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

[Steve M]

It is a 22R item, aluminium.

http://www.xtremeclutch.com.au//file...ber%202010.pdf

[o_man_ra23]

That listing set looks very similar to the Fidanza listing set. You sure they make them on site and don't just import for non-domestic models??

[S. Lowlux]

I have 2 stock flywheels with no stress fractures. I would like to lighten one. Where do I put the cuts ? That protruding ring around the back looks like it can go, then I suppose its a matter of thinning the cantre & back.
Can anyone please give advise as to safe limits on thickness & weight reduction.
The other Owen. The different one.

[o_man_ra23]

Other Owen,

How much mumbo is your engine going to make, what kind of RPM are you going to run, and what kind of loading are you going to put on the vehicle??

You need to consider heat when you are working out where to lighten the flywheel, as the strength of the flywheel is partially governed by how well it can dissipate the heat of the clutch operation. Taking meat away from the back of the friction surface would be riddled with danger, though giving it a slight grooving might help, and enable you to remove meat from further out. The further away from the centre you remove the weight from, the better from a performance point of view.

But in all seriousness, for $530 with a new Excedy clutch, I just wouldn't bother risking a factory flyweel. If you don't want the clutch, it is about $440 for the flywheel on its own delivered.

[vpatrol]

Quick question, I know of an RG motor over here for sale which claims it has TRD camshafts and pistons in it. It's priced at a premium. What kind of difference do those make? Noticeable and worth the extra $$$?

[JustenGT8]

I have 2 stock flywheels with no stress fractures. I would like to lighten one. Where do I put the cuts ? That protruding ring around the back looks like it can go, then I suppose its a matter of thinning the cantre & back.
Can anyone please give advise as to safe limits on thickness & weight reduction.
The other Owen. The different one.

X-rayed or dye tested them? I bet they do

There is no safe limit. Just get an aftermarket one with the clutch kit as o'man says

[o_man_ra23]

Vpatrol - often people will claim the engine has 'TRD cams and pistons' thinking that the 18R-G had to be a TRD motor from factory.

A couple of questions for the seller - what profile are the cams, and how can they provide evidence that they are a TRD item. What compression and oversize are the pistons, how long and how many k's since install, and how can they provide evidence that they are a TRD item?

I would say personally, buy a stocko one that needs a rebuild for a cheap price, and bomb it.

[7t5-27]

Seems like the TRD cams I have have the part number stamped on the cam as well as the TRD letters, you might take the valve cover off and have a look, Good Luck, Be Safe
Greg

[vpatrol]

yeah, he doesn't seem to want to open it up to verify it. What difference did the cams and pistons make as far as performance? It would be nice to say I had TRD stuff inside it but only if it makes a noticeable difference.

[o_man_ra23]

Pistons won't make any difference if they are shagged.

www.paradiseracing.com was the cheapest place I came across to get forged Arais pistons, and to my mind a set os 92mm diameter high compression forgies would whoop worn out old TRD pistons any day. Also brings you close to 2.2Ltr. You will need to get a Cometic head gasket to suit the bigger pistons. Fleabay was the easiest and cheapest for this, as they were able to offer far better freight prices.

Kelford Cams over in the 8th state should be able to do you a set of hipo 18R-G cams to match the bigger pistons too.

Then look into a Fidanza aluminium flywheel to shed unwanted rotating mass to allow the engine to rev properly (Kameari and Jun also make lightweight CrMo flywheels, but they take 3-4 months to get if you are very lucky). Part number for the Fidanza is 130181 to suit 18R, or if you do what I did and tap out the flywheel bolt threads to 11x1.25 and use 22R ARP flywheel bolts, then the part number for a Fidanza flywheel is 130221. Fleabay was the cheapest.

[vpatrol]

What was different about the TRD compared to stock? New aftermarket is probably better but hoping to know the difference between them. Was it just higher compression and just a few extra hp resulting?

[o_man_ra23]

I would hazard a guess not huge amounts were different.

Please note that the engines used in racing were actually 16 valve, and were only loosely based on the 18R-G anyway, so anything TRD is just an aftermarket product which hasn't benefitted from the last 30 years of technological advancements in both camshaft and piston manufacture.

[river]

Hi,

Then look into a Fidanza aluminium flywheel to shed unwanted rotating mass to allow the engine to rev properly

A lightened fly wheel won't make the engine "rev properly". It will allow the engine to rev up (and down) faster due to the lighter rotating mass of the fly wheel.

As far as the TRD additions to the engine, I agree with Oman. Unless you can verify what they are and their configuration etc, then paying extra may not be worth it.

You can make some decent power out of a modified NA 18R-G, but there comes a point where the mods make the engine so angry that it would not be pleasant to drive on the streets and better suited for the track.

seeyuzz
river

[o_man_ra23]

Hi,

A lightened fly wheel won't make the engine "rev properly". It will allow the engine to rev up (and down) faster due to the lighter rotating mass of the fly wheel.

Running a potent RG with a lightened flywheel gave very quick response in revs and got to 8,500 rpm without effort, before the next event I changed the clutch and used a standard flywheel to save a few bucks and lost all response and took for ever to wind out to max just short of 8,000 and lost about 12 seconds around Eastern Creek.

Sorry River, could you please explain how losing 500RPM due to excessive flywheel weight is still classed as revving properly?? Allowing an engine to rev an extra 500rpm without any further changes is what I would class as allowing an engine to 'rev properly'. Perhaps you need to revise your definitions??

[river]

Hi,

LOL... the stock 18R-G red lines at 7500rpm, with the stock flywheel and it can go past that limit also - if your willing to keep it at WOT. Considering, in stock form, it's max power is at 6400rpm (max torque is at 5200rpm), then going past that is making more noise than power.

I determine the word "properly" as meaning without any problems. If an engine does not rev "properly" then I use that to assume it is erratic, lumpy, misfiring and a host of other problems that is stopping the engine from running efficiently and effectively, as per the manufacturers specifications. A stock flywheel does not stop the engine from reving properly.

A lightened fly wheel makes the engine gain revs faster, to its red line, compared to the heavier stock flywheel. Similary, the lightened fly wheel makes the engine lose revs more quickly than the stock flywheel. The red line is governed by the rotating mass of the engine (flywheel, crankshaft), cam timing, piston velocity, etc, and not limited or attributed soley to the mass of the flywheel.

So, both the stock flywheel and a lightened fly wheel allow the engine to rev properly. However a lightened flywheel allows the engine to rev to its limit quicker than a stock flywheel.

seeyuzz
river