I'm having some stalling issues with the Raider. It's an 88 short wheelbase, with stock carb. Seems to be fine under normal driving conditions, and mild offroading, but under load at heavy to full throttle it bogs down and dies. There is no missfire, seems to be more of a fuel issue. Typically happens going up steep hills or through deep mud. I changed the air filter, fuel filter, cap, rotor and wires today (all well needed) but it still does it. I did some searching and I'm going to check compression and the depression chamber tomorrow, but I'm just wondering if there's anything else I should look for.

How old is your cat?

(Not the purring kind, the exhaust kind <img src="/forums/images/graemlins/rolleyes.gif" alt="" />)

forgot to add that. Suspected cat, disconnected it and tried it without, no change (except it was friggin loud)

Without your cat attached, I think you wouldn't have the appropriate back-pressure and that could affect performance. I'm not sure that would be valid test, but I suppose if there was no change (whether positive or negative), it may be elsewhere.

What are your plugs gapped to? Compression check and depression chamber check would be good to look at also.

Did you do a bowl vent valve check? Basically, you plug the hose leading from the charcoal cannister to the bowl vent valve on the carb and see if this helps performance. If it does, it may be that your bowl vent valve on your carb is bad.

Plugs are Bosch Platinum +4's, can't really gap them. The cat being off did affect power a little bit, but the stalling issue didn't change at all. I'll try the bowl vent test tomorrow as well.

Those are them plugs which have 4 contacts instead of the traditional 1 contact, correct? If so, get rid of them and use NGKs. Those Bosch's are crap.

I've had good luck with the +4's in the past, had them in all my GM's, but I may try some NGK's if this persists. Seems to be primarily a fuel issue from what I can tell though.

Do a search on the Mitsubishi forum here for +bosch and you'll see what I mean. I can't speak for their performance in other makes/models, but those Bosch 4-points are da debil for Mitsu 2.6 engines. I used them once in the past before I knew about them, and swapped them back out for NGKs after only a few months. IIRC, they tend to get carbon build-up, obscuring the gaps (despite having four of them).

Ditto on the Bosch plugs, they don't work well in our old motors. On the other hand I suspect your 20 year old carb. Might be time to go over to FCproducts and get a carb. <img src="/forums/images/graemlins/patriot.gif" alt="" />

Checked depression chamber, seems to be working fine. Checked compression,
cyl 1 115 psi
cyl 2 125 psi
cyl 3 130 psi
cyl 4 130 psi
I would think a cracked head or blown head gasket would make a bigger difference than 15 psi.
Checked bowl vent valve- seems to make no difference. I might pick up some NGK's tomorrow to see if that helps, but I'm leaning toward the 20 year old carb myself. I've priced them out and I think that I will be doing the GMod before I spend that kind of dough on a carb. Even if I stick a cam, a carb and a header on my 2.6 it will still be a slug turning 33's, and starions don't seem to exist in canada so a turbo swap doesn't look so good either.