Sam_Q

sure thing Paul, keep your eyes on ae86drivingclub for one of those bellhousings, the spritner drifo guys running boost should have a smashed t50 you can take a bellhousing off.

spirit: thats really interesting and it also matches up with other reports I hear and also dyno numbers. i would think that looking at the ports that a blacktop would leave it for dead but in practice its far from the case. I also think the 0.23 or so extra lift wouldnt do much on the induction side of things. ausca: they will bolt up but you will need an A to T50 bellhousing.

oh and by the way if I am not mistaken the metalic grey "silvertop" is painted while the blacktop colour is a plastic pigment instead of paint. :bash:

I have done my best to write a large part of the wikipedia entree on 4a engines so if anyone finds anything wrong please let me know. here is an article I wrote, i need to add some more of the minor things I have found since then: http://www.ae86drivingclub.com.au/faq/inde...4age/20vengines

if I get 4 orders I will machine up the backing plates for the cooling system to convert them to a rwd. The original problem still remains though that the dizzy still faces the wrong way and also the intake manifold may need to cut and rewelded hey what cars in australia did this engine come out in?

beerhead: sounds interesting, its hard to tell but those ports don't look too bad a shape from the pics

more info on a 4afe mods here: http://www.rollaclub.com/board/?showtopic=24959&st=15

a bit more info on here http://www.rollaclub.com/board/index.php?s...=25087&st=0

beerhead: I never had a good look at the 5a ports, like the 7a engine most people just make a 5sge engine out if it. Theres someone on ae86dc that has a pretty serious engine build with this combo: http://www.ae86drivingclub.com.au/board/in...showtopic=35001 Next time I am at the wrecker I will have a decent look at the head, thats assuming the intake manifold isnt too much of a pain to take off.

yeah please do, from what I got out of him: - he did the weld and grind himself - cosworth blanks where used - the engine was converted to shimless buckets (1NZ or something I keep forgetting) and he was extemely negative when I said I didnt want to just throw money at it and have everything custom. But I do think I could of done it on a reasonable budget had Kelfords not closed down. A bit of a tip for you guys I did the maths and looked at over 20 different piston designs to see whats ideal and I found the silvertop piston is the best match for its shape and dome size. The FE head has the exhuast valves protrude less out of the head so the exhuast side looks fine in terms of valve clearence even though the cutouts are 12 degrees out. So I was planning on just getting the twin valve pockets machined into the intake side, and yes it does look interesting to see 5 intake pockets in a piston. A week after I worked this out I discovered pictures from a guy in Thailand that did just this, if you like guys I can post all the pics I have found so far.

the combustion chamber would overlap the bore? as I said before though just get it bored out. If your really keen get the bores ultrasonicly tested to check the width. Of course if your not going for class rules or anything then how about just dropping the crank and rods into a 4age engine? assuming the pistons have the same deck height it should work out. The compression would be lower though because the reduced stroke would have a smaller cylender size in comparasin to the chamber size.

its all good, thanks Red

ok good idea, how about FE head for perfomance

yeah I thought about this but because the buckets on these heads so big I am pretty sure even the shims are bigger than the total bucket size of a 4age. I just thought if the 4age engines can run 10mm lift with the same diameter then I should be able to.

good question Jason, for my porting to tune the intake runners to have the right airspeed at the RPM at which I wanted I needed to significantly increase the inside diameter of the ports. Because they are a long tubular shape I was able to do this quite accurately with a set of inside dividers. So by me knowing the diameter of the ports just before the valve guide/bowl area which is the choke point I can just work out the area for one and double it (for the combined intake port area). From what I read knowing the measured air-speed on a flowbench for a given choke point is the best indication of the ports efficiency. But hey don't mistake me for a professional I am just doing my best to piece together the info I need from all sources, I could of just made a total fool of myself by what i just said. -Sam

no I quite like your open minded untill proven otherwsie attitude. I will only be getting it flow benched to equalise the port flows and not much else. However I do know the choke points of each port so I could in theory work out how efficient the ports are to a point from that.

oh and I forgot to mention the 6A has a superior valve angle for top and bottom end power, there that should stir someone up!

A flowbench gives part of the story only, if it was just the CFM then a 20v would blow everything away, the race track is a different thing. Also although the port design is tottaly superior I have to admit it takes a lot of work to enlarge the ports to whats needed to compete. I don't know for sure but I think I removed about 4 cups of aluminium filings and spend about 40 hours die grinding maybe?

well I don't off-hand know the size of the big end journal on the crank for the 4afe engine. I am fairly sure that they are 40mm which is the same as an early bigport 4age. Changing to that crank should be as simple as a straight swap and it would be a very worth-while upgrade as its a far superior model.

thanks but I don't know about that. Yes I think some decent workmanship has gone into some of it but theres way too many half finished things on it. It will be good one day, oh and move to Australia!!!

trav: a t50 would bolt straight up golberg: people are talking about this option for legality reason of the stock power figure being lower than that which requires engineering. Besides putting a 4age into a ke70 isn't that much harder than an ae71

ok heres what I have planned in the immediate future: - make a new loom up from a stock 20v loom to test my dizzy kit if it works - machine up a new crank angle sensor for my 20v head that uses a wolf optical disk and a ca18 sensor - fit Recaro seats out of a WRX - play with the suspension some more but yeah all in due time

well theres this one that I shamelessly nicked off billzillas page: other than that there was one built for a custom by road and track that was reported to have produced 200hp, this was told to me by Terry-O when I called him. as for my "build" its stuck, I don't want to pay $980 for a local weld and grind for a set of cams that might be the wrong profile. I am right now looking into getting 4age valves shortened and modified to suit the exhaust side so that it holds the bucket higher up and something custom for the inatke, this would then in theory let me grind off the base circle diameter and have some meat to grind off the cam. The base circle is a very large diamater on the 4/7afe cams so theres stacks of meat if I can get away with having a raised bucket. As for the 6a bore, I think someone needs to shine a torch down the cooling channel and see how much meat is in there. I mean I don't know much about engine/block construction but I would of thought that this block would of come out of a simular mould to that of a 4a and hence would just have extra material in the bore walls. I know this is the case for 2 to 3T engines.

well it sucks, I don't have time to do much to my car for quite a while because I am doing house renovations and garage work. Whatever time is left is making cooling parts for people and working out the finer details of my dizzy relocation kit that I was to cheapy mass produce.

the 4age valves are quite long compared to the 4afe ones, why would you want to swap though? the cranks can be swapped but only if you have the same big end size