Another 7AGE project

[peter møller]

As some of you know, i´ve been messing about an engine rebuild these last couple of months.
But it seems that finally, it is coming together.
I would really appreciate any input you all might have concerning my selection of parts, and thoughts on things i could do differently.

Parts so far...
7AFE bottom end from an Avensis, so late model engine.
Full balance of all internal parts
4AFE flywheel
Redtop pistons and rings (OEM)
Redtop head with modified intake manifold.
TOGA Race bearings
TOGA high volume oil pump
Illegal Garage clutch and pressureplate.
Schrick 258 cams.
Fidanza adjustable camgears.
ARP pressure plate bolts
ARP head bolts

This is a Torque setup, therefor i have not removed weight from the flywheel.
I expect it to be a fairly low revving engine apprx redline at 8000rpm

[S.K.]

Here is also 7A-GE in AE92 LB, text only in finnish: http://www.vhtracing.com/7atuning.htm

...Timing belt is from Porsche 924S, tensioner pulley from 7A...


E-mail: [email protected]

[NoHachi]

What I don't get is the 8000rpm part...that is astronomically high for this engine geometry..Are you doing anything to reduce the stresses to the crank and rods? Lighter rods and pistons?

The high pressure oil pump is a good addition..The whacky rod to stroke ratio will introduce a lot of extra lateral stress on the cylinder and cylinderwalls. That means a lot of extra generated heat that needs to be carried away. I would be very cautious about running very rich mixtures for any sustained time periods to try and minimize bore wash. Having the cyl.walls coated would be even better.

The ARP bolts would be a bit overkill I think..you wont be running very high cylinder pressures. Fresh OEM ones would be fine.

[peter møller]

NoHachi Wrote:What I don't get is the 8000rpm part...that is astronomically high for this engine geometry..Are you doing anything to reduce the stresses to the crank and rods? Lighter rods and pistons?

The high pressure oil pump is a good addition..The whacky rod to stroke ratio will introduce a lot of extra lateral stress on the cylinder and cylinderwalls. That means a lot of extra generated heat that needs to be carried away. I would be very cautious about running very rich mixtures for any sustained time periods to try and minimize bore wash. Having the cyl.walls coated would be even better.

The ARP bolts would be a bit overkill I think..you wont be running very high cylinder pressures. Fresh OEM ones would be fine.

As it turns out....'ARP bolts are a "no-no" for the 7AFE bottom end, they have to fabricated on the factory on order, so I have put that aside.

Regarding the RPM´s i have to say that in all honesty, i never expect the engine to go much above 7500rpm, but i have decided to keep the rev limit at 8000, but i may change that to 7500.
I have been told to be careful with RPM´s on the 7AFE bottom, but i have seen several previous builders easily doing 7500 and above without any disasters done, and thats on a quick, swap, where i have spend time balancing everything. But still.....weight hasn´t been reduced, only balanced.

[peter møller]

Oh man.....it´s been some time now.
UPDATE: Engine is being put together as i write, but i still need a few glitches to be fixed before assembly. Unfortunatly, i did not take the old 7afe apart, and therefore, i have some issues, on how to put it back together correctly.
But i have confidence that things will turn out OK :-)

[peter møller]

UPDATE: Bottom end finnally finished, now only awaiting the head to arrive from rebuild. Nothing fancy done to it, just the odd polish, valve cleaning and new packings.

What does the experts think, will an OEM headgasket suffice, or do i need to go TRD/HKS metal thingy?

[robokill]

well the headgasket is having the pressure from the pison so the room where the explosion takes place.

Seing the shop now offers trd head gaskets I would take a 0.8mm trd head gasket. But I would not believe a standard 4age toyota headgasket wouldn't make it.

[jamiemirror]

IMHO use OEM MLS 7AFE gasket.

[KrizKH]

OEM gasket should be fine whether you use 4age or 7afe, but they are not the same thickness so it depends on compression ratio..

[peter møller]

Yep....i´ve been looking at either 0.5 or 0.8mm gaskets from TRD. They are not really that expensive.
Like $75 from p.a.s.s rascing