G63B after market/performance intake manifold?

[elsupremo]

Does anyone know of an intake manifold other than the stock one?

I would like to eliminate the coolant circulation and lower induction air temps.

[geezer101]

AFAIK there isn't one - excluding a downdraft twin carb intake from a GSR based engine or maybe a single or twin DCOE sidedraft. I have messed with the G63B intake manifold and you can improve coolant flow through it, along with almost completely deleting the EGR attached to it. When you look into the thermostat housing there is a 'dam' where the coolant from the base of the plenum chamber passes up into. This channel is really restricted and somewhere about halfway the gallery that feeds into the thermostat housing there is a hole barely big enough to poke a pencil through. This does 2 things that aren't good - the obvious restriction of coolant and something that is just as nasty. If you get fragments of iron oxide from the block that make it through the engine to the plenum base in the manifold, they can potentially get trapped here. This will eventually rot out the bottom of the manifold which was a common problem with these engines, and prevent the already strangled coolant flow further. I do not advocate the following fix but seeming I had to get a new bottom cover welded into the coolant chamber as a result of this issue, I took the biggest new HSS drill bit that would fit into that channel and drilled through the restriction point. I took it easy while going through there as I was well aware that going at this with guns blazing was going to end badly. This mod should have increased coolant flow by 100%.
I've got pics of it on site... somewhere

[dash]

sounds like the goal was to eliminate coolant flow(added heat) thru the intake altogether. I'm thinkin jus weld the sucker shut

I've bought a mitsu 2.0 staz motor or two that had that circular plate under the untake welded up


Set a performance goal, listing parts needed for the 2.0 to accomplish it
Maybe can hack off the runners short and run inexpensive bike carbs. Dunno how serious the build tho

[geezer101]

sounds like the goal was to eliminate coolant flow(added heat) thru the intake altogether. I'm thinkin jus weld the sucker shut

I've bought a mitsu 2.0 staz motor or two that had that circular plate under the untake welded up


Set a performance goal, listing parts needed for the 2.0 to accomplish it
Maybe can hack off the runners short and run inexpensive bike carbs. Dunno how serious the build tho

I wouldn't weld it shut. This could affect coolant flow from the rear of the head to the front and create a hot spot which is not good considering how sensitive the G63B is to excessive heat. Bike carbs - yes. Would completely transform the performance of the 2.0 but I wouldn't use the G63B carb manifold. Instead I would use the lower half of a 4G64 intake manifold, lop off the runners and weld alloy tubes onto it. I have been thinking CBR900RR carbs are the ticket. Big throttle butterflies and venturis and the basic layout of the carb rack is a compromise that is close enough to mate up to the paired port cylinder head.

[dash]

dual sidedraft setups don't have any coolant flowing thru the intake, do they ?

[geezer101]

dual sidedraft setups don't have any coolant flowing thru the intake, do they ?

If they were ever made as an aftermarket item for the Sirius G63B, more than likely no. I know they were made for the Saturn 4G32/4G33, and the Astron 4G52/4G54.

[noahwins]

Dual DCOE sidedrafts manifolds for G63B were made by Tomoe Shokai. It's an unusual looking manifold with the 1 & 3 runners being unequal in length to 2 & 4. There is no water passage through the manifold, it goes straight to the thermostat. It came with a phenolic (insulating) spacer to reduce heat transfer, too. The manifold I have is the only one I've seen, I don't think the single cam G63B was a very popular tuning platform in Japan, but they do exist.

I found an HKS turbo plenum (more of a box) for blow through DCOE turbo setups, too.

I always promise to take pics and message people back but I am so forgetful and easily distracted by shiny objects and lights. I will try to take pics this weekend and show you guys.

[dash]

sounds like a cool uber rare part

There is no water passage through the manifold

yeah, I couldn't c eliminating coolant flow thru an intake causing probs.
Many folks block off throttle body coolant lines with no issues
It's not like oem was sending so much coolant(=heat) thru a mani

[geezer101]

sounds like a cool uber rare part

yeah, I couldn't c eliminating coolant flow thru an intake causing probs.
Many folks block off throttle body coolant lines with no issues
It's not like oem was sending so much coolant(=heat) thru a mani

Noahwins had better keep his word on this one. I know a bit when it comes to the rarer Mitsubishi stuff, but I had no knowledge of a twin DCOE set up for the G63B existed (obviously...) Yeah you are right - there is bugger all coolant flow going through the stock manifold but the manufacturing/design of the carb manifold is mostly the blame (thus the reason why I took a big @ss drill to it) Will it help? - dunno. But any improvement is an improvement...

[elsupremo]

I have looked for a diagram showing the coolant flow in the engine and the intake manifold to try and figure out what can be blocked or must be rerouted.

So far I haven't found one.

[noahwins]

I can only guess Tomoe Shokai made them for a Lancer Boxtype. HKS made the blow through plenum for the J57 Jeep with the 2.6 and the HKS turbo manifold was for the A183A Starion. I'll try to get pics off all this stuff.

[pennyman1]

coolant flow through the intake in the US was to heat the floor of the manifold for emissions purposes so I have heard. It can be blocked off with no ill effects, unless you drive in the winter - then you may want to keep it. You will have to fill both ends of the pipe to get the water to flow correctly, but it is not a big deal.

[noahwins]

Took me one month but I did it!





I'll try to post pix of the HKS surge tank next.

[geezer101]

^and that, ladies and gentlemen - is art... would be cool to make repros of that manifold

[noahwins]

Should look a lot nicer with 40 years of crud and scale blasted off. Going to use the linkage from the John Baker Mikuni set.

If anyone wants to make reproductions, I'm happy to loan it out.

[dash]

So cool to c these old artifacts. Thanks for posting pix

doesn't look toooo hard to fabricate such a g63b intake mani. Bike carbs probably easier
I'd imagine there's hardly enough interest to warrant reproducing that intake, especially nowadays.
Wanna c effort ? Look what this builder did for his 2.0 staz. Lower machined from solid block ?




Yeah, the 2.0 sohc wasn't viewed as a 'performer' it seems, but they rip hard! ....I luv em,
The staz intake in pix had a "small" evo III 16g blowing 28psi thru it.
As one person put it, "if you're thinking of a DOHC conversion, don't ride in that SOHC.... It WILL change your mind"

[pennyman1]

If you plan on blocking the coolant so that it don't go across the manifold, that is only good if you are running a weber carb, otherwise the choke on the Mikuni will stay closed because it is a water choke.

[Drift50]

So reading this. Why not make plates that match the mating surfaces and weld tubes to a Weber carb plate and call it a day? I mean some science to it would be nice but I’ve seen it done with a edelbrock carb on a jag v12

[geezer101]

So reading this. Why not make plates that match the mating surfaces and weld tubes to a Weber carb plate and call it a day? I mean some science to it would be nice but I’ve seen it done with a edelbrock carb on a jag v12

Fair call - it's doable. But you would either need the skills or know someone who is prepared to weld an adapter to the manifold which adds $$$. The adapter is a low dollar solution that doesn't need special equipment to make it work and it's reversible.