4agte Big port or Small port?

[mlewis]

Brought a 4age red top small port engine and gearbox for $160 off trade me as I needed sump and throttle body and will split and sell whats needed.

My questions which is better for a 4agte street driven car, with some track work on the odd occasion. Big port or Small port

Is there a major noticeable difference between the too or are they only margin able?

Current head on engine is a early big port 4agze

Any ideas and advice is more then welcome as I've only ever worked with a 20v bt

[thegreatestben]

Small port has external oil drain from head.

[mlewis]

this mean i can run oil drain from turbo to head? or those oil lines for a catch can?

[stolic]

this mean i can run oil drain from turbo to head? or those oil lines for a catch can?

Nope, it means that you will have an extra oil drain at the back of the head which drians oil back to the bottom of the block (if using the corresponding small port block) or you can direct it back to the sump in the same fashion as you would a turbo oil return. Toyota added this to prevent oil pooling in the head with spirited driving, which would lead to less oil in the sump which can cause starvation. having said that, a few people have just blocked this drain on some conversions and had no issues.. tho I'd be inclined to kee it myself.

as for your choice, I'd pick the small port. should be (slightly) nicer to drive off boost... also if I'm not mistaken, I recall reading that bigport cams can yeld small power gains when put into small port heads?? I'm sure a quick search here or google could confirm this

[Vertigo]

the small port for an average turbo project, the bigport when going to maximum power. also, if doing this, throw away the stock intake manifold and tvis, and make one that is similar to the smallport design, ie. 4 large runners vs 8 restrictive ones.

and yes, bigport cams are slightly more aggressive, so grab a pair for a bit of extra power at very little cost.

[XSVWGN]

I would keep the 4agze engine you have intact mate. your only wanting a 4agte to be street driven and not after huge power. You will be quite suprised when your setup is all up and going with how responsive it is. small turbo will spool at lower RPM and good for street use


Matt

[THA SHZ]

the small port for an average turbo project, the bigport when going to maximum power. also, if doing this, throw away the stock intake manifold and tvis, and make one that is similar to the smallport design, ie. 4 large runners vs 8 restrictive ones.

and yes, bigport cams are slightly more aggressive, so grab a pair for a bit of extra power at very little cost.

and i call bullshit to that sir makes no actual difference just slightly nicer drive , been proven , its more a placebo effect

[headshotnz]

I would keep the 4agze engine you have intact mate. your only wanting a 4agte to be street driven and not after huge power. You will be quite suprised when your setup is all up and going with how responsive it is. small turbo will spool at lower RPM and good for street use


Matt

This man speaks with experience

[Crucible]

Brought a 4age red top small port engine and gearbox for $160 off trade me as I needed sump and throttle body and will split and sell whats needed.

My questions which is better for a 4agte street driven car, with some track work on the odd occasion. Big port or Small port

Is there a major noticeable difference between the too or are they only margin able?

Current head on engine is a early big port 4agze

Any ideas and advice is more then welcome as I've only ever worked with a 20v bt

So do you already have a 4agze? Smallport ze generally give better off boost driveability having slightley higher compression ratio.

[mlewis]

Already have a 4agze but its the big port aw11 version, hearing of Matts beast, I'm looking forward to the T3 i have on it and seeing how it drives. was bidding on a cheap redtop small port as was looking a cheaper option compared to finding a throttle body and sump, but missed out on the engine and found sump and throttle for $40 so not complaining

[tsoob]

20v

[XSVWGN]

20v

sure wont complain with the power i have and im sure TSOOB will say the same with his but given you have an unopened 4agze mark (mlewis) just go with that and tune accordingly

[Vertigo]

the small port for an average turbo project, the bigport when going to maximum power. also, if doing this, throw away the stock intake manifold and tvis, and make one that is similar to the smallport design, ie. 4 large runners vs 8 restrictive ones.

and yes, bigport cams are slightly more aggressive, so grab a pair for a bit of extra power at very little cost.

and i call bullshit to that sir makes no actual difference just slightly nicer drive , been proven , its more a placebo effect

alright, ill concede that the difference between bigport and smallport porting is minimal, but it is a difference. the stock bigport intake manifold however is very restrictive.