4.2 crank

[Oz2]

Hi all,

Looking around at different options, and being particular about the sx looking as original as I can I'm wondering how successful it would be both power and cost increasing the stroke....I "think" if you fit a 4.2 crank and rods to a 3.5 you get the 4.2.... Has anyone done this? Was it successful and how available are the parts in the uk?
None here, I've looked:-/.

Just a thought......

Cheers
Adam

[chapperssx]

Hi Adam if funds allow I would go with a 4.3 engine bud and now you have an update ECU system, plus coupled with the S102 it wold see you into that magical 300 barrier.
I still have my old dyno print out of the 400sx some where of 274bhp and 300 ftlb and as mentioned before the old girl was still over fueling at the top end , so all things considered i think your best route is to go with a 4.3 and find a nice place in the garage to store the 3.5 lump.
Good to see your still giving her lots love lol.

[adam quantrill]

Not sure Martin I think 4.3 will be pushing it, the boost will be below 4 psi at the top end, because the S102 doesn't keep up with the engine intake.

Already on mine the boost is "only" 4.5psi with 4l at 5200 rpm. You can see it dropping off above 4500. And you can't increase the blower pulley because it would over-rev the blower even sooner.

On the other hand, I have a 4.3l block sitting around as a spare, so it would be interesting to find out what it will make ;^)

[chapperssx]

I had a friend that was running a 4.6 in a Land Rover with an S102 coupled to some cards that just broke the 300 barrier ! As a project it would be nice to see what could be achieved though.

[adam quantrill]

Sounds interesting - maybe time to start work on the 4.3 lump and get it ready.

What ECU was he running?

[Oz2]

Send over the 4.3 adam and I'll give it a go!!!

Does the 4.3 have the 88mm bore?

Any body got a 4.2 pre serp crank and rods up for grabs?

Cheers
Adam

[900T-R]

4.2 (LR)/4.3(TVR) = 71-> 77.1 mm stroked 3.9 (94 mm)
77.1 mm stroke in a 3.5 would give you circa 3.8 litres