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

[o_man_ra23]

clutch kit for 22R and 18R is the same part number from every aftermarket clutch manufacturer I have come across. Early 18R is the exception, but it is only the throwout bearing that is different due to the difference in clutch forks.

[Omegaman]

I made a general enqiury for regrinding a set of *****270 adjustable cams.

"Hi,
i'm looking to see if my 18rgeu cams (****270 adjustable cam sproket, single bolt) can be re-ground? If so can i get a price and details of requirement for this to occur. Can i choose 304/288 or must i go for your profiles, in which case 400A would be my preference.
please advise."

they cam back with
"Yes we can regrind the cams

Cost $297.00 for the pair
If you tell us the engine specs eg. Comp ratio head work porting etc and then we may recomend a cam suited to your needs.

On that note. thats is cheap for the pair for a start and two.
What were the profiles of the ******231 early, 3 bolt 18rg.
I also have a set of these ***231 on the car now, but i'm looking for more agressive cams with adjustable gears.
I read it somewhere but can find it now.
I want to regrind my adjust ******270's maybe to suit 3000-7000rpm power band.
Though i really don't know as a daily fun driver what to choose.
Any ideas or ways to determine this?

[Steve M]

A cam with something around 240 degrees @ 0.050" lift should still be good to drive everyday while adding some fun in the rev range that you want. Higher lift should be achievable as long as the lobes are welded and then ground. This cam should still have ok bottom end torque.
A cam with 250 degrees @ 0.050" is fun in the mid and top end but a bit annoying at low revs. These are crap when the engine is cold. (I got really good at left foot braking so that the engine wouldn't stall at lights on cold mornings).

Apparently Wade Cams are tending away from the weld-grind process due to reliability issues. We have one set of Wade cams here where the welding is starting to separate. They ruined a bucket

You'll need new shims whether you get a base circle regrind or a weld-grind, so that'll add $80 + postage.

I would recommend getting adjustable cams reground as the first set of regrinds we got were ground 8 degrees out of place on the exhaust cam. If they were fixed position sprocket cams, it would have been curtains for them.

Unfortunately there is less meat (lift) to grind on the later, adjustable cams.

I would also recommend drilling two more dowel holes in your cam gears to either side of the four existing holes. (makes 8 evenly spaced holes).

[Omegaman]

steve M, i'm looking at the spec's available here http://www.camtechcams.com.au/toy_4cyl_2tg3tg18rg.html

Will the 240's @.050 be similar to the rg *****231 cams, as these were the most aggressive from toyota?
The 240's have the rev range that i like. But the 250's should be still ok on an geu (efi) motor, even when cold.
Its a bit hard to get my head around this. As the lift on the 250 is not as high as the 240's
AS far as the gears, yes maybe extra holes will help. Though at least you can buy true adjustables from the USA.

[TRD184]

i gotta ask. where did you find a place doing regrinds that cheap as id be definetly interested

[joey]

subscribed.

[Omegaman]

i gotta ask. where did you find a place doing regrinds that cheap as id be definetly interested

see the link in my last post.

[Omegaman]

Also, it been suggested you can use rg cams on either the exhaust or the intack side.
Which brings me to this question. Can you mix rg cams with geu cams, maybe use the geu intack cam and the rg exhuast to reach a happy medium?

These are the gears i mentioned.

which i prefer these.

which are similar to what i have now on the *****270 cams.

[Steve M]

Omegaman,

The 88231 cams have approximately 215 degrees @ ~0.050" ( 0.047 measured value).
This would make those cams effectively 1 step two steps below the 240 degree cams, based on the differences between the camtech offered grinds.

The camtech 250 would likely have less lift (and even less still for the 260s) than the 240 to maintain a safe gap between the inlet and exhaust valves around TDC.
I have some 263 with 10.7mm lift and I can tell you that if they are a a small amount out the valves will hit each other (I don't remember whether that was with my oversize valves or standard ones).

When the duration gets more crazy, the lift must be sacrificed to save the valves.
The difference in lift between the 240 and 250 camtech cams in only 0.076mm. That's not enough to change my mind if I was buying them.

EFI will probably make the engine more friendly and smoother at low revs than poorly tuned 44mm carbs with 37mm large venturis (now using 34s, much better).

I would expect the top and midrange might not be too different between the EFI and carb set-ups but the bottom end would be different. Thase are my thoughts.

I thought about getting camtech regrinds perviously but now I am saving up for some new billet cams.

I am currently making some cam gears like the top photo. I have made the hubs and done the boring on the sprockets. I only have to do the drilling and the slot work now.

The gears in the bottom photo are to suit kameari / hks camshafts, which have more timing holes that the Toyota ones. They will still work with four-hole standard Toyota cams, though.

[Omegaman]

It would be interesting to see the end result of your gears project.

Also one of my questions was can each cam be exchangable?

Well my preference then will be the 250 cams, with a ported and port matched ****270 head.
Re seating the valve's and a good 3 way cut.
Thats now my aim.

edit. i meant 240d's not 250d

[Steve M]

As long as you're prepared to have a car that doesn't perform well in traffic but is great on hill roads then those cams should be fine.

I will be looking for something around the 240d mark as I've stroked the motor and am not looking to rev as high. I want bottom and mid-range torque more that top end power. Revs cause an engine to wear and die faster, hence my desire for a more usable engine at lower revs.

All of the standard Toyota cams that I've fitted have been exchangable without even having to change the shims. Their base circles are so close to identical that no shim adjustment ws required.

You should be able to use any combination of camshafts as long as attention is paid to setting the up properly so that the valves don't hit each other.

If using mix-n-matched cams you would have to do some timing tests to find your best result rather than being able to rely on the timing specs. (set up as per specs for each cam and then tune from there.

[Omegaman]

As long as you're prepared to have a car that doesn't perform well in traffic but is great on hill roads then those cams should be fine..

Sorry, i did mean 240d, as i said it previously.

i understand the implications of testing the exchanging of cams.
I'm not comfortable in even attempting it, just had to ask.

thanks

[7t5-27]

intake velocity has a lot to do with the performance, You can change this with the secondary venturis smaller is better for bottom none is great for mid and top. I don't know right off what the relationship between the cams that were discussed is to the 304/288 setup, but when my car had the 44mm carbs on them with that cam setup (now EFI) I had removed the 2ndary venturis and rejetted the car and drove around town with no major issues. At extended stop lights the car would start to load up but it was nothing an Italian tune up wouldn't fix. Once the car hit 3000 the engine would come alive throttle response was crisp and the car would pull to 8000+ if I would let it. HTH Be safe
Greg

[Steve M]

the car would start to load up but it was nothing an Italian tune up wouldn't fix. . HTH

Greg,

I am not quite sure what you mean here, I am unfamiliar with these term. Could you explain them, please?

I have heard of people removing the secondary venturis before. We tried larger ones (37mm) and found it a lot harder to rejet to an easily drivable standard. The bottom end performance was just not good enough.

Do you remember what jet combination you were using, what cams, (engine) and compression?

[7t5-27]

"Itialian tune up" Open the throttles quickly and quite fully a couple of times at rest to blow the carbon out and return to a somewhat smooth idle, The car was/is stock 2tg bottom with mild p/p and port matching on intake and exhaust, 9.8-1 toyota pistons, TRD valve springs, 304/288 cams, HKS steel flywheel, the jets I have written somewhere I will find when I return from work. Be Safe
Greg