18RG rebuilds and power outputs?

[M.J.H]

Ok thanks mate...

Is there anything else you RG guys would recommend doing to my motor before i put it together? Im going to be using it on the street and hopefully take it out on the track for a bit of fun eventually so i dont want it to be a pig to drive in town but i want to get the most out of this engine with out going turbo or efi...

So far iv got brand new pistons ( 9.5 comp i think.. Did toyota make 9.5 comp pistons for the RG? ), im getting the bottom end balanced, extractors, 45mm webers, 88250 head at the moment but i think the valves are stuffed , electric ignition, re-grind cams... I think thats all at the moment

Any thoughts would be great guys. Thanks...

maybe just a mild port on the intakes and match the manifold to suit.
Did this to the one I had with 45's and a mild port job made 120rwhp on the dyno.

[Damo82]

Gunna, its about 2.2L, the engine's running Holden 202 pistons, late model cam.

Owen I might consider taking a bit off the head to raise the compression as the 202 pistons don't have any dome.

[JustenGT8]

Engine 1 - 9.7:1 pistons, shaved head, ported manifold/head by yours truely, TRD valves, TRD regrind cams, 45mm webers...112rwkw at a measly 5000rpm, guestimate peak kw around 150rwkw @ 8000rpm

Engine 2 - turboed EFI, modded everything never dynoed but ran a wheelspinning 12.8@112mph in the RA23

[river]

Hi,

Engine 1 - 9.7:1 pistons, shaved head, ported manifold/head by yours truely, TRD valves, TRD regrind cams, 45mm webers...112rwkw at a measly 5000rpm, guestimate peak kw around 150rwkw @ 8000rpm

That's a very generous guestimate. 150rwkw is about 201rwhp... and when you take into approx 20% loss through the drivetrain, the engine is making 180kw (241 hp). The stock 18R-G, early model, pulled 140hp and I would of thought that you'd have to do a fair bit more than carbs, valves and porting to get another 100hp.... which is a 72% increase in power.

I'd expect that sort of power would require the engine to be also bored/stroked out to 2.4litres?

seeyuzz
river

[JustenGT8]

Just based that figure off the dyno curve River...at 5000rpm the cams had only just started to sing. This is back in 90-91 so chassis dynos were rare and the operator was old skool and wouldn't risk more than 5k :roll eyes:

So yeah just a guess and mayt be a little generous but you gotta admit 112rwkw at 5000rpm is pretty healthy when it pulled strong to 8000rpm.

[TA-022]

yeah id pay that ^^^^

plus we all know Justen's gots the goods!

[o_man_ra23]

Gunna, I would put in a new set of valve springs. You will probably need to take it to a head shop and get them to measure up what you will need. Get something that is good for about 9000rpm, and you will be safe. I got my last set through precision springs, and they were pretty nice, never had a valve bounce. Also, if your fairly sure your head will require more than a clean up, then maybe hunt down an 88270 head, as these had the best port design, and the largest valves.

Cheers, Owen

[Gunna]

Thanks guys ... I went and had a talk with the guy who is building my engine last night (im getting someone else to do it cause iv never built an engine and i dont want to stuff it up ). The valves look pretty screwed so were going to send it away and have it pulled apart and see whats going on... Do you guys think i should just try find a 88270 head? I saw that strat is selling a complete ported head in the classifieds but i think it mite already be sold ...

o man ra23, can you remember how much you paid for your valve springs? Id like to be able to rev to 9000 . I keep trying to give you rep but i have to spread it round a bit first it says but ull get some asap cause you have been a real help thanks...

Justen, sounds like you have built some pretty hardcore RGs nice work !

Oh and also if anyone knows where i could get some timing chain slippers that would be great cause the ones iv got are pretty stuffed...

Cheers...

[The Witzl]

the 88253 head is the same as the 88270.... but in reality any 18rg head in good condition will serve you well.

Valves are easy to get, and cheap too. I bought some recently from some place in Adelaide for $50 for 4 exhaust valves.

Thetoyman75 pm'ed me earlier... he's trying to get rid of a good 18rg head (just rebuilt)

[o_man_ra23]

The springs I bought cost $150. Price will depend on who you get them through. The springs themselves were good for 9000rpm, but the motor was only good to 7000ish, so I had some fudge factor/safety margin there.

Cheers, Owen

[Gunna]

Yeah i saw that in the classifieds just then... Iv just been talking to strat also though and he's selling a ported head with work done to it so think im going to get that so i dont have to get much done myself cause down here in tas there arnt many places that do that sort of thing ...

I know you have ended your RG sale but you dont happen to have any timing chain slippers you want to get rid of do you? Or if not is there anywhere i can get some? Mine are stuffed...

Cheers, Craig...

[Gunna]

The springs I bought cost $150. Price will depend on who you get them through. The springs themselves were good for 9000rpm, but the motor was only good to 7000ish, so I had some fudge factor/safety margin there.

Cheers, Owen

Yeah i thought that mite be the case... $150 not to bad though. Ill see what else is done to this head i mite be getting and then decide if im going to run better springs...

Thanks mate...

[Mr DOHC]

RR4 is the pn for my old springs, i used to run oversized stainless Ferrea valves to 7500rpm, no bounce, they are a precision brand

[Lambolica]

My old 18R-GEU - stock computer, bored to 2.2 (possibly stroked never found out) Some uber HKS cam, 22RE pistons. Turned 81rwkw. in poor tune.

[Sam_Q]

with standard computer? wouldnt that run lean in a setup like that?