The V8 Owners Forum -

Hmmmm....

I've got a rover v8 that came already dismantled. However, I can't see any markings on the crank caps to determine which order they came out.

How critical is refitting them in their original order?

Also, this block has the lugs for the cross bolting (but "normal" end caps). Is it possible to get new "later style" end caps fitted and have the whole lot cross bolted?

They have to be matched, mismatch and you will kill the engine.sgould be marked F F2 R2 etc with an arrow pointing towards the front of the engine

volospian wrote:
Also, this block has the lugs for the cross bolting (but "normal" end caps). Is it possible to get new "later style" end caps fitted and have the whole lot cross bolted?

Yes you can do that. And part of that process would be line-boring, so you'd sort out the main-bearing-cap issue you have (well, you'd ditch the existing caps!)

Chris.

Any suggestions on who could do that? I'm in the midlands area.

ian.stewart wrote:They have to be matched, mismatch and you will kill the engine.sgould be marked F F2 R2 etc with an arrow pointing towards the front of the engine

Ah, I just cleaned a few up a bit and the first one I looked at had what appeared to be 2 cast lines, but after a clean they look like a 1 and an arrow. The rest have other marks, including what look like numbers and one with an F on it, I think. There's what looks like a 3 on one and a 4 on another...?

Does that sound right?

I'll give them a proper clean tomorrow and see if I can get a better idea.

They will be numbered 1-4 with a arrow.
No 5 (the big end one) may nto have a number

OK. The block itself looks nice. The bores look clean enough and undamaged. Everything, at first glance, appears to be fine, and there doesn't appear to be any cracking around the threads for the caps. I haven't checked for signs of fretting yet, but I imagine there could well be some anyway.

The old bearings are worn right down to the copper so I think the cank will need a regrind, so...

Is it worth getting new x-bolt style end caps fitted and the whole lot cross bolted and the crank bore line honed? The engine is staying at 3.5 as the bores are OK and I'm not after huge power to start with, I'd be happy with around 200.... but I am thinking of potentially a twin turbo set up at a later date.

I just wonder if it's worth x-bolting it while it's all stripped anyway, just to eliminate any possibility of fretting and/or cracking later. Any ideas on a price for this or is it just cheaper and easier to stick with studs/nuts and to buy a proper x-bolted block if I want to go that way later?

How much would a crank regrind cost, roughly? I see RPi are doing reground cranks for £128. For that price is it worth just buying one of those and chucking the old crank?

Also, with that in mind I'm assuming I could use a later 4.2/4.6 or something crank with new rods and 3.5 pistons, to provide a stroked 89.9mm engine? If so, what is the best set up, or is it just worth sticking with the shorter throw of the standard 3.5 crank?

Are you saying you have a 3.5 block, not a 3.9 block, with the undrilled lugs for x-bolts?? If so, wanna sell it?!

completely confused here, a 3.5 block that just has the bosses for cross bolting? Yes there are cross bolt 3.5 blocks but they aren't the same as the 4.0/4.6 blocks. To answer your other queries we need to know exactly what this block is.

If you have a 3.5 with the facility to x-bolt, it would be a good base for a turbo motor as the space between the bores is thickest (i.e. strongest) in a 3.5.

You could fit a later type crank by having the mains turned, or even the block, but it would require new liners and be a complete waste of time & money if you plan to stick with the 3.5. Usually the later type cranks are fitted to increase capacity.

And besides, if it is a 3.5 with xbolt facility, its a rare block and one that shouldn't be messed with apart from machining in the xbolts IMO!!!!

chodjinn i've got one of those 3.5 x-bolt blocks. The cross bolt work is already done and has the small main journals. I was selling it last year but ended up keeping it. I was keeping it with thoughts of a hi-po future turbo engine but since I haven't even finished building my n/a motor then I think I should probably sell it. PM me if you're interested.

That's what I'm thinking, but there are what looks, in all the pics I've seen, to be the lugs ready for cross bolting.

Or am I getting it all wrong? Here's a pic of the "lugs"


and another from a different angle...


The Cam is not drilled for a thrust plate...


It's a stiff block...


You can see it's a bit shiney, this is, I assume, from fretting, but there doesn't seem to be any actual cracking around the bolt holes


It has the "standard" type caps, not those designed for cross drilling though


It's definately 3.5, so am I getting it wrong? Can it be cross bolted, or not?

lol, can you tell I'm a newb

chodjinn wrote:If you have a 3.5 with the facility to x-bolt, it would be a good base for a turbo motor as the space between the bores is thickest (i.e. strongest) in a 3.5.

You could fit a later type crank by having the mains turned, or even the block, but it would require new liners and be a complete waste of time & money if you plan to stick with the 3.5. Usually the later type cranks are fitted to increase capacity.

And besides, if it is a 3.5 with xbolt facility, its a rare block and one that shouldn't be messed with apart from machining in the xbolts IMO!!!!

Yeah, I meant to just increase capacity by stroking, but if it needs relining anyway, it is, as you say, pointless to stick with the 89.9mm bores.

I'd rather keep it 89.9 bore, so it looks like that idea is out the window

That block has the bosses for the x-bolt but you will need different caps, i'll try to get out and take some pics of mine. I don't know how much it will cost to have the work done.

That's what I was thinking. If I have it done, is there anything else worth doing at the same time?