4age specialists only, no n00bs please

[Roof87]

Sup,
I have a 4age 20valve (silvertop) and just purchased a microtech LT8s which is already flashed to suit the 4age. Now i am thinking of purchasing adjustable cam gears and setting that at around 270 degrees.
Based on this information i have 2 questions.

one, is what other naturally aspirated mods can i do that is worth while with a computer i.e- porting? flywheel etc...

two, does anyone know a trusty, knowlegable mechanic in the sydney, who can do the installation and tuning of the comp, cams etc...

Cheers guys.

[IN 05 NT]

starting off, a good set of tuned length extractors will open up flow,

port matching....(when they match the manifold and the head intake ports increases flow)...good idea as well as polishing,

assuming that your running ITB a good set of ramtubes, increse the air flow pickup,

most important thing with NA is having smooth flow, less turbulence,

fly wheel willincrease response,

theres plenty of shops that will work with a 4AG....they have been around a while and most performance shops have quite a knowledge of them,

blake

[beerhead]

You're going to have endless troubles with a Quad throttle body motor on a microtech, there isn't enough adjustablilty in the TPS % tuning mode or in Vaccum mode. Not saying that you won't get it to work, it just won't run very clean or efficiently. I had alot of troubles with an LTX-8 on a bigport with big cam's. The vaccum range allowed for only 4 x 16 of the 16 x 16 map to be used, and with quad's the map signal will probably be as bad.

The other trouble you'll have is the ECU doesn't have enough aux outputs to run the idle control valve, so you'll have to get around that too. I've decided to retain the standard ECU on my silvertop till I can afford an adaptronic or autronic, which are regarded as the best ecu's to run a 20V from tuners that I know.

Your other mod's there are down the right line, a nice port job and a lightened flywheel will really let the 20V sing.

[Roof87]

thats completley arguable....with the right dyno specialist and tuning, the vaccum range can be ammended im not sure about the TPS mode though. Manual aux outputs can also be insterted my friend.

thanks.

[oldcorollas]

Now i am thinking of purchasing adjustable cam gears and setting that at around 270 degrees.
one, is what other naturally aspirated mods can i do that is worth while with a computer i.e- porting? flywheel etc...
two, does anyone know a trusty, knowlegable mechanic in the sydney, who can do the installation and tuning of the comp, cams etc...
Cheers guys.

hi Guys,
surely you would want to set the cam gears at around 110ish? 270 is a bit of a wide angle

as with all NA mods, it is a balance of good and bad.
the stock ex-manifold is good until a certain point. the quads should also be ok. you can make it more of a fartmobile with bigger exhaust and open trumpets but a specialist like you will know that already.
flywheel also has tradeoffs. depends on the cams you have.
as for people to install or tune, perhaps look at the club sponsors for a start, or look through the forum to see who has been recommended

as for putputs, the MT has the PWM needed for the IAC? as for vac range, you might only have a range of about 25-30kpa, especially if you go to larger cams. you might want to double check you can change the load range to 60-100kpa absolute.. or even triple check.
have fun.

[beerhead]

I didn't realise extra auxillaries could be added, that's pretty handy. Keep us posted on how the tune goes, and what the dyno doctor does to get the vacuum range to increase, this would be helpful info for all who go down the ITB path.

I've heard that running the tubes closer to the TB's and having a canister to merge the vaccum works better than 4-2-1 for the vaccum tubes, but haven't put it to the test yet.

[oldcorollas]

properly sized canister and properly sized/placed restrictors work well to get a stable (enough) signal.

[Celica RA45]

why does every 1 have problems with running quads ,mine are not even balanced with vacuum ,they are all seperate from each other it idles fine at 800 rpm and all im using is tps and the map sensor is set for atmosphere ,and im running big big cams

[ira11y]

Its easy on some computers to just drop off the MAP sensor at idle and use the TPS vs timing to set mixtures and achieve a nice stable idle speed, wolf can definately do this, not sure about microtech's ability to do the same

[takai]

Aye, i back up Glen on this one, no problems here running big cams and quads. Idles at 1200rpm only because we cant get clearance behind the idle screw to turn it down further.

NA mods to a 4AG is a PITA, and definately a case of severely diminishing returns. Especially with the stock bottom end. Im about at the limit of that with 130rwhp.

Stu is right with cam timings too, 270* is massive overlap and it will die in the botty.

[oldcorollas]

why does every 1 have problems with running quads ,mine are not even balanced with vacuum ,they are all seperate from each other it idles fine at 800 rpm and all im using is tps and the map sensor is set for atmosphere ,and im running big big cams

with big cams, you should be able to get a better idle using quads than with a plenum... and using TPS, you don't have to worry about sensing vacuum... so yours is ideal setup

silvertops etc don't have very aggressive cams, but should still be dead easy to do... if factory can do it.. a half decent aftermarket should do it..
heck even megasquirt1 had no problem running alfa with quads with idle kpa of about 75..only using MAP.... all these fancy schmancy ECU's should have no trouble

[takai]

Oh yeah, with the cam gears on a stock 20v you will lose VVTi if you install the exhaust one.

[beerhead]

In TPS mode you can tune anything to work well, it's gonna run like a big electronic carby But if the car is a streeter, and off throttle efficiency is needed the microtech will never cut it.

I spent an hour on the phone talking to a swag of dyno-tuners around brissy the other day because I was offered an LTX-8 real cheap. Most of them said they could get a half decent tune, but basically said I should save some $$$ and get a better suited ecu. In TPS mode you'll find the Microtech won't have as many load points as you'd want.

[Ben Wilson]

I'm sure there are worthwhile gains to be made from decent poting and port matching on a silvertop. The factory port match between the manifold and head (at least on mine) is shocking and the inlet ports look like they could benefit from a failr bit of cleaning up.

The exhuast valves are the same size as the inlets, there may well be advantages to be gained by getting bigger valves in there as well.

[finney]

which car is the 20v going into? If its a FWD AE92/82 then i'd say keep the factory extractors and look at getting new secondaires back. The factory 20v secondaries seem to be fairly restrictive over the crossmember and i'm sure that by taking advantage of the space there and getting a larger diameter exhaust (2 1/4") over the crossmember should see some good results.