4 Questions

[HERMAN 33]

1. I am slowly rebuilding a 1.9 gti and the engine is fully stripped. Is it worth getting a XU10 head for it or getting my XU9 head rebuilt. It needs new guides. What sort of price can I expect to pay for getting my XU9 head ported, gas flowed and new guides? Does any body have any figures for the XU10 head is better than a well sorted standard head or are there reliability issues?

 

2. I will also be doing some trackdays and I am wondering if it is worth bafling my sump. As any body got any pics or is it not needed on the XU9??

 

 

3. I am assuming that the higher oil pressure spring gives you higher oil pressure. Does this have much advantage or does it just make the pump work harder?

 

4. What sort of price can I expect to pay for getting the bottom end balanced?

 

I have done several searches but I am getting confused now

 

Thanks

Neil

[Baz 421]

Baffled sump is always a good idea, and there's some good info on Xu10 heads etc as you've probably found, really up to you and budget which way you want to go, & whether it's worth it.

[Saveit 0]

Hi Niel,

 

XU10 is definitly worth it - IF you also have a racing cam of some kind for it. You will need a cam with good lift to get the full advantage over the XU9 head. Specs is pretty simple: The XU10 head has bigger valves (cant remember precisely but i believe it is around 1mm bigger), the chamber design is better, the general flow is around as good as a ported XU9 head, and the sparkplugs sits vertical instead of diagonally which should improve ignition. Especially the chamber design and the bigger valves is the main reason for it being better than the XU9 head. And there is no reliability issues with the XU10 as apposed to the XU9. Baffeling the sump is not needed on an XU9 engine, but its always good to do.

[Miles 331 1 Cars]

I'd get the 1.9 head rebuilt with slighter larger inlet's, The ports on these are better and the combustion chamber's are the right size too

 

Balancing, Depends on where you go and the quality of it, so anything from £50.00 upwards

[Saveit 0]

WHy get the head rebuild with slightly larger inlets :S ? Why not use an XU10 head instead. With an XU10 head you will not only get larger inlets, but also a better designed chamber, vertical sparkplugs and a better flow. The XU9 and the XU10 head are so similar, that it would be stupid spending money on getting larger valves and what so in an XU9 head, when you can pick up an XU10 head for a candy.

[Miles 331 1 Cars]

Maybe, But the inlet ports are wrong, Exhaust port's restrictive etc etc, It's a personal thing but having driven a 205 with a XU10 head on I don;t know what all the fuss is about

 

Baffling is a must as even 8v get's surge on track without too many problems as do the XU10's.

[Saveit 0]

Now, i dont know which XU10 you have driven, but clearly something has not been done correctly. The two most important things when doing the XU10 conversion, is to get a real racing cam with a high lift, and to get the head skimmed enough to raise the compression. Several XU10 conversions has been done without changing the cam to a cam that is agressive enough. Then you will feel a lack of power yes.

[Miles 331 1 Cars]

It did have a cam and the compression done, All set up correctly by a nameless firm which has got a very good rep, Compared to my std 1.9 it went around the same, But as said it's one of those mods you love or hate, If I was going to use another head it would be off the 405 SRi with the downdraft type of port.

 

Oil pump spring, just buy the XU10 6bar one from Pug, Only around £4.00 from memory, no need for any more

[Guest turbo_jay]

hi there am i right in saying that the xu10 head is off the 406 turbo engian??

if i am right in saying this ,i have one up for grabs as i have a spear xu10 engian with

the crank gone and i wunt mind parting with the head .

kind regards jay

[Saveit 0]

I cant say if the head on an 406 turbo engine is an XU10. The head normally used in this conversion is the head from fx. a 306 2.0 XSI 8v. This is an XU10 head.

[omega 82]

this is getting intresting

[Miles 331 1 Cars]

It's the same design, Not sure on CC of the chambers or valve sizes thou,

 

The engine was found in any 8v 2L Pug/Citroen so loads, Pay much more than £20,00 for one and it's too much.

[HERMAN 33]

Thanks for your imput guys. Does anybody have any pics of a baffled sump to give me an idea of how it is done?

Going back to the stronger oil pressure spring I understand that you use the one from the XU10 but I am still not sure what the advantage of this is??

As for which head to use I am going to get a price on geting my head reworked but I will also start looking aroung my local scrap yard for an XU10 or 405 sri head and I will weigh up the pros and cons then.

Thanks again

Neil

Edited January 3, 2009 by HERMAN

[jplautomotive 0]

hi

 

yeah i baffeld the sump on my xu9 mi16 and did a windage tray bigger oil pump drive gear and longer chain

and also 6 bar spring instead of the 5 bar one

 

Edited January 3, 2009 by jplautomotive

[Miles 331 1 Cars]

You still get surge with the Trap door sump thou most don;t, I have used a Multi tap door baffle from France, Mush like the BTCC car's used

[Anthony 1,000]

I've run an lightly fettled XU10 head on an XU9 bottom end for a while now and it seems to work well. I've not rolling roaded the car at all so I don't have a power/torque figure for it, but it's quicker than other XU9 engines that I've owned/driven and works superbly - tractable from pretty much idle, pulls well all the way around to the limiter, and returns excellent mpg.

 

Whether a flowed XU9 head with bigger valves would have been better I don't know, but for the price this engine cost me to put together I really can't fault it. A few people on this forum have driven or passengered in the car, and have generally commented that it feels quicker than a humble 8v has any right to.

 

I also run an XU10 baffled alloy sump off an S16, and it's good enough for track use even on semi-slicks like R888's and ACB10's - good enough that there's no movement of the standard oil pressure gauge anyway. I run the sump as it would be on an XU10 (ie without the spacer/stiffening plate for the XU9) using the XU10 bolts, and that's been fine.

[HERMAN 33]

Great pics JPL the sump that you have used is that an MI16 sump or an XU10 sump because it looks deeper then the one off my XU9? Also the windage tray that you fitted is this a pug part that you have modded to fit? Also what is the advantage of the larger oil pump gear and are the gear and chain pug items?

Miles do you have any phots of the sump that you used or any more information on it thanks?

Thanks for the reply Anthony do you use a high lift cam?

Neil

[jplautomotive 0]

hi

 

it is xu9 mi16 sump , windage tray is xu10 and (moded to fit xu9 sump spacer) so is pump drive spring and chain , bigger drive sprocket means pump driven faster

[HERMAN 33]

Thanks JPL I will get to the scrapers and start searching.

[Anthony 1,000]

Thanks for the reply Anthony do you use a high lift cam?

Only a mild Kent PT36 which isn't drastically different to the standard GTi cam