project ae86 questions

[fxgt race]

the engine has been built and is a smallport that we have to turn into rwd,a few things that i need some info on as i an a fwd man,the water pump has been changed to a rwd pump and the pulley on the pump doesn't line up with the crank pulley,iv'e looked at the pictures and seen that original rwd 4age that a single v pully on it,is this what we have to run or is there something else that works.With the rwd pump on the alternater is in the way,did the original engine have the alternater mounted on the other side,is the anyone with a picture of an original engine that i could get hold off to have a look at or maybe have a look at someones car to get an idea of what we have to do,in auck if possible.a little about the car,smallport with 305deg cams runing link comp and slvtop throttles,the shell has been brought back to original condition and painted red,this car will be a absoulte mint example when we finsh it an will post it up in the projects with pitures as we build it.

[l1ttle_d3vil]

its not only the waterpump you have to change.
if you want rwd waterlines you have to use:

* rwd 3a/4a waterpump housing (has thermostat housing at the rear)
* rwd 4a waterpump pulley (has different offset to the fwd pulleys)
* rwd 4a alternator mounts (fwd alternator mount sits the alternator too high so it hits the thermostat housing when using rwd w/pump housing)

everything else can be fwd (crank pulley, alternator, waterpump itself)

[Zak]

its not only the waterpump you have to change.
if you want rwd waterlines you have to use:

* rwd 3a/4a waterpump housing (has thermostat housing at the rear)
* rwd 4a waterpump pulley (has different offset to the fwd pulleys)
* rwd 4a alternator mounts (fwd alternator mount sits the alternator too high so it hits the thermostat housing when using rwd w/pump housing)

everything else can be fwd (crank pulley, alternator, waterpump itself)

Mostly right, but you have to use the same pully AND water pump, so if he's putting the RWD in use the RWD pully, or vise versa. Also, if you use a FWD pump, don't use the fan or it's wreck your water pump bearing in no time.

It's cheaper to use the FWD stuff with the external thermostat than to buy all the RWD parts.

[fxgt race]

have the pump with thermostat housing on rear,and have another pulley that is a single v belt pulley or is the 4a pulley a 5v belt one

[l1ttle_d3vil]

Mostly right, but you have to use the same pully AND water pump, so if he's putting the RWD in use the RWD pully, or vise versa. Also, if you use a FWD pump, don't use the fan or it's wreck your water pump bearing in no time.

true, i got confused with keeping a fwd pump when changing to a rwd housing. AFAIK it was just the pulley which was different though...

if you wana chuck up a pic of the pulleys you've got i'll be able to tell if its a fwd or rwd one...they have entirely different offsets and its pretty easy to see.

edit - just remembered, im still using fwd waterpump AND waterpump pulley, with a rwd housing. only rwd stuff im using is the waterpump housing and alternator mount.

[Zak]

have the pump with thermostat housing on rear,and have another pulley that is a single v belt pulley or is the 4a pulley a 5v belt one

You need the 5 rib one.

l1ttle_d3vil, when we tried them, the distance from the pump face to the pully hub is different. So if you use the wrong pully the belt doesn't line up. ( never mind, you got it all right now )

[fxgt race]

we a using a rwd water pump,might just get a fwd one and change the front housing which is the right offset as the rwd one is 10mm longer.cheers for the help.

[Zak]

Oh, remember you need the right buy pass pipe as the 3a one is shorter, and the top head outlet is different. For those two reasons I would just use the whole FWD assembly with the external thermostat

[fxgt race]

I take the pipe you a talking about is the one on the rear off the thermostat housing that connects to the rear of the head,this outlet at the rear of the head has been changed to a thinner one to clear the firewall as well.was looking at the external thermostat set up but my mate had already changed the housings and pump so we will stick with this set up.

[Zak]

Na, the pipe comes straight off the top of the pump to the out let of the head going to the top of the radiator.

[fxgt race]

no worries that has been shortened and rewelded on an angle to clear the throttlebodies.I think she is good to go when we sort the front pulley out,have the pipe that joins the pump to the outlet as well

[jondee86]

I swapped all the original AE86 RWD parts on to a smallport, except
for the crank pulley (was going to use the stock smallport pulley). Found
that the A/C belt was 5-6 mm out of line. But from memory, the ALT and
W/P belt lined up not too bad.

Both crank pulleys are similar (2 x 5 groove polyvee) but on the AE86
one the outer pulley is a smaller diameter than the inner one, and the
pulley offsets are different. Using an AE86 RWD pulley solved the problem.

Cheers... jondee86