Isuzu G-series Twin Cam

Sorry I'm asking so many questions.

I was just wondering how much it generally costs to get the crank/bottom end balanced, and if it's worthwhile as far as power and reliability goes. Also, I'd generally be interested in how to squeeze a bit more power out of my engine (G180W) as it's in pieces, so now is the time to do the work.

Do the usual while the engine is getting rebuilt.....
Secondly go actually get some quotes off an actual workshop not a FORUM...

I think hes actually asking for advice as to what he can possibly get done to extract abit more power out of it.

Budget, what do you want out of it, what can you do yourself, budget? Theres a million things we can suggest, but being a tightass im going to assume you mean what sort of things you can do on the cheap.

- G200w Dizzy
- G200w Pistons
- Aftermarket ECU [you'd need this anyway]
- G200w F/I manifold and injectors
- Standard exhaust manifold

Get the standard manifold and remove the bit where it goes from 2 into a ~2.5" pipe [it unbolts]. Get an exhaust made up of 2 x 2.25" pipes, run them under the car and merge around the gearbox into 1 2.5" pipe. Standard cams reground slightly, and thats about all you can do without spending serious money.

Nick-

Thanks for the advice, as always, Nick . From the "being a tightass" comment I can tell you've picked up a few things about me... lol

I'm on the lookout for a G200W Dizzy (got a spare? lol). Would boring it out to 2lt make that much difference? Ok so that's a stupid question... I've heard bad things about boring out, but I guess that's what Isuzu did anyway. I'll call around to get some quotes, I wonder how much the pistons would set me back?

Is the inlet manifold the same between G180W and G200W? I know the plenum's different, I should keep my eye out for one of those.

How would you suggest the standard cams be reground? Different timing, or more lumpy? I've heard they're pretty lumpy as is...

Thanks for the help, I'll call around.

Good luck finding a dizzy,
Your best bet is to run a Camira dizzy I have 2 different styles sitting here,
The first has the internals of the Camira dizzy fitted to the standard with a different cap and rotor that no reputable parts store can stock nor that I can order in through work.
The second is a standard dizzy again but with the internals gutted and a dog tooth drive fitted and a camira dizzy modified to bolt straight onto the standard dizzy thus I can use all camira components.
I purchased this dizzy off gem some time back, Dont think he has any left for sale though.

Mate, im your age and a student as well so i know what its like to not have the cash to do stuff you want. The only real difference is im willing to wait to buy the good stuff, and save money doing the work myself. Anyway...

What do you want to do with this engine? Build it once and once only? Is it staying naturally aspirated, or are you going forced induction? Budget build or no-expenses-spared monster? There are heaps of little things or different setups you could go for depending on what you intend on spending.

Yes i do have a G200W dizzy and no your not getting it, i need it for mine . Shane, mind putting up some pictures of the two different dizzys, or how you went about modifying it to suit? Would make a good workshop resource article.

Plenum is different, and i think the runners are two. Pretty sure the G200 uses top feed injectors, someone correct me if im wrong. Cams would be reground to have more lift [apparently you cant get much more as the standard cams already have 400-odd, although im sure thicker buckets on the springs would theoretically acheive more lift] so youd be mostly aiming for duration and different power bands. Its an Isuzu motor. They like revs. Make the thing rev. You could get cam wheels made up, possibly even modify the old ones to dial the cam in but im not the person to speak about this.

Nick-

That's definitely food for thought. I've been thinking about it a lot lately, and I've decided that I should rebuild it now, making sure everything is in good condition, and then down the track if/when I have money saved up, pull the thing apart and go for some more performance. That way I won't be in a rush, I'll have a long time to call around and ask people, and I'll know something about the motor I'm working on first - I havn't started this thing once. As some may have heard, the reason I'm in such a mad rush is because my standard G161Z is f**ked and barely driveable on a hot day, or for long distances. I've gone over the thing a million times, something's wrong with it in a more serious manner than I'm prepared to go into fixing... Therefore I'm making it my priority to get the twincam running as soon as possible (within reason) so I can make the swap and have a reliable daily.

Someone was telling me computers don't need Crank Angle Sensors as the dizzy decides that stuff... It's a tad off-topic but what's a CAS look like? Is it universal or one part for one kind of engine?

As far as the G200W inlet goes, I could probably change that later as availability allows, which is sweet. I'm most concerned about stuff which involves ripping the whole engine out...

The DOHC does not use a Crank Angle Sensor.
Nor does the Delco system.
What exactly did you want to know about them, and no there not a universal part. For instance on a commodore (3. the CAS is mounted under the harmonic balancer, In most jap cars they are mounted in the dizzy.

Ah ok, I was told I'd need a CAS to run Delco. I'm glad to hear this. I'm pretty much just trying to sus out where I can find the parts needed to convert to Delco.

Water temp sensor - easy, autobarn or wreckers
MAP sensor - adapt from a sister Delco setup? Unless the twincams came out with them?
Manifold air temp sensor - adapt from sister Delco setup?
Ambient Barometric Pressure sensor - as above
02 sensor - already fitted

What else? I hear I need an electronic dizzy. Poida's been over the requirements but some ideas of sources would be great.
EDIT: Friend of mine said he had his EXA's crank, clutch pressure plate, flywheel, conrods and pistons harmonically balanced for $150. I'm stoked about that, I was imagining it to be about four times that much, I'll get it done I think.