g180w inlet valve size?

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Re: g180w inlet valve size?

Post by nut161 »

this has turned into quite the post!
Setup the cams and the inlet was two teeth retarded, not sure how it ran as well as it did although the power/torque did feel peaky and odd. Now its nice and smooth and really starts to wind up around 3500rpm, although i think i need to play with the timing and carbs some more before i can get my 48's on back in brissy.

Andys twincam is now the twincam in my coupe, traded out my big turbo sohc for his twincarb twincam. He threw the cam bearings in with the trade, so hopefully might reco a head over xmas and research different cam shim/buckets.

Is that gasket kit on ebay the only one available??


also i was just lookding over the net and nissan ca18's have a similar looking bucket to our twincams, without having one on hand atm is there any reason why a hydraulic lifter cant be used? they also come in solid replacements...

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Joined: 31 Jan 2006, 02:51
I live in: Vic
Location: Melbourne

Re: g180w inlet valve size?

Post by IZU069 »

I'm glad you had success with the chain timing. Interesting that it ran being 2 teeth out.

I wonder how it would be 1 tooth out - I recall some Gem G161Z racers saying the first thing they did was advance the cam one tooth (if I recall right).
However I am certain my Isuzu Guru would have mentioned something as simple as changing the valve/cam timing if it were to be an enhancement since that would be another freebie. I'll post-it note that to my cortex for the next time we speak (maybe in another 3 years...).
Of course changing cam timing does require care wrt valve & seat burn, and especially pistons hitting valves. And as some have found, they may not hit when rotated by hand, but hit when running. Same with cam profiles as those that have used the L2 profile have found (the L1 being the recommended profile for the ~230HP/170kW G200W street build).

AFAIK, that eBay gasket kit is the only full kit available. There may be something available overseas (USA??!) - try searching on bellett.net.
There are probably still Permaseal kits - both head-gasket only, and VRS lits (Valve Reco) that have all the top end gaskets & seals EXCEPT the front rubber timing cover to head seal (and maybe not the 4 half-moon shaft-end rubbers??).
But I don't like the Permaseal G200W head-gaskets - they are too narrow between the near-Siamese cylinders.

I'm only vaguely familiar with hydraulic lifters in UHCs (under-head cams - ie, pushrod engines) and they have shorter pushrods as a result. I can't imagine a hydraulic bucket being thin enough to substitute in a GW, and the there is the question as to how you would pump them up - ie, feed the oil to them.
And any solid equivalents I would expect likewise to be too thick.

Besides, changing the whole bucket means getting the correct outer diameter and from what I understand, no others exist.
I know a close match was from some Ford, maybe Lotus etc or local, and that's what had been used on that "expertly modified" G200W boat anchor I have - the one with the cotton-reel chain idler - but Guru reckoned that was a total waste. (It was guru that gave me that head because it was "totally useless!".)

IMO the solution for buckets is a supply of spare GWs - maybe we can exchange between users - especially when it comes to requiring a thinner bucket?
Otherwise it's a case of shimming up.
It's been another one of those one-day projects - I don't know which shims are (best) suited. I was lucky enough not to require different clearances in my 400Nm G200W (see how stable they are!).

Yeah - it's been quite a thread. That probably reflects the quietness of this site...
Given the right prompt allows certain people to spurt all they know, or the opportunity to update & clarify, or seek updates & clarification.
We need more prompts!
(FYI - a few such prompts recently appeared, however not wanting to stifle others from replying, I dealt with those via PMs & emails. That info has already been posted else should appear sometime...)
IZU069 - Isuzu means a lot to me.

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Joined: 26 Nov 2005, 12:48
I live in: Vic
Location: NSW-Victoria border

Re: g180w inlet valve size?

Post by Poida »

Hi Danny.

I found that same gasket set at MD Spares in Moorabbin but it's $50 cheaper. Postage would be about the same, but if they were mean enough to stack on the price to value add, I'm sure IZU069 may be able to pick it up for you on one of his southerly fly by trips if you had paid them for it before hand. Postage should be around $15-20 I would expect.

However, being that it's a G200W head gasket, it is going to have bigger bore rings. I have been trying to source a G180W gasket set and I just emailed PJ Gaskets in Japan asking if they make them and at what price. Let you all know what comes of it.

So you now have Andys engine... He sent me a set of those bearings too but I'm still yet to verify (hands on check) they are correct... we are hoping they are. Just be aware they may not be correct. It was a 'try them and see' buy and neither of us had found the need to pull cams out just to try and see, as you know, it isn't quite the same a a cam in a G180Z engine!!! You wouldn't do it if you didn't have to!

If we find they are correct, we at least know what to be looking for and once we know for certain, we can snatch up any we find.

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