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

[timbosaurus]

Good tip Mate!

I've heard this happening to at least two other RG's

One might have been TwentyEights, but I can't remember.

Something for everyone to check though

Timbo

[Norbie]

Yeah I had the same thing happen on my 2T-G years ago, it didn't make any strange noises but it certainly did run like a bucket of crap until I pulled the carbies off and saw what was going on!

Another thing to watch out for is the stock 18R-C engine fan which makes an annoying high-pitched whistle at high RPM. I had this happening on my 18R-G for years and could never figure it out until I removed the engine fan in favour of an electric fan - then the noise disappeared. Strange but true!

[The Witzl]

Yep - loose venturis is common on the ol' twincams.... seen it happen to a few people now!


The only odd noise my 18rg makes now is that it sounds like it hits a vicious cam profile at 5000rpm.... it literally roars, and its kinda scary.

[Norbie]

The only odd noise my 18rg makes now is that it sounds like it hits a vicious cam profile at 5000rpm.... it literally roars, and its kinda scary.

Heheh mine does the same, I was really surprised when I first drove it after the Haltech was installed and tuned. I'm not sure if it was the deletion of the airflow meter or the actual tune which made the difference, but it certainly sounded very different above 5000 compared to the old factory setup!

[The Witzl]

Heheh mine does the same, I was really surprised when I first drove it after the Haltech was installed and tuned. I'm not sure if it was the deletion of the airflow meter or the actual tune which made the difference, but it certainly sounded very different above 5000 compared to the old factory setup!

Yeah i think it's the removal of the AFM that's made the difference too.
I used to kinda be able to hear it with the AFM, as i had a crappy pod filter bolted straight onto the AFM.... now without the AFM and the same pod filter, the induction roar is really really pronounced above 5000rpm.

Actually, if i rev it that hard, my idle screw vibrates undone and my idle goes up to 1500rpm

[Ren_RG28]

Man, if only I knew about this a year ago!

I'm glad to know it's a common problem, at least I know the symptoms of a loose venturi.. I took it for a spin last night and it's almost a completely different car! I'm also beggining to wonder if the new dizzy cap made a difference too. Just pulls a whole lot stronger and doesn't want to stop revving! Before in 3rd it used to hit around 110 and feel like it had enough, but now it goes all the way to 140 and loves it.

Very happy

[timbosaurus]

Karl, I know you have listed a few different power figures for your different RG combos, but i'm curious to know what you think a particular combo would make. Its strange, cause I usually think newbs who ask "how much power would my VTEC make if I put on stage one cams, stage 7 BOV and painted my rocker cover red?" are knobs

anyways...

With the supposed "perfect stock combo" of 210 cams, 253/270 heads, 9.7 bottom end (or a little higher from shaved head), a decent exhaust and EFI intake, and with a decent tune in an aftermarket programmable fuel and ignition system, would you expect to see >90RWKW's?

I've seen a few rebuilt, stockish, carbied, dizzied RG's (i'm assuming they were the 9.7 engine) in the 80rwkw region, so I would have thought that better ign/fuel tune, along with the better flowing head would push them over 90rwkw. That's not too far from the magical 100RWKW mark. Have you seen any simplish RG's (not talking super hi-comp, big dollar or turbo engines) make the 100rwkw mark?

Cheers,
Timbo

[The Witzl]

i'd think 90rwkW is about the best you'll see out of a stock parts engine, even with the best combination of different stock parts.

My "almost best" combo of 9.7:1 pistons, 88253 head and a fresh rebuild only made 80rwkW (with poo tuning)... but to make another 20kW would be a bit much i think.

To get beyond that, you would really need cams IMO.

[timbosaurus]

I know aftermarket ignition and injection would not give a *great* gain in peak power, more for general drivability down low, but I certainly would expect some gains. 10kw might be a bit optimsitic though

Even though the 210 cams are considered the most aggresive, are they still quite tame in the scheme of things?

Options seem to be the aftermarket billets like wade/crow/tighe.. do many people go with these? hard to find secondhand?

I probably wouldn't bother with regrinds... out of curiosity though, do they grind a new profile onto the lobe then use super fat shims to add lift, or weld on material to the cams then grind a new, lumpier profile?

Cheers,
Timbo

[river]

Hi,

The 210 cams are still quite tame, even though they are slightly more agressive than later 18R-G cams. The engines were set up for normal road use and reliability and that is why the cams are more tame. Like all engines for road cars, the designers have to take into account the lowest common denominator - that is, the average dickhead driver - and therefore the engines are more tame.

You can always grind the cam for something a bit more lumpy or get yourself custom cams. However, the more agressive the cam the less happy the engine will be at lower revs around the streets.

seeyuzz
river

[timbosaurus]

Leso, yes, judging by the second segment of the part number you gave, they are the original camshafts.

Here's what I've found so far. Add in anything that I've missed.

88210 head 88210 cams three bolt
88
88250 head 88231 cams three bolt (may have been retrofitted, may not have been)
88250 head 8850 cams single bolt adj.
88253 head 88251 cams single bolt adj.
88270 head 88270 cams single bolt adj.

I pulled apart an 18RG which I bought of the forums here with the intent to re-ring and re-bearing. Turns out it was built from an 18R-C block, so one would only assume it has the low comp bottom end.

When I rebuild it I will just use the best parts I have lying around from a few engines to make a stock daily runner... nothing special.

I'm getting to the "put back together" stage soon.

The cheapest parts I can find are at www.gimmecarparts.com.au, but I haven't checked offline shops like repco etc yet.

ACL rod bearing set - $50 (should be same as 18R)
ACL Full gasket set - $240
ACL Main bearing set - $90 (should be same as 18R)
ACL Piston rings - $60 (should be same as 18R)
Solex carby kits - $89 (Ebay)

Has anyone seen better prices? If so, where?

Also, the cams in the engine are stamped with *-88270. It's possible these aren't original, but the rest of the top end seems to match. Anyone seen the 88250 head, 88270 cams combo before?

Cheers,
Timbo

[barned01]

careful with the piston rings.
i got a set of piston rings once and they weren't right for the pistons.
From what i have been able to summise, you need a different set of piston rings if you have 18rgeu pistons in there.
the 18rg(ur) pistons do however use the same piston rings as an 18rc

main bearings i paid about 70 for but that was 2 years ago

[leso]

Timbo,
I have just purchased most of the parts your'e thinking of buying..

complete gasket kit retail 280 with discount 221
piston rings retail 68 with discount 56
conrod bearings retail 56 with discount 44

So the prices you got arent two bad..as i get a 21% discount from my local auto1 store.. also got the bottom tensioner, upper inlet side guide (that needs to be bent).

As for the power outputs...dont know if mine will ever see a dyno...but i have the 9.7 pistons...a 253 head (at the shop atm getting some small welding done..gonna talk about some porting on monday) also have some wade regrinds 298 duration . Will run the twin 40 mm webers for a while..but i think i may need some 45's to get the best out of it..also have some good extractors and a 21/2 exhaust, will also sort out some kind electronic ignition before i finish the rebuild...

oh and btw...gunna paint the block red..good for another 5kw

cheers Leso

ps ...with regard to the exhaust side upper chain guide...i have found a guy in brissy that will rebond mine...going to meet him 2morra, he said that he has done heaps mainly for jaguars ..mine will probably have to be done by hand..

[timbosaurus]

I'm just bummed I missed out on jeffro's new 9.7 pistons. I have a set of 2nd hand job up in brissie, but I'm guessing they will be the 8.*:1 puppies.

It seems to be a shame to replace all the consumables and put it all back together without using the high comp bottom end

Thanks for the info guys, Guess I'll just have to deal with it costing $500 just in consumable parts Bit different to the ol' 18R

[ra_28]

ps ...with regard to the exhaust side upper chain guide...i have found a guy in brissy that will rebond mine...going to meet him 2morra, he said that he has done heaps mainly for jaguars ..mine will probably have to be done by hand..

Will like to see some pictures of the finished item fairly interested in getting some of my spare ones rebonded.

Cheers
Alex