For the love of a tractor engine: The life and times of the 18R-G

[Steve M]

The domes on the high comp pistons do extend up past the deck by upto about 7mm (9.7:1 pistons) but the valve cutouts are only present where the valve collision is most likely (ie. one circular cut at 32^ to vertical on the inlet side and one on the exhaust side). These cuts extend downward along the path of the valve past their interseption with the piston crown to a depth of upto 2.5mm below the block's deck.

So what you see looks like a flat top piston with a chamfered, levelled lump in the middle of its top it and someone has taken some core samples on a 32^ from vertical angle from two sides that are deeper that the level of the original flat top piston.





I have no practical experience with flat topped pistons in 18RG's so I can't really comment on their performance.

[Steve M]

I hope that explanation helped, but I was really just looking for an excuse to look at my 22R/18R hybrid pistons again.

[crowncustom]

I hope that explanation helped, but I was really just looking for an excuse to look at my 22R/18R hybrid pistons again.

Yep I forgot that the relief did sit slightly below DUH.
When ya have rebuilt so many different motors over the years you get a bit hazy
Would be interesting just to see if any other people out there have put flat tops in there RG and what their comments are on performance.
Cheers Brett.

[Norbie]

Dont sell off the turbo 18RG stuff norbie!!!
... unless you have something else to use?

I'm selling my OLD turbo setup which I bought off Justen Simpson 10 years ago and never got around to using. Don't worry I'm keeping my new turbo setup, ie HKS manifold and TD06 turbo.

[The Witzl]

oh - i forgot all about that one now didn't I.... bastard.

[Steve M]

Here's a site that may interest people trying to chase down 18RG 92mm bore pistons.

http://www.escort-us.com/piston/toyota_c.html

Yes, they're only cast, but with the current exchange rates being what they are, they're only $630AUS.

[o_man_ra23]

Had a look at 22R pistons from the ACL catalogue on Tuesday, it looks like the earlier Celica etc items are domed?? I would be expecting flat tops, then again the diagrams were a bit ambiguous. The later Hilux, bundera etc 22R pistons had an 8CC dish in them. Looks like I will need a set of the celica etc pistons (if I can confirm they are not domed... wont work with my closed chamber head).

Cheers, Owen

[timbosaurus]

You talking about slugs for an RC now Owen?

[RAd28]

i know this goes against about 2million different state and territory, and especially TOYMODS laws, but i believe this link may be of benefit to someone with an 18R-GE....

[o_man_ra23]

Only helps if you can speak Japanese Gerrard. Timbo, yes I am talking about slugs for an 18R-C... the engine closely related to the 18R-G. I need to do some pipetting of the combustion chambers in my spare head and find out what my compression ratio would be with the 8cc dish pistons.

Oh, and I should find out this weekend if I have 16R con rods... as I will be doing my engine swap then.

Cheers, Owen

[sillycar chick]

Ahh but sensei Gerrard can speak Japanese! Where do you think he's been getting all his RA25 and TA27 goodies from?

Manual would be a great collectors item, especially in Aust

[o_man_ra23]

righto, well if he can speak Jappo, then it would be pretty RAd to have one

Cheers, Owen

[roadkill]

Hi All

One thing that i think hasn't been brought up is ignition for the 18RG - ie plugs and coil. Any suggestions on something better than standard/18rc stuff.

bEn

[The Witzl]

plugs - NGK BPR6EY
Coil - whatever suits your system (points or electronic)

Personally i run a bosch MEC717 coil, but i have aftermarket ignition control.

[airfireman1]

I am about to finaly put an 18rgeu in the 28, just a couple of questions.
What different oxy sensors are available due to the fact that the one fitted to the original exhaust manifold is huge. I have a brand new set of extractors and I am sure that there must be a better oxy sensor that I can fit, ie: weld a new threaded nut to take the sensor and nut rather than have to use the huge mounting setup as fitted to the old cast manifold.?
Is it worth upgrading the steel fuel line, (feed) to a larger size? keeping in mind that it will be kept pretty much stock.
One more question , what are the thoughts on the VL external EFI pumps? and will they lift fuel or just push fuel?
Cheers