4a-fc Owners

[GJM85]

I spent a lot of time reading through the threads available for the AE92 4A-FC 1587cc twin cam 16 valve first phase motor.

I've owned mine for 5 years and driven it from 205000 to 360000kms. I've spent many hours keeping it on the road and trying more innovative things to improve the standard intake and exaust systems. After spending last night and this morning scourging the 16 pages of the "General Mechanical" forum i've come up with the best near standard cost effective way of keeping an old motor on its toes. I spent 3 hours this morning rectifing and readjusting the old girl.

I will attempt to convey some important information for noobs attempting to race their standard 4A-FC motors when the money just ain't coming.

 

*to be continued...

Edited April 26, 2010 by mirage1172

[GJM85]

I'll start with a few parts and tools you will need to carry out your 3 hour overhaul. Also any extras you may have already or have the money to buy.

 

Tools and Equipment

• timing light
  gasket glue
  dremel grinder
  wet and dry sand paper
  philips head screw drivers
  needle nose pliers
  spanners
  sockets
  rags
  

Parts

• gasket paper
  flange ring gaskets
  exuast manifold gasket
  manifold studs and nuts to suit
  new air filter
  fuel filter
  oil filter
  engine oil (grade depending on wear of motor)
  coolant
  

Extras

• alloy wheels
  low profile tyres
  extractors
  2 inch exaust
  muffler or cannon
  sports steering wheel
  high energy coil
  heavy duty leads and plugs
  

...will edit too add anything I have missed as i go.

Edited April 26, 2010 by mirage1172

[GJM85]

This is my first real thread so i'll do this slowly. Feel free to add input or correct me if needed.

 

1)Clear a Patheverything with a orange dot

-remove the air intake pipes and air filter box.

-remove the bash plates under the car

-remove the heat shield

-remove the exaust manifold from the head and the flange

-drain oil

Edited April 26, 2010 by mirage1172

[GJM85]

2)Exaust Manifold & Flange

The aim of this is smooth flow.

-The manifold can be difficult to separate from the flange so you may have the replace the studs. The nuts will have loc-tite because they vibrate loose.

-Once spearated use the dremmel to clean the rough edges of the 2 pipes protruding from the flange. They are rough cut in manufacturing.

-Use the new exaust manifold gasket as a template, dremmel the ports on the manifold out to suit. Get into the manifold as far as possible because the inside casting is extremely rough. You want to smooth it out as much as possible. If you can afford it, extractors would be a more suitable alterantive.

-You can then use the manifold gasket as a template on the head and dremmel out the exaust ports on the head to suit. You don't need to go too far. The intake ports and valves are not too big so you don't want to expand the exaust ports to far. I left mine about 3mm diametre smaller than the gasket to avoid decreasing back pressure. Cleaning the carbon deposites in the ports helps a lot.

-Use the wet and dry sand paper to polish up and blow out the ports and manifold really really well. You don't want alloy filings falling into the valve seats or cylinders.

-While the manifold is off its easy to change your oil filter.

-Reassemble the manifold and flange. You'll need your gasket rings, loc-tite on the studs and reattach to the head with your new manifold gasket.

 

easy stage 1 port shine and manifold match :wink:

Edited February 24, 2013 by GJM85

[GJM85]

3)Exaust System

As for the rest of the exaust i kept it standard from the manifold to the resonator and added the 2 inch pipe from there to the tip.

I chose the Zetti 4inch cannon because it has a much better sound and doesn't sound tinny at the top end like some cheaper cannons you can get. I used to have a Lukey perfomance muffler which worked well but again sounded like a bee in the top rpm range. The cannon cost me $270 and the $130 to have it fitted with the 2 inch pipe.

If you can get extractors or have a bigger budget by all means go out and spend the big $$$ on a stainless high flow cat, extractors and 2 1/2 inch pipe, but I think your wasting your money. We are dealing with a eco 90bhp motor here and that was 20 years ago.

 

first image - exaust attachment (green dot- resonator, blue dot- standard pipe, red dot- 2inch pipe attached where the standard 1 1/4 inch pipe started)

second image - Zetti 4inch cannon

third image - standard cat

forth image - my old lukey muffler

Edited April 29, 2010 by mirage1172

[GJM85]

4)Cooling Systemonly if it's broke

From here i'll go into the cooling system. It started when I cracked a radiator due to over heating. I believe there is a blow in the head gasket because I was getting oil into the cooling system. Overtime this has glued up the thermostat causing limited flow of the coolant and increased running temperature. pop

 

-To start I went to the wreckers and picked up a second hand Denso radiator from an EFI model.

-New top and bottom radiator hoses for $9 each

-I removed the old radiator and thermo fan and while I was there started removing the AC which didn't work anyhow.

-Cut the AC belt, removed the motor and pully. I made my way around removing the pipes to the fire wall, removing the AC radiator and AC fan.

-Dropped in the near new radiator but not the hoses yet

-Remove the thermostat housing, chuck the thermostat. not needed in these Australian conditions though some people gut and refit the thermostat to regulate coolant flow

-Cut a new gasket, use the gasket glue both sides and refit the thermostat housing

-Fit hoses and refill radiator

-Important! Leave the heat sheild that covers the manifold in place as it prevents excess heating of the radiator which is situated quite close to the radiator.

 

Now this is where things became interesting and it took me a few months and this website to figure out the extent.

*Because I was missing the thermstat, the flow of coolant is faster, the removal of the AC components also allows more airflow through the radiator. The end result is the running temperature of the motor is substantually lower. This running temperature will directly effect the standard air induction system of the engine.

 

NB: The thermofan sensor is situated in the AC piping near the firewall and once removed your fan will run while the ignition is turned to 'ON'. It doesn't matter because your usually driving when your 'ON'

Edited April 26, 2010 by mirage1172

[GJM85]

5)Induction/Inflow

 

This gets a little bit complicated. Using aftermarket components for the induction when your using the standard carbi seems a waste of time.

 

-To start I removed the front attachment that draws air from behind the head light and from the front wheel arch. (image 1)

-Fit a new aircleaner. These can be expensive. $25-$35. But you'll notice the difference.

-Now in the second image you will see a number of coloured markings.

• The orange dot represents the hot air induction fitting.
  This contains a vacuum powered vent that opens during warm up to draw hot vapour from the exaust manifold (shown by blue dots & red arrows).
  It has several benefits. It assists in warming the engine faster reducing cold start wear and also assists in vapourizing fuel whilst the choke is open.
  The white arrows show where the vacuum line feeds the shut-off vent. (shown in image 2 & 3)
  

-Here's the relation to the cooling system. Because the engine is now running cooler and never gets to its original running temp this vent stays open feeding your engine with hot air from the exaust manifold full time. Remove the vacuum line and block it off at the air cleaner. (image 3) NB: I left the black exaust vapour pipe in place becuase it looks ratty without it and also more likely to avoid a defect notice should the Po Po even look under your hood.

-I also removed the standard grill and folded an aluminium one from grill I bought at Supercheap for $25, allowing increased cool air over the radiator and into the induction.(image4)

Edited April 26, 2010 by mirage1172

[GJM85]

6)Ignition if you have some extra coin

 

-I removed the standard coil and fitted a Bosch high energy coil. $40 image 1

-Champion premium coil wire silicon leads. $110 image 2

-NGK heavy duty plugs. $30 (Not Irridium. Waste of your money on this engine)

-New distributor cap. $26

-New rotor. $10

 

A premium ignition system is a good investment because there is nothing more annoying than your cheap leads arching out on the plug cylinder walls. You'll think you've done a head gasket!Bosch leads are cheap

Edited April 27, 2010 by mirage1172

[GJM85]

6)Finish the Service

 

All in all a service on this engine entails the following-

 

-Check powersteering fluid.

-Check brake and clutch fluid.

-Check front and rear brake pads

-Check battery level & remove any corrosion

-Radiator coolant level

-Wiper washer water

-Air filter.

-Fuel filter.

-Oil filter.

-Oil change.

 

NB: The recommended oil grade for this motor is 20W50.

The oil you use should be dependant on the amount of kilometers and the wear on your engine. Mine has 360,000km on the OD but its more likely around 390,000km as I had a different cluster in for sometime. I currently use Gulf Western Engine Extender 25W60 SG/CD. It's pretty cheap and great for my old donk.

Edited April 26, 2010 by mirage1172

[GJM85]

8)Timing & Tuning

 

-Starting with the carbi, make sure all vacuum lines are intact and in good condition. Even one leak will cause misfiring or sluggishness.

-Leave air/fuel mixture as standard

-Leave the idle at 900rpm at warm idle. Don't try and set the idle on a cold engine.

-Don't be afraid to give it a venturi full of carbi cleaner.

-Check there is no slack on the accelerator cable as it will stop the carbi reaching 'full open'.

 

The most important factor in a well running 4A-FC, the timing.

 

-Warm the engine

-Release two 10mm bolts on the distributor

-Using your timing light, turn the distributor until the white timing mark on the crankshaft pully lines up to the 15 degree mark on the timing gauge. (image below.)

-Quickly tighten the 10mm bolts.

-Recheck the timing.

-You may need to reset your idle now your timing is slightly advanced.

-Idle should be smooth and quiet. 900rpm.

Edited April 26, 2010 by mirage1172

[GJM85]

9)Suspension and Wheels

 

-Finally, an effective way of achieving a higher rate of acceleration is through the use of stiffer suspension and low profile tyres on suitable size wheels. The AE92 Corolla Seca CS came standard with 13X6inch steel rims and 185/75 series tyres.

-I changed to a 15X6 1/2inch alloy rims with a 195/50 series tyre.(image 1) I could of gone 16 or 17inch in the wheel department but was more concerned with real on road performance rather than the big bling look. This wheel and tyre combo has roughly the same diameter as the standard set up but is far lighter.

 

-The bitumen roads in south Brisbane are among the worst in Australia so I opted for a degree of ground clearance, only using a 2inch lowering spring.(image 2) It was a little bit bouncey until the springs set in, but now it's really quite stiff. It still has some bodyroll but is very stable in heavy cornering. Could probably fix the body roll with a strut brace.

-Again could have gone lower but speed bumps and gutters aren't friendly towards my exaust. People tend to go for the cheaper option of cutting standard springs down a coil or two but it makes for a seriously rough ride and will destroy the struts in no time.

 

-Also in the steering department I went for a small fat leather wheel with a 1974 Corolla boss kit. Helps when throwing through tight corners.(image 3)

Edited April 27, 2010 by mirage1172

[GJM85]

I would welcome and further input from anyone with know how on how to improve the 4A-FC motor or and corrections in my current posts.

Edited May 10, 2010 by mirage1172

[GJM85]

10) Strut Brace

 

-This model, the CS Seca, did not come with a front strut brace. I found one on ebay for $50. :yes:

-I gave it a light sand and couple of coats of engine enamel.

-I did the cam cover while I was at it after removing the stickers with a blade. purely cosmetic, but totally super race!

-The holes required for the standard strutbrace were marked but not drilled. It's under the SR Super Response sticker on the firewall

-Removed the vent grill.

-Drilled them out with a 10mm bit.

-Jacked the car up on the centre crossmember. Enough to get the front wheels off the ground.

-Bolted to the top strut towers and then bolted to the firewall.

-The firewall bolts were too long so i had to nut them from outside to prevent interference with the wiper arms

 

Bob's your uncle...

 

Fully sick handling improvement... totally rigid, hardly any chassis flexing. for Mr No it all!

Edited May 10, 2010 by mirage1172

[Hiro Protagonist]

Fully sick handling improvement... totally rigid, hardly any body role.

 

Strut braces don't stop body roll, they reduce chassis flexing. Sway bars/anti-roll bars stop body roll (or reduce it).

[GJM85]

bye bye AE92 it was fun loving you and ever better playing with your bits.

 

Hello KE20, let's see what your insides look like......