Tu Spec, Help Needed

[Grahamrally 0]

It was just a standard TU3S dizzy Macaroni, I'm remembering now that I had to set it to about 14-16 degrees static to start it sweetly, however accelerating on that would make it pink, so I ran more like 10 degrees with a 40 maximum. It was a total nightmare to start, but once running would run great and shoot through the revs from 4500 til about 9000.

Ignition timing however is really easy to sort out, just set it at where it runs nicely at tickover, then drive it and see if it pinks. Retard slightly and try again. I always got the ignition timing spot on, because you can feel it so definately when it does change the power curve.

Hey Trogboy! Hows the project going?

[RossD 44]

It was a total nightmare to start, but once running would run great and shoot through the revs from 4500 til about 9000.

 

Blimey..... Not wonder it didnt last long

 

Just a quick question with regards the TU5 head on the TU3 bottom end, what gasket to use, would I be correct in thinking TU3 head gasket? Are there any issues with head gasket weakness using this combo?

[macaroni 17 1 Cars]

Sorry to hijack this thread, but I have some questions about timing as I find it quite a tricky area.

 

My car runs better at tickover even if I advance it as far as it will go, so if I try that and it doesn't pink, will that be OK?

 

It seems a few more people are having a go at the xs...

[RossD 44]

Sorry to hijack this thread, but I have some questions about timing as I find it quite a tricky area.

 

My car runs better at tickover even if I advance it as far as it will go, so if I try that and it doesn't pink, will that be OK?

 

It seems a few more people are having a go at the xs...

 

If it doesn't pink, I can't see a problem running it like that, I always used to run my GT more advanced than the book figure (Static Advance). The chances are it will pink though, that is unless you centrifugal advance mechanism inside the dizzy hasn't siezed and its not dynamically advancing and just sticking on the static figure......

Edited October 17, 2006 by RossD

[macaroni 17 1 Cars]

Right, I'll give it a bit more then and see how it goes.

 

My dizzy was recurved when the vacuum advance was removed and it was new only a few months ago, so I doubt the advance is seized.

Edited October 17, 2006 by macaroni

[stu_woac 1]

mine when working Lol was 10mm off full advance anymore and it would pink badly this was recurved by h&h

 

ross yes you want the tu3s gasket mate

 

with that head and throttles you will be well on your way for 120bhp maybe even just past, has the 1.6 head had work??

Edited October 17, 2006 by stu_woac

[christopher 5 1 Cars]

If anyone is interested this is the advance of the TU24 dizzy

 

[christopher 5 1 Cars]

mine when working Lol was 10mm off full advance anymore and it would pink badly this was recurved by h&h

 

ross yes you want the tu3s gasket mate

 

with that head and throttles you will be well on your way for 120bhp maybe even just past, has the 1.6 head had work??

 

 

Stu are you sure?? Won't the TU3 gasket burn out? it is 76mm and the TU5 bore is 78.5 or something. I was under the impression one would use a TU5 gasket.

 

Stu you are right...I didn't realise this was a TU3 block and a TU5 Head

Edited October 17, 2006 by christopher

[christopher 5 1 Cars]

Just a quick question with regards the TU5 head on the TU3 bottom end, what gasket to use, would I be correct in thinking TU3 head gasket? Are there any issues with head gasket weakness using this combo?

 

Someone needs to confirm here. But I was under the impression that the TU5 combustion chamber is much bigger then the TU3 one. Hence although you will have the benefit of larger valves your compression ratio (which isn't that large anyway on a TU3) will drop considerably conteracting all of the benefits of larger valves.

 

You need a hefty skim or a thinner copper gasket or different pistons

Edited October 17, 2006 by christopher

[macaroni 17 1 Cars]

Sorry to bang on about this...

 

I advance my dizzy as far as it would go and the idle is much better, as is the low speed running. There is no pre-det as far as I can tell, but it seems much less lively at the top end.

 

Confused...

[stu_woac 1]

pre ingniting now at top end

 

the head will nead a good skim or xsi pistons used

[Rippthrough 98]

Someone needs to confirm here. But I was under the impression that the TU5 combustion chamber is much bigger then the TU3 one. Hence although you will have the benefit of larger valves your compression ratio (which isn't that large anyway on a TU3) will drop considerably conteracting all of the benefits of larger valves.

 

You need a hefty skim or a thinner copper gasket or different pistons

 

 

You wouldn't happen to have any more advance curves for the TU engines would you? Might come in handy.

I think the tu5 head needed something silly like a 2+mm skim to get the compression back up to a decent level when we went through it last time didn't it?

[stu_woac 1]

yep

[macaroni 17 1 Cars]

pre ingniting now at top end

 

the head will nead a good skim or xsi pistons used

 

So I guess I should retard it again, shame as it idled really nicely.

 

The head has had 20thou off.

[Rippthrough 98]

So I guess I should retard it again, shame as it idled really nicely.

 

The head has had 20thou off.

 

Running 97 octane? As that may get you the top end back without having to retard the timing.

[Sandy 191]

Blimey..... Not wonder it didnt last long

 

Just a quick question with regards the TU5 head on the TU3 bottom end, what gasket to use, would I be correct in thinking TU3 head gasket? Are there any issues with head gasket weakness using this combo?

 

 

Someone needs to confirm here. But I was under the impression that the TU5 combustion chamber is much bigger then the TU3 one. Hence although you will have the benefit of larger valves your compression ratio (which isn't that large anyway on a TU3) will drop considerably conteracting all of the benefits of larger valves.

 

You need a hefty skim or a thinner copper gasket or different pistons

 

 

You wouldn't happen to have any more advance curves for the TU engines would you? Might come in handy.

I think the tu5 head needed something silly like a 2+mm skim to get the compression back up to a decent level when we went through it last time didn't it?

Pay attention class! I think I covered that in my first reply?

[macaroni 17 1 Cars]

Running 97 octane? As that may get you the top end back without having to retard the timing.

 

No I'm not - good point. I'll try that.

 

Anyway, I'm not gonna worry about it now, off to Cyprus tomorrow for a week!

[Rippthrough 98]

Pay attention class! I think I covered that in my first reply?

 

Didn't cover my bit !

[Sandy 191]

The only real obstacle is getting the compression ratio high enough, the chamber on that head is bigger than the earlier head, the 205 1.4 pistons are dished; so you need to skim the head and get the intruder pistons from a 1.4 XSi 105, 205 Rallye 1.3 (LHD Euro type) or pistons and rods from a 106 1.3 Rallye, milled down to fit.

How about that bit?

[RossD 44]

Just done some digging, the TU3J2 head is not just similar, its identical to the TU5J2 head, in fact they are the same part number on the Pug Parts CD. So using it on a 1360 bottom end wont be a problem as far as I can see. The fact people have done it proves this! (E.g the 106 XSi 1.4 and 1.6 heads are the same part)

 

That advance graph for the TU24, blimey its done the rounds a bit, I remember scanning that in from my french manual a couple of years back and posting it on here! I've also got the TU3S and TU3A advance graphs floating around somewhere.....

Edited October 18, 2006 by RossD

[Rippthrough 98]

Just done some digging, the TU3J2 head is not just similar, its identical to the TU5J2 head, in fact they are the same part number on the Pug Parts CD. So using it on a 1360 bottom end wont be a problem as far as I can see. The fact people have done it proves this! (E.g the 106 XSi 1.4 and 1.6 heads are the same part)

 

That advance graph for the TU24, blimey its done the rounds a bit, I remember scanning that in from my french manual a couple of years back and posting it on here! I've also got the TU3S and TU3A advance graphs floating around somewhere.....

 

 

I'd love them if you could find them for me? Anyone got any of the injection advance curves?

 

How about that bit?

I don't see any dimensions there

[RossD 44]

I'd love them if you could find them for me? Anyone got any of the injection advance curves?

I don't see any dimensions there

 

I'll see what I can do, the book is 35 miles away at the moment, will get it back at the weekend though. No, no injection curves I'm afraid, you'll have to delve into the ECU cartography for that!

[Rippthrough 98]

I'll see what I can do, the book is 35 miles away at the moment, will get it back at the weekend though. No, no injection curves I'm afraid, you'll have to delve into the ECU cartography for that!

 

 

I have a big hammer to get into the ECU but I'm not sure that'll work!

 

Do you have to stay naturally aspirated?

[RossD 44]

Does anybody know the head chamber volume of the TU5J2 head? Trying to work out the compression ratios using the various pistons available and how much of a skim I would need etc

 

Would like to stay N/A yes, turbocharging adds another layer of complexity, and a lot of expense and thats before I start breaking chocolate MA gearboxes!

Edited October 18, 2006 by RossD

[Sandy 191]

I don't see any dimensions there

"something silly like a 2+mm skim"

 

No more scientific than my post!