4afe head on st block

Technical information and builds specifically regarding the 4AGE "1620"(16valve head & 20valve bottom end combo) and its variants.

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kidte72
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4afe head on st block

Post by kidte72 »

has anyone thought of this 4afe are all over the jy and even a rebuilt head only cost ~300 on ebay anyway i have an extra st block and might try it if i can avoid excessive work/cost....

pros about this

rowland manifolds sells both sidedraft and downdraft manifolds for this

cooling can be taken care of just as the 20v head with 16v water pump conversion

ignition can be done with megajolt jr

the FE head flows pretty well and the cams have a pretty good power band for street use if its anything like my 94 corolla...

cons
no info on it what so ever ! ! ! haha

dr.occa
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Re: 4afe head on st block

Post by dr.occa »

4A blocks are pretty much interchangeable across the board. They're all non-interference motors as well so it's all viable on paper. Benefits? Not sure on that being that the AC and AF heads don't flow better than the AG but if you're willing to massage the AF head and port match, etc...then you're bound to see gains over the factory block. You should see a bump in compression too with a ST bottom end (that includes 20v pistons, rods and crank). You'll need to see what accessory mounting brackets may need to be altered, shimmed to bolt up to the block though.

ga_goosh
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Re: 4afe head on st block

Post by ga_goosh »

i think it will work compression wise. the ST has a combustion chamber of 34.5cc and the 4afe has 33cc (i think). the compression is very managable and performance oriented. i bet it could potentially be a fun engine
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kidte72
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Re: 4afe head on st block

Post by kidte72 »

i might go for it im on the lookout for a oem down draught mani rowland hasn't responded any of my emails

kidte72
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Re: 4afe head on st block

Post by kidte72 »

weather is starting to get better again which means i can work on this again anyway i spent some time doing as much research as i can and found this

http://forum.9000rpm.co.za/viewtopic.php?id=5733

for those that cant see the link some guy in south africa i think took a 7afe head welded shut the intake side and drilled n tapped holes to use i silver top itbs anywho i have silver top itbs and from what ive been reading the 7afe head has a better design then the 4afe.

which bring me to my next question what timing belt would i use ??? and would i have to switch out the oil pump on my st block?

what i have so far st short block 16 water pump st itbs anywho i wanna make this happen just fo sh*ts n giggles and cause 20v parts are expensive n rare in my beck of the woods

dr.occa
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Re: 4afe head on st block

Post by dr.occa »

If the 7AFE uses the same cam gears as the 4AFE head (count the teeth and measure the diameters of both gears) then you would use the 4AFE belt because you're still using a 4A bottom end.

kidte72
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Re: 4afe head on st block

Post by kidte72 »

well after doing some more research the cylinder heads in corollas 95 n up are both the same the cam pulley isnt though so im just gonna stick to 4afe head will post pix once i get allparts out of storage and and get my hands on a 4afe head

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