331-354 Stroker combinations, post yours

Discussion of the 331-354-392 HEMIs.

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Bailiesdad
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Joined: Sat Dec 01, 2001 6:00 pm
Location: Maryland

331-354 Stroker combinations, post yours

Post by Bailiesdad »

I was asked to post my specifications on my 5/8 inch stroker in my 354.

Here they are for the 426 short deck early hemi:

Crank is full journal size and width, Chrysler mains and rod journals. Federal Mogul bearings all the way. Stroke is 4.25 It was fully counter weighted and balanced with Mallory metal with hard chromed journals. Very strong and durable.

Rods are full Chrysler length 354 rods 6.625 that were polished and boxed for added strength and custom ARP 2000 rod bolts and nuts were used for added clearance and strength. I tried to use longer rods but the pistons were too short, the pins were up into the 2 nd ring groove.

Pistons were custom made Wiseco for 10 to one compression. Pins are stock .984 200 thick straight wall..(There were no stock pistons that would work in the motor.) Ring sizes are 1/16 1/16 3/16 so I could use the racing nascar gapless rings. The finished bore is 4.005.

The block and oil pan had to have very little material cut out for clearance and all the full Chrysler sizes and tollerances were used.

Anyone need any other info don't hesitate to ask, I will post it for you.
Moparlee
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Location: Carthage, MO

Post by Moparlee »

Sounds cool, what will this be going in? Will it be a blower application or?

Lee
392 Hemi
354 cracked and needs a sleeve
241 or 270 the only running one I have
340/E-brock heads/six-pack/4-speed/mini tubed/spool-64 Valiant
budmspeeco
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Joined: Tue Dec 21, 2004 5:35 pm
Location: South Houston, Texas

331/354 stroke combinations

Post by budmspeeco »

I am working on a 354 to go to Bonneville in 2006. It is going in a roadster. The C.I. limit we are trying to get under is 377 ci. The block is bored .090, using a +.030-392 piston. The distance from pin center to the deck is 1.750. It has a .720 dome. The crank is offset ground for a big block rod to a 3.670 stroke, up .040 above the stock 3.630. They are 6.800 long with 2.200 journal size and a .927 pin.. It works out to 374.50557 c.i.. Probably injected ,maybe alcohol to run cooler. I may build a tunnel ram if an injector set does't come along at the right price. Also have a 392 with a 4.250 stroke on it now. May cut it down to big block and offset grind for another 1/4 inch stroke. Is there any reason hemi guys are not taking advantage of all the chevy rod combinations when building their engines. Looks like a given. Start with a std.size bearing and more cubes. Just order the pistons and pins to match. 8) Buddy
'48 anglia
johnny5
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I agree

Post by johnny5 »

I'm going with the 2.200" pin, 6.800" long BBC Eagle H-beam rods and an offset ground 392 crank to turn my 331 into a 402. I figure the rods are about as long as they can go without making the pistons too short. The rod/stroke ratio is 1.70 which should keep the torque high. It's all I need for the street.
Bailiesdad
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Re: I agree

Post by Bailiesdad »

johnny5 wrote:I'm going with the 2.200" pin, 6.800" long BBC Eagle H-beam rods and an offset ground 392 crank to turn my 331 into a 402. I figure the rods are about as long as they can go without making the pistons too short. The rod/stroke ratio is 1.70 which should keep the torque high. It's all I need for the street.
Chrysler did not reccommend turning a stock crank more than 30 under, what do you think taking it 175 under does to it, :o use Chrysler parts with a Chrysler and leave the chevy stuff to the chevy guys. :roll:
johnny5
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it works, don't knock it til you try it

Post by johnny5 »

:roll: People have been doing this for years with the old hemis (331/354 bored and stroked to 392-402) and to turn low deck B motor 400's into 474's. Shaving down the big, heavy Chrysler journal to 2.200" makes it lighter, you can use virtually any rod you want, and it allows you to correct any imperfections in the factory forging (indexed throws). You can also use any off the shelf BBC bearing.

All 392 cranks started out as the same chunk of steel from a foundry that was cut down to a certain size. Cutting it down further to a proven safe journal size makes no difference.

The reason for not going any further was to avoid using too thick of a bearing shell. If it gets too big, the crush is unpredictable once torqued and you may end up with an out of round rod bearing! This is eliminated by going to a smaller standard size journal with a connecting rod designed to accept it.

The BBC rod journal size holds up pretty well in a crappy rod/stroke ratio Chevy 454 blower motor making 1000+hp. I agree with budmspeeco. Taking advantage of this option in the short deck 331-354 stroker gives you a much better rotating assembly than with the old school way of doing things. I won't build a motor with weak old rods and a fully counterweighted crank. It doesn't make sense with the modern components available today.
Bailiesdad
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Re: it works, don't knock it til you try it

Post by Bailiesdad »

johnny5 wrote::roll: People have been doing this for years with the old hemis (331/354 bored and stroked to 392-402) and to turn low deck B motor 400's into 474's. Shaving down the big, heavy Chrysler journal to 2.200" makes it lighter, you can use virtually any rod you want, and it allows you to correct any imperfections in the factory forging (indexed throws). You can also use any off the shelf BBC bearing.

All 392 cranks started out as the same chunk of steel from a foundry that was cut down to a certain size. Cutting it down further to a proven safe journal size makes no difference.
Totally incorrect, if Chrysler engineers had designed the crank for 2.20 rod journals the engines would have that size, now some guys are "reengineering" stuff to try and save worn out parts and money. (All chebby guys try to do this.)

Never seen a record holding or setting Hemi with chevy junk in it. The Chevy stuff will not hold up to the power level that a full race prepped hemi puts out.

The fuel guys even go larger on the main journals....DUH
johnny5
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say what?

Post by johnny5 »

You think they never improved anything over the years? That's why you don't see any modern engines with ridiculously huge ROD journals (ie 392 hemi size) that add frictional drag and rob horsepower. Nostalgia fuelers use larger mains so they can use stock (read - cheaper and more available) 440 main brgs. They still cut down the rods.

Oh, and BTW, the "record setting" powerplants are using 426 based motors, not early iron. Look a little harder next time.

I'm building a street/strip motor that will do just fine with the 450hp it'll make. Regardless of what you think, the same short block could be used in an 800+ horse blower motor, not that most rodders have that much power between the fenders.

PS: duh.
Jake
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Post by Jake »

Hey Johnny,
What bore and stroke do you end up with in that 331 to make 402? Just wondering because I'd like to make a high pressure thumper out of a 331. My initial plan was to go with a blown injected 331 and try to get to 700-800 streetable HP for a Willys coupe. In terms of a crank, I was thinking of having a non twist forging or a billet crank made for it and saving a factory crank for the restorers. I really wanted to go with the early block and heads because it would be more "period correct" for an old school gasser type Pro Street car. I haven't been around any of this early stuff since the late 60s and early 70s and even at that it was all 392 stuff. I was told that 800 streetable would be difficult to attain by a reputable person so then I changed gears and started looking at aluminum 426 stuff that I am more familiar with now days. I have a 518 blown injected alcohol K.B for funny car stuff and I understand the technology involved there. If you get a chance, please let me know your thoughts on getting to 700 or 800 hp with a 331. Thank you.

Oh yeah, I understand and agree with both of your guys arguments. Its no secret that the PRO STOCK guys are using Honda pins now for the reasons you outlined and I understand and agree with Dad's "old school" thoughts as well. I am just torn lol.
Bailiesdad
Posts: 433
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Location: Maryland

Re: say what?

Post by Bailiesdad »

johnny5 wrote:You think they never improved anything over the years? That's why you don't see any modern engines with ridiculously huge ROD journals (ie 392 hemi size) that add frictional drag and rob horsepower. Nostalgia fuelers use larger mains so they can use stock (read - cheaper and more available) 440 main brgs. They still cut down the rods.

Oh, and BTW, the "record setting" powerplants are using 426 based motors, not early iron. Look a little harder next time.

I'm building a street/strip motor that will do just fine with the 450hp it'll make. Regardless of what you think, the same short block could be used in an 800+ horse blower motor, not that most rodders have that much power between the fenders.

PS: duh.
Current Record holders use these....I don't need to look to hard. I was reffering to old records but good point they used same.......rod journals

Stock 426 2.3750 rod journals (NOT 2.200)(NOT 1.800)
Stock 426 main journals 2.750 fuel to 3.0
Used in KB TFX Milodon INDY MAX after market blocks to 572 cubic inches with 4.80 bore centers and much larger for the mountain motors with 5 inch bore spacing.

The guys LOVE you guys that turn down their cracked cranks down to 2.20 for the street.

440 bearings in a Hemi, another budget minded myth??? I use Clevite 77 in new 426 style and Fed MO on the earlier engines. Fully radiased cranks don't like much else.

If you have a Chrysler stay with Chrysler specs, as to getting 2.4 or 2.5 hp per cubic inch out of an early Hemi headed engine it will be very difficult. Remember the formula for cu inch air flow /per HP.
Jake
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Post by Jake »

Thanks, I guess I could go with the HH aluminum heads and try and make em look like cast lol. I dont really have any idea what the 331 heads flow or how far the block can be bored but maybe I'll get the block sonic checked and go from there. I was just kinda wondering about his bore/stroke combo so I could explore those options.
TrWaters
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2.2 journals

Post by TrWaters »

If there is any doubt, go to the Moparts board (if you can :lol: ) and ask how many Mopar guys use 2.2 rod journals. It is common practice, and you can get any length I or H beam rod, from any company with a 2.2 journal. And trust me, an after market Crower or Carrillo rod is MUCH stronger than any stock hemi rod. Or shop around on ebay for some good stuff cheap :lol:
Early hemi to late sb Mopar trans adapters. Precision billet parts for early hemis.
Bailiesdad
Posts: 433
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Location: Maryland

Re: 2.2 journals

Post by Bailiesdad »

TrWaters wrote:If there is any doubt, go to the Moparts board (if you can :lol: ) and ask how many Mopar guys use 2.2 rod journals. It is common practice, and you can get any length I or H beam rod, from any company with a 2.2 journal. And trust me, an after market Crower or Carrillo rod is MUCH stronger than any stock hemi rod. Or shop around on ebay for some good stuff cheap :lol:
The practice of following what other people do is a sure way of making large errors, all the rod manufacturers make Chrysler sized rods if you are concerned about the strength of the stock rods.

Some people need lots of help when it comes to doing much of anything on their engines and the best way to get the correct information is to check with expirenced engine builders not the internet for bargain budget rebuild guys. Those rebuilders are limited by funds and try all sorts of strange combinations.

Tom Waters is right you should determine what is good stuff by doing your home work and buy it cheap. That way you do not end up with cheap stuff, that has been modified and is unusable. You also don't purchase items that are new to the market and are way over priced.

Chrysler engineers determined the sizes to handle the power generated by the Hemi engines and aftermarket manufacturers make those parts to Chrysler sizes to stronger tollerances.
Last edited by Bailiesdad on Fri Jan 13, 2006 7:17 pm, edited 1 time in total.
TrWaters
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Post by TrWaters »

We all know the old saying about opinions :o

Mr Ripley is correct in one aspect. One thing holds true. If you dont do your homework, you really have no one to blame but yourself if something goes wrong.
Early hemi to late sb Mopar trans adapters. Precision billet parts for early hemis.
johnny5
Posts: 128
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Location: St Charles, MO

Post by johnny5 »

Jake wrote:Hey Johnny,
What bore and stroke do you end up with in that 331 to make 402? Just wondering because I'd like to make a high pressure thumper out of a 331. My initial plan was to go with a blown injected 331 and try to get to 700-800 streetable HP for a Willys coupe. In terms of a crank, I was thinking of having a non twist forging or a billet crank made for it and saving a factory crank for the restorers. I really wanted to go with the early block and heads because it would be more "period correct" for an old school gasser type Pro Street car. I haven't been around any of this early stuff since the late 60s and early 70s and even at that it was all 392 stuff. I was told that 800 streetable would be difficult to attain by a reputable person so then I changed gears and started looking at aluminum 426 stuff that I am more familiar with now days. I have a 518 blown injected alcohol K.B for funny car stuff and I understand the technology involved there. If you get a chance, please let me know your thoughts on getting to 700 or 800 hp with a 331. Thank you.

Oh yeah, I understand and agree with both of your guys arguments. Its no secret that the PRO STOCK guys are using Honda pins now for the reasons you outlined and I understand and agree with Dad's "old school" thoughts as well. I am just torn lol.
You need a 4.00" bore and a 4.00" stroke. The 331 should be able to take it because the cylinder walls are about 3/8" thick. I'm not talking about building a competition blower motor, just a good reliable 450-500 horse street/strip combo. Competition engines don't use anything stock except for the block, and MAYBE the heads anyway so the point is moot.

It would be foolish to use stock 354/392 rods in any modern rebuild. The new Eagle, Crower, Manley etc etc etc rods are lighter, stronger and just plain better. Save the stock rods for the "economically challenged" rebuild. Whether you like it or not, using a 2.200" rod journal in a 500+hp big block is not an internet theory, it's been used quite successfully in Chevy motors, naturally aspirated, blown, and sprayed for about 40 years in thousands and thousands of engines. It doesn't take a rocket scientist to figure out this is a good idea.

As far as getting 700-800 horses out of a 331 with iron heads, that's approaching blown gas levels. 600-650 is a better goal. You don't need to stroke it. I'd go with a little less boost, use the stock 331 crank (prepped and lightened) and as little overbore as possible (stock 354 size max) to keep the cylinder walls good and rigid. Billet steel 2-bolt caps would be a really good idea! But then again, if you have a blown fuel KB hemi, maybe I should be asking you for advice :wink:
Bailiesdad
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Post by Bailiesdad »

"it's been used quite successfully in Chevy motors"

and they have been chasing hemis :D

Blown KB Hemi no, but nat aspirated KB 575 Cu In Hemi yes.....blown stroked 392 based hemi yes, fuel injected stroked 354 based hemi yes........all with stock Chrysler Journal sizes, max .010 undersized.
Jake
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Post by Jake »

O.K. thanks for all the input guys, I do appreciate your time. Now I better go take a nap and sleep on it a little.
johnny5
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groan...

Post by johnny5 »

Bailiesdad wrote:"it's been used quite successfully in Chevy motors"

and they have been chasing hemis :D

Blown KB Hemi no, but nat aspirated KB 575 Cu In Hemi yes.....blown stroked 392 based hemi yes, fuel injected stroked 354 based hemi yes........all with stock Chrysler Journal sizes, max .010 undersized. All without the censoring moderators' parts or Tex Smith tips.... :roll:
Look, you asked "331-354 Stroker combinations, post yours". I did. If you don't like it tough luck. I know what I'm doing. It's lighter, stronger and more reliable in the long run as a street/strip/rod motor than your combo. Period. Put that in your pipe and smoke it. Everything you've quoted has nothing to do with building an early stroker hemi. Most people don't race these things anymore because the late hemi has it beat hands down, so I don't know why you keep talking about old racing records and then mixing up the engine families.

The simple fact is:

All of your replies don't really have anything to do with the points everyone else has brought up. All you're doing is spewing out random rhetoric and arguing irrelevant and totally unrelated topics. If you do some reading and listen once in a while, you might just learn something.

I'm signing off of this thread. It's got nothing I need to do my thing 8)
Bailiesdad
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Post by Bailiesdad »

Johnny if you think that early Chrysler hemis had 3/8 thick (.375) thick cylinder walls you are mistaken. I have seen very few that would take more than .075 over bore.

Taking even a 354 to 4 inches is .0625 approaching that limit. All low deck early hemis should be sonic tested to make sure they are safe at 4.00.

If the blocks had cylinder walls .375 thick you could easily take them out more than twice that amount, a 392 could go to 4.125 leaving a very safe .250 wall...

You also suggest taking .175 off the rod journals on the cranks when Chrysler would replace a crank when it was .030 under. I will listen to the Chrysler engineers....
budmspeeco
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331/354/392 bore/stroke combinations

Post by budmspeeco »

" If the blocks had cylinder walls .375 thick you could easily take them out more than twice that amount, a 392 could go to 4.125 leaving a very safe .250 wall..." If you bore any cylinder to 4.125 after beginning with a wall thickness of .375 you will still be left with a wall thickness of .3125. The wall thickness is reduced only 1/2 the bored dimension.. Those that are giggling whether a hemi runs better or worse with Chevy parts are being childish. You are humanizing parts. It is an inanimant object. It does not know what kind of engine it is going in during assembly. The ability of a single part number to be used in multiple applications only makes that part a less expensive item to make and a more competitive price in the marketplace. Why do you think Chevy parts are so cheap vs. hemis. Production cost. If as many Chrysler hemi rods were made and sold as Chevy the cost would plummet for the Chrysler stuff. Just because Chrysler engineers used 2.375 rod sizes does not mean the new technology AND incredible lubricants we now have should not be adapted to these old motors. If you study the physical diameter of a welded stroker rod journal you realize a substantial part of the inner side of the original journal was cut away to make the outside of the new journal farther away from the crank centerline. The inner material is as good as the stuff on the top. Stock journals may have gone through a small heat treat at the factory a few.000s thick. Factory dictates were not to disturb that thickness as well as to not have too thick a bearing as explained by another fellow. Look at the processes a crank can go through now & you are comparing apples to oranges. I wanted to buy a street hemi when I was 25,old enough to finally have my insurance on par with other male drivers. I did not because Chrysler's policy was once it left the showroom it was yours. The biggest rumor I listened to though was that 426 cranks could not be turned if they had a problem. I missed having a street hemi because I was afraid of hurting the motor with no warranty. I guess if I HAD bought one and it broke down it would still be in my Dad's garage with 3000 miles showing and a bad crank.I SHOULD BE SO LUCKY!!!!!
8) 8) 8)
'48 anglia
johnny5
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Post by johnny5 »

Bailiesdad wrote:Johnny if you think that early Chrysler hemis had 3/8 thick (.375) thick cylinder walls you are mistaken. I have seen very few that would take more than .075 over bore.

Taking even a 354 to 4 inches is .0625 approaching that limit. All low deck early hemis should be sonic tested to make sure they are safe at 4.00.

If the blocks had cylinder walls .375 thick you could easily take them out more than twice that amount, a 392 could go to 4.125 leaving a very safe .250 wall...

You also suggest taking .175 off the rod journals on the cranks when Chrysler would replace a crank when it was .030 under. I will listen to the Chrysler engineers....
331's had bores that thick. I can mail you the chunk of wall I have in my toolbox for a modest fee. The bigger the bore got, the thinner the walls got. Common knowledge. Same as making a stroker crank for a 331/354 out of a 392. Call me when you've actually built an engine and not just rattled off stuff out of a 50 year old service manual.
desotoman
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Post by desotoman »

Bailiesdad,
You better check the rule book. I believe the rules for Bonneville "C" engine class is 306"-372". If you are going to be at 374 cubic inches you will be at the bottom of the "B" class that goes from 373-439. At least that is according to the 2006 rule book. Good luck.
desotoman
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Post by desotoman »

Opps, that last post was for budmspeeco. Sorry to Bailiesdad.
Bailiesdad
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Post by Bailiesdad »

331s did not have cylinder walls .375 thick, 354s did not have cylinder walls .375 thick, 392s did not have cylinder walls .375 thick.

I have sonic checked a 100 or more and NEVER seen a consistently .375 thick cylinder wall on any hemi engine.ever. I would love to see a sonic test done proving your assumption....

I have had to sleeve 354 blocks that went over 4 inches because there was not .180 left in the wall after boring. The new sleeves were only .125 thick..........

When I use a stroker crank I buy billet steel aftermarket crank, not modify a stock crank.

The econo way to do it, cutting up a 392 crank for a 4.00 stroke, is not nearly as strong and reliable but it is cheaper....but why spend 300-400 bucks to cut up a 40-50 year old crank, then expect it to hold 500-600- 700 hp?
johnny5
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?

Post by johnny5 »

Once again:

I have a piece of cylinder wall from a 1954 331 in my toolbox.

It's .375" thick +/-.005". I don't have to sonic check it. My micrometer works just fine. Why don't you just post some of the hundreds (a highly believable number) of sonic numbers you've supposedly pulled? You don't have any, that's why :roll:
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