Turbocharged 340 Mopar

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Turbo231
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Re: Turbocharged 340 Mopar

Post by Turbo231 »

I hadn't thought about using a 318. I guess because it was always in the shadow of the 340. But it does make sense with a turbo, especially as pointed out by Jeff, the walls are thicker which is good with boost. I know people that prefer 4.8L LS engines for the same reason. If I go 318, what heads should I use? Would I have issues with the 2.02 intake valves with the smaller bore?
rebelrouser
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Re: Turbocharged 340 Mopar

Post by rebelrouser »

If you are building a turbo LA engine, the main issue I see is that they only have 4 head bolts per cylinder, from my experience with a procharged 410, based on a 360 is that head gasket sealing is the weak point of the engine. I had to do O-rings and copper head gaskets with ARP bolts. Lots of aftermarket rotating assemblies that are reasonable, on ebay. Main studs, leave the cylinder walls as thick as possible. I used the indy X heads. Settled on 6 lbs of boost with pump gas and a fitech injection system, makes 500 hp on the street.
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Re: Turbocharged 340 Mopar

Post by Justin_inc »

rebelrouser wrote: Wed Aug 08, 2018 9:20 am If you are building a turbo LA engine, the main issue I see is that they only have 4 head bolts per cylinder, from my experience with a procharged 410, based on a 360 is that head gasket sealing is the weak point of the engine. I had to do O-rings and copper head gaskets with ARP bolts. Lots of aftermarket rotating assemblies that are reasonable, on ebay. Main studs, leave the cylinder walls as thick as possible. I used the indy X heads. Settled on 6 lbs of boost with pump gas and a fitech injection system, makes 500 hp on the street.
at 5-600hp IMHO the block is the weak point over clamping force, a good set of ARP head studs, and MLS gaskets will seal up just fine. There is no way you should have to o-ring a block at that power level nor would i invest that kind of money into a stock LA block. We were using a set of home ported Edelbrock performer rpm heads, 10.8:1 compression with a turbo motor never had a gasket issue. Make sure the surfaces are true and straight.
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Re: Turbocharged 340 Mopar

Post by Turbo231 »

I have friends who are strongly suggesting I put a Gen 3 Hemi in the car. 5.7's are readily available (and cheap) now and might be more cost effective in the long run vs. an LA smallblock. What do you guys think?
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Re: Turbocharged 340 Mopar

Post by F-BIRD'88 »

The Challenger (new generation) V6 base motor would be cool in blown form. It will make more power than a 318 340. Lots of availability.
Get the whole engine and trans from a wrecked Challenger.
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Re: Turbocharged 340 Mopar

Post by Ron E »

Turbo231 wrote: Wed Aug 08, 2018 10:53 am I have friends who are strongly suggesting I put a Gen 3 Hemi in the car. 5.7's are readily available (and cheap) now and might be more cost effective in the long run vs. an LA smallblock. What do you guys think?
Just make sure you get a 2009 or newer 5.7. They have the much improved cylinder heads. As a bonus they don't drop seats like the old ones.
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Re: Turbocharged 340 Mopar

Post by Justin_inc »

Turbo231 wrote: Wed Aug 08, 2018 10:53 am I have friends who are strongly suggesting I put a Gen 3 Hemi in the car. 5.7's are readily available (and cheap) now and might be more cost effective in the long run vs. an LA smallblock. What do you guys think?
thats the route my buddy has taken after 3 LA failures.
m880
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Re: Turbocharged 340 Mopar

Post by m880 »

Buick GNX 1 big turbo
agertz1
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Re: Turbocharged 340 Mopar

Post by agertz1 »

Beware, don't use a CAST 318 crank for your projected power levels. At least 318 forged/truck crank. 360 Magnum block has some nickel= good.
OEM roller set-up a plus. Perhaps billet 2,3,4 caps/ angle bolted. Good Luck, Art.
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Re: Turbocharged 340 Mopar

Post by F-BIRD'88 »

If you do a Rear/Remote mounted Turbo set up you avoid all the heat, weld, exhaust issues of a under hood turbo.
Holley STS Turbos
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