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Discussion Starter · #1 ·
i was speaking to my uncle who has built high power engines for many years and he recommends using the block i have (4A-FE) and swapping head with other mods:

complete rebuild with performance internals
4A-GE head ported
bore-over cylinders to next size
increase exhaust diameter
((thinking of turbo/super eventually))

what does everyone think
 

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if i were you i would use a 4A-GE block and internals for a natural buildup and if your going forced start with a 4A-GZE block reason being is that stock the internals are better than the 4A-FE internals and also much easier to find aftermarket parts for
 

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Discussion Starter · #3 ·
yeah i dunno i am planning on using better internals than the gze has, also i am going to be over-boring so the pistons at the very least wouldn't fit so i will definatley look at the gze but from what i understand they are both the same block so i think i'll be able to stick with stock block and get a gze head so we'll see what happens
 

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ok..... gonna fix some things here.... AGAIN.

4afe's (at least the earlier engines) use a smaller crank, with a 40mm rod journal size.

one of the better setups you can do (and i HAD this posted on vvt-i until a mod took it down... i guess i put it in the wrong place :) ) in my opinion for a fairly reliable 4age setup would be:

early 4afe block (7 rib)
early 4age crank (pre 87)... all 4age cranks are forged
early 4age rods (40mm)... they're lighter than later years (yes, smaller.... but when a rod breaks in a 4age, it's because a bearing failed first)
aftermarket (stock bore....) higher compression pistons
smallport 4age head (maybe polished..... you don't want to port them unless well over 200hp..... and even then it's debateable if it's all that beneficial)
maybe go with a 1mm oversized valve
trd valve springs (those really aren't all that much cheaper than stock ones)
bigger cams (something around 272, maybe a littler larger)
adjustable gears
200mm flywheel (billet steel one would be nice)

then you would want to go with some sort of engine management..... i would at the very least reccomend something distributorless..... less mass on the drivetrain and easier to tune. I really plan to do something very similar to this on my next engine build (ie, my next car....)
 

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i should mention..... there are differences i the internals of various 4age's as well.

around 87 toyota changed to a larger rod journal and larger rods. they used the same head as before and same pisons..... the cams were *ever* so much smaller than the earlier 4age's

around late 89 toyota started using different internals... higher compression pistons. they changed the head, got rid of t-vis, and went with noticeably smaller cams.

the 4agze uses even stronger rods than the 87+ motors. They differed mainly in pistons other than rod size. early 4agze's had 8.0:1 and later got 8.9:1 (non US motors).

silvertop 20V's share the same crank as an 87+ motor (proven, you can rebuild the bottom with smallport bearings). Obviously different heads completely and different pistons. Slightly higher compression from the smallport. However,the rods are larger than the 87+ motors, but smaller than the gze rods.

blacktop 20V's however are quite different. I personally have never measured or taken apart a blacktop. So, sizes i don't know.... I do know, however, that toyota got smart and realized that their original idea with lighter internals on the 16V's was a good idea.... and they lightened the internals quite a bit.
 
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