Which 16v Head

[wardy18 33 1 Cars]

Following on from the other thread

 

Which head is the better option to fit on a 1800 race XU9 bottom end with 45 Webers and intruder Mi16 Pistons:

 

S16

Mi16

GTi-6

 

Thanx

 

Simon

[welshpug 1,661]

will the head get a reworking or just bolted on?

 

S16 and Mi16 are the same (effectively, minor details differ but nothing that'll affect this decision)

 

GTi6, massive ports, may be too big??

 

XU7J4, smaller ports than GTi6, more favourable to rework.

 

XU10J4R (135bhp late 2.0) not as restricted as the XU7, but not as balls out as the GTi6.

[James_R 3]

Also depends if you're going to replace the valve train aswell, GTi-6 has th ebetter valve train std, but if you're putting big cams etc.. in then it's either XU10R or XU7 depending if you're porting it at all before use.

 

Also 6 heads go for silly money £200+ where as a bogo R head is worth £20-50

[wardy18 33 1 Cars]

would probably be ported and polised before i got it sent over to me

 

arnt the XU10J4R quite hard to get hold off?! sounds like the ideal head but GTi-6 sounds like it'll save porting work

 

like Sandy said to me the XU7 is like a blank canvas so the ports can be shaped to whatever u want whereas there's not much scope with the GTi-6

 

then again i am on a tight budget and so dont wanna spend silly amounts so with a budget in mind whats the best option?!

[wardy18 33 1 Cars]

OR i could just go with Hi Flow Heads new Stage 6 8v head, using a XU10 head and increasing the valve size yet again, so if you like a Ultra Big Valve Head

[Batfink 201]

big valves will kill all low down torque most likely.

The head should be matched to the cam and bottom end, it should not be bought as an 'off-the-shelf' item.

 

This is where you need to speak to your enginebuilder, work out a build/budget and let them get on with it. Rarely do you get good gains by looking at individual parts. Once you have a spec mapped our you can go on the hunt for parts

[wardy18 33 1 Cars]

my olny problem is my budget, ive got to remember that my racing is only a championship on this one island and i also really dont have the money to spend so trying to get the best from what i have

 

my main concerns with converting to 16v is:

 

purchasing the head itself and getting shipped over to me

having to buy a new exhaust mani and fitting it to my system

buying a new inlet mani for my carbs

and worst of all a set of rally cams AGAIN as my 8v will be no use

 

I know 16v is definitely the way to go from what everyone has said but for me at the end of the day its teh wallet that rules and being on an island with no tuners at all makes it twice as expensive

 

i think the plans for next year will be to ask Sandy to supply and do his work to the crank/pistons/rods to get me to 1800 (i already have an XU9 block spare i can use for these parts) then if funds allow. source a XU10 head and see if i have enough for some slight work to it before i get it shipped over to match the 1800 bottom end (maybe speak to Sandy again). this way i can retain all my current mani and expecialy the cam

 

whats the thoughts on that plan?!

[Sandy 191]

The XU10J4R head from the 306/406 would be my choice. I really don't think there's much to choose between it and the GTi6 head; plus it has a wasted spark coil pack, no servo pump, no spray rails and the easily re-fitted black plastic cam covers (from '98); all of which I see as advantages. A set of Catcam single springs gives you a sufficiently wide cam choice too.

[wardy18 33 1 Cars]

The XU10J4R head from the 306/406 would be my choice. I really don't think there's much to choose between it and the GTi6 head; plus it has a wasted spark coil pack, no servo pump, no spray rails and the easily re-fitted black plastic cam covers (from '98); all of which I see as advantages. A set of Catcam single springs gives you a sufficiently wide cam choice too.

 

I did mean the XU10 8v head from the 206 2.0ltr, the cheaper way to a big valve head

 

The XU10J4R would be my prefered choice but i really cant afford a set of new cams plus valve springs, inlet and exhaust mani and actually sourcing this head itself!!

 

With the XU10 i can see what funds i have to source the head then maybe see whats funds are left for a slight port and polish to 1800 bottom end spec then i can get it over here and put my catcam and double valve springs in, is going to be the cheapest and most effective way for me at the moment, do you know of any XU10 8v heads kickin around at the moment Sandy?!

[Sandy 191]

No.

 

Even a basic 16v head with mild cams/GTI6 exhaust will take you clear of a well matched 8v head/cam/manifold I would think.

[wardy18 33 1 Cars]

i suppose i can always sell my 8v for a fair amount with the cam to fund the new head

 

i think i just scared of the conversion lol

 

Sandy - could you give me a quick list of parts i would need for the conversion to the XU10J4R head on the XU9 1800 block and where i can get these from for the off the shelf bits and ill try and source the parts and see what the cost will be, ill be running 45 webers until i can afford bodies so no loom to worry about

 

Thanx for your help and convincing mate

[SPGTi 2]

There is a long thread on here where Puma racing discusses the XU10 8v head. The consensus being :

XU10 8v head a decent mod when heavily skimmed (to get a sensible CR) and bolted straight on in the place of a bog std XU9 8v.

As soon as you start to look at porting / polishing / modifying the heads the XU9 8v is the better one to use compared to the XU10 8v.

From reading the thread, looking at what you want to do, if I was in your position I would spend the money on a 16v of some sort. I think staying with 8v you will be spending hundreds for a couple of BHP, whereas with the 16v options you will get a big bhp increase for the the same money and not have a peaky, "highly strung" engine that would probably require more frequent rebuilds.

 

Steve

[wardy18 33 1 Cars]

There is a long thread on here where Puma racing discusses the XU10 8v head. The consensus being :

XU10 8v head a decent mod when heavily skimmed (to get a sensible CR) and bolted straight on in the place of a bog std XU9 8v.

As soon as you start to look at porting / polishing / modifying the heads the XU9 8v is the better one to use compared to the XU10 8v.

From reading the thread, looking at what you want to do, if I was in your position I would spend the money on a 16v of some sort. I think staying with 8v you will be spending hundreds for a couple of BHP, whereas with the 16v options you will get a big bhp increase for the the same money and not have a peaky, "highly strung" engine that would probably require more frequent rebuilds.

 

Steve

 

Thanx for the info mate, im pretty convinced im gonna convert to 16v (need make sure regulations allow for hillclimbs first lol)

 

As im already dropping the cc to 1800 of the XU9 block im gonna need everythin i can to make the short fall in power and plus i can sell my 8v head which is a well sorted head with a heavy skim and a very good cam to fund the 16v

 

i must say that big grin comes everytime i stand behind the exhaust and feel the compression out the exhaust from a heavy head skim giving 10.8 CR on the XU9 8v head im running, i can stand a metre back from it and still feel the pressure as if i was right up close

[petert 588]

I agree with Sandy. The XU10J4R head is very underrated and would be my preferred choice, even with the standard valve train. You can always upgrade cams later.

[guffe 2]

Sorry about draging this up, but it was closest that I could find...

 

Is there a hole for the cam sensor on XU10J4R head like the RS has? Or is the XU7JP4 only one without the sensor?

 

I have freshly worked XU7 head for my project and just wondering where I could stick a cam sensor

[Richie-Van-GTi 72 2 Cars]

no hole in the xu10j4r head no.

[guffe 2]

Ok, so it's drilling time... Anyone have a pic of the original hole and sensor at RS engine? I haven't got the sensor yet, just wondering about the installation. I've seen the sensor at servicebox pic, but I would like to know if it really looks like it.

Edited August 28, 2008 by guffe

[BackStreetRacecars 3]

Esp compared to the cost of a stage 8million Super mega massive 5 thousand angle valves Hi-flow head.

 

 

absolutely hilarious.....