306oc - Peugeot 306 Owners Club & Forum

Full Version: XU10J4RS head on XU7JP4 block
You're currently viewing a stripped down version of our content. View the full version with proper formatting.
Any ideas on performance gains? And would I need XU10J4RS cam belt etc?
You will need a XU10 cam belt, XU10 head gasket and i think XU7 head bolts.
I would imagine you would get a fair power increase if you also added the gti inlet and exhaust manifolds but this would all have to be on aftermarket management as neither the XU7 or 10 ecu will adapt for this.
Nice one, thanks.
So how much roughly for a decent aftermarket ecu?
Something like Omex, DTA, Emerald, you're looking at about £600 for the ECU plus £200 for a loom (can be cheaper if you're confident enough to build it your self) and then mapping on top which seems to change quite drastically depending on your location and mapper.
I think that in theory the XU7 has the potential to produce 160bhp from the use other XU parts, namely the XU10J4RS. Plus it's an alloy block.

Welshpug knows quite a bit about it.
(14-06-2015, 03:08 PM)Niall Wrote: [ -> ]You will need a XU10 cam belt, XU10 head gasket and i think XU7 hexu7 the manifolds and cams  bolts.
I would imagine you would get a fair power increase if you also added the gti inlet and exhaust manifolds but this would all have to be on aftermarket management as neither the XU7 or 10 ecu will adapt for this.


following this will give a big fat fail I'm afraid Niall!

cam belts are the same, you must use the xu5/7/9 hg, as the bore is 83mm not 86mm.

using the rs manifols is a no brainer,,apart from the tiny ports on the xu7 the manifolds hold it back, and the cams.

inlet valves are actually smaller on the rs head, but far larger port, xu7 valve springs wont really take the rs cam.

they can indeed make good power, seen results from one such engine on the 205 forum a few years back, one of sandy browns race engines made around 240 bhp, the only bit standard was the block liners and crank, head was a modified xu7, custom pistons rods and manifolds, cams to sandy spec.

the 206 wrc used this block as base for its 2.0 turbo engine with 85mm liners and 88mm stroke crank
Its lots of money to get there. Not sure I would bother!
Yes, you can get to 160 bhp in xu7 using exhaust manifold and xu10j4rs admission. Also useñ the command xu10j4rs valves. Fuel nozzles should also be the xu10j4rs ...

But you must use a programmable ECU. Here in Brazil has the possibility of using alcohol "pure" as fuel ... which increases the power.
Well I've already got the XU10 inlet and injectors, waiting to be put on and getting a XU10 exhaust mani is next on the list, then maybe the head and ecu depending on funds
(15-06-2015, 08:57 AM)connorp Wrote: [ -> ]Well I've already got the XU10 inlet and injectors, waiting to be put on and getting a XU10 exhaust mani is next on the list, then maybe the head and ecu depending on funds

Dont run the gti6 injectors. You want the 1.8 injectors for it to run properly with only the gti6 manifolds.
Ok then, whys that? I'm guessing the gti injectors will be trying to pump more fuel into the engine than it's being fed?
(15-06-2015, 09:58 AM)connorp Wrote: [ -> ]Ok then, whys that? I'm guessing the gti injectors will be trying to pump more fuel into the engine than it's being fed?

er... so the FPR will supply the gti6 injectors no problem. I believe you will experience overfueling issues. I used to run a gti6 inlet manifold and we definitely used the 1.8 injectors.
The engine won't know there's different njectors on and will just open them for the same amount of time as the 1.8 ones . Altough it will make some adjustment from the stft and ltft but there's a limit to how far it can go
if you're going to RS cams then you'll be sucking in a lot more air which in turn needs more fuel, I doubt the4 XU7 injectors will be large enough however the XU7 mapping will not be anywhere near what the RS needs.

a mappable ecu is a must.
even if you put RS cams in the rev limit is lower on the 1.8 so itll cut out before you see the benefits.
So is the verdict not to run the injectors?
(15-06-2015, 02:46 PM)Eeyore Wrote: [ -> ]even if you put RS cams in the rev limit is lower on the 1.8 so itll cut out before you see the benefits.

In fact you can do the framework of cams RS following the pattern of XU7, ie at a lower rotation.
If you're doing anything like changing cams, manifolds, heads etc - there is basically NO point in doing it unless you're adjusting the maps afterwards, it'll change it so much you're not going to see the benefits.

The only way to do it is to put the J4RS head complete with cams and manifolds, injectors, fuel rail and original FPR on the XU7 bottom end and plasticine it to make sure you've got enough clearance for valves. As said by Welshpug, you must use the gasket from the 83mm bore engines i.e. XU5/7/9.

Then it must be mapped accordingly - doing anything else is just pissing in the wind.
If changes are only exhaust manifold and the cams XU10J4RS.

I see no immediate need for adjustment in the ECU map.

The change in the ECU map is mandatory when we installed the XU10J4RS intake manifold.

For full installation of XU10J4RS head at the bottom of XU7, would have to see fits the pipelines of water.

Does anyone here use XU10J4RS head on the block XU7 ???
it will fit fine, the casting is identical, just differences like valve diameter port shape and spring seats.

you should change the mapping when you install different camshafts, you should also change the valve springs.

same applies to inlet manifold and injectors.
I use to have the overfueling with RS injectors in XU10J4R in my 406 without ECU remapping ( My 406 have Inlet Manifold, A pair of GTI6 camshaft & Custom made 2.2" Exhaust system)

At the idle, Sometimes self-reving , Black Smoke and rough idle.

During Accel, Poor initial accel. the RPM will quick kick after 4K rpm (But I think std. XU10J4R was better)


So, I decided to take off the Green Injectors from RS and back to the stock XU10J4R instead, Until now they can run well without the problems not sure bout the HP and torque gain but I think it's a lot better than standard.

[attachment=24006]
Exactly, I use the XU7 only the cams and exhaust manifold RS + K & N Inbox is the result was very good.

Around 140hp.

No quanlquer change in the ECU map.

It was made the framework of the cams in order to work in XU7 swivel range.

Even 4.000RPM operation is almost the same, but after the 4000RPM it comes pretty strong
(24-06-2015, 06:54 PM)Dollores Wrote: [ -> ]Exactly, I use the XU7 only the cams and exhaust manifold RS + K & N Inbox is the result was very good.

Around 140hp.

No quanlquer change in the ECU map.

It was made the framework of the cams in order to work in XU7 swivel range.

Even 4.000RPM operation is almost the same, but after the 4000RPM it comes pretty strong

Do you have an XU10J4R engine?
Not

Xu7 1.8 16V + camshaft XU10J4RS + exhaust manifold XU10J4RS + k&n inbox.
You managed 140 with that setup? Thats impressive... means the cams alone on the stock map are adding about 13hp.
13? you mean 25
Surely though with bigger camshafts you're allowing more air into the cylinder resulting in a leaner operation due to the lack of additional fuel. Not to mention the messing around with the end of injection and proper fuel atomisation if the valves are opening sooner

It's said by the guy who does alot of the k series mapping that just dropping 135 cams into a 120 engine without the map to correct for the changes results in the engine running dangerously lean top end.
you are correct.
(25-06-2015, 11:24 AM)welshpug Wrote: [ -> ]13? you mean 25

Sorry im basing this on that I have XU7 with gti6 exhuast mani, bodies and ecu and its only putting out 129.  Minus like 2 hp for the bodies or something pathetic like that it looks like the cams without any custom mapping add 13 just on their own!
Is using the exhaust pipe how many inches?