Xu7j4 Engine

[phil05 0]

I can have one of these engines out of a mates car for nothing if i want it and i was just wondering if it is worth getting one for a 205 conversion. Can anyone answer a couple of questions for me please :-

 

What is it like to fit one of these to a 205?

What do you need to replace? (manifolds etc)

Is the wiring like the Mi16?

What is the power of this engine?

and anything else i need to know about the engine conversion

Thanks for you help

[Sandy 191]

Someone's just done it, but forgive me, I can't remember who. I'm a big fan of the basic engine, it's got a must livelier nature than the 1.9 mi16, I ran one with GTi6 cams and bodies in my last 309; it was surprisningly strong low down too. But in standard form it's a big hamstrung by a terrible inlet manifold, with a tiny TB and choked inlet ports. Still, heaps of potential!

 

Largely irrelevant fact... it's the basis for the 206 WRC engine.

[Ahl 4]

Just curious, what makes this engine a better bet than the mi16, gti-6 etc?

[phil05 0]

cheers sandy309 what was it like to do the conversion do you have a tips or info on what they are like to fit also if anyone can remember who has just done the conversion then please reply on here cheers everyone

Anymore info you lot

[KRISKARRERA 2 1 Cars]

Isn't this the 1.8 16v engine found in various states of tune in the 306 and 406? At best it only had about 118 bhp so why is it so good? Though I'm guessing that if it's "only" 118bhp from a 1.8 it'll be so strangled that it'll make reasonable torque low down.

A friend had the 1.8 406 a few years back, I have to admit it went ok for a small engine in a big car.

[Sandy 191]

The standard engine has super mild cams (which can easily be swapped for GTi6 ones, much better) and is strangled by the small throttle body and inlet ports cast smaller to choke it. I simply put mine on TB's with the GTi6 cams and exhaust manifold, but a little bit of porting on the inlet side would make it even better.

This engine has a very different nature to the 1.9's due to shorter stroke, smaller pistons, less counterweighting and a lighter flywheel, meaning much lower rotational inertia, couple this with long rods and the piston speed and acceleration are completely different. The piston acceleration on this engine at 8000rpm is about the same as the 1.9 at 7250rpm; so it can and does rev more freely. The piston acceleration curve gives it a very cracking induction noise too.

 

There's a video of my old one here: http://noboost.com/temp/sandy/GoodyXU7J4.wmv

 

It weighs almost exactly the same as the 1.9 8v.

Edited January 16, 2007 by sandy309

[phil05 0]

What are they like to fit do you need to modify anything such as the manifolds or engine mounts etc. Any help would be great, cheers for the info sandy309 any more on fitting it. Phil

[Ahl 4]

How interesting. So would I be right to say that it won't have the ulitmate power potential of an S16, but is a 'sweeter' engine overall?

[pug_ham 244 3 Cars]

This engine has a very different nature to the 1.9's due to shorter stroke, smaller pistons

By smaller pistons I guess you mean the overall skirt lenght etc as they are the same bore as the 1.6 & 1.9 XU's at 83mm, only the stroke is different between the three engine cc's;

1.6 = 73mm.

1.8 = 81mm.

1.9 = 88mm.

 

I've seen a few of these engine's now in my local scrapyard with rods sticking out of the block, are they really prone to this happening?

 

Graham.

[Sandy 191]

I don't really have any other useful information to you Phil, I ran mine on a DTA so didn't get involved with the 306 electrics. The alternator and tensioner needs to be re-invented slightly to ditch the AC etc, but otherwise it's regular XU. Oh and trim the cam cover to clear the MC.

 

I knew that the early ones suffered premature ring and bore wear, but a full recall was done. I'm not aware of the rods being any less reliable than other XU's, indeed the geometry lends itself to better reliability. A friend of mine has built 8v and 16v competition versions of this engine, the 8v made 155bhp at the wheels and the 16v apparently nudged 240bhp at the flywheel, with 84mm bore and an 8.5k rev limit.

[TB_205GTI 1]

Sandy will the XU10J4RS be a good choice for the XU7? Or are the ports too large for it?

 

I'm thinking about putting it in a 205 GTI 1.6 (This is the only legal option here in Denmark). I agree with you that the carateristics would be a blast for the light 205. A few mates has ~ 140Bhp from 306 GTI manifold and inlet cam.

[Sandy 191]

I'd prefer them to be slightly smaller, but it's definitely going to be better than the standard head. I've just put a tidied up GTi6 head on a friend's XU7 bottom end, which will be running on TB's soon hopefully.

[TB_205GTI 1]

I'd prefer them to be slightly smaller, but it's definitely going to be better than the standard head. I've just put a tidied up GTi6 head on a friend's XU7 bottom end, which will be running on TB's soon hopefully.

 

I have the same thoughts, my conclusion is that the XU10J4R head will give a better torque curve when you don't fit TB's. Can you keep us updated on the XU7 TB project?

[Sandy 191]

Hopefully, the engine's ready, but I don't know how long it will be before they put it in the car.

[phil05 0]

cheers for the info you lot think im going to give it a go with a few upgrades will keep you updated

[phil05 0]

forgot to ask are the engine mounts the same or do i need some made

[Sandy 191]

You need the bit the bolts to the front of the block on the drivers side, but the gearbox and rear mounts are the same.

[phil05 0]

Cheers mate what do you mean i need an engine mount made for the drivers side or need to get one from a different vehicle. Thanks again for the info, i will properley asking for some more info down the line!!

[Sandy 191]

You need the drivers side engine mount that goes from the block to the inner wing, from the 306. That enables you to retain the normal 205 rubber mount and panel.

[phil05 0]

cheers for your help

[James_R 3]

sorry to dig up an old thread, can you bolt the Mi engine mount on the block instead of the cast iron 306 unit?

[Sandy 191]

No.

[welshpug 1,657]

edit; uses the same top arm as the 16v xu, but the part on the block is different.

Edited December 24, 2007 by welshpug

[James_R 3]

Ok thanks