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turboing a 4A-GE 20v

Posted: April 16th, 2007, 2:17 pm
by 4a70
:twisted: i have a silver top 20v and thinking of adding some bost has any one done this? what parts are needed and how to go about doing this? :twisted:

Posted: April 17th, 2007, 10:23 pm
by Sully
I have a black top, and was considering this for a while. You're better off going 3SGTE.

Posted: April 23rd, 2007, 1:31 pm
by Chaddy P
Sully wrote:I have a black top, and was considering this for a while. You're better off going 3SGTE.


depends on whet u putting it in. 3sgte might be an expensive overkill.

in a levin a 4age 20v is fine on boost. u can purchase a set of 4agze rods and pistons and that will be fine for 350 - almost 400 whp. i dont think u need much more dan that on a fwd car. unless u drive on slicks all day.

this has been done before. 3sgte is heavier than an army tank is is not the easiest engine to work on (try changing one spark plug in 6 minutes :roll: )

Posted: April 23rd, 2007, 7:11 pm
by Aarong420
^^, can imagine changing the oil filter...
The silvertop came with GZE rods, but the pistons are 10.1 ratio, the GZE pistons are a lower compression than the ST, and although they dont have the cut outs for the 5 valves, theyll still work.
The blacktop are something like 11 or 11.5.1, and dont come with GZE rods. The rods are thinner and lighter making them easier to break. But the blacktop head is MUCH better for breathing, both intake & exhaust.
The solution, use a BT head, on ST block with GZE pistons, an yuh good to go.
Would definately reccomend atleast a piggy back to run this.

Try putting a BT head on a 7afe, add a turbo & management. = 7AGTE 1.8 20V turbo. now thats a project worth doing.

Posted: April 23rd, 2007, 7:51 pm
by 4a70
so by simply changing out the pistons in favour of the gze pistons in my silvertop im ok for compression? and what about lubrication? where can i get some of that for the turbo?

ps: i have this in a ke70 (RWD) :twisted:

Posted: April 23rd, 2007, 8:08 pm
by Chaddy P
Aarong420 wrote:^^, can imagine changing the oil filter...
The silvertop came with GZE rods, but the pistons are 10.1 ratio, the GZE pistons are a lower compression than the ST, and although they dont have the cut outs for the 5 valves, theyll still work.
The blacktop are something like 11 or 11.5.1, and dont come with GZE rods. The rods are thinner and lighter making them easier to break. But the blacktop head is MUCH better for breathing, both intake & exhaust.
The solution, use a BT head, on ST block with GZE pistons, an yuh good to go.
Would definately reccomend atleast a piggy back to run this.

Try putting a BT head on a 7afe, add a turbo & management. = 7AGTE 1.8 20V turbo. now thats a project worth doing.


7agte is a nice engine but u gonna have to buy rods for it. the stroke is long and the rods are weak. not my idea of fun when a rod fly from out of you block :shock:

Posted: April 23rd, 2007, 10:37 pm
by Aarong420
check one here
http://www.youtube.com/watch?v=WcpdbWCDtA8

K70, you got one huh....would love too see some pics man..
and yeah i believe they say the GZE rods are lower.

Posted: April 24th, 2007, 3:21 pm
by Chaddy P
Aarong420 wrote:check one here
http://www.youtube.com/watch?v=WcpdbWCDtA8

K70, you got one huh....would love too see some pics man..
and yeah i believe they say the GZE rods are lower.


gze rods, just wont work. there of a totally diferent stroke. however the pistons will work cause they are the same boar. but dont expect to retain the low CR that u would have in the 1600 bottom half

Posted: April 24th, 2007, 3:48 pm
by Aarong420
^^^, meant to say pistons.

The GZE rods and silvertop rods are the same. The pistons is what drops the compression.

So yeah 4A70, by swaping the pistons, it should lower the compression to almost the same as the GZE. I say almost because the C.Chamber will be different in the 20V.

Posted: April 25th, 2007, 12:24 pm
by smokey1275
is the gudgeon pin bore the same in these two rods?

Posted: April 25th, 2007, 2:36 pm
by Aarong420
good question, im not sure of this...but i was told by very reliable resources in Australia, that the GZE rods and Silvertop rods are the same rods. So im guessing that they might be the same bore. The length of the pin may be different thou, ill ask some people and see what they say..

Posted: April 25th, 2007, 3:01 pm
by TRD_FACTORY
The largest intake ports are from the first gen16v 4age(tvis). Hence the 4agze bottom end with a late model (non-tvis) head but with the tvis intake ports should be the best setup for a turbo. That individual trottles on the 20v make it an excellent N/A engine, but not to good for forced induction. How many stock manufactures have ever produced a forced induction system with individual trottles?

Posted: April 27th, 2007, 12:27 pm
by Aarong420
How many manifactures have made an eingine with ITB's in the first place, far less for ther 20V's..
The ITB's arnt my convern, cuz honstly...if theres pressure in the system, there not serving a world of difference, besides a better A/F mix.
But the head design of a 20V, is much nicer flowing the the big port.

Posted: April 29th, 2007, 10:57 am
by Aarong420
Oh thinking about it TRD, what about the SR20DET redtop that came in the pulsar, 4 throttle turbo, and thats a monster of an engine. It's got its advantages.

for the GZE pistns in ur car, heres a little more info.
They got 2 GZE models, the first gen came with 8:1 CR, and thesecond gen came with 8.9:1 ratio. Both cam be used to run turbo, but if you use the 8.9:1, then it will be an interference setup, meaning.that if the timing belt happend to burst, the pistons will more than likely hit the valves which is a big no no.
however if u use the 8:1 pistons, they will be non-interference, and you can run more boost.
So the choice is obvious....hey..anyone got these pistons to sell :D:D?

Posted: April 29th, 2007, 2:22 pm
by AllTrac
please dont underestimate the power of a boosted 4age 20V :twisted:

Posted: April 29th, 2007, 2:26 pm
by TRD_FACTORY
You may be able to run your 8.9Cr pistons but use the hKs 2mm head gasket which may make it non-interference.

Posted: April 29th, 2007, 6:51 pm
by Aarong420
I wish someone can post some pics of a 20V turbo project for us to see. What they did, what had to be done, how much $$ they spent etc...i guess no one wants to let out their secrets.

Posted: January 20th, 2010, 9:50 pm
by mr. mindz
there's a project im working on rite now..... a ke30... i'm looking for a T50 gearbox out of the AE86, to mate to a 4AGE 20v ST. interested in boosting this engine also.... anyone has any advice or know-how from past experiences of a similar project??? would definitely be interested...
There's the Greddy e-manage which i can afford to put on this, which one of the 2 is better in the Greddy?? or if theres one of a similar price but better for this project... ??? and advice on fabricating an airbox for the piping considering the 4 throttles.

Posted: January 21st, 2010, 12:12 am
by HaRdCoRe_YoUtH
mr. mindz, i have a boosted 20V completely forgerd internals, lots of engine upgrades..... Engine is a monster!

my experience is make sure u get correct compresion ratio, dont rich out and tune asap!

But i looking to sell of my car or engine anyone!

If you intrested in any think let me know!

Posted: January 21st, 2010, 4:59 am
by toyotajumbie
mr. mindz, if yuh looking for a T50 box, TRD Factory have one for sale.

Posted: January 21st, 2010, 8:41 am
by ruffrider27
well as we talking 20v bt how to changed a starter in that engine it way in the back of the engine

Posted: January 21st, 2010, 10:43 am
by eliteauto
ruffrider27, either remove the intake box and sway bar and tackle it from above, or jack the car up and work from below

Posted: January 21st, 2010, 1:42 pm
by ruffrider27
wich one more easy :lol:

Posted: January 22nd, 2010, 7:17 pm
by corolladude
i have gze rods... who want? :arrow:

Posted: January 23rd, 2010, 1:25 pm
by Hook
ruffrider27 wrote:wich one more easy :lol:


From on top is more little stuff to take out before u get to the starter, but IMO once u get the stuff out, it's much easier to get to the starter than trying to squeeze in your hand and a ratchet from below.
Besides, I doubt there's enough clearance on the sub-frame to get the starter out from there without loosening some bolts and floating it.
So from top is more stuff to remove, but below may be more labour intensive in terms of floating the sub-frame.

Just get your hands on a #5 allen key and a 10 socket with a 4" extension (or just a long reach 10 socket) and take out the air box/flutes. It's super easy on a ST cuz all the allen screws are on top, the BT screws face the firewall but it shouldn't be too difficult still, and if u don't want to put them back on afterwards, you don't have to, cuz it's a blacktop! :lol:
Just sit back and take in all the sounds of quad-throttle goodness :twisted:

Posted: January 23rd, 2010, 4:03 pm
by haydn28
mr. mindz wrote:there's a project im working on rite now..... a ke30... i'm looking for a T50 gearbox out of the AE86, to mate to a 4AGE 20v ST. interested in boosting this engine also.... anyone has any advice or know-how from past experiences of a similar project??? would definitely be interested...
There's the Greddy e-manage which i can afford to put on this, which one of the 2 is better in the Greddy?? or if theres one of a similar price but better for this project... ??? and advice on fabricating an airbox for the piping considering the 4 throttles.


mr. mindz which ever bottom end and head u decide to use , i can handle the engine management for u , the e manage blue is a simple good option to use.

my advice is to keep things simple and just turbo what u have . i can give u a proper tune , u can avoid detonation on pump gas and have a race/daily driven car.

i have a high compression 10:1 5efte stock rods and pistons, running 8 psi daily driven on super gas , no problems! :arrow:

Posted: January 23rd, 2010, 5:02 pm
by Hook
^^^ This was the point I was going to ask about. Wouldn't a high CR set up such as yours distribute the power more evenly through out the rpm band than if he were to lower the CR?
So unless it's going to be a track monster that only hits high revs, so lag isn't an issue, shouldn't a daily driven boosted 20V keep the existing CR?

There have been threads in other forums about boosted 20V engines getting all up in the 200hp neighbourhood on 0.8bar intercooled without touching internals, some even without management, just an adjustable FPR (I know sounds kinda hit-and-miss). So conch + fuel + high CR = a very fun car.

But with relation to a previous thread on the learning ECUs such as the 20V, would you suggest a stand-alone system instead?

Posted: January 23rd, 2010, 5:32 pm
by haydn28
Hook wrote:^^^ This was the point I was going to ask about. Wouldn't a high CR set up such as yours distribute the power more evenly through out the rpm band than if he were to lower the CR?
So unless it's going to be a track monster that only hits high revs, so lag isn't an issue, shouldn't a daily driven boosted 20V keep the existing CR?

There have been threads in other forums about boosted 20V engines getting all up in the 200hp neighbourhood on 0.8bar intercooled without touching internals, some even without management, just an adjustable FPR (I know sounds kinda hit-and-miss). So conch + fuel + high CR = a very fun car.

But with relation to a previous thread on the learning ECUs such as the 20V, would you suggest a stand-alone system instead?



the fact that the car will be daily driven , its better to have it high compression , advantages include : better throttle response , less lag , better fuel economy, ability to use a large turbo.

downside : harder to avoid detonation on low octane gas , it does not mean that boost will be limited , its just that proper tuning with high octane fuels will be required if u were to run say 20 psi, 7-10 psi can be run very safely on super gas with a good tune ( tuning high compression engines requires more skill and good hearing)

the learning ecu is not a problem , depending on who is the tuner, and of course stand alone is better if u can afford it

id think 250whp is more than possible on stock internals and stock compression :arrow:

Posted: January 23rd, 2010, 5:42 pm
by Hook
:cool:

Posted: January 23rd, 2010, 7:40 pm
by Advil
HaRdCoRe_YoUtH wrote:mr. mindz, i have a boosted 20V completely forgerd internals, lots of engine upgrades..... Engine is a monster!

my experience is make sure u get correct compresion ratio, dont rich out and tune asap!

But i looking to sell of my car or engine anyone!

If you intrested in any think let me know!


how much u asking for for the engine and stuff?