4age Crank Info for 4agte usage

[Shakotan_Aaron]

picture doesnt match the descrption lol. (note the 7bolt crank)

[dangdang]

I imagine most forced induction 4a's wont be revved past 8'500, or dont need to be to reach high power levels.

Cast sumps and main cap ladders like tomei's are mostly quoted as helping with engines up to 10'000 N/A.

I guess it may be block deformation at those high rpm's which leads to crank failure.

Question is does this deformation happen so much at the lower 8'500 threshold I will be running, even with 20psi+ ?

Just considering the Tomei ladders. http://www.tokyoseven.com/T7/product...oducts_id=1340

[Shakotan_Aaron]

i was under the impression that it was more the alloy sump expanding at a different rate then the cast iron block as iron and alloy have different thermal properties.

[dangdang]

Doubtfull, formula atlantic engines ran alloy sumps for years, the expansion difference would be negligble surely? As weighed against the stiffness advantage!

Some of the failures from running an alloy sump would surely be problems in the dry sump system?

Are there "wet" alloy sumps available?

Crank ladders anybody??

[dangdang]

[QUOTE=In the end I just bought a new 20v crank through Toyota NZ which came from Japan. Cost around the $560 mark delivered.[/QUOTE]

Hmm looks like the local co-op Toyota parts department is getting a call 2moz.

[Sam_Q]

I imagine most forced induction 4a's wont be revved past 8'500, or dont need to be to reach high power levels.

Cast sumps and main cap ladders like tomei's are mostly quoted as helping with engines up to 10'000 N/A.

I guess it may be block deformation at those high rpm's which leads to crank failure.

Question is does this deformation happen so much at the lower 8'500 threshold I will be running, even with 20psi+ ?

Just considering the Tomei ladders. http://www.tokyoseven.com/T7/product...oducts_id=1340

it wouldn't as the force on an engine is to the square of the revs, so 8500 revs is pretty relaxing compared to 10000 with or without boost.

[TERRA Operative]

I'm not sure how effective the ladders will be as they are just adding a little more metal to an already meaty cap.
If there was a way to install four bolt main caps like on the American V8's, now that would be interesting....

However, I've never seen a 4AGE drop a main cap? Then again, I'm not familiar with the 4AGE beyond 8000RPM.

[Sam_Q]

there is a worklog in here on one of the other forums of a formula atlantic rebuild and his midding crank bearing was in 2 pieces, still ran fine funny enough

[dangdang]

Ok after much piddling around and not being able to find a second hand crank shaft anywhere I had pretty much resigned myself to the fact that I would buy a complete smallport, swap the cranks and then either utilise or sell the engine to get my money back, bit of messing around really.
Then I pulled my finger out and rang Toyota for a price on a new one....$550 delivered!!! I nearly fell backwards, very surprised I expected it to be more like $1000 plus. Also on the recommendations of another forum member I'm getting a quote from Amayama, see if they can do better. I should have listened when Dongaz said he got one from Toyota NZ which came from Japan for $560 delivered. This way it will be a brand spanker and probably from the blacktop production run that had tighter tolerances and balancing.

[30psi 4agte]

30 psi...... 9000 + rpm.......... 313 rwkw .......Std crank........ nuff said.........

[trdee]

30 psi...... 9000 + rpm.......... 313 rwkw .......Std crank........ nuff said.........

what pistons and rods do you run mate?

[RT40Corona4AGTE]

GZE pistons and aftermarket rods I think...... cant go past GZE slugs!

[Casey-G]

Has anyone read the NZ thread?

Std silvertop bottom end + gze slugs with a black top head, massive donk turbo 32.5psi

made something crazy like 360kW on a stock bottom end.. i think cranks are the least of peoples worries when pushing these motors

[allencr]

30 psi...... 9000 + rpm.......... 313 rwkw .......Std crank........ nuff said.........

30psi 4agte, does 'Std crank' also mean that it hasn't been ground undersize, and, would you hesitate or avoid using an undersize crank like the OP??
Thanks.

[dangdang]

30psi 4agte, does 'Std crank' also mean that it hasn't been ground undersize, and, would you hesitate or avoid using an undersize crank like the OP??
Thanks.

Exactly allencr! It wasnt that I was saying the standard 4age crank was no good it was just that the one I had was ground undersize
and I couldnt use it for my application, I had read so much conflicting crap and I wanted to know the replacement was the correct part.
Turns out Mr T never really changed the p/n for a reason! Like most our cars themselves it nigh on indestructable lol. This thread has
brought together a lot of info, mostly based on good solid experience, keep it going! Theres a reason a 4age crank is only $550 dollars
from Japan.........cus no ones ever broken one....