gearbox for twin cam

ca18_datto · newbie Joined: 19 Jan 2002 Posts: 1

gday all,
I need to know whether a standard gemini 5spd gearbox will bolt up to a twin cam (1.8l or 2l) n/a Isuzu motor. If it doesn't could you reccommend one that would. Thanks!
- Charlotte

Shark · tinkerer Joined: 03 Dec 2001 Posts: 226

Sorry Charlotte, this isn't really a response to your question.

Can anyone tell me -
Does the G180W have an all alloy block?
Would a G180W bolt up to a gemini 3 speed auto?

Thanks

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

i cant tell you exactly, but on my ZZ/T with a g180w, looks pretty similar to my old gems gearbox. It sits in the same place but i can't really get a good look at where it joins cause theres to much airconditioning shit in the way. My short answer would be yes cause it uses the same remote shifter etc, i just think that the mountings for the box may be a little different cause on the g180w the starter motor is on the opposite side of the engine so it maaay be different. Not sure sorry!

gem · tinkerer Joined: 23 Dec 2001 Posts: 152

NO a standard gemini 5 speed will not bolt up to a twin cam engine.The starter motor is on the other side.What you can do is fit the main part of a std 5 speed to a twin cam box front housing.But you need a twin cam box to start with.I have seen a rough job done once where the bell housing was cut around the twin cam starter motor and this allowed a std box to be used.Good luck.

gem · tinkerer Joined: 23 Dec 2001 Posts: 152

The g180w is not an alloy block.Do you mean the 1.8 twin cam ???? if so why bother with an auto.
To bolt a three speed auto to this engine you would possibly need the backing plate from the back of the motor from an auto, if it is different to a manual.There should be no other real problems.

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

do you happen to know the oil capacity for the twin cam?

Slug · tinkerer Joined: 06 Oct 2001 Posts: 196

No the gearbox from a single cam will not bolt up to a twin cam , starter motor is on the wrong side Smile

... Michael

gem · tinkerer Joined: 23 Dec 2001 Posts: 152

It depends on the type of sump.Most twin cams use the std Gemini sumps so go for the gemini fill amount? how much ???
My sump is modified with an oil cooler, it takes 8ltrs of oil.

Shark · tinkerer Joined: 03 Dec 2001 Posts: 226

Gem, by G180W I meant the later model Twin Cam motor. When you said that "the g180w is not an alloy block", were you refering to the older model SOHC G180? Or is the Twin Cam G180W block made of cast iron?
The reason that I would want to use an auto, is because I don't want to change the gearbox on the gemini that i would be putting the G180W in. I have also heard that the auto box is tougher than the manual.

Dave · tinkerer Joined: 04 Oct 2001 Posts: 322

Autos are really only good for fanging in a straight line ie drag races etc.

If you wanna have FUN in a Gemini, you'd need a manual.

By the way, the SOHC 1800 is the G180Z, so the G180W is going to be DOHC.

By the way, I beleive that a Bellett 4-speed will bolt straight up to a G180W DOHC - there was a Bellett going around Adelaide with one, and it wasn't the earlier DOHC engine from the two door - it was a Gemini DOHC engine.

I'd warn that the Bellett box probably isn't that strong though. I pulled some burnouts in mine and it held on OK though.