So I'm putting a 4 inch crank in my 340. Block has been tanked and measured. Needs to bored .020. I have a forged MP crank, Wiseco forged pistons and K1 h beam rods. What else should I do to the block for prep? Should I spend the money and get the Hughes stud girdle kit for the mains? What should I be more concerned with a windage tray or the girdle? Can I do both? My goal is to have a durable 425 horse street car. Possibly add a turbo down the road. Probably will never happen but I want to build the bottom end to handle what ever. Only doing it once. I would like to use the Milodon road race pan,pick up and windage tray but not sure if it will work with the girdle?
340 stroker build questions
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If you are planning to add power adders later on then I would suggest the girdle which comes with studs for the mains. You can use a crank scraper In the oil pan. Fitting a windage tray would be difficult with the girdle not to mentioned the increased stroke. Also look at the thread on oling mods by Guitarjones. Well worth the effort for your future HP increase.
1970Duster
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I've got the milodon road race oil pan with a Teflon bladed crankscraper (up and down stroke) and a stud girdle all in my 340 with no problems. That said I'm using a stock stroke setup.
Also if you're stroking it, why not drop in a 4.250 in stroke crank (or was it 4.125)? Go big or go home.
Also if you're stroking it, why not drop in a 4.250 in stroke crank (or was it 4.125)? Go big or go home.
Girdle is a waste of money. Guys with 550 and 200 shots aren't running girdles. Even turbo cars... no girdles. Spend $ elsewhere
Depending on the pan you use, a windage tray is another leave it out item.
Depending on the pan you use, a windage tray is another leave it out item.
moper
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x2 yup
Stud the mains, and replace the caps 1-4 with Program 2bolts - and that's about as good as you'll get in a factory block. If you still don't feel that's safe for you, buy a real block.
EL5DEMON340
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Should do the oil gallery mods where you open up the mains, also the oil pump porting mods.
The bigger stroke cranks have less over lap between the mains and rod journals. They only make those cranks for a 360 main size. The 340 main doesn't have enough over lap for the stroke. I work for a dodge dealer and can get any parts in the performance catalog below cost. No big stroke cranks in there.
Never had a stock main bolt break. These aren't chevies with whimpy main cap/bolt set ups. If you want to hit it with more than about 550, put a set of studs in and have the block line honed if necessary.
The no 340 main 4.25 crank is not correct. Vic Bloomer/BPE have them. Plenty of 4.125 and some 4.25 cranks with 340 mains are available.
http://www.forabodiesonly.com/mopar/showthread.php?t=128845
I had no idea they were making those. Thanks
With a target of only 425 HP, which is just over one HP per cube; your crank, rods, and pistons should give you a durability level almost half again of that number. As a suggestion of what more to do to the block, have the lifter bores trued and sleeved, main studs.
autoxcuda
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No reason to have the lifter bores trued and sleeved for a 425 HP 4" stroker motor:
Main studs if you wish or new cap bolts.
A cast Scat crank would be perfectly fine for this too.
But a turbo down the road would need a forged crank, studs, and more. But you are going to need pistons or heads changed for that to lower compression. So you are not going to just bolt on a turbo and go (like that would happen anyways)
What's the reality of parts that cant' be used on 425 HP stroker motor parts with a stroker turbo motor?
Why not just port some X heads and get 425 outta a stock bore and stroke 340?
autoxcuda
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So you don't have to run a bigger (relatively) cam in the 340.
Or the same cam will be made more tame in the stroker with smother more quiet idle and more street friendly.
And the stroker will make the same HP and TQ at lower rpm levels that is less taxing on the valvetrain and less necessary for expensive valvetrain parts.
This is exactly my goal. More horse power and torque at street friendly rpms. This build may end up being more like 475-500 horse I really not sure how much power it will make when done. I'm focusing on building a bullet proof short block for now. I'm planning on edelbrock heads roller cam ect. What should I be doing cam wise? I have -20cc pistons that will be at 0 deck.
Yeah I know all that hooha. But a high revving screamin 340 is a LOTTA fun. I've had several.
Boy you got that right, I had one in a 69 Dart and was that car a blast.
I have a 416 same dish pistons, scat forged crank I beam rods, roller voo doo cam, ported eddies, victor intake, small tti header, made 583 on dyno, so your plan is hp with no prob, I had it line honed and studs in bottom with oil mods, so far so good, according to the port work on your heads will determine a lot on the hp, the air gap, will have a better torque curve and wont be off hardly any on power from the single plane intakes, to me air gap is best, voodoo makes some diff size rollers and the smaller is more streetable, but cubic inch makes bigger lift more streetable, mike at mrl has killer roller lifter set up and can steer you in the best direction for your cam and any other mods, and is hands down good to deal with, I would give him a call , good luck on your combo, from what your sayin you goin to be extremely happy with your hp
autoxcuda
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Plan the whole motor NOW. Why wait?
Stock caps, new capbolts, forged MP crank and your parts listed will be bullet proof in a 425 HP motor. Not bullet proof in a 600 HP. And ticking time bomb in a 700 HP motor.
Then buy the appropriate parts to match you goal. Otherwise you have a discontinuous curvy path to an another wise straightforward destination.
475 to 500 HP is going to come from a good heads and probably with mild cleanup and something cam wise in the range of a XR280HR-10 or XR286HR-10
. Not recommending those cams, but just a starting/launching point for other brands or custom grinds.
-20 cc deck will be about 9.9/10.0 to 1 compression with the smaller "63cc" head (measures 65cc) with a 340 block. My stroker motor has the Icon -21cc pistons that give me a measured 9.8:1 compression with 0.20-.25 quench with a 0.030 over 340 block. I can run 91 octane Arco gas without pinging under heavy load hot day and 32 degrees total advance. More advance and it will ping.
I love an engine with a good top end power band. My car with 3:55 gears and auto trans is fun but I think to take advantage of a high rev small block you need a manual trans to go with it. The higher you rev an engine the shorter its life span will be. I want something that will last a long time and have good driveability.
A 408 with a decent set of ede heads, air gap and voodoo 268 will make 475ish... Same with a set of RHS X heads.
No need for a roller cam if it's not in the budget.
No need for a roller cam if it's not in the budget.
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