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

[SlickRA40]

Hey im wondering if anyone has 18rg head studs for the cam caps
I only need one and have been told that id have to buy a whole set
Which i preferably would not like to do

[ra_28]

I'd try an exhaust shop? what are the thread size and length?

['ol_skool_'75]

Hey guys, anyone know where to find a RG oil pump?

[Pagie84a]

Picked up an efi manifold a little ways back with no ecu and half a wiring loom. Is a megasquirt gunna be the best option to make something of it have a pic of what I have here:
http://img842.imageshack.us/img842/6...un02165243.jpg

[timbosaurus]

Yes, MS is a great option for the ol RG.

I always wonder why people persist with factory ECU.

[Wil8115]

Pagie84a - yes the 88270 cams are the same. Well mine were.

will8115 - Even though the *****31's are single bolt, providing the set up with mix matching works, i dont see why you can't also mix single bolt and adjustable gears.
Normal running would suggest the cams to be straight up position or eg. advance cam one touth either way for more torque.

I want to do regrinds on my spare *****870 cams, but i wanted to know the *****31 cams grind details to make it worth while.
If the ****31's are 272 with 10.5 lift, then a worth while cam would be 289 - 295 max 10.5 lift, providing the engine is a little bit warm..
Cam tech have these details on their site.

i agree to a point.
mix and match (1) 3 bolt cam with (1) center bolt cam
As long as the timing cut out still fits the cam timing tool it should work. Or possibly be on the edge.
Anything to far outside of the timing cut out might risk touching valve to piston IMHO.
If you want something bigger then what they got let me know.

[Pagie84a]

Yes, MS is a great option for the ol RG.

I always wonder why people persist with factory ECU.

You wouldn't be able to recommend any particular squirty could you seems to be a few to choose from

['ol_skool_'75]

Found out through a mate new 18RG oil pumps will be available mid Julyish from Precision Engineering here in SA. I'll update once I know some more info

[ra_28]

Found out through a mate new 18RG oil pumps will be available mid Julyish from Precision Engineering here in SA. I'll update once I know some more info

Interesting are they custom making them or something they have found as an off the shelf item?

[timbosaurus]

You wouldn't be able to recommend any particular squirty could you seems to be a few to choose from

All depends on what engine hardware you wanna keep original, and what your willing to change.

Using the original points has worked fine for me in the past, but an worthwhile improvement is to upgrade to the 22r electonic trigger in the dizzy.

Use batch fire, as it keeps wiring simpler and won't make squat difference to power.

Run a single coil driver with the dizzy sending spark to the right cylinder, as it keeps it simple.

You can use the factory coolant temp sensor.

You need to change the TPS to one off a 22re. It bolts right up.

You need to install a IAT sensor. Buy a GM sensor and an alloy bung when u buy ur MS, and just weld it onto the throttle body.

If ur happy to DIY, then go for a MS2 v3.0 with msextra code. You could get away with a microsquirt if u want, then u have something a bit more professional and u don't need to solder it together, but it does mean u can't customise if u need/want. You don't need the extras of the ms3.

[Pagie84a]

Cheers timbo seems like a micro will be the go, have picked up a 22r dizzy etc already so Ill bung that all together with it

[andrewzuku]

Speaking of dizzies... I've been playing with mine to try and get the timing right.

It seems that somewhere in it's history, my 18R-GU has had the vacuum advance removed.

Based on how the mechanical advance cam and weights looks, I'm pretty sure it's an 18R-C distributor - with positions for both 15.5° and 17.5° of mechanical advance (31° and 35° at the crank). I'm currently using the 31° position.

• 18R-C Govenor Cam
• 18R-C Govenor Weights
• 18R-G Govenor Cam
• 18R-G Govenor Weights

A bit of Googling has me aiming for around 36° of total advance. This would mean that 5° of initial advance would be about right. However, that 5° is obviously meant to have vacuum advance added in low load situations like idle.

Without the vacuum advance, the car runs much better in lower RPMs with around 25° of initial advance. The problem there is that results in far too much total advance (around 56°) at higher RPMs.

Is there a distributor mechanical advance cam available with only 10° advance at the crank (so I can run 25° of initial advance)? Should I chase a vacuum advance mechanism instead?

Andrew

[Omegaman]

I'm about to embark on striping down and mix matching my 18rgeu, gu dizzies. i have 3 to take apart. also an 18g with points, so 4 dizzies.
my limited understanding is the Govenor weights range from 7-8 to 13's.
The higher the number the heavier the weight, which reduces the advance at higher RPM.
i have read also that changes by mixing weight and locating them on certain sides of the plate, can make a difference.

Eack of my vacuum advance mechanisms are different.
1 has advance and retard hoses, but no dial adjustment, the other has the same vacuum but a dial for adjustment.
Plus one other which has only advance but no dial adjustment. each having different Gov Weights.

Andrewzuku. Id be interested to see how you end up on this.
ATM my current dizzy cannot be adjusted to a 52-54 dwell. Idle sits at 1800 even at 5dec BTDC.
so i've come to the conclusion that the dizzy needs looking at being re-graphed maybe.

sorry i cant answer yr question.

[andrewzuku]

Thanks for the info.

I'm actually already running electronic ignition (Crane Cams XR700) instead of points.

On your weights, what is the 7-8 to 13 a measurement of? If it's grams, then that makes sense.

The 15.5° and 17.5° positions (remembering that one revolution of the distributor is two on the crank. So those numbers are doubled!) on my 18R-C mechanical advance cam are slots that a pin sits in. You can select either side by taking the cam out and rotating it by 180°.



I don't think the weights in my (18R-C) dizzy are changed when adjusting what RPM total advance is acheived. Instead, you would play with different strength springs. As far as I can find from Googling, I should have total advance at between 2500 and 3000 RPM.

From diagrams, it looks like the mechanical advance mechanism is the same between 4Ms and 18R-Gs. Diagrams seem to show 18R-C and 20R mechanisms are the same.

If this all ends up looking too hard, I may end up taking the car to a local classic car / carburettor guru (Motacarb in Nerang).



Your high idle sounds to me like either a vacuum leak somewhere, or the carby not directly connected to the throttle link/cable could possibly be out of balance, and not fully closing?

[Omegaman]

With my set up, i also have electronic ignition eg.(3x Elect Dizzies) + (1 with points).
Also its an geu EFI setup, not carbs. Just an FYI.
If you look under the weights, some have the numbers stamps. So must be in grams.
My reading suggested the weights are what defines the advance, the less weight the less rotation needed to throw out the weight, therefore advancing sooner.
vica versa, the heavy weights take more RPM to throw out and therefore advance. Rather than spring tension.

let me know if you want pics of each dizzy to compare the internals.
i was hoping to take them apart tonight or tomorrow to confirm some numbers and stuff.

i will check for vacuum leak also. cheers