V8: build from scratch or buy unknown secondhand?

[zoltan]

My 110 V8 has a rather tired 3.5 lump which is probably managing about 75 bhp at best. Compressions are good except cyl one which is not drastic but is about 25 psi down on the rest. Av is about 160psi throttle open. That cylinder also has a rusty plug so there is a water issue. In short it needs replacing. Its running mostly on LPG too.

Now the $64,000 question.

I have a 3.5 in bits which needs a crank grind, boring, certainly three or four guides are too sloppy, the rockers are shot etc etc. I will clean and polish the ports very lightly just to clean the casting marks.

Ive priced up the bits and in round terms to put the whole shooting match together properly with reasonable quality bits is looking about £1500 plus vat. That gives me 9.75:1 compression, up on my palty 8.13. Block bored and honed, crank ground and balanced with flywheel, valve guides bronze sleeved, exhaust valve seats fitted with LPG inserts. New cam, followers rockers, pushrods and timing chain/sprockets.

That is everything done. I've also splashed out on Megasquirt ECU and plenum so it will be pepped up from its current Strombergs.

I'll build the engine myself so no cost other than the bits. Do I spend this for a known engine or take a huge chance, albeit a cheap chance and put an unknown 3.5 EFi in at about £250?

I've considered upping the capacity and for whatever reason probably will stick at 3.5/3.9, I just plod about in it so I haven't got any great hankering for power over economy. The 110 is definitely a keeper.

Absolutely split on whether to chance the unknown or spend the dollar

??

[Retroanaconda]

Well I'm no expert on V8s, but for that sort of money you're straying towards a re-manufactured 'short' engine from Turner Engineering.

However, I would be inclined to try and find a good condition low-mileage EFI engine and MegaSquirt it.

Obviously the difficult bit is finding one

[mobyone]

at £1500 sheets, could you not get a 5.0 litre from the states? not too sure how much they go for, but they are just bigger versions of ours. the gm small blocks were in loads of old yank v8's. if you were to rebuild a v8, you may aswell get a better one first. hell, maybe the chevvy LS1 will fit. they are based loosely on the small blocks, but were ground up new designs too, so perhaps have different mounts/block dimensions.

just a thought though and i am not that familiar with them.

richard

[FridgeFreezer]

I'd say it's a better bet to find a good low-mileage 3.5, 3.9 or even 4.2, possibly still in a vehicle, and use that.

[zoltan]

I already have a nice 3.5 EFi which is reserved for my project. That was in a RR which I drove and it was quite a sweet engine. Since the project isn't going anywhere in a hurry I might as well rob that for the 110.

It is currently on an ZF autobox, I have just been out and taken off the torque converter, I assume other than needing a spigot bearing a manual flywheel will go on? Hopefully they didn't produce two different cranks?

I'd rather keep the manual box in the 110 and use the auto for the project

The more I think over it £1500 is a lot of cheap engines as much as I'd like the peace of mind of checking the internals over.

[Hybrid_From_Hell]

Flywheel is straihjt swap

As with the others go goof secondhand.

If poss listen and drive engine in LR pre buying, again if poss

and 9% certain to buy agree with seller to do a compression test, and

also lift driver side rocker and look at condition colour etc of inside

a real good guide.

Lastly check oil level You'd be amazed sometimes to what you'll see

mate once went to look at a L322 for sale, matey had spend serious money on a full valet

but engine oil was below minimum, showed that up till then he'd paid no attention

to looking after it, a full valet didn't cover up total lack of oil

A bnice 3.9 can be had for not a lot, and at least 1/4 of your rebuild budget, and if you do decide to

go the DIY Rebuild route don't do it to a 3.5, do it to a 3.9 at worst better a 4.6

Costs are pretty much the same irrespective of CC

Nige

Nige

[Quagmire]

HFH is right- I rebuilt a 3.5 for my 90 last year and even just rebuilding to standard spec soon added up.

Was great fun though and i would like to do it again, perhaps not to standard this time, and not with a 3.5 Just don't tell my girlfriend!

[nicks90]

i know someone that has a very well built 3.5 on carbs for sale - it was in his 110 challenge truck that he`s just dismantled (has gone to a 90 diesel).

He doesnt want much for it in the grand scheme of things, but it is extremely reliable and he knows his beans regarding engine building, It was bolted to an auto that was also fully rebuilt with uprated bits and bobs if you want to try for a deal on the whole package,

You can contact him via http://www.mksclassic.co.uk/ - Matthew Sykes

[Bull Bar Cowboy]

You would be surprised at how well a 3.5 can be made to go

However, in your position I would go for a secondhand engine of higher cubes, regardless of condition, an use that for the basis of a rebuild .......... in that way you end up with a more relaxed motor rather than a potential highly stressed 3.5.......balancing is not required unless you are using it for racing ..........most V8's balance out reasonably well from stock ...........just match lightest piston to heaviest conrod etc......

Its well easy to spend a load of cash in not achieving much gain for the average user ....... not like track engines where every single hp /ftlb counts big time.....

However,unless you are going for some serious performance parts then the pricing is a little adrift ………. to rebuild a 3.5 to OEM spec I would be looking at about £800 - £900 in parts & machining…………

Rebore + Crankgrind £300

Heads shaved 20 thou £ 30

Set of SD1 Pistons + Rings £170 (includes Machine shop pressing pins)

Cam + OEM followers £100

Big ends, Mains, Timing Gear, oil pump etc £100

Rockers + Shafts £120

Gaskets £50

If you then want to add in the goodies ………..add these in above OEM

Road Cam £ 75

Bleed down lifters £ 65

Cloyes Timing Gear £ 85

Head Machining £150 (valve guides lined ,shortened & seats cut)

ARP studs top + Bottom £200 (not needed unless you are going to 'use' the engine to its max ability

[Andrew Cleland]

Cam + OEM followers £100

ARP studs top + Bottom £200 (not needed unless you are going to 'use' the engine to its max ability

I'd love to know where you can get a cam and OEM followers for £100 - sh*tpart ones yes, but I put one of their cams in my 3.9 which I was rebuilding and wondered why I couldn't turn the engine over by-hand in the stand. Turned out that one lifter was being lifted by two cam nodes, so cr*p was the grind. Genuine cam went in, but stupidly I didn't also junk the britpart lifters and I can already (6 months later) hear one being a bit sticky at idle.

IMHO ARP mains studs are worth it even on a standard engine if the block's not cross-bolted - almost all blocks I've come across the main bearing caps have been pretty loose for a supposed interference fit. ARP studs help stabilise that a bit, plus it's just nice to use what are obviously top-quality bits of kit :-)

Cheers,

AndyC.

[Bull Bar Cowboy]

From here http://www.realsteel.co.uk/ the OEM cam is £59.00 and OEM lifters £48.76 per set (£107 total)..... however, you can get an OEM cam from a third party LR parts dealer for £49.00 ...... sh!tpart never were never OEM...........the above is just n example ......... you can get the cam + lifters trade for a little over £75.00

I find your comment about two lobes lifting one follower a bit mystifying ......... the grind would have had to be so bad that it would be blindingly obvious before fitment ! ............. also a cam should never be changed without new lifters, and it also needs to be run in correctly (2200+ rpm for 20 minutes then an oil change)

[zoltan]

You would be surprised at how well a 3.5 can be made to go

However, in your position I would go for a secondhand engine of higher cubes, regardless of condition, an use that for the basis of a rebuild .......... in that way you end up with a more relaxed motor rather than a potential highly stressed 3.5.......balancing is not required unless you are using it for racing ..........most V8's balance out reasonably well from stock ...........just match lightest piston to heaviest conrod etc......

Its well easy to spend a load of cash in not achieving much gain for the average user ....... not like track engines where every single hp /ftlb counts big time.....

However,unless you are going for some serious performance parts then the pricing is a little adrift ………. to rebuild a 3.5 to OEM spec I would be looking at about £800 - £900 in parts & machining…………

Rebore + Crankgrind £300

Heads shaved 20 thou £ 30

Set of SD1 Pistons + Rings £170 (includes Machine shop pressing pins)

Cam + OEM followers £100

Big ends, Mains, Timing Gear, oil pump etc £100

Rockers + Shafts £120

Gaskets £50

If you then want to add in the goodies ………..add these in above OEM

Road Cam £ 75

Bleed down lifters £ 65

Cloyes Timing Gear £ 85

Head Machining £150 (valve guides lined ,shortened & seats cut)

ARP studs top + Bottom £200 (not needed unless you are going to 'use' the engine to its max ability

I get £1245 from your figures, not including ARP bolts. I've been offered two options on pistons: some 9.35 compression Hepolite or 9.75 Taiwanese sourced. LPG seats adds £150 on my quote and the Far Eastern pistons are worth £275.

I hear what you are saying on a high cube engine, I'm strongly leaning to using my 3.5 project engine and source something for the project later on. I definitely don't want to inherit someone else's cooling problem which is why I've opted to build it myself.

I know my way around engine builds from work but its somewhat easier when you are spending someone else's money!

Plus its a bit of a busman's holiday and I'd rather be doing other things in my free time, there is no great magic for me building my own lump aside from knowing what is inside and knowing it is right.

I was going to throw a bid in on Rogers 4.6 but he sold it early on

Following that line of thought, many of th 4.6's suffered cooling problems, are the cross bolted Coscast engines *that* much better?

[Andrew Cleland]

From here http://www.realsteel.co.uk/ the OEM cam is £59.00 and OEM lifters £48.76 per set (£107 total)..... however, you can get an OEM cam from a third party LR parts dealer for £49.00 ...... sh!tpart never were never OEM...........the above is just n example ......... you can get the cam + lifters trade for a little over £75.00

I find your comment about two lobes lifting one follower a bit mystifying ......... the grind would have had to be so bad that it would be blindingly obvious before fitment ! ............. also a cam should never be changed without new lifters, and it also needs to be run in correctly (2200+ rpm for 20 minutes then an oil change)

Sorry if my comment sounds sarcastic - I was actually really wanting to know where I could get an OEM cam for that price.

Anyhow, I buy lots from Real Steel, but I wouldn't call their standard cam OEM - it's no more expensive than a Britpart one, so I expect similar quality (it may even come from the same factory as Britpart source theirs - there can't be that many people grinding standard spec cams for the RV8 now). Certainly all the cams from Paddocks, Craddocks, Beamends, etc. around the £50 - £70 mark are Britpart.

The problem I had with the cam was two nodes were slightly, about 20thou, too close to each other - you wouldn't pick that up just looking at the cam but once it's in the engine and lifters in place you can see one lifter being lifted by not only its own node but the one next to it also snagging on it as it comes around. I have photos somewhere but can't fine them at the mo.

Where I was stupid with rebuilding this engine is after finding the problem with the cam and putting in a genuine parts one, I didn't also take out the (new) Britpart lifters and put in genuine parts ones. On top of the normal bedding-in procedures for the cam I like to add a bottle of Competition Cams bedding-in lube to the oil - apparently it puts back slippery stuff that modern oils have taken out.

Getting back to Zoltan's original question, I'd go the route of rebuilding an engine I know (which I've done for three different V8s now). Yes, the cost of a rebuild will buy two or three V8s from the scrappy, but for me it's more the inconvenience (and to be honest, the embarrassment) of having an engine let go that makes the rebuild route my choice. I guess if you're looking for an engine for a weekend toy then you can be less picky, but all mine go in daily drivers which also make 1,000 mile plus journeys every year (I have a special savings account for holiday fuel...) - I don't want an engine giving-up halfway to Italy with the family in the back.

The most recent rebuild (the one with the dodgy cam) is a 3.9i, ex Range Rover, from 1993. I know the block is basically sound and hasn't shown any sign of dropped liners/porosity/etc. I had it re-bored 20thou over, mains honed, new cam shells fitted and honed. New pistons (Real Steel, standard CR, 20thou over) and ARP studs on the mains. Cam is genuine parts 3.9i, Real Steel heavy-duty pushrods, steel rockers, new valves, springs, seals (all Real Steel). Head skimmed 20thou and tested for flatness, genuine parts composite head gaskets, ARP head studs (overkill for this engine, but I got a deal on mains + heads). The rest is pretty much stock apart from a Double S stainless exhaust (which doesn't really fit properly) & a Rimmer Bros stud kit for the exhaust manifolds. Injection is standard 14CUX and ignition is a standard dizzy with Magnecor leads. Future plans are either Megasquirt or VEMS, primarily for dizzy-less ignition, but also looking at port-injected LPG & a general tidy-up of the engine bay wiring. All this is in a 1994 110 station wagon btw.

Cheers,

AndyC.

[Bull Bar Cowboy]

Sorry if my comment sounds sarcastic - I was actually really wanting to know where I could get an OEM cam for that price.

Anyhow, I buy lots from Real Steel, but I wouldn't call their standard cam OEM - it's no more expensive than a Britpart one, so I expect similar quality (it may even come from the same factory as Britpart source theirs - there can't be that many people grinding standard spec cams for the RV8 now). Certainly all the cams from Paddocks, Craddocks, Beamends, etc. around the £50 - £70 mark are Britpart.

Andy,

No, the Real Steel cam comes from a very reputable supplier in the states ....... as do all their other cams.

[Bull Bar Cowboy]

LPG seats adds £150 on my quote and the Far Eastern pistons are worth £275.

Following that line of thought, many of th 4.6's suffered cooling problems, are the cross bolted Coscast engines *that* much better?

Zoltan,

I would reconsider the LPG inserts issue ……….. I have never seen regression on a RV8 …….. even on a recent 4.6 engine that had done over 100K on nothing but LPG (blown H/gasket due to heater hose fail). The seats we in very good condition and only needed a slight lap.

BL have since very early days used extremely hard seats and that comes from the days of the A series engine that used Stellite valves …….. in fact it was always said that the only good thing about a BL engine was the head ! ………….

Yes, Coscast engines are better but not worth the asking price for a known good block .......... better to spend £500 on top hat liners.........

[Andrew Cleland]

Andy,

No, the Real Steel cam comes from a very reputable supplier in the states ....... as do all their other cams.

Cheers, that's good to know - save me a few pennies over the genuine parts cam next time around. I've been tempted by their hurricane or cyclone cams, but I'm always wary of loosing low-end torque which, for me in my 110, is one of the joys of the V8 - being able to pottle around in 3rd or 4th from 5mph to 40+

Andy.

[zoltan]

Zoltan,

I would reconsider the LPG inserts issue ……….. I have never seen regression on a RV8 …….. even on a recent 4.6 engine that had done over 100K on nothing but LPG (blown H/gasket due to heater hose fail). The seats we in very good condition and only needed a slight lap.

BL have since very early days used extremely hard seats and that comes from the days of the A series engine that used Stellite valves …….. in fact it was always said that the only good thing about a BL engine was the head ! ………….

The LPG inserts are the suggestion from the people that are boring the block and doing the crank grind. They might be taking a broad brush approach of recommending some more work for themselves as they do a lot of LPG seats on Iveco's.

Where I get my LPG they run a lot of taxis on LPG and they have tried the LPG inserts on Mondeos and reckon that they only get about another 10,000 miles over the standard Ford heads. Most of these taxis get sold on with at least 300,000 miles on them and they have been just getting exchange heads off of Ford as and when the tappet clearance disappears.

I could bore and hone the block at work but we'd need to make a fixture and to be honest, its not worth the extra work as I'm probably not going to be doing a number of blocks.

Stellite is usually used for the valve tips isn't it? The standard A series, pre unleaded just ran the valves straight into the cast iron.

[Bull Bar Cowboy]

Stellite is usually used for the valve tips isn't it? The standard A series, pre unleaded just ran the valves straight into the cast iron.

True, but that is where they got experience to get it right with the the RV8 as a RR application .......... incidently the whole valve on the A series 'S' engines were a Stellite alloy..........

The machine shop I use is in winchester ..... very, very good quality........ I can pm the detail if interested.