Biggest Small Block Stroker

[1970GranCoupeConvert]

Hey there Power Freaks,

I have a stock small block 340 with the cast iron 202 heads and the cast iron "high performance" exhaust manifolds and full exhaust with resonators (but it has chrome tips). 

I like my current setup because it has painted stock sheet metal valve covers and stock cast iron heads...so it looks stock and makes such high horse power that the 4 banger turbo rockets can blow my door off...

I see lots of BIG inch stroker advertisements (way up to 450 CID) and I get stroker envy when I read advertisements about their big displacement...

So...I guess the question to the masses out there for those who are "in the know" (I am so far out of the know since I did a full restoration on my Barracuda in 1992...geez I had to use a thing called a telephone back then)...

What are the stroker options out there for the stock 340 engine?

I would prefer the "stock" look...I do not race this car (my first car that I have owned since 1984)...I just like the "quiet" sound of my stock cast iron "high performance" exhaust manifolds.  I really do not want the modern look of the cool aluminum "CNC bling" and all of that fancy "get off my lawn you young whipper snappers with your pants hanging down around your..Zzzz...Zzzzz...Where waz I...Oh yeah and all of that fancy shiny crap...when I was your age we used to race our cars uphill both ways to get to school...Zzzz...Zzzz...

What I would really like is a HUGE...real man Lord Farquaad castel...over compensating Bi Gassed stroker that can use my existing 202 intake heads, real man oil leaking sheet metal valve covers, and exhaust manifolds that will hide a major roller cam and all of the internal bling Sh-tuff that makes the big power numbers so I can choke it all off with my old school heavy metal downstream crap...

Any suggestions???

THANKS!!!

Back in my day bananas were for eating...not dancing...

[Chryco Psycho]

I guess it depends how long you want the engine to live , , I like reliable strong engines , I try ti maintain rod ratio as I believe it is more important than CI overall .
Once you lose rod ratio the efficiency drops , you can move the pin much higher in the very tall Mopar pistons so you can use long rods & maintain ratio .
What I would do is save the 340 block , pick up a 360 LA roller block 88-92 , build it to 408 CI , I would go to 426 max ,  use a roller cam , save your factory lifters if possible , get the compression up & Make sure you have quench with a good closed chamber head & you can make crazy power , , A 340 with W2 heads can get into the 750HP range !!

[RzeroB]

Interesting question.

If I'm reading it right, the OP wants to keep the factory 2.02 iron heads and exhaust manifolds. Okay, but in doing so you will limit the potential of what the stroker is all about ... moving more air through the engine to make more power.

With the iron heads and exhaust manifolds maybe something modest like a 372" kit that uses the 360's stroke length of 3.58" would give you the most bang for the buck??

[Shane Kelley]

Those exhaust manifolds are going to be the real choke point. You can port those heads to flow decent numbers but those manifolds will pretty much negate those efforts. Whatever route you go I would highly recommend some good headers. 

[gzig5]

I think a 340 can go out to approximately 440ci displacement with a 4.250" crank.  Doing so with stock heads is an exercise in futility. Now the FAST crowd https://www.fastdrags.com/ does this but they are spending mega-bucks to port the intake and exhaust tracts within an inch of their life to get flow that produces HP.  That's how you get a small block duster into the 10's with an engine that looks like it came from the factory in 1970.  Going to a stroker crank will give you a lot more torque and HP than the stock motor has, but keeping the cast iron heads and intake stock is going to strangle it.  FWIW, painted aluminum looks the same as painted iron. 

[7212Mopar]

All depends on what HP you want when done. You can build a 440 CI SB stroker, keeping the stock or ported CI heads and CI exhaust manifold and be around 400 to 425 HP range. I think going beyond that like more than 1 HP per CI will need to move air in and out more efficiently with non stock components.

[Mopsquad]

If getting beat by those late model imports is part of your motivation, you have to consider how that new found power is going to be useful ex. traction.  I weekly see those imports easily handle the 500HP classic muscle at the 1/8 mile tracks which is like a street race.

[HP2]

Out of the starting blocks, no one is faster than Usain Bolt.  But if he is breathing through a garden hose, he will be spent after 10 strides.

Engines are simply a complex air pump. The more air you pump through it, the more efficient it is and that efficiency is limited to the tightest restriction. Yes, as others have said, the FAST guys use stock parts, but they have done extensive and expensive porting on these parts to match flow capability with their engines. As such, while appearing stock, they may also have compromised the stock longevity of these components.

[1970GranCoupeConvert]

THANKS for all of the information guys...greatly appreciated.

>FWIW, painted aluminum looks the same as painted iron.

Most of the new CNC heads that I see look like chunks of shiny aluminum with straight sides.  Does someone make aluminum heads that have the cast appearance?  I would not be opposed to this.

I do like the looks and sound of the cast "high performance" KaZaust manifolds.  They do look really rough cast on the inside...

[DeathProofCuda]

Since you are interested in going faster, have you taken your car to the track yet to get a baseline on where it is currently running?

[JS29]

Gear's make a difference in your takeoff or top end.   

[RzeroB]

Most of the new CNC heads that I see look like chunks of shiny aluminum with straight sides.  Does someone make aluminum heads that have the cast appearance?  I would not be opposed to this.

True and even painted it's a giveaway that they're aluminum. However, I imagine you could probably bead-blast the exterior to give it a nice cast-iron like texture??

[autoxcuda]

Most of the new CNC heads that I see look like chunks of shiny aluminum with straight sides.  Does someone make aluminum heads that have the cast appearance?  I would not be opposed to this.

True and even painted it's a giveaway that they're aluminum. However, I imagine you could probably bead-blast the exterior to give it a nice cast-iron like texture??

Small block aluminum heads have huge flat area of added material. It sticks out like a sore thumb.

You'd have to Cnc a lot a material off and fine cnc a texture, then sand or slurry sand blast them.

[1970A-66Challenger]

I believe Indy Cylinder Head is selling the former RHS cast iron head which looks fairly stock. Take a look at IMM Engines website or talk to Brian at IMM.

http://indyheads.com/images/maxlaxnewproductlinK.pdf

[tparker]

hey, have fun with it. I just stroked mine to 416. But I'm confused. Why do you want a big ass motor, but keep everything stock? I don't get it. I get stock and I get sleeper. I even get keeping stamped valve covers since they don't produce HP. I wouldn't worry about a bigger motor if you can squeeze a lot more out of the one you have. But that's just me. Either way, can't wait to see what you end up doing.