3.0 V6 Sundance-Duster

[Blue Shift]

Just joined, I have a 3.0L V6 Sundance-Duster. It has the Mitsubishi 6G72 3.0L V6 in it. I was looking for a stroker kit to get the internals ready for forced induction. I found one but I wasn't sure it would work (http://www.importperformanceparts.net/imports/strokerkits_mitsu.html). Do you guys know of any very good kits? This one brings it to 3.3L with a .050 Bore, and they claim it adds 45HP.

EDIT: Also forgot to ask, is there a head swap to a DOHC set from another of the 6G DOHC models or do they not bolt up?

[Ondonti]

no head swap, timing belt pulleys cant be attched, different valve reliefs in piston, the stroker kit is a waste of money. Real Stroker kit for 5000 dollars from Ray Pampena if you can use a 4 bolt twin turbo block.

[ShadowFromHell]

I think you've proven to Ondonti that you don't need a stroker either.... lol. Id really like to pick up a 3.0 5spd p body someday. Ive owned every combo p-body made but a 3.0 car...

[Ondonti]

The fake kit has never been used with success. People who know the motor know that making the rod journals smaller is not something you want to do on a 6g72, but what do I know.

[Blue Shift]

no head swap, timing belt pulleys cant be attched, different valve reliefs in piston, the stroker kit is a waste of money. Real Stroker kit for 5000 dollars from Ray Pampena if you can use a 4 bolt twin turbo block.

4 bolt twin turbo block?

[Force Fed Mopar]

Well I think the heads will bolt on, you may have to use different pistons. If you're buying pistons anyway then it's not much of an issue. Be easier though probably to just buy a DOHC engine out of a 3000GT or Stealth, and change what you need to on it. Intake is different, may need to do some sensor rewiring or swapping, custom air intake etc. Not sure about hood clearance but I have seen pics of a full VR-4 twin turbo engine swapped into a Daytona, so I'm assuming it's enough.

Probably the easiest way to get more power is to just follow Ondonti's steps and throw a turbo on the stock engine w/ a good set of forged pistons installed.

[Force Fed Mopar]

4 bolt twin turbo block?

VR-4/Stealth TT block.

[Blue Shift]

Can everything else on it handle a turbo?

[Force Fed Mopar]

Can everything else on it handle a turbo?

The stock engine you mean? Well, you have to change stuff like injectors, fuel pump, etc to keep up w/ the fuel demands. Various other normal na-to-turbo swap stuff. But as far as the engine parts themselves, yes. Stock crank is the same as the TT crank except it is not nitrided. Rods are good too, heads will hold up. Stock pistons will probably hold 3-5 psi ok, Ondonti can answer on that better than me.

Is your car auto or 5-spd?

[Ondonti]

no. 1st gen cranks are all the same as chryslers (cast). 2-3rd gen cranks (1993+) vr4's have forged cranks that were said by the facotry to be nitrided but are actually not.

cast cranks can make gobs of hp so forged is purely a heavier crank that nobody will ever see kinda bling.

[Ondonti]

Well I think the heads will bolt on, you may have to use different pistons. If you're buying pistons anyway then it's not much of an issue. Be easier though probably to just buy a DOHC engine out of a 3000GT or Stealth, and change what you need to on it. Intake is different, may need to do some sensor rewiring or swapping, custom air intake etc. Not sure about hood clearance but I have seen pics of a full VR-4 twin turbo engine swapped into a Daytona, so I'm assuming it's enough.

Probably the easiest way to get more power is to just follow Ondonti's steps and throw a turbo on the stock engine w/ a good set of forged pistons installed.

Head bolts to the block but you cant run the timing belt tensioner.

[RoadWarrior222]

The fake kit has never been used with success. People who know the motor know that making the rod journals smaller is not something you want to do on a 6g72, but what do I know.

Many failures? Or just fail easy when blown? Coz on the one hand you're saying the cranks are over spec, and on the other you're saying you can't take anything off them. I know you can't have both.

I've still got that crazy scheme in the back of my head to use SR20DET rods on journals offset ground 2mm under, with G54B pistons ground down to flat tops, for about 11:1 CR. Do you think -2 would hold between 250 and 300 all motor, where the -3.25 sucks?

[Force Fed Mopar]

Head bolts to the block but you cant run the timing belt tensioner.

Ah, didn't know that. Thanks for the info :)

[Ondonti]

Many failures? Or just fail easy when blown? Coz on the one hand you're saying the cranks are over spec, and on the other you're saying you can't take anything off them. I know you can't have both.

I've still got that crazy scheme in the back of my head to use SR20DET rods on journals offset ground 2mm under, with G54B pistons ground down to flat tops, for about 11:1 CR. Do you think -2 would hold between 250 and 300 all motor, where the -3.25 sucks?

Dont make 6g72 rod journals smaller. Thats all I can say. They are prone to spinning when people starve them of oil or detonate.

Flattop pistons wont give you anymore then 10:1...which you can buy brand new from topline for 12 valve diamantes. I wouldnt go higher then 11 if you get custom domed pistons, Sunmind on 3si.org is ditching his for slightly lower compression. He doesnt feel the 11.5:1 he has is worth it. Requires race gas and it messes up combustion having the big dome blocking flame propagation. Our valves really dig down into the piston at a fairly shallow angle so the dome will all be in the middle. Not good.

IMO best bet is to get the biggest overbore 10:1 piston you can find. Josh Simon had problems finding oversize 10:1 from his perfered brand so he went with topline I think. The big oversize will probably get you closer to 10.4:1

Nobody has ever used the kit with success. Thats all I know. 8
Pretty much every platform that has a 6g72 disses on that kit. I dont know if they have ever sold one that was installed on any motor except ond that fwdmoparperformance built and hydrolocked (with like zero miles so :P)

[RoadWarrior222]

Hmmm some online piston suppliers are full of crap then, when they give positive dish volumes for the high compression 6G72 pistons. Also seem to have got the idea from those types of places on the data they put on the web that the pistons ended up about .5mm or so negative deck. Some other places had it stated different with an effective compression height of negative 1.5mm or so....

Anyway, all the specs you can dig out of part suppliers online tend to give the impression that there's still piston dish or deck height that could be lost to gain CR.

[Ondonti]

dish = negative.

9.5:1 is fairly high compression and they have a dish.

10:1 are flattop with tiny valve reliefs. If you go any higher it looks stupid cause the dome can only be in the middle between the valves. Rather get the biggest oversize they sell and combine it with a good set of heads from Ed kelly and the Crower cam profile from Chris Grimm that everyone is running.

[Shadow24]

+1 on the low oil spun bearings, been there done that. Although my 24v SOHC has a forged crank stock and 9:1 CR (dished pistons). the 12v can handle low boost fairly well as it has an 8.8:1 CR. if anything, the 3.0 is arguably a better engine if you rev it higher rather than stroke it. its over-square to begin with and with better flowing heads, the bottom end can take you to 8-9K rpms with ease.

just my .02