4agze 4afe head.

[Bazda]

Measure it if you have lots of these heads lying around.

Cut some clear perspex out, drill 2 holes in it, measure the amount of water you fill it up with.

[mega4a]

Measure it if you have lots of these heads lying around.

Cut some clear perspex out, drill 2 holes in it, measure the amount of water you fill it up with.

yeah was thinking that or plastersen or something but cbf tbh lazy saturday.

ummm im thinking anyway if i use the older pistons with the -10.37cc dome.
itll be low compression anyway

[mega4a]

okay update...

motors together bored oversize 0.50 over for bigger dished pistons =0 acl performance bearings mains and big ends, 4agze crank shaft and rods and pistons and flywheel all balanced. trd head gasket 4afe head fits on no worrys. new clutch and wiring the megasquirt and we away.

[Flannelman]

Bazda - nice work on the headwork.

Just my $2 worth, manifold psi from a turbo is simpily measuring the restriction between the turbo and the intake valve. Reducing the restriction by increasing headflow is far better idea than trying to increase boost through a restrictive head.

Thats not to say the restricive head wont work. If the correct turbo is applied, it will create more torque earlyer and have more midrange without the insane topend of the high flowing head. Massive horsepower wont be created, yet it will be far more controllable especialy in wet weather.

[gt4dude]

it will create more torque earlyer and have more midrange

yet it will be far more controllable especialy in wet weather.

low end torque, fwd corolla, more controllable in wet weather? heh...

i'm no scientist, but i should think with a FE head turboed, you wont really get any earlier torque than a GE head with the same setup, the only thing you'll get earlier is a choke point...

turbos flow a fkload in their efficiency range, so limiting the head and the cams and all that, isnt going to bring the turbos efficiency range down so all your doing is mismatching the turbo and give u a narrow usable power range between 4000 and 5000, because if you do get the right size turbo like a t25 or something, you're going to make dismal power. (sounds sick, goes nowhere which is the worst, everyone will wanna race u and theres nothing u can do but get ur ass handed to u)

not to mention , NA heads are cammed for overlap , a free supercharging for an NA, and a way for boost to get blown right across the head and straight out the exhaust, or even possibly if you have a poorly designed manifold, you can fire exhaust pulses straight into the opposing intaking cylinder

[MAGN1T]

not to mention , NA heads are cammed for overlap , a free supercharging for an NA, and a way for boost to get blown right across the head and straight out the exhaust, or even possibly if you have a poorly designed manifold, you can fire exhaust pulses straight into the opposing intaking cylinder

What a load of shyte.

So what you're saying is that vtecs don't work with turbos, neither do mivecs? nor anything that's a hot N/A and turboed.
What an amusing read?
Same as what you read on US based forums.....not to be taken seriously.

The better your head flows, the more HP/torque you'll get per pound of boost. So effectively you can use a smaller turbo that comes on sooner and doesn't need to make so much boost to make the same power.
Have you never heard the old saying "all the power is in the head"

Steve

[KinLoud]

4afe head combustion chamber. My best estimate is 31.5cc based on calculation from other measurements I have made.

I think 4afe head plus 8.9 gze pistons with 1.25mm gasket will have 9.8 compression ratio
With 8.0 gze pistons I think it will be 8.8 compression ratio

Ken

[gt4dude]

not to mention , NA heads are cammed for overlap , a free supercharging for an NA, and a way for boost to get blown right across the head and straight out the exhaust, or even possibly if you have a poorly designed manifold, you can fire exhaust pulses straight into the opposing intaking cylinder

What a load of shyte.

So what you're saying is that vtecs don't work with turbos, neither do mivecs? nor anything that's a hot N/A and turboed.
What an amusing read?
Same as what you read on US based forums.....not to be taken seriously.

The better your head flows, the more HP/torque you'll get per pound of boost. So effectively you can use a smaller turbo that comes on sooner and doesn't need to make so much boost to make the same power.
Have you never heard the old saying "all the power is in the head"

Steve

Load of shit? The real load of shit is people who swap out 3sgte cams for 3sge cams as a performance upgrade.

Nowhere does it say in my post that it doesn't work at all, simply implying that it's not the best for it.

So what are you disagreeing with? Valve overlap? NA cam tuning differing to turbo cam tuning?? Or are you just trolling.

[MAGN1T]

Any cam that works in an N/A situation also works in a turbo situation. It's just that factory turbo cams tend to favour low RPM torque rather than high RPM power.
The boost blowing out the exhaust just doesn't happen, that's because the exhaust pressure rises with intake pressure unless you're idling, idle is the main problem for hot cams.
That's because your exhaust will tend to get sucked back into the cylinder. That's why there's VVT and it's other things similar.

Steve

[spencer]

^ yea agree with the BHG troll king here, plenty of huge duration cam turbo cars out there not blowing boost out the exhaust

[gt4dude]

But you wouldn't really know if you were blowing out boost, apart from a rough engine note and the wastegate would be a lower pressure zone compared to a bar of boost coming from the other way.

It's a very small window of overlap anyways, but its something.

[sergei]

But you wouldn't really know if you were blowing out boost, apart from a rough engine note and the wastegate would be a lower pressure zone compared to a bar of boost coming from the other way.

It's a very small window of overlap anyways, but its something.

1) Pressure is almost always higher in exhaust manifold than in inlet manifold.
2) The gases at those speeds behave very differently - think of viscous liquid like honey.

[strx7]

Big cams in a turbo motor + power delivery just like big cams in a non turbo. The motor can become quite touchy to exhuast back pressure especially high up the RPM range as would be expected. Factory turbo cams are specced for low end punch, just like factory turbos are sized for low end punch too.

10 years ago people said you cant turbo a big ported rotary, these days every 2nd turbo'd rotary is a bridge port

[mega4a]

when the 4afe was just standard and plus turbo it riped heaps of shit with a standard skyline turbo t3 from rb20det it spooled ropund 2000 -2500 rpm making making 2-3 psi as soon as the throtle opened. i was making bout 180hp on 8psi standard internals

now with low compression and stronger bottom end ill run a new turbo that spools the same as the skyline one and run 20psi and make 300hp =]

[mega4a]

and power to weight will be insane

[mega4a]

http://www.youtube.com/watch?v=pJCryIcoB0Q

http://www.cardomain.com/ride/653609/19 ... ta-corolla

[h8wrxs]

that corolla is seriously cool