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My turbo'd B6 has fluctuating oil pressure and has puff's of blue smoke when taking off in 1st gear (not all the time, perhaps 50% of the time). With those signs I'm thinking a rebuild is in order... Current power is around the 160-170rwkw and the next stage will be around 200rwkw.

Engine currently has:
725cc Bosch injectors
Bigger fuel pump
ARP head studs
ARP main studs
B6T rods/pistons
Greddy TD05-16g kit with a 3" exhaust

Engine was rebuilt about 40,000km's ago for 150rwkw.

I have the short nose version and would like input from proven parts that people have used as a shopping list. I'll start the list with some items:
Wiseco forged pistons 8.5:1 78.5mm
Manley H beam rods
ARP 2000 rod bolts
ACL race rod bearings
ACL race main bearings
Valve spring kit
Valve retainers
Boundary Engineering oil pump
ARP main studs
ARP head studs

Would you mind adding to this list or providing input on what has hasn't worked for your motors?
I.e. is it worth having any items balanced? Is it worthwhile porting the head? etc...

Cheers,
Ben

Why so much brand name expensive stuff?

Dann

General rule in life is you get what you pay for. If you have input into other brands or no-name brands that have worked for you then I'd be keen to hear!

Because the more it costs the better it is.... isn't it?

Recent & worth a look from midway to end if not already seen:
viewtopic.php?f=29&t=50573

Probibly not what u want to hear but id be buying a second hand long /big nose 1.6 before building a short 1.6. Just personal preference though. Sounds like a good build. will you do doing it or getting it assembled by a builder?.

Thanks for the link 93_Clubman.

Oni, I was having that exact thought this morning re a long nose. I'll need to investigate with my local road authorities if I'd be required to go through emissions testing etc all over again if I change engine numbers... I'll get on to it this week. Another alternative would be to retrofit the long nose into my existing engine.

I'll be assembling myself, but will farm out bits and pieces to workshops, such as headwork and balancing.

bark wrote:Thanks for the link 93_Clubman.

Oni, I was having that exact thought this morning re a long nose. I'll need to investigate with my local road authorities if I'd be required to go through emissions testing etc all over again if I change engine numbers... I'll get on to it this week. Another alternative would be to retrofit the long nose into my existing engine.

I'll be assembling myself, but will farm out bits and pieces to workshops, such as headwork and balancing.

If they want to get technical changing internals to lower compression, along with ther related retune would force you to re-do emissions.

In NSW you can change engine number as long as its the same engine type without recertification, I know as I've done so myself - I never listed internal engine modification on engineering ceritificates though - and had emissions passed for the original certification.

I think Dann's question is aimed at suggesting that you can build an engine capable of holding 300+rwkw without stretching the budget to high end components. A reliable set of pistons and rods can be had for sub $1k.

I'd also suggest your current engine sounds like it should handle more than 150kw - I'd be looking a cheap and easy brush hone and a set of rings before investing in a full rebuild - But I'm a cheapskate

Sean you may be right re swapping engines. I didn't list internal either so this could be a real option.

I'm also a fellow tight-ass, the combo of pistons and rods I have mentioned would be delivered for $900.

Perhaps what I ought to do is pull it out and inspect. I would've thought I'd get more than 40,000km's from a new set of rings though??

The problem with the oil pumps is the relief valve. 2 cheap ways. Use an external relief valve or have the valve flow rate increased. (each was a suggestion from different engine builders on how they deal worth the problem.)

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I don't think the big nose/short nose thing really matters in the end as long as the crank bolt is reassembled in properly. My 89 MX5 B6 never had a problem with it up to 266,000Ks when the engine died of other reasons. I assume it had the original factory crank bolt in, chances are the mechanic re-used it for the second timing belt service.

My Familia GTR with the BPD engine suffered the crank nose wear at 165,000ks of all mileages.... About halfway to the next timing belt service. Bad luck or perhaps the bolt was loosened from the previous owner doing who knows what, I don't know for sure. Really, it can happen to just about any engine.