XUD7 strength ?

[nominous]

OK. This is a 306 forum and it's all about the XUD9, but this is the XUD section...
That said, I aint found too much about XUD7TE modding reading around here.
Only that they are more susceptible to heat and head lifting than the XUD9.

Is there a limit to these with a reasonable sized VNT (haven't got that far) without having to trade up to a XUD9 ?

Reason being that for doing my swap, the Rover sourced XUD7TE lump makes more sense. More so because of the gearbox it comes with which will make my swapping easier, but to get one I'll likely need to buy the whole damn car anyway...

[bashbarnard]

You want to wait a few weeks as pugmanxud is building a high powerd one atm vnt an all. He will soon find the weak spots

[welshpug]

as far as I know they are nigh on identical but a smaller bore, so possibly more meat in the block.

[Ruan]

Very much similar to XUD9.

The crank is technically weaker, though I've NEVER seen or heard of a smashed up XUD7 or XUD9 crank, the XUD9 one is burnished steel, the XUD7 one is simply a plain steel crank.

Theoretically yes, more meat between the bores, but I've never heard of anyone cracking between the bores before... Conrods should be the same item essentially.

[pugmanxud]

Eve' all. Yes. going big power on an xud seven soon. HDI rods are going in and mls head gasket too. keep an eye out on my project thread and you'll see!

[nominous]

I am watching it
Hurry up

Similar arguements made on the Isuzu 1.5 and 1.7 lumps. More power made with the 1.5 lumps due to metal between cylinders.

Is the rod/stroke ratio listed any where for the XUD7 and XUD9 and XUD11 out of interest ?

Is it possible to bore the XUD7 out to XUD9 size or are teh sleeves not thick and strong enough to accomodate that ?
I did read that the heads are different and a XUD9 head wont go on a XUD7 head - dunno, not convinced yet.


I'm figuing to grab the box, shafts, starter and mounts from teh Rover and chuck them on the XUD9 engine instead. Then I don't need to source a whole car to make a box fit as the Rover box is a mirror image of what I'm used to. Plus it can take a Torsen LSD and selectable ratios

If the XUD9 and XUD7 have the same footprint, this is becoming easy

---

The XUD7 has a displacement of 1.8 L (1,769 cc), with a bore of 80 mm (3.1 in) and a stroke of 88 mm (3.5 in).
The XUD9 has a displacement of 1.9 L (1,905 cc), with a bore of 83 mm (3.3 in) and a stroke of 88 mm (3.5 in).
The XUD11 has a displacement of 2.1 L (2,088 cc, with a bore of 85 mm (3.3 in) and a stroke of 92 mm (3.6 in). ATE/BTE

[pugmanxud]

Its pointless boring out an xud7 to an xud9 capacity. The crank will be out of balance to the mass of the bigger pistons anyway you can pick up a running good xud for less than £100 if you look hard enough

[Uberderv]

http://www.christiantena.pwp.blueyonder....gines.html

Some engine info^^^^^

[andyyy]

Mine for apparently no reason and without any warning overheated (literally in a split second looked down at temp gauge sitting at 90 looked down again well over 120) going down the motor way and seized solid only experience with them

Not saying there all bad just my 2 cent

Left me 80 miles away from home down the M40

[welshpug]

Its pointless boring out an xud7 to an xud9 capacity. The crank will be out of balance to the mass of the bigger pistons

what utter bollocks

[Ruan]

Its pointless boring out an xud7 to an xud9 capacity. The crank will be out of balance to the mass of the bigger pistons

what utter bollocks

Was kinda thinking that, the crank isn't balanced to the piston/conrod assembly...

[pugmanxud]

When I enquired about it at the engine builders place doing my head skim thats what I was told! but then he also said I would never get any more than about 130bhp on the standard c/r and rods etc.

[Ruan]

When I enquired about it at the engine builders place doing my head skim thats what I was told! but then he also said I would never get any more than about 130bhp on the standard c/r and rods etc.

Hahaha, outstanding...

Amount of "Engine Builders" and other engineering places I've been to who give you the old "I've been doing this for 40 years" bullshit yet have't a f*cking clue, had one company who I'll quite happily name as Richard Bros. in Redruth, Cornwall who decided to give me abuse because I had fitted an 11mm pump element to a VE and couldn't possibly believe how out of calibration it was and how close to destroying my engine I was - Forty Thousand miles later, still operating quite nicely thanks

[pugmanxud]

Haha! the place is ELB engineering in sudbury. Meant to be quite reputable amongst the local tuning scene. says it all really though. The local tuning scene is redtop corsa a's on standard brakes and shocks with chopped springs...

[bashbarnard]

I use a place called randels. Really smalk company that operate out of what can only be descirbed as a shed. But they are far better than any others. Let me watch stuff while they do it and between the family have loads of experience in race industry with lightning rods stock cars drag cars etc. Highly recommended

[pugmanxud]

Sounds just the place tom. Sounds like my work!

[strictly_perv]

I stripped down my old XUD 7 a few years back and compared the internals and they looked identical except the pistons. I may still have a rod and piston lying around if you wanted a picture?
I know the head bolts were quick a lot shorter, without a spacer and silver in colour.

[nominous]

More info would be happily received, so a picture would be great

I found a Rover 418SD in the scrapper and it's quite differently mounted.
In a 306 the engine is cantered over say 70 degs from vertical ? In the Rover, it's 80 deg. ie: it sits more straight up.
This seems to be in order to clear the firewall as in the pug that's further back and the Rover has the master cylinder in the way potentially.

Holy hell, there are a lot of pipes behind that engine.
The pipe routing to the rad seems to be made worse as they picked a rad with hoses on the wrong side. Almost like they went to the parts bin than finding a new one.
PAS and vac take offs are on the cam ?!? The PSA pump sits at the back of the engine bay. Very odd.

Reasons to use the Rover box are that it's a PG1 so LSD's are piss easy to source. it uses standard Honda/Rover drive shafts so they would fit my axles without having custom shafts made up.
Only remaining issue is finding a donor for reasonable money. I could likely grab the contents of this Rover's engine bay but I've no faith the XUD7 in there is going to run.
Tho it looks complete, it's been there for a few years...
But the best way to get the parts then potentially bolt them to a XUD9.
Still quite a few differences between the engines, dipstick area, water housings (all metal!!)

Of course, it was a Lucas