Billet 3SGTE cranks, interest?

[-Totenkopf-]

I am trying to find someone to do billet cranks for the 3SGTE at a reasonable price. I have approached Brian Crower re: manufacturing billet 4340 cranks for the 3SGTE, however, I'd need to justify to them that it is worth there time, so I am looking to see how many people would be interested in such a product if they were doing an engine build.

Prospective cost is $1900. If I can get them to agree to make them, I am looking at doing a batch of 5 91mm stroker cranks (so that the current off the shelf stroker pistons will work). They told me they could do $1500 each on a batch of 5 (obviously + freight and GST etc as it'll probably be a bit hard to import them and not attract attention).

Benefits over using modified OEM stroker crank for stroker as as below:

Billet 4340 construction
No need to machine rod journals to 3sgte size
No need to modify clutch for fitment
Able to use 3SGTE and aftermarket (ARP) rod bolts, not stuck with the little 5SFE bolts
Likely lighter then stock crank shaft (however, I am not interested in a super light crank, my crank will have to sustain 700whp plus, I am not interested in breakages every other month). Crank weight is quite close to the centre of rotation anyway so the actual inertia it adds isn't as great as say a flywheel or other large diameter item.

Anyway, I am ears. I'd love to have an off the shelf option for billet 3SGTE cranks. At this stage there is none. If I can justify it to Brian Crower, we may realise this dream for our dirty old toyota engine.

[Celica RA45]

i would be after 2 cranks but in std size 86mm stroke and must be able to go to10,000 rpm na

[beerhead]

Sounds cool, but after fiddling with 3S and 5S motors I've come to this opinion -

I don't get why people resize the journals on a 5S crank to match 3SGTE rods now that 5SFE big diam rods are available.

Toyota did it because the rod ratio is under 1.6, which creates harmonics. This is why the camry motors runs balance shafts and makes oodles of extra power and a low rpm rattle once removed. They also increased the bearing diam to reduce friction under these rattles.


Have you ever been for a drive in a short rod and a long rod 350 chev powered car? The short rods push the torque curve down, does much better burnouts, and is better in a truck, but the long rod motor revs out cleaner and accelerates harder, thanks to the reduction of internal harmonics.

If you're going to the effort of a billet crank, its time for shelf pistons and long rods too. The block cracks in half before the crank has issues on an S motor, a UK company that works on kit cars primarily do a wet sleeve conversion on 3S blocks that are meant to make them just about indestructible, 1000HP on a stock crank...

If you're looking for 10,000rpm reliable, it's all about the oil system. FYI, the only difference between an M series BMW block (8800rpm rev limit) and a standard item is a brass oil restricter with a 1mm hole on the oil galleries feeding the head. A mates 318i, 2L stroker turbo that can match a superbike in the straights killed a pile of motors before he looked at the M series parts list and worked it out. This is the common stop my RB25 from exploding at revs mod too.

Done right, your cams get enough oil pressure, and the excess oil flow leaks straight out of the crank bearings and back into the sump, rather than filling your rocker covers with 3L of oil.

/end rant Wasn't going to post this, but I'd love to see an S motor at max potential !

[-Totenkopf-]

Sounds cool, but after fiddling with 3S and 5S motors I've come to this opinion -

I don't get why people resize the journals on a 5S crank to match 3SGTE rods now that 5SFE big diam rods are available.

Toyota did it because the rod ratio is under 1.6, which creates harmonics. This is why the camry motors runs balance shafts and makes oodles of extra power and a low rpm rattle once removed. They also increased the bearing diam to reduce friction under these rattles.


Have you ever been for a drive in a short rod and a long rod 350 chev powered car? The short rods push the torque curve down, does much better burnouts, and is better in a truck, but the long rod motor revs out cleaner and accelerates harder, thanks to the reduction of internal harmonics.

If you're going to the effort of a billet crank, its time for shelf pistons and long rods too. The block cracks in half before the crank has issues on an S motor, a UK company that works on kit cars primarily do a wet sleeve conversion on 3S blocks that are meant to make them just about indestructible, 1000HP on a stock crank...

If you're looking for 10,000rpm reliable, it's all about the oil system. FYI, the only difference between an M series BMW block (8800rpm rev limit) and a standard item is a brass oil restricter with a 1mm hole on the oil galleries feeding the head. A mates 318i, 2L stroker turbo that can match a superbike in the straights killed a pile of motors before he looked at the M series parts list and worked it out. This is the common stop my RB25 from exploding at revs mod too.

Done right, your cams get enough oil pressure, and the excess oil flow leaks straight out of the crank bearings and back into the sump, rather than filling your rocker covers with 3L of oil.

/end rant Wasn't going to post this, but I'd love to see an S motor at max potential !

Why don't people run 5S size. Well, I have run 5S size rods previously (5SFE pauter rods). My concerns with these was bearing speed at very high RPM and related oil shear.

This build I have custom length (0.25" longer) carillo rods, with FPO option, 3SGTE big end size. I think the big end size is much of a muchness. Increased bearing speed with the 5SFE, larger journal overlap and bearing surface area with the 5SFE but also more rod weight.

So anyway, yes I have custom length rods & custom pistons already. Also got custom 2.5mm OS inlet, 2mm OS exhaust valves.

Talking to BC they say a 86mm crankshaft of theres would be fine for 10k rpm. They are happy to do 1 off sets of 5 cranks. I have 3 for standard stroke 3SGTE in billet 4340 if you are after two. I am sure I could find a couple more people.

I'll let you know how this progresses.

[Celica RA45]

beer head my motor spins to 9000 rpm now with wet sump ,its a altezza 3sge motor and at the moment its pushing about 198 kws at the back wheels in na form
totenkof have you thought about going smaller in the bigends as im using 45mm bigends on my cranks

[-Totenkopf-]

I haven't, no. What size is standard 3SGE big end? This is where things start to get complex. If you want to start getting custom one off stuff the price is going to go up. I've expressed interest with the manufacturer in 5 of 3SGTE spec @ 86mm stroke and 5 @ 91mm stroke.

I have also contacted an Australian manufacturer. They want $4000 for a single crank, and are going to get back to me on a price for five, so, not looking terribly promising.

I've done 9000rpm on a 5SFE 91mm stroke crank, not for a huge amount of miles however, this was wet sump.

[Celica RA45]

std size is 48mm and im down to 45mm at the moment using mitsu bearings also using a longer rod and forged piston let me know on the price as im going to go with 86x 48mm bigends and i can custom grind thes e down later

[beerhead]

Yep, the restricter is built into the gasket on the beams from the rumours I've heard.

beer head my motor spins to 9000 rpm now with wet sump ,its a altezza 3sge motor and at the moment its pushing about 198 kws at the back wheels in na form
totenkof have you thought about going smaller in the bigends as im using 45mm bigends on my cranks

[RONA]

An updates on this, Rona may be interested in 1 x 91mm crank pending timeframes.

[-Totenkopf-]

Just about to put my order in with Brian Crower, there will be a one off patch of 5 crankshafts available. See Billet Crankshaft Group Buy for rough pricing schedule. I have confirmed with BC that it will be half payment up front & half on completion. Lead time is 12-16 weeks at this stage. Contact me via Pm or email @ [email protected] if you want further details.