Xu10j2 Head

[Saveit 0]

Smooth the sides off. Otherwise you will have edges interfering with the flow. You "eye browe" it to make more room for the air to flow around the valve and therefore you would also smooth any edges out.

[BackStreetRacecars 3]

quick question..... is this using mi16 liners or 8v ones?

 

just before I make a comment and make a tit of myself!!

[wardy18 33 1 Cars]

8v mate

[wardy18 33 1 Cars]

Please see a little more detailed pic on this whole idea then......

 

One concern, where the copper gasket has also been relieved would the areas CIRCLED IN BLUE not become quite weak due to not having the strength of the full inner circle circumference of the gasket?!

Edited July 29, 2009 by wardy18

[welshpug 1,661]

all this faffing worth it when you can bolt an XU9 head straight on??

[DrSarty 90 1 Cars]

all this faffing worth it when you can bolt an XU9 head straight on??

 

That was kind of my point earlier.

 

Sorry the below doesn't answer your question, but it is relevant.

 

I certainly admire the effort and encourage you to experiment. I would advise though to be careful with copper (Cu) head gaskets. I had one - and yes I got advice before I fitted it about the risks - which failed quite quickly, and it was down to not having sufficient liner clearance/protrusion from the block.

 

They should also be fitted with a type of Cu adhesive gasket spray which was quite tough to get hold of. I got it from a US engine part supplier in Bedford although it's probably available elsewhere.

[wardy18 33 1 Cars]

the point is that i can spend 250 - 300 for an XU10 head and get say 60% of the power increase that spending 900 for a BV XU9 head could get me!! I like that ratio alot better with my budget in mind

 

Matt from QEP has flatly stated that valve shrouding isnt a major issue as he has done alot of flow bench work with this head on a 83mm bore, im just intrigued at the whole idea of it!!

 

to be honest messing around with relieving gaskets sounds like its a recipe for disaster so i think ill smooth the edge of the liner slightly to remove the sharp edge just on that section and see how it goes, i will be running a 83.5mm gasket so have a little room for eye browing the bore before coming to the gasket edge

[welshpug 1,661]

but has anyone actually PROVED that an XU10 head on an XU9 block works better than a lightly worked over XU9 head?

 

Do you really need to spend £900 on an XU9 head to improve on an XU10 one?

 

you have to balance out the faffing you'd need to do to change your current setup to make it work on XU10 stuff, whereas you may have a slightly higher outlay on the head, but no faffing at all with your current ancillaries bar the tuning of them to suit the higher specification.

[wardy18 33 1 Cars]

not sure what other ancillaries your referring too, water/dizzy housing bolt straight on from XU9 to XU10, Catcam and Double Valve Springs swap straight over, Xu10 head will be port matched to my carb inlet mani, 4 branch mani will fit straight on

 

please advise what i have missed

 

i understand what u mean thou, can i spend £300 on an XU9 head and get similar or better results than spending £300 on an XU10 head....ANYONE?!

[mfield 20]

http://www.autosprint.co.uk/?p=p_12

 

just an idea on costs

[wardy18 33 1 Cars]

any ideas on the credibility of their work?!

 

how would i ever know if spending £395 average with them would get me better reults than a XU10?

 

anyone know there work?

[wardy18 33 1 Cars]

XU10 head now on its way to QEP for some quality workmanship by Matt

 

Cant wait to get it back and get it fitted to feel the results

 

No idea what BHP to expect, i would like 180bhp but am really unsure especially when running self set up carbs

[taffycrook 2]

I had a XU10 head done by Matt a few years back for a 1600 rally car. The brief was make it more powerful, with a budget of £1000.

There are a few options with that sort of budget, but I wanted a progressive build. One that taken a stage at a time would give the car more power, without upsetting its balance. The car was doing well, but lacked outright speed and torque out of slower corners.

Starting from a std base 1600.

Higher CR is a must, for the first thing to consider is the cam. We used a cat cam rally profile and vernier.

The vernier is due to the amount of skimming to achieve the desired CR.

That was put together and using the std ecu with the rev limiter removed tested.

Proof of the extra flow capacity of this set up was the need for more fuel, it was running lean!

An adjustable fuel pressure reg was fitted and it won its next two events (in class).

Within budget and very effective.

 

But enough is never enough, and next we fitted eletric power stg, and twin 40's along with mapped ign.

This was all set up on a dyno and yielded not specatular results but a solid 144 bhp.

It won the chapionship for its class.

 

1.9 engines are 1.19 times bigger so a rough rule of thumb would give 172 bhp.

The missing 8 horses are in there but with bigger cams, more CR and funny fuel.

[wardy18 33 1 Cars]

Nice, thanx for the info, is great to read others experiences with this set up!!

 

I had forgotten about mapable ignition, without a Rolling Road on the island i really struggle to set the Ignition timing perfectly and just placed where i think at the moment

 

What system do you run!?

 

Note........ Also just to add for those 8horses extra, im runnings Twin 45's

[DrSarty 90 1 Cars]

Note........ Also just to add for those 8horses extra, im runnings Twin 45's

 

I think one of the points made here a few times is that everything's connected. If you're making 172BHP, then an extra 8BHP is another 5% gain which is quite difficult to get, and just throwing bigger ITBs or carbs on means other things are effected too, and you will need to get more air in (and exhaust out) to go with the extra fuel, which in turn perhaps needs different cam profiles, timing and CR.

 

All of this is going to need very careful setting up or mapping, which along with component selection and installation quality is where the real skill lies.

 

But even that is a compromise once it's running OK. You can probably get your extra 8BHP, but at what cost? Not financially (although that eventually comes into it), but I mean maybe you have to rev it harder, which may make the driving experience hardwork, shortens the life of the engine and at the same time giving you perhaps less down low to use.

 

I would not advise seeking high numbers. Do not feel disappointed getting even 169BHP IF the driveability and throttle response elsewhere in the rev range is fantastic. This is why Taffycrook said 'a solid 144BHP' IMO.

 

I would aim to get the best tractable power out of the bits you have, with the peak figure being just what it is. Someone with 5BHP more on the same set-up does not necessarily have a better car, as they may have made a sacrifice somewhere in terms of low end power, reliability or at horrendous cost.

 

Sandy said today 'my engine works' pretty much because of choice of moderate components, great build quality and an excellent set-up. Again this is very close to what TaffyC said, and I suspect a factor of his wins was finishing events/races due to reliability, whereas those always hankering higher figures may have just pushed a little too hard and then paid the price getting no cigar.

 

Matt/Nick+ at QEP will no doubt do an excellent job, and you will get excellent results. I'm just saying the excellence of those results is not always dictated by a single figure.

 

Keep it up though Wardy as it's very interesting. I like it when people challenge accepted norms.

Edited August 12, 2009 by DrSarty

[James_R 3]

I'll post up when I get mine on the RR, it's a XU7J4 bottom end (the 16v engine) with a std Gti head on a 282deg 12mm catcams and timing set slightly advanced on delimited 1900 management. be a good comparision.

 

Seems to go ok though

[taffycrook 2]

I had forgotten about mapable ignition, without a Rolling Road on the island i really struggle to set the Ignition timing perfectly and just placed where i think at the moment

What system do you run!?

Note........ Also just to add for those 8horses extra, im runnings Twin 45's

 

Mappable ignition is a must on this conversion, it brings everything together. It will be almost impossible to get the fuelling correct across the rev/load range(carb's) so where it is less than perfect you can compromise with the ign adv. We found a fair bit in high load lower speed area.

We used a KMS ign ecu it had a few teething problems, but it got there in the end.

If you could get to Jersey there are a few dyno's there, Highlands college has one, Harry the Jock has one in his garage to name but 2 off the top of my head.

But the only way to map the ign is on the rollers you can get close without them but not close enough.

I know you have 45's you wouldn't get 172 horses with 40's. I did some back to back tests on my track car and 40's held it back that was a xu9 8v. the 45's breathed much better at high rpm, with little or no loss of low speed tractibilty. Results were posted on here.

[wardy18 33 1 Cars]

so if I price up the kms system, is there any other makes that have been tried and tested with good results??

 

Gettin to jersey for a tune up isn't a problem as I can drive it there being road worthy, however their expertise in setting it up would be my only concern??

[DrSarty 90 1 Cars]

This is why you should get in touch (and build a relationship) with the mapper/rolling road owner first.

 

Find out what system they're comfortable with; then buy accordingly.

 

You'll get better results that way, because simply put, they'll know what they're doing. You may need to consider Emerald, Omex, KMS, DTA or perhaps something else, i.e. whatever they are familiar with. They all do the same thing anyway, however it's how easy it is for the mapper to understand the feedback and make assessments and adjustments that counts.

Edited August 12, 2009 by DrSarty

[James_R 3]

There's always megajolt for cheapy goodness or buying a full megasquirt and not running the injection on it

[wardy18 33 1 Cars]

to be honest guys i have not a scoody doo where to start with this mapable ignition, have jumped in on another thread regarding Megajolt but need some serious answers to understand even how the system works and how it fits in the engine department!!