Does it have to be a TVR replacement engine

[j&ms]

Just a quick look on ebay and had a look at this engine.

http://www.ebay.co.uk/itm/RANGE-ROVER-P38-4-6-ENGI...

A rover unit for around £750.

A 4.0 TVR engine from a breaker.

http://www.ebay.co.uk/itm/TVR-CHIMAERA-4LTR-1994-E...

Around £1900

Is it really worth the extra grand and is it possible to swap.

[SILICONEKID343HP]

You could start with something like this and rebuild it or get a low mileage 4.6

http://www.ebay.co.uk/itm/range-rover-P38-4-6-engi...

http://www.ebay.co.uk/itm/RANGE-ROVER-4-6-ROVER-V8...

If you have very deep pockets

http://www.ebay.co.uk/itm/Ultimate-Land-Range-Rove...

Edited by SILICONEKID343HP on Monday 2nd December 09:06

[TA14]

Only you know. If you're one of the many who never come any where near using the original spec performance and are not looking to sell your car ever then it's probably not worth the extra. If you're looking to buy the cheaper engine, have it checked over, buy the extra bits necessary, strip it down and rebuild it to a good TVR spec then I doubt you can do it for less than the cost of the more expensive engine.

[carsy]

That 4ltr tvr ebay engine is only a boggo 3.9 with a different cam in. Forget it, its daylight robbery. Go for a 4.6. You should be able to find one cheaper than the one you highlighted as well.

Always with ebay 2nd hand engines you dont know the state of them, so a rebuild to your own spec is advised.

[j&ms]

I was thinking, if I was to by an engine from ebay whether it be a TVR or not I would at least drop the sump and inspect the crank etc, take the heads off, change the cam, timing gear and clutch at least. So the extra grand would do all that. The breakers really are taking us to the cleaners for certain bits...

[900T-R]

TBH I would only consider a replacement engine if either:

1) the original engine is comprehensively shagged to the point that major parts like heads, engine block, crankshaft are scrap

2) I was experienced enough a mechanic that would consider engine removal & reinstall as a fairly routine procedure, and the engine I was buying was a cheap way to tide me over until I rebuilt the original one, or

3) I could buy an engine with a known good spec beyond what I originally had, with a known history from a trusted source at a good price compared to having an engine built to that particular spec.

In all other cases, just rebuild the one you have. As rightly stated above, you'll want to rebuild any random engine from Ebay or the breakers yard, anyway.


Oh, and a stock LR 3.9 makes more like 140-150 bhp rather than the quoted 190 so I assume that TVR's 'official' spec of ported & polished heads etc. for the 400 in addition to the TVR 51 cam is not entirely drawn from the air.

For comparison, there were two or three head to head tests of the Chim 400 and the Marcos Mantula with the std 3.9 back in the day and despite the Marcos being about the same weight or less than the Chim, it had trouble breaking 8 seconds for the 0-62 dash while the TVR posted low 5s... Bit of a difference for just a cam and better exhaust manifolds...

[Bassfiend229hp]

Have to say that I do keep looking at the 4.6 lumps on eBay and thinking they'd be a prime candidate for a relaxed "learn to rebuild it myself" project and - at the end of it - give a useful increase in "grunt"...

[Bassfiend229hp]

[quote=j&ms]Just a quick look on ebay and had a look at this engine.

http://www.ebay.co.uk/itm/RANGE-ROVER-P38-4-6-ENGI...

A rover unit for around £750.
[/quote]

That looks very tidy but they do say that it's just a stock photo and not the actual unit in question which is a bit of a pain plus no idea of actual mileage which would make it a bit of a no-no for me too...

Phil

[900T-R]

Bassfiend229hp said:

Have to say that I do keep looking at the 4.6 lumps on eBay and thinking they'd be a prime candidate for a relaxed "learn to rebuild it myself" project and - at the end of it - give a useful increase in "grunt"...

Rebuild block, refurbish your TVR heads... hey, presto - TVR 450 engine!

[Bassfiend229hp]

900T-R said:

Bassfiend229hp said:

Have to say that I do keep looking at the 4.6 lumps on eBay and thinking they'd be a prime candidate for a relaxed "learn to rebuild it myself" project and - at the end of it - give a useful increase in "grunt"...

Rebuild block, refurbish your TVR heads... hey, presto - TVR 450 engine!

Exactly - I already have a 400HC so apparently has the bigger valve heads ...

[900T-R]

HC has a 500 cam and double valve springs but std valve sizes... at least officially.

My sorted 430 makes 300 hp with the standard-sized valves, anyway...

[spend]

Bassfiend229hp said:

Exactly - I already have a 400HC so apparently has the bigger valve heads ...

Really?

[spend]

4.6 needs the front cover & sump swapping from your original, it is not compatible (no dizzy / different sump). The heads are unlikely to be as good as 70% of the TVR ones. The cam will be for a tow truck, it also has different timing chain & gear. You may well find the inlet manifold is different from your original so may need to do some re-plumbing (coolant).

Juiced up 4.6s tend to have the 4.0 pistons fitted to raise compression along with other mods to head & cam. Not as simple as folks make it sound ~ easy enough just not a straightforward swap.

[blitzracing]

The 3.9 RR units was standard fitement to the Ginetta, and yes it came in at around 160 BHP. A good part of this low power output is down to bad fueling, and just a TVR chip change pulled them up to nearer 200BHP. Add a decent cam and exhaust manifold to the stock motor and you can get TVR outputs. Certainly the TVR 3.9 heads Ive seen where not ported, althought it may have had different valve springs to suit the cam.

[Chilliman]

Back when I was looking at modding my BGT V8 I was told that the best stock heads were the 4.6 jobbies... dunno why it might be the case, or if it's correct, just remember being told it

Anyone know?

[Sardonicus]

Bassfiend229hp said:

Exactly - I already have a 400HC so apparently has the bigger valve heads ...

Nope but you do have guides drifted further into the intake throat area making things even worse than the stock 400 how is it going anyway Phil? are you on the mend? Chilliman the late proper serp 4.6 heads have got bigger ports weather this is an advantage or not remains to be seen if they did nothing around the throat area I would say the benefits of just bigger ports at the gasket face are of no benefit IMO I am not referring to the TVR Serp 450 because these alternate between having BV heads and ported or to just having BV's only or stock RR valve sizes so I am lead to believe

Edited by Sardonicus on Monday 2nd December 12:37

[Sardonicus]

Bassfiend229hp said:

Exactly - I already have a 400HC so apparently has the bigger valve heads ...

Nope but you do have guides drifted further into the intake throat area making things even worse than the stock 400 how is it going anyway Phil? are you on the mend? Chilliman the late proper serp 4.6 heads have got bigger ports weather this is an advantage or not remains to be seen if they did nothing around the throat area I would say the benefits of just bigger ports at the gasket face are of no benefit IMO I am not referring to the TVR Serp 450 because these alternate between having BV heads and ported or to just having BV's only or stock RR valve sizes so I am lead to believe

Edited by Sardonicus on Monday 2nd December 12:39

[900T-R]

10 bolt vs. 14 bolt heads? (inconsequential when you remember to torque up the four 'extras' on the older 14 bolt ones to 20 lbs or so rather than 80(? I tend to forget) - they just need to sit there to fill the holes...)

[Bassfiend229hp]

Sardonicus said:

Bassfiend229hp said:

Exactly - I already have a 400HC so apparently has the bigger valve heads ...

Nope but you do have guides drifted further into the intake throat area making things even worse than the stock 400 how is it going anyway Phil? are you on the mend? Chilliman the late proper serp 4.6 heads have got bigger ports weather this is an advantage or not remains to be seen if they did nothing around the throat area I would say the benefits of just bigger ports at the gasket face are of no benefit IMO I am not referring to the TVR Serp 450 because

Just going by what I was told when the exhaust gaskets were done - that the heads had either been heavily worked on at some point and that the ports had been significantly opened up or that they were likely to be originally a set of 500 heads. The file of receipts goes back years and I couldn't find any head work in there so I'm presuming (probably incorrectly then) that I'd just got the bigger valved 500 heads ... Hell, there seem to be so many Friday afternoon / Monday morning variations who knows.

[macdeb]

Bassfiend229hp said:

Exactly - I already have a 400HC so apparently has the bigger valve heads ...

Sorry bloke, don't mean to piss on your fireworks but I doubt that.