20v Head On 4a-gze

[Mr Revhead[RL]]

if you use a 7a then u get the stroke, which is what makes torque, i doubt you can bore a 4a block enough to get 1800cc....

 

also if you keep the revs sane you wont need to change the rods.

and fit 4agze pistons.

 

just don't go buying heaps of bits you don't need, remeber the 4age and 4age rods and cranks are the same, just theres 2 types of rods, the later ones are thiner, but still strong enough for 9000rpm and 250-300 hp.

[1G-GTE KE70]

so you suggest working a 7a?

 

no matter what engine i would most likely get custom forged internals for strength so i can rev it higher safely.

 

so the 4a and 7a have identical bore but the stroke is just longer?

[1G-GTE KE70]

I have found an interesting page on this

 

http://www.billzilla.org/starleteng.htm

 

go down to the title that says 7AGTE 20 Valve. thats pretty much what I want only I'll get forged internals as he states the 7A rods aren't so strong.

 

[Super Jamie]

although I do not favour the 20v head for naturally aspirated engines

haha pwnd :S

[Mr Revhead[RL]]

yeah longer stroke can't rev as high, but its all relative, 8k wont be a prob with forged internals.

 

so if you want a torque monster 7afe is the way to go.

what id do is draw up plans for 2-3 diff combos, and price up parts, see what you think then

[ancullen]

if you use a 7a then u get the stroke, which is what makes torque, i doubt you can bore a 4a block enough to get 1800cc....

 

also if you keep the revs sane you wont need to change the rods.

and fit 4agze pistons.

 

just don't go buying heaps of bits you don't need, remeber the 4age and 4age rods and cranks are the same, just theres 2 types of rods, the later ones are thiner, but still strong enough for 9000rpm and 250-300 hp.

I once heard of some people creating an 8AGE (yes, EIGHT-A-G-E). It had a capacity of something like 2000cc. Of course, a lot of this was custom I think.]

 

Just checked while writing this post. Yes, there was an 8AGE, created by someone in the USA who has now retired. I found his address on this site > http://www.solidlight.it/toyota/tech_engine.htm under some info about 7AGE's and 8AGE's. This page also gives brief details on how to build a 7AGE.

 

My engine (when I get the cash), is going to be built for circuit racing. It's a late model 4AGZE (8.9:1 compression). I'm thinking about 20-valve head, standard supercharger running standard boost, maybe a bit higher compression forged pistons, 304 intake cam, 288 exhaust cam, and maybe bigger throttles. I'm aiming for 300hp at the engine or about 220hp at the wheels.

[Super Jamie]

the TRS 8A-GE kit (custom crank, rods and pistons for 7A only) is no longer in production, as Topi no longer works for TRS or even makes car parts. club4ag thread here

 

aaron willis, who i give webhosting to, has a 7A-GE in his AE11 MR2, see here for buildup

http://te51levin.superjamie.net/

Edited April 18, 2005 by Super Jamie

[1G-GTE KE70]

cool. i'll check those links out when i get time.

 

thanks guys. looks like the 20v 7A-GTE is the way to go.

[beerhead]

Hey,

I thought you might wanna read a bit about stroking a 3SGTE to 2.2. Seems not to be too hard, use a cyro-forged 5S-FE crank, a ST165 flywheel and clutch (same pattern as crank) and some custom forgies with some cyro'd rods. It'll be alot cheaper mating the 3SGTE to a W5* supra box than a 4A 5A 7A I believe aswell.

@10 PSI = 260 BHP

@15PSI = 323 BHP

 

 

http://www.koracing.net/stroker.html

 

enjoy :D

Edited April 20, 2005 by beerhead

[1G-GTE KE70]

thanks for that info.

 

 

either way i'd most likely have to get new manifolds etc so it would fit in rwd as both the 3S and 7A are FWD. and also a 7A is far cheaper than a 3S especially considering i'm going to be redoing internals etc anyway.

 

 

thanks again

[beerhead]

sweet as, a nice capacity 4 turbo should be a bucket of joy :D

 

Can't wait to see how your beast turns out :doublebird:

[1G-GTE KE70]

I have spoken to the dude who does stroker kits for 4a's etc and he said the 20v head wouldn't really be worth it due to valve problems/tuning etc

 

so a GZE head on a 7A-FE block or something. haha

[Mr Revhead[RL]]

what valve problems?? tunning? how does the numebr of valves affect that?

 

theres plenty of 7ages here with 20v heads, in fact i don't know of ANY with a 16v head....

[1G-GTE KE70]

and I quote...

 

"If you are wanting to turbo I would suggest a 4agze 16 valve head as the 20

valve wont offer any real advantages, plus its easier to put really big

injectors and a large plenum on a 16 valve head. Tuning a turbo with

multiple throttle bodies isnt straightforward. The 20 valve needs HD valve

springs if you run high boost due to valve float and the head doesnt handle

the higher thermal loads as well as a 16 valve.

 

If you put GZE pistons with a 20 valve you will need to have valve reliefs

to suit the 5 valves cut into your pistons."

[Super Jamie]

as the 20 valve wont offer any real advantages

i know alot of people who would beg to differ with this statement. some of them engine builders who have put together alot more powerful motors than you or i will ever see