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Finally my conrods have arrived and I pickup my replacement block next week

On the rebuild list so far are:

Pistons (hopefully ACL can do some forgies, any recommendations?)
Argo I beam Rods
Bearings (Mains & BE) and seals
Knife edge and balance crank
\"O\"ringed head
Gaskets (Mazda)
Machine Flywheel
New 5 puck organic
Thrust
Spigot

I'm homoligating two motors into one, using the head/manifolds/flywheel/ancillaries from my warm 10AE thats done 70000ks.

The donor motor has done 7500 k's but hasnt been run for 7 years so I expect every bit of rubber to be perished along with a good serving of sludge and scale.

What else should I be looking at or replacing.
Should I do the timing belt/tensioners while it's out?

Suggestions would be appreciated

BTW: aiming for a reliable 240 at the wheels

Mate if your engine is out an in bits, u mayaswel change the timing belt and water pump, as its a bastard to do engine in. Pretty much most of your seals you should look at doing too. As for your 240 at the wheels, is that kw or hp? Also, with or without forced induction?

Water pump is a good idea, thanks. Is it worth going genuine or aftermarket?

What if any seals ? (apart from what comes in a full gasket kit)?

240 is kW (currently 195kW atw), GT28, IC, 4 additional 440's & Link.
Looking at running 2 Bar, currently 15 psi, but would like more

Cheers

240Kw
OMFG

you selfish bastard Woo

195kw atw and you want more.


just kidding Woo
I guess....i would be over the moon with just an extra 20.

hope it goes well for you

Woo wrote:Water pump is a good idea, thanks. Is it worth going genuine or aftermarket?

I went genuine with my timing belt/water pump when I put in the tighe cams.
Go aftermarket if there is a substantial difference in price.
If I was to do it again, that is what I would do.
Also change the cam seals, rear main, front main and so-on.
I am not sure if the cam seals come with the VSR kit (head gasket and ancillaries gasket kit).
Good luck, sounds like your motor will be awesome to behold!

240kw on 30psi sounds about right......mine only does 154ish @ psi. Thats just boost into a 1.8 with forged pistons and rods, with 440cc injectors. Getting 30psi out of T28 might be an issue, I heard they max out around the 25psi mark, but it sure would be interesting to see what you can do. As for what seals, Im not sure of the exact ones, but when mania rebuilt my engine, they changed all the seals. Keep in mind my car had done close to 200k, so we wanted to pretty much make it into a whole new engine

I'd be a little doubtfull that the crank and rods (they are quite small rods, by the way) would live with 2atm of boost, but 240kW ATRW should be possible running around 1.5ATM if you get the head worked nicely.

Don't forget you're not talking about a V12 bi-turbo Mercedes engine (that runs 1.5ATM, about 21 lbs of boost as standard) which has BIG rods and a BIG crankshaft.
Small motors have dainty crankshafts and slim little rods, so keep that in mind when you go for the big power.

I hope by machine flywheel you are only flattening the clutch face and are not lightening a stocky. I'd hate to see a flywheel blow apart at your power levels and cut your ankles off.

You should also put in ARP studs to the head and mains. You should probably also look at modifying the oil pump pressure relief valve. You may also need to reroute your cooling system to cope with the extra heat at 2bar. Also, you are spending big $$ on argo rods, but only going for ACL pistons. I reckon you might be better looking at Flying Miatas designed wisecos if you are already going to this much expense. Sounds like an interesting exercise though. I reckon your gearbox will die quickly too - 4th gear most likely.

I would be a bit concerned that the ACL pistons may not be up to that level of boost.

Considering the amount of $$ you are spending elsewhere in the engine, I suggest that you consider some quality forged pistons from Wiseco, JE, Mahle, Venolia, HKS, etc. They all do forged, BP pistons for turbo applications (some B6 too as it happens).

****

I just checked the ACL Race series and yes they do a forged race piston for the 1.8 BPT specifically. http://www.aclperformance.com.au/MazdaBPTForgedPistons.htm

I'm using B6T rods and Wiseco forged pistons.

My rebuild's on hold til I find a new place though, unfortunately.


Did you injure your original engine, Woo?

Suppose I'm just building up a shopping list and I appreciate the positive suggestions, Cheers

The 10AE crank is balanced to start with (or considerably smoother than the NB8B I've compared it to) but will be balancing it to within a bees d!ck and then some. Many fellow engineers I've consulted (with some exceptions Benny) are confident the crank will hold for 450 kW and 600+ Nm with \"careful\" tuning. I've seen 280 kW from my motor before the crankcase and sump became ventilated using #1 conrod (does that answer your question Sabre? ).

The Argo rods are good for much more than I would want from this motor and as they are \"I\" beems they are ideally suited to large boost pressures. Argo claim if they cant handle 3 Bar they will replace them (and at $35 a rod they are putting their money where their mouth is imo).

The flywheel will only be faced CT. I've had a lot of experience with lightening and underdrive and have experienced the results of imbalance and fracture. Light isn't always the best. Having said that the combination of flywheel and underdriving can release usable torque on a stock low powered \"dainty\" motor such as the 5.

Venolia would be my first choice for pistons however they don't make a short skirt pot in the 83mm, They do however do an 84mm custom so may look into what the cost would be. Hadn't even contemplated Wiseco to be honest ! They used to have a reputation for crowning going back a few years and if they have cleaned up their act and as FM use/recommend them are another good option.

This is all good guys. I appreciate the suggestions.
Although this will be motor 150+ that I've rebuilt it's my 1st BP and it's the little bit's unique to this family of motor that I'd like to become aware of.

Is mx5UK the best/least expensive place to get genuine bit-n-bobs (eg. gaskets, belts, seals)?

Cheers
Wòó

The Argos should be fine for your application. I'd only start to worry if you were upping the rev limit.

A few years ago I wouldn't have touched Wisecos, but apparently they've done work resolving the typical forged slap issues, FM love them and many Miata.net users aren't reporting any slap. The $720 pricetag was hard to argue with, too.

mx5parts is a really good place to get the various parts - I got mine from there, far cheaper than any place I could have ordered them from locally.

Just beware that the FM wisecos are different than the ones you order locally.

I'd hate to see a flywheel blow apart at your power levels

CT, other things being equal, I would have thought that it would be revs that would kill the flywheel rather than power per se? What am I missing here?

greenMachine wrote:

I'd hate to see a flywheel blow apart at your power levels

CT, other things being equal, I would have thought that it would be revs that would kill the flywheel rather than power per se? What am I missing here?

Your most likely right Ed - I was just thinking about the increased acceleration rate of the flywheel at 240rwkw and the photo I saw recently of the centre of a machined flywheel still attached to the crank while the wheel had parted company!!!!