up the power on the 18r

[MWP]

the 1st thing you can do which is essntially free is convert the carby to a mechanical driven secondary.
remove the vacuum pot link and somehow connect the shafts.
i used a piece of wire and its worked fine for now.
power gain was very impressive.

Yeah, i did that too back when i was running the original carb.
I found that the vac actuator for the second butterfly had perished so it never worked, so i wired it up so it opened after around 3/4 throttle. Made a big difference.

Only problem was that if you mashed the accel pedal at low revs, it could actually stall the engine because the sudden drop in vacuum in the carb stopped it from drawing through enough fuel.

I put up with that for a while and then bought a Weber 34ADM (off an old falcon) for $30.
Rebuilt it, changed the jets (soldered them up and redrilled), and all was good... much better than the old original carb could ever be.

I just got 9.17L/100KM off that carb on my current 21R too... and thats with some quite spirited city/hills driving. Quite good i think.

[timbosaurus]

The cylinder head and an 18R and an 18RC were radically different one was heart shaped and one was racecourse/oval.

Dragging up a REALLY old thread...

But I'm trying to identify a head, and not sure exactly what you mean by heart or oval shaped.

Is this an 18R or RC head?


Shot with E7600 at 2007-07-29

Cheers,
Timbo

[brett_celicacoupe]

from left;

oval, heart and the least common smiley face

[river]

Hi,

Hehehehe....

Getting back to an earlier question in this re-dredged thread... the 18R made about 111hp and the 18R-C made about 97hp... but I am going on memory here, which has been known to be fallible.

seeyuzz
river

[brett_celicacoupe]

i think you put one to many 1s there river


power specs here. its really splitting hairs though. an 18r OHC is still a slow engine no matter what variant

[timbosaurus]

haha... I want a smiley faced head

so can you tell what head that is Brett? From ur pic i'm guessing heart?

Cheers,
Timbo

[brett_celicacoupe]

no idea whats what really. i was only putting 2 and 2 together with that drawing

[timbosaurus]

damn... thanks anyways

[psi_guy]

Well...
How hard is it to convert an 18RC to an 18RG? what's involved? is it cheaper just to find a complete 18RG?

[clubagreenie]

yeeeeeeees

[river]

Hi,

Well...
How hard is it to convert an 18RC to an 18RG? what's involved? is it cheaper just to find a complete 18RG?

A CaG said... yes.

The only way you'll get all the parts required to convert an -C into a -G is to actuall buy a -G engine. So, you may as well use the -G engine rather than pull all the relevant bits and try to convert the -C engine.

Maybe if the block on the -G donor was stuffed then you could do it, but it requires a fair bit of work and it is less expensive and certainly less time consuming to just get a -G.

seeyuzz
river

[Spanner]

since the last time i posted on this thread i have made a few improvements, like a retro fit electronic dissy a set of 4-2-1 extractors a 2in system and a 32/36 Webber.
They have improved the power a little but its still lacking raw grunt, i know the 18r is no huge power house and the fact that I'm trying to push a tonne of steal (4wd) doesn't help either.
has any one ever attempted to retro fit EFI to the 18r would there be any benefit in doing this? is it possible or is it just a dream?

[river]

Hi,

EFI isn't going to get you more total power, but it may allow you to have more power over a wider range of rpm than what a carby can deliver.

You should look at dual webbers. There's manifolds for the 18R-C that are often being sold on eBay.

Also you might think about getting your cams reground.

Then you can go more ape and bore it out to a 2.2, and then stroke it to get it up to 2.4 litres. But, that's a lot of money to spend on a pig-iron engine, where you could probably get a better engine for the same cost or less.

seeyuzz
river

[thechuckster]

there was an EFI version of the 18R but i think it only appeared in USDM and JDM. Good luck finding a manifold - i only ever found a picture.

custom EFI on the 18R is a pain (speaks from experience here).

fwiw: these things can take a fair amount of advance when not lugging (e.g. not low rpm with foot flat) so you can dial in a fair amount of advance into the dizzi for cruise (this is obviously 10 037 times easier with programable ignition which you'd have to create from near-scratch).

[river]

Hi,

The 18R-E was the EFI version. It produced 130hp. It was an option engine on the RA25ST, and probably a few Toyota vehicles around that era.

And yeah... good luck finding one.

seeyuzz
river