How do you figure that one? I've always assumed it to be less rev happy than the redline on the coupe s clocks tells me just trying to be safe and not blow it up.. more rev happy could be interesting Although, the power really falls off after about 5,000 rpm anyway..

shorter stroke of the 1043 means they can go round that bit quicker. But the AAU engine is an awful engine to try and modify, has smaller valves and ports than all the other engines, 1.0 mk2s have the same head/valves/ports as 1.3s so im told (steve has one on his 90bhp mk1)

Decat mod of a mk3 pipe only costs about £35.

Ah, but a drill, a nut and a friend with welding kit costs 20p and a pint for his trouble Student financial logic comes heavily into play in such matters

So.. what would I need:
* Inlet manifold, tb etc
* Electric fuel pump (two of them, aren't there?)
* ECU
* Wiring loom
* Downpipe / lambda probe

What have I missed? I've never delved into anything so sophisticated as electronic injection, I've only just got a handle on carburettors, so I know very little about all this stuff..

i think thats it unless you need the fuel tank as well (you should change it but its possible to get away with it i think.) I have one of those spare as well!

Oh youll need the exhaust manifold as well probably as i think the older cars join to the downpipe in a different way.

Mine joins a single downpipe with a clamp that wraps around the two.. that's different to the mk3 isn't it? Think the early 1.3's had the same twin downpipe though?

Think I'll just raid the next mk3 that comes into the local scrappy, see what's different about it..