4afe Modified -- Need More Advice!

[brianrdp]

Hi everybody... I've been reading the message boards and I think I could use the advice of some experienced Corolla Drivers.

I have a 91 AE92 4AFE 3 Speed Automatic, I've tried my best to make some modifications to bring it up to speed, but I would like some input to see in there is anything else I can do without changing the Engine or Transmission.

So far I've modified the following....

3" Cone Air Intake from TRD (to replace the stock airbox)
Ceramic Racing Headers (4-2-1) Much bigger than stock
Voided the Catalytic Converted
Added a Straight Through Carbon Fibre Muffler

The exhaust line is stock except for the Muffler attachment which is 2.5" from the last flange (after the resonator). I've reset Idle revving, redone the suspention / allignment and put some new Yokohama Tires.

I've seen the performance improve gradually with very upgrade. And is now much better than its origional state... in fact 0-60 used to be 12 seconds... now its just over 9 seconds. I know its still not much but its better than it used to be....

I'm looking for some additional advice on how I can continue to modify what I have and particularly the exhaust. Am I losing potential because there is no backpressure at all? (Except for the resonator that doesn't do much) What else can I do to this car without swapping engine or transmission?

Any and all advice on these matters would be greatly appreciated.

[brianrdp]

I heard you can help me out with this... i would like to talk to you about what else can be done etc... Post back to me of you can.

[Pineapple]

If you just empty out the cat, you're losing performance. Get a highflow cat. Get better performance and help other breath.
Make a custom CAI. SRI suck in too much hot air. Advance the timing 5deg. Use synthetic oil, flush it first. Do same thing with trnny if it wasn't done. If you want to spend $$$, get piggy back like SAFC and tune it on the dyno. Also Bosch +4 plug works pretty well in the 4A-FE.

[Flashmn]

heres what I'd do...
Throttlebody injection
some midrange cams with more duration but stock lift.
Race cat and full exhaust.

Bosch +4's suck. The only advantage the 4 electrodes have is that it has a longer change interval. The Denso/NGK copper ones are just fine. About advancing the timing, advance will make it easier to run it in low rpm, retarding it will give you better top end, but the Efi might go nuts with it.

[automatic]

I've got the same car, I used an adjustable fuel pressure regulator to tune the car after doing a few mods, runs excellent now,screams like a little V-tech we used to own..
I did some work to the head, just in the valve guide boss area, and the divider between the individual valves, on the intake side only.
A foam air filter, replacing the stock airbox was used with an air horn inside.My exhaust is basically stock, but opened up a bit around the tailpipe.
The fuel injection will re-tune itself using the oxygen sensor/ecu, but only in the lower revs; the wide open/hi-rev mixture is determined by the pre-set parameters(fuel pressure).
The timing has been bumped up to 15 degres at idle also,runs just fine.
I haven't checked what the max advance is on the fuel injected cars, but I know that the carbed cars have a lower initial advance setting, with more advance dealt by the ecu, giving the about the same max advance overall.

[REN69]

No matter what you do though.. that 3spd auto transmission will kill it all.. I would invest some money on a manual swap, or find a similar car with a manual transmission and sell yours.

[automatic]

Has anyone found a four-electrode plug(Japanese brand)for these motors?
They always made a difference in the Fiats, used Alfa plugs there, but when I looked, I couldn't find any for our cars, even a twin electrode plug.I don't really like Bosch platinum plugs either, never have.

[Flashmn]

Only thing the 4 electrode plugs do is increase the service interval, since when one electrode errodes it will use one of the other ones.

[automatic]

They're called a surface fire design, works better for airflow, flame propogation in the chamber, sorry you had a bad experience with the Bosch ones.

[JDAN]

How do i change the degree of the timing? can someone post insttructions, or at least some tips?