450 engine spec knowledge

[Alun Ivor]

ive been trying to work out just what has been done to the standard engine by Tvr before being fitted to my w reg 45000 mile monster, so far I think its standard crank pistons and con rods, but cross bolted??? different cam and possibly a bit of porting etc, big valves and clever seating, tming gear and thats about it, does anyone have any more than that? thanks chaps, happy burbling.

[900T-R]

Std 450 - std RR 4.6 litre which is cross bolted, according to TVR Power spec of the day 'polished, ported and balanced' heads, TVR spec cam, slightly higher compression at 9.8:1 (std RR 9.35:1), duplex timing chain with vernier gear, standard sized valves with waisted stems - that's it. Although the spec on individual engines may contain some 'special' parts like bigger valves depending on what was on the shop floor at the time and whether the customer who originally specced it was a friend of PW. .

[Alun Ivor]

thats great, ok so valves may not be BIG, really helpful thanks. why the heck does it leak so much oil but engine sounds, goes really well, does not have exhaust smoke and otherwise is very smooth, cam etc worn but not noisy, 45000 miles two owners and otherwise is a lovely example?//?

[Dodsy]

Alun Ivor said:

why the heck does it leak so much oil

Its a 12 year old car, undoubtedly some seals need replacing. My leak turned out to be the valley gasket, since being replaced she hasnt used a drop :-)

[900T-R]

Indeed, everything points into the direction of an oil leak - which should be relatively simple to trace yet can be rather time consuming - rather than the engine burning oil. Valley gasket (it's a composite multi-layer affair and when moisture gets to ther metal underneath...), rocker covers (mine had some wiring pinched between them and the heads after a HG replacement, leading to oil seemingly dripping from 'unlikely' places when looking from beneath), sump gasket are all prime suspects, and relatively easily rectified.

[Alun Ivor]

thanks chaps, right from conception these little light alley engines had gasket woes, seems they stll have, lol

[King Fisher]

I was told the crank was different on the 450 and 500s?

[OleVix]

King Fisher said:

I was told the crank was different on the 450 and 500s?

400, 450 and 500 have the same bore but different cranks. Longer stroke on 450 and super long stroke on 500

[Alexdaredevilz]

I thought the 500 had bigger bore

[900T-R]

Nope, all 94 mm. Indeed, arguably the cleverer way to get to 5 litres would´ve been a 96 mm bore x 86.something stroke (as per some aftermarket builders) rather than 94 x 90...

[haircutmike]

Out of interest, how does JE get 5.2 and 5.4 out of the block?

[Ant.]

As said, all the same bores from 3.9 to 5.0.
The larger capacities have top hat liners bored to 96mm and then crank stroke to suit.