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[aaronjb]

http://www.pngclub.com/forum/showthread.php?140521-Nova-3.2-v6-(z32se)/page22

Bejeezus that must be 'interesting' to drive!

Hmm, mine was a courtenay conversion and went through 3 bottom ends till we ran it on 20/50 valvoline racing then it held together

I'm guessing you were spinning bearings, rather than bending the crank? That seems to indicate the oiling on the bottom end is rather marginal, and it has trouble keeping an oil film with the increased pressure on the crank at the bottom of the stroke.

Perhaps a high volume oil pump or increased oil pressure (you can usually achieve that by shimming the pressure relief spring in the oil pump, though I've not taken an Omega pump apart to look..) would help there.

Clearly we're quite lucky in the MR2 world - the stock block is good for almost twice the stock horsepower before rods start to make a bid for freedom!

[cem_devecioglu]

http://www.pngclub.com/forum/showthread.php?140521-Nova-3.2-v6-(z32se)/page22

Bejeezus that must be 'interesting' to drive!

Hmm, mine was a courtenay conversion and went through 3 bottom ends till we ran it on 20/50 valvoline racing then it held together

I'm guessing you were spinning bearings, rather than bending the crank? That seems to indicate the oiling on the bottom end is rather marginal, and it has trouble keeping an oil film with the increased pressure on the crank at the bottom of the stroke.

Perhaps a high volume oil pump or increased oil pressure (you can usually achieve that by shimming the pressure relief spring in the oil pump, though I've not taken an Omega pump apart to look..) would help there.

Clearly we're quite lucky in the MR2 world - the stock block is good for almost twice the stock horsepower before rods start to make a bid for freedom!

I can bet that with that power/weight ratio most of those expensive sport cars will eat his dust

if it can stay as one piece

[Omegatoy]

http://www.pngclub.com/forum/showthread.php?140521-Nova-3.2-v6-(z32se)/page22

Bejeezus that must be 'interesting' to drive!

Hmm, mine was a courtenay conversion and went through 3 bottom ends till we ran it on 20/50 valvoline racing then it held together

I'm guessing you were spinning bearings, rather than bending the crank? That seems to indicate the oiling on the bottom end is rather marginal, and it has trouble keeping an oil film with the increased pressure on the crank at the bottom of the stroke.

Perhaps a high volume oil pump or increased oil pressure (you can usually achieve that by shimming the pressure relief spring in the oil pump, though I've not taken an Omega pump apart to look..) would help there.

Clearly we're quite lucky in the MR2 world - the stock block is good for almost twice the stock horsepower before rods start to make a bid for freedom!

yep kept knocking out the bottom end, seems to be a bit fragile on the 3litre, car was built more for torque than outright power, so boost was low at 6psi, did the job though!!

[TheBoy]

The V6 crankshaft may prove the weak link. The general concensus is its good for about 250bhp if you have the 3.0l crank.  So you are possibly going down a road that could be expensive and becomes a dead end.

Good luck with it though, and keep us informed of progress


As to the Courtney ones, I think most members here know my views on Courtney's skills and capabilities. Or lack of. 

[Marks DTM Calib]

A 3.2 bottom end would be a better option as that has a steel crank.

Add in some decent main bearings studs along with possibly a stronger steel girdle and the bottom should be fine.

As for the 5-6 pot cooling issue, would be interested to hear your thoughts on that one. Vx did make some changes around 1997/1998 around the head cooling so make sure you have at least an engine later than this.

[mike v6]

Hmm, mine was a courtenay conversion and went through 3 bottom ends till we ran it on 20/50 valvoline racing then it held together, as you say the manifolds went forward to the turbo in front of the timing cover where there is plenty of room once you have junked the multiram system which you wont need with a turbo, paddle clutch is sensible as is stand alone management,
you can junk the middle box,s with the turbo as it quietens it down, for info sierra cosworth calipers fit the standard discs, with a small bracket to mount them on, you will need to clearance the inside of the calipers at the back very very slightly, this wll give you 4pot,s on the front and greatly improves the brakes, rears can fit 3.2 vented direct replacement for standard!!
think the pics of my old one are on here somewhere!!
get some pics up of the build!!
and good luck with it !!

some good info there bud so courtenay  have done the v6 conversion what did the quailty of the manifolds look like as that might be an eayser way for me to get one what sort of mods did they do to the bottom end did they change pistons and c/r or was it standad and just bolt a turbo on and try to map around it ive looked for pics but couldnt find any is there any chance you could post some up if you still got them what was the over all power at just 6psi also what the the drivablty of it like i bet it pulled very well

[2woody]

the main bottom end problem is the oil temperature, running quite high because the coolant temperature is high. Omega has a high thermostat opening temperature for emissions reasons.

Run a lower mass coolant temperature, cool the oil externally and I believe the reliability problems will be largely overcome. Certainly no need for forged pistons, aftermarket rods or a steel crank until you're looking at the thick end of 450 horsepower. Audi S4 clutch cover will also obviate the need for anything expensive.

Aftermarket fuel management will be an absolute must, tho

there is also some stuff that could be done with the hoses around the back of the block, probably like twinning the bridge outlets into the heater through the aux coolant pump.

I'd definitely recommend two tiny turbos rather than one big one.

[Elite Pete]

Hmm, mine was a courtenay conversion and went through 3 bottom ends till we ran it on 20/50 valvoline racing then it held together, as you say the manifolds went forward to the turbo in front of the timing cover where there is plenty of room once you have junked the multiram system which you wont need with a turbo, paddle clutch is sensible as is stand alone management,
you can junk the middle box,s with the turbo as it quietens it down, for info sierra cosworth calipers fit the standard discs, with a small bracket to mount them on, you will need to clearance the inside of the calipers at the back very very slightly, this wll give you 4pot,s on the front and greatly improves the brakes, rears can fit 3.2 vented direct replacement for standard!!
think the pics of my old one are on here somewhere!!
get some pics up of the build!!
and good luck with it !!

some good info there bud so courtenay  have done the v6 conversion what did the quailty of the manifolds look like as that might be an eayser way for me to get one what sort of mods did they do to the bottom end did they change pistons and c/r or was it standad and just bolt a turbo on and try to map around it ive looked for pics but couldnt find any is there any chance you could post some up if you still got them what was the over all power at just 6psi also what the the drivablty of it like i bet it pulled very well

IIRC the bhp of the Courtenay conversion was the same as a normal 3.0 but with increased torque