G180W-A and G200W DOHC Motors

martin · backyard mechanic Joined: 04 Oct 2001 Posts: 900

Just a few points that may help when people are buying modding these motors, from what i have learnt myself after much research...

* G180W's originated as a pushrod motor waay back in the 60's and to this day have the casting for where the cam used to be
* G180w's came out in the 70's in the Isuzu 117 Coupe. Be cautious when buying these motors as they are muuuch older. They will put out good power but won't take as much compression and/or boost as the newer examples. You can discern between the older motors by the fact that on the rocker covers it will have 'isuzu' down one side and 'G180' down the other. The newer motors will most lilely have "isuzu' down one side and 'DOHC' down the other. Also the oil filter will be located on the side of the motor about midway up the block and the newer motors the oil filters are on the bottom left when looking at the front of the car. (you will have to remove the sump guard to change the filters.

* Older DOHC motors have the old isuzu logo which looks like a wreath with a symbol in the middle.

* The newer dohc motors will have an isuzu logo on the block.

* The newer isuzu twin cams came out in the following vehicles
- ZZ/R
- ZZ/T
- Piazza (late 80's or thereabouts) only released in japan but some can still be located here that have been imported.

* Telling the difference between the g180 and g200 - casting on the block same position as on sohc motors. Also, generally, G200 rocker covers are RED and g180 rocker covers are BLUE. There are some exceptions.

the earlier twin cams in the 117 coupes had black and dark green rocker covers. there are some others but i cant remember them..

i hope this helps someone out there!

Cheers
Martin

Slug · tinkerer Joined: 06 Oct 2001 Posts: 196

Not bad Martin, Most of that was on the money, that "wreath with a symbol in the middle" as you call it, is Isuzu writen in Japanese Smile

though you might want to know ... Michael

martin · backyard mechanic Joined: 04 Oct 2001 Posts: 900

ah okay no worries i think i was told that once but i forgot Smile

feel free to correct any of it!

Mooch · backyard mechanic Joined: 17 Oct 2001 Posts: 573

that same symbol is also on the steering rack, the conventional isuzu symbol is on one side and the "reeth" type on the other. Just a useless piece of trivia.

Stock TE · backyard mechanic Joined: 12 Mar 2002 Posts: 853

The G-series W motors actually started with a G160W (out of Bellett GT) which as you say was based on a pushrod motor ( which came out in the early Bellett GT's). Secondly the G180W came out in the 60's also in the Bellett GT. Last of the early W motors the G200W came out in the 117 coupe. Hope this helps

Stock TE · backyard mechanic Joined: 12 Mar 2002 Posts: 853

Sorry the G180W was the last of the early W motors which came out in the Bellett and 117. The later G180W and G200W came out in the Gemini ZZ's

CyBeR GeM · tinkerer Joined: 03 Aug 2002 Posts: 181

are the older g180's still go as fast as the newer ones

Stock TE · backyard mechanic Joined: 12 Mar 2002 Posts: 853

The 1.6 twin cam (actually G161W) (carby twin SU [I think]) had 120ps and (ECGI) 130 ps. The 1800 twin cam (carby Twin SU) had 125 ps and (ECGI) 140 ps and i've heard the later G180W (ECGI) only had 130 ps. Got the early model power figures out of guides and later model power figure off this site.

CyBeR GeM · tinkerer Joined: 03 Aug 2002 Posts: 181

so if your statistics are correct the older model 1800 goes harder? i just wanna know cos ive got the older one and i am hoping it still goes hard

Mooch · backyard mechanic Joined: 17 Oct 2001 Posts: 573

look, read the forum topic. this is not the place for questions. Its for facts! Post in one of the other forums if you must ask.

dont take it personally.

cheers
mooch

Stock TE · backyard mechanic Joined: 12 Mar 2002 Posts: 853

early ISUZU twin cams used to rev out to about 8 grand,the new ones only go to about 7,200rpm also the wreath symbol is a seal(like they used with wax in the olden days)

Trippo · rice boy Joined: 16 Aug 2002 Posts: 18

I got hold of a 1800 motor from a Jap importer a while back. It was a push rod motor (non cross flow), twin SU (hitachi? can't remember, same thing) set up. The block was actually a G180W block. Never had the thing going. A bit of trivia there.