Building up a mean F head

[Sam_Q]

I am looking at getting a later model F series head and ditching my modified 20v blacktop head to go for it. While this will very much confuse some people, but others will know what I am talking about.

I want this to be a combined information thread on the xAF series of head


I would very likely do this setup for myself if I dont change my mind once again:

- Make my own manifold to hold ae101 quads and injectors probably under the manifold
- airbox with curved inlets from a low mount design
- ports massively changed to have good flow characteristics
- redesign the cooling system to RWD form to much like my 20v guide I wrote, it its possible that is.

there are 3 main F series head as pointed out by Bill Sherwood, we got 2 here in Australia and are as shown (stolen from wikipedia)

http://en.wikipedia.org/wiki/Toyota_A_engine




this one is the earlier 4afe type head and I have also seen on a 6afe, this was made in 1987 to 1992 and from what I hear this isn't much good from a peformance viewpoint.



Then theres the second engine:



This was made in 1992 to 1998, and if I am not mistaken it was available on the 4,5 and 7afe. This is the head that was available here and is meant to have good tuning potential in atmo form.



Here is some pictures of the internals I have taken off this website in denmark:

http://www.sitecenter.dk/starletgti16v/toppti/


the combustion chamber: apart from deshrouding what should I do to it?






heres the intake with its weird swirly thing that toyota introduced. I also included a pic of how the guy oppened it right up. Should I also grind back the valve guide or does that have negative consequences?








The exhaust ports intermediate and after from what this guy did




I will try and contact this guy and possibly use my german friend as my germans a lost cause these days.



I want to know anything people have found on here if possible.

Bill Sherwood: I would like to get your information on here shortly


I will also try and get info from other threads moved onto here

[Sam_Q]

from another post located here:

http://www.toymods.net/forums/showthread.php?t=26216

time to copy posts across

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.

Yeah the twin-port TVIS ones aren't too horrible. They need a lot of work around the bottom of one of the ports though, as Mr Toyota has added some weird swirly thing in there. And one port is smaller than the other as well.

Billzilla,
currently this is what im trying to do.

stock





after





But for the 7A I'm building in Malaysia, it has to have a stocker (from the outside) manifold so I was stuck with it, and I removed the ribs between the ports as I wanted to get the inlet runners as short as I could and it'd also give a little more volume to the plenum.

[Grega]

hmmm. following this with interest sam.
i have a 4AFC in my ae92 ; looking at the 100 killer watt conversion but just holding off that wee bit...
if u need anything measured off that let me know

[Sam_Q]

yeah thanks for the offer however I have an ae92 at the self serve wrecker near my house. So the engine you have looks like the first picture yes? you may be able to get the later model head, modify it and put it back on. The ecu will probably be very limiting though.

[fixeruperer]

they made the early head to 1994.
im leaving my 4afe standard but wouldnt mind how they go if they were to get done up.

[Hen]

If you haven't already found it there is a thread on the old forums titled "4A heads, F vs G" or something similar. Has some good info on which F head is the goods. Late single port (non-TVIS) is what I seem to remember.

I have no doubt your Danish contact speaks excellent English, however if not I can translate Danish if needs be.

Hen

[cam_ra40]

That's my mates inlet Manifold up above. I can give you his details if you want more info on what he went through.

[Sam_Q]

fixeruperer: thanks

hen: thanks i will look into it

cam_ra40: that would be great

[Sam_Q]

found the link, i will scour it and post a summary on here

http://forums.toymods.org.au/index.p...5b79f24630f077

[Billzilla]

Righto.
I really need to get mine together before anyone builds one first!
I've got most off the bit I need but I'm just waiting for the con-rods. They've literally been on order from a Sydney company via a friend of mine for well over a year. I won't name them - yet - as I don't want my friend involved.
I still may cancel the order and go somewhere else.

Anyway, I'll answer some of the stuff you want to know, but maybe not all of it as I've got quite a lot of work invested into getting this engine right, I'd rather not just hand it over sorry.
Stuff like the piston tops - my secret sorry.

Anyway I reckon they're a pretty darn good head but still need a lot of work to be excellent. More work than a G head, but the end result will be better.

[cam_ra40]

In South Africa they got the 4afe for much longer than us. here is a pic of the inlet manifold on their 2001 model version. It looks like it would be the best flowing in stock form but muybe not as much potential as the modifyed one above.

[Sam_Q]

bill: I think the way I build things is simular to you, afterall I first asked you a sprinter question 8 years ago now I think, hard to remember. So I like your chances of finishing it first.

So did you end up going for the 4340 rods in the end? or the titanium ones? I remember the post a while back when you were asking about the fatigue limits of them.

As for the experimental part of your engine I am tottaly fine with that and respect that. You earnt that information and I think its very unshelfish to even show anyone at all about the potential of the F head instead of hiding till its done. Now that I am gratefull for.

So I do have some questions that I dont mind you being as vauge as you want

- not that it matters but that pic that ra40 man has supplied to us is that the same as the rare jap version?

- I will likely use 16v ae92 pistons, would that work ok? I am guessing using my silvertop pistons is a bad idea, and yeah I know I am rough

- apart from some seriousc deshrouding of valves is there anything else I should do? (dont answer if you dont want)

- also your friend could he possibly have the most powerfull 4a atmo engine anywhere? if so that would be so ironic


cam_ra40: thanks for the pic, pity I cant get it here, even if I could it would end up costing heaps. Just curious how do you know about this is that part of the world?

[cam_ra40]

ra40 man haha bit of an unfortunate name since i've owned about 5 much nicer toyotas since those days.

I got hooked on a South african toyota forum a while back when i was looking from some TAZZ (2006 model ae92 for those who don't know) tail lights from my ae92. 4ages are rather hard to find over there so modifying the 4afe is quite common, this inlet manifold is the one of choice.

[Sam_Q]

oh interesting, and yeah there was a guy on this forum a few months back that said he had a tazz, much to people confusion, I think it looks ok.

[Billzilla]

So did you end up going for the 4340 rods in the end? or the titanium ones? I remember the post a while back when you were asking about the fatigue limits of them.

I went for the titanium rods, but I'm really sick of waiting. I'm likely to cancel the order before the end of the weeks and take my money elsewhere. They'll be steel rods but I'm more than happy to have a little extra weight there.

- not that it matters but that pic that ra40 man has supplied to us is that the same as the rare jap version?

It looks different, I haven't seen that one before.

- I will likely use 16v ae92 pistons, would that work ok? I am guessing using my silvertop pistons is a bad idea, and yeah I know I am rough

They'll be fine, about the bet stock piston you could use. A little heavy, but okay otherwise.

- apart from some seriousc deshrouding of valves is there anything else I should do? (dont answer if you dont want)

That will help a lot, though don't reduce the squish areas too much.

- also your friend could he possibly have the most powerfull 4a atmo engine anywhere? if so that would be so ironic

Well someone has to! I guess it's possible, as it's more than the power claimed by the Formula Atlantic engines, and that was with US horses which are smaller than real horses.