4AGE 20V silvertop compresion-power-gearbox

[CEL_1JZ]

Gday just a few q's ive had my 20v powered ae90 onthe road for bout a month now an just dont seam to have much balls, maybe im just used to turbo power from when i had my 1j...

im not sure when the prev owner did the conversion he changed the gear box for he 20v of left the 6afc gearbox in place, if so how can i identify what gearbox is in the car? could this be a reson im felling a lack of power as it fells like my mates excel which is sad

i notice it has a far mount of torque when going up hills so not sure if it has torque gearbox instead of somryihng that lets the engine rev freely enough if that evn makes sence..

i did a compression test on it last weekend and came up with

1st 150 psi
2nd 140 psi
3rd 132 psi
4th 125 psi

performed a wet test an all came upto 150psi, are these readings correct or is my engine in desperate need of a re build?

i have replaced oil nulan 20w50, dist cap and rotor button, fuel filter air filter, spark plugs and running it ot BP Ultimate.

any ideas would be great an also a dyno workshop close to brisbane that any1 can recomend so i can get a power run?

Thanks..

[KARNAGE]

the 20 valve would fall quite short in the guts department compared to the 1j. the gear box wont change anything in power deliver or torque but the gearing will alter acceleration. is the gear box fine with the engine ie, not crunching or anything as i have heard that the gear boxes from a 4afe wont last long behind a 20valve but not to sure bout a 6afc.

[CEL_1JZ]

the 20 valve would fall quite short in the guts department compared to the 1j. the gear box wont change anything in power deliver or torque but the gearing will alter acceleration. is the gear box fine with the engine ie, not crunching or anything as i have heard that the gear boxes from a 4afe wont last long behind a 20valve but not to sure bout a 6afc.

it was crunching a bit but i guess that was due to the master cyn bout to give way as it did on me last night, replaced it with new 1 this morning an now all gears are smoth as. an yeh accelaration is slow from what i expected form a 120kw engine.

[KARNAGE]

thats the power it puts on in the brochures from toyota, i had a blacktop with a link computer exhuast and better intake and only pulled 109kw before that it was stock and only pulled 89kw at the wheel a stock silvertop would pull slightly less again so what you are feeling is most probably a normal amount of power that a 20valve puts out.

[CEL_1JZ]

thats the power it puts on in the brochures from toyota, i had a blacktop with a link computer exhuast and better intake and only pulled 109kw before that it was stock and only pulled 89kw at the wheel a stock silvertop would pull slightly less again so what you are feeling is most probably a normal amount of power that a 20valve puts out.

whats the comp worth, who should i speak to an where did you get the car dyno? im living in bris now an have no idea were to go.. it has sports ex bout 2.25 but still running standard air box i wanna fix that with aftermarket pod inthe next week :-)

[KARNAGE]

i still have the computer actually as i sold the car without it, it cost me bout 2500 to buy fitted and tuned it was a good power jump but was quite expensive at the time. In brisbane im not totally sure i got mine done it townsville. i had a 2 inch mandrel bent system with a high flow cat trd extractors and a good lukey mufler kept the noise down but gave a very nice note when hittle the throttle. if you are fitting a pod make sure you do it properly, as in make a inclosed box for it because if you dont the heat soak in the engine bay will actually loose power compared to the stock intake system.
Even if you can get a k&n filter to fit the standard box would be the best thing for it.

[CEL_1JZ]

i still have the computer actually as i sold the car without it, it cost me bout 2500 to buy fitted and tuned it was a good power jump but was quite expensive at the time. In brisbane im not totally sure i got mine done it townsville. i had a 2 inch mandrel bent system with a high flow cat trd extractors and a good lukey mufler kept the noise down but gave a very nice note when hittle the throttle. if you are fitting a pod make sure you do it properly, as in make a inclosed box for it because if you dont the heat soak in the engine bay will actually loose power compared to the stock intake system.
Even if you can get a k&n filter to fit the standard box would be the best thing for it.

im planning on getting a custom 3mm alloy box fabricated with lid and duct cold air from front bar of body kit, going to get new ex as its not mendral bent. guess person who dont it didnt wanna lash out a few xtra $ to do i right

[pornstr20v]

get a 6speed lsd gearbox c160 will feel like you just got 50hp nos hit you

[adamaw11]

1st 150 psi
2nd 140 psi
3rd 132 psi
4th 125 psi

IIRC, those figures would be pretty low, I thought they were meant to all be above 155? or 160?

I had a silvertop that was burning some oil from worn rings, the comp test showed in the low 150s allround I think.

Does it blow much smoke under load?

Is the vvt working? unplug the solenoid and see if it feels/sounds any different.
and if you're running 98 octane, try advancing the timing more.

based on those figures though, sounds like you'll wanna either rebuild it, or change it for a blacktop.

I wouldn't bother with any dyno runs if the compression test was that bad.

[Hiro]

6AFC gearbox would be a C50. Generally a C52 or C56 is the minimum recommended for a 20v (what silvertops came out with from factory), a C160 is a good idea too but not essential.

[KARNAGE]

plus arent the c160's really hard to get your hands on? as when i was purchasing my 20valve black top front cut i was looking around for ages trying to get one with it but had to settle for the 5 speed.

[CEL_1JZ]

IIRC, those figures would be pretty low, I thought they were meant to all be above 155? or 160?

I had a silvertop that was burning some oil from worn rings, the comp test showed in the low 150s allround I think.

Does it blow much smoke under load?

Is the vvt working? unplug the solenoid and see if it feels/sounds any different.
and if you're running 98 octane, try advancing the timing more.

based on those figures though, sounds like you'll wanna either rebuild it, or change it for a blacktop.

I wouldn't bother with any dyno runs if the compression test was that bad.

hey it did blow a bit of smoke under load just wasnt sure if it was running correct air fuel mixers, thats why i thort of getting it on a dyno

[KARNAGE]

how is the oil consumption does if it chews through the oil best bet is you have worn out piston rings. you said you were running stock computer so i doubt your mixtures are going to out.

[CILAchainsaw]

Bro, my 20V was p!ssing out smoke (from worn valve guides though) and still reading 180 - 190 (though I do supect it has hi-comp pistons in it). They say that if your comp readings are more than 20psi different from each other anyway that it's time for a rebuild, as they all should be within 20psi of each other (mine was within 10). Get your spanners out son

[CILAchainsaw]

Crap, I just realised this was 3 years old, I really should check the dates first. My bad...
So how did you go with it anyways?