Using 5A CAM on 7A block

[normality78]

Guy's

Im not sure is my fren sh*t me out. Recently he just got his Ae111 "upgrade" to 7A block (frm 4AFE) with 5AFE head. He told me reason using 5AFE head is due to bigger port inlet and higher cam lift. Can anyone tell me is he bullshiting or what?

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EDIT EDIT....

I've checked its only the 5AFE cam but not the head.

[Joshstix]

I don't think you'll find much info on it here as we never got the 5AFE, plus we did get decent engines so nobody really bothers playing with the FE's.

In general it is quite a common thing for people to use heads fro ma smaller engine of the same family, usually in order to get more compression from a smaller combustion chamber. Sometimes an older head also has better performance potential due to less restrictive emissions controls.

[normality78]

gee... tks for the effort

[Sam_Q]

we never got the 5a engines? I saw one at a self serve wrecker 45 min ago???

I had a look at the manifold shape and it didnt look special

[Vios-GT_07]

what do the 5A come in? holden Nova or something?

i was told the 4A-F heads can be ported for significant flow.. and if you can get the cams reground, it can outflow a GE head.. but don't quote me on that as i believe there's just flow flow, and volume flow..

[Grega]

bill sherwood had some very interesting things to say about the FE heads. as per what vios-gt has said - all about flow...however the 7A cranks only have 6 bolts to the flywheel and its not a revver like the 4AGE setup.

[normality78]

what do the 5A come in? holden Nova or something?

i was told the 4A-F heads can be ported for significant flow.. and if you can get the cams reground, it can outflow a GE head.. but don't quote me on that as i believe there's just flow flow, and volume flow..

bro,
the regrind cam is the next thing i wanna do but i was being told its not reliable and safe. Any succesfull example you know for my reference?

[3sgte]

Keep in mind that there are different 4A-FE cylinder heads.
1992 model year and prior were un-inspiring, 1993 and later were the ones that are said to have potential. (note this is as delivered for North America. Old type were for AE92 series, new were for AE101 series)

It is my understanding that the 5A heads were off a 1500 CC version, and at least some of them were equipped with a tumble generating valve in each intake port for emissions reasons (lean mixture type?). I am not so well versed on the 5A, so there are likely versions I am unfamiliar with. I will do some digging...

Generally, I would doubt a 5A head is especially or uniquely desirable.

For A series -FE cylinder heads the main (huge) difference is the old vs new type.

Assuming that you can find suitable pistons, the best choice in my opinion would be a G type cylinder head.

[normality78]

actually what my fren said didnt bother me much except the valve lift. Coz all the while i wanted to do something with my cam.

don't ask me go for GE head. i do have my reason why i wanna stick with FE. lets not have another argument between GE and FE head

[3sgte]

I don't believe we have had an argument before.


What are you comparing the 5A head to?
There are a few different considerations in a comparison. The first is to confirm what you are comparing, and confirm what your buddy was comparing.

Unless we know this, we are going to be talking in circles.

[Mr Revhead]

this was answered for you on toyspeed.

as i pointed put there, it wont work, the bores are about 3mm different

[Vios-GT_07]

bill sherwood had some very interesting things to say about the FE heads. as per what vios-gt has said - all about flow...however the 7A cranks only have 6 bolts to the flywheel and its not a revver like the 4AGE setup.

and yea i didn't want to name any names, but yea Bill Sherwood aka Billzilla was who i was referring to regarding the FE heads..

as for a cam regrind, well if you're going to grind everything off to achieve 320 degrees, it'll definitely not be reliable, both for the structure of the cam-shaft and lobes, and also reliable in a sense you won't be driving the car for everyday uses.. AFAIK cam regrinds are very limited as to how much you can actually regrind, and customizing cams is something very costly and really not worth it for a FE head.. not to mention, the limit of the head with regards to size of the camshafts ...

the main question you were asking was "does the 5A head have bigger ports and higher cam lift" .. i assume you're comparing with the 7A engine.. i don't know, but you can measure it with a measuring tape.. same with the cam-shaft... port size is only as important as the volume of air it can flow..

[Fred_SPb]

5A-FE is a smaller version of 4A-FE. In Japan 5A-FE was installed on Corolla/Sprinter, Carina (T-170, T-190, T-210). It has cilinder diameter 78.7 mm, 4A-FE and 7A-FE have cilinder diameter 81 mm. So the head gasket are different, and I don't sure that is the proper gasket for this hibrid engine (7A block and 5A head).

valve spring height
5A - 42.4 mm
4A, 7A - 38.5 mm

Inlet valve cam
5A - 41.8 mm
4A, 7A - 42.7 mm

Exaust valve cam
5A - 42 mm
4A, 7A - 42 mm

Best way is to make 7A-GE (7A block and 4A-GE 20v head) , but this engine have rev problems

[Vios-GT_07]

^^

+ rep... and all the way to Russia

what's the inlet valve cam measurement, in mm? degrees of cam-shaft duration?

and yea 7A-GE having rev problems? did you mean doesn't rev as high and hard as a 4A?

[Billzilla]

what do the 5A come in? holden Nova or something?

i was told the 4A-F heads can be ported for significant flow.. and if you can get the cams reground, it can outflow a GE head.. but don't quote me on that as i believe there's just flow flow, and volume flow..

Yes it's me that's doing one up.
I'm expecting about 240hp from it.
A mate of mine in Holland has built an almost identical engine and it makes 248hp at 9000rpm. My engine has larger valves, a better head, a little more capacity, but less compression and smaller cams.

There's three basic types of FE heads - the really crappy common one, the reasonable twin-port one, and the very good & rare Japanese one.