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SB stroker options for track car #432206 08/09/09 01:13 PM 08/09/09 01:13 PM
Joined: Jan 2003 Posts: 30,992 Oregon A AndyF OP I Win
AndyF OP I Win A Joined: Jan 2003 Posts: 30,992 Oregon	I'm looking into a project where we would build up a SB for an A body track car (road race). It isn't an all out effort, just a big fat torque curve so the guy can drive to the track and pull 130 mph down the front straight. We have a couple 360 blocks but there doesn't seem to be a lot of options for 4.0 inch cranks with the 360 mains. I'd like to run a Chevy 2.10 pin so I can use a Chevy connecting rod. (The Chevy rods are less expensive and there are more bearing options plus the smaller piston pin is lighter, etc.) The other option would be to pony up for a 340 restoration block and then go with a Callies crank with the Chevy pins. Or I suppose one could use bearing spacers but I don't like that idea. I'm not having too much luck finding bobweight info on the various cranks that are for sale either. Maybe I have to call the vendors to find out if these cranks will balance internally or not? The bobweight should be down around 1800 grams or so with a 6.125 rod, .927 pin, 15cc dish piston, etc. Lots of rings available at the various 4.00 oversizes so we'll probably run 1.5/1.5 or 0.043/0.043 just to take a little more weight and friction out of the assembly. Any other options out there that I need to think of?

Re: SB stroker options for track car [Re: AndyF] #432207 08/09/09 01:21 PM 08/09/09 01:21 PM
Joined: Jan 2003 Posts: 5,484 SoCal Brian Hafliger master
Brian Hafliger master Joined: Jan 2003 Posts: 5,484 SoCal	I would use a Scat 4" crank, 360 mains if your sticking with the stock block. Your not saving a ton with chevy rods and pins IMO. What kind of cam (FT or roller or hyd roller)are you planning? RPM? Any rules? I love building road race and circle track engines...they are a nice challenge and fun to watch go around the track. Still waiting for my book Andy LOL!! Brian Hafliger

Re: SB stroker options for track car [Re: AndyF] #432208 08/09/09 01:35 PM 08/09/09 01:35 PM
Joined: Jun 2003 Posts: 52,972 Romeo MI MR_P_BODY Master
MR_P_BODY Master Joined: Jun 2003 Posts: 52,972 Romeo MI	Go with the cubes, I'd use a 340 base for the bigger bore. Something in the 4.10 gear range with a 28" tire You might even offset grind a 4.0 Mopar crank

Re: SB stroker options for track car [Re: Brian Hafliger] #432209 08/09/09 01:39 PM 08/09/09 01:39 PM
Joined: Jan 2007 Posts: 3,695 nc E emarine01 master
emarine01 master E Joined: Jan 2007 Posts: 3,695 nc	I wouldn't rule out the 3.79 cranks for a road race combo, still has good grunt down low with higher rpm potential,

Re: SB stroker options for track car [Re: MR_P_BODY] #432210 08/09/09 01:48 PM 08/09/09 01:48 PM
Joined: Apr 2005 Posts: 1,880 USA Ron Silva top fuel
Ron Silva top fuel Joined: Apr 2005 Posts: 1,880 USA	http://www.ohiocrank.com/mopar_cranks.html Watch the scat cast cranks, because the back flange could be machined too far back. I have heard from several different places about this and problems arising from it. AND: the crank in my 406 Crate wiped out the thrust bearing/flange because of this. You end up with insfficient "converter pull up" and when the engine runs and is warming up and things start to expand it binds up and the problems start. I belive the crank in this Crate motor is a scat cast crank. SRT DEMON ONE SEAT

Re: SB stroker options for track car [Re: AndyF] #432211 08/09/09 02:13 PM 08/09/09 02:13 PM
Joined: Jan 2003 Posts: 1,402 Littleton Colo G Geezer pro stock
Geezer pro stock G Joined: Jan 2003 Posts: 1,402 Littleton Colo	Try:http://www.winbergcrankshafts.com/cranks/mopar.shtml

Re: SB stroker options for track car [Re: Ron Silva] #432212 08/09/09 02:38 PM 08/09/09 02:38 PM
Joined: Jan 2003 Posts: 5,484 SoCal Brian Hafliger master
Brian Hafliger master Joined: Jan 2003 Posts: 5,484 SoCal	Quote: http://www.ohiocrank.com/mopar_cranks.html Watch the scat cast cranks, because the back flange could be machined too far back. I have heard from several different places about this and problems arising from it. AND: the crank in my 406 Crate wiped out the thrust bearing/flange because of this. You end up with insfficient "converter pull up" and when the engine runs and is warming up and things start to expand it binds up and the problems start. I belive the crank in this Crate motor is a scat cast crank. Yeah I should have elaborated...that was the 4340 Scat crank. So far I've had zero problems with them. Brian Hafliger

Re: SB stroker options for track car [Re: AndyF] #432213 08/09/09 04:29 PM 08/09/09 04:29 PM
Joined: Oct 2003 Posts: 11,684 W. Kentucky justinp61 I Live Here
justinp61 I Live Here Joined: Oct 2003 Posts: 11,684 W. Kentucky	Andy, the forged 4" K-1 crank in my 360 has 2.10" chevy journals. I'm running 6.125 Comp Star rods, Diamond shelf pistons with a .927" pin.

Re: SB stroker options for track car [Re: justinp61] #432214 08/09/09 05:22 PM 08/09/09 05:22 PM
Joined: Jan 2003 Posts: 30,992 Oregon A AndyF OP I Win
AndyF OP I Win A Joined: Jan 2003 Posts: 30,992 Oregon	Quote: Andy, the forged 4" K-1 crank in my 360 has 2.10" chevy journals. I'm running 6.125 Comp Star rods, Diamond shelf pistons with a .927" pin. Cool, that is exactly what I'm looking for. I had forgot about K-1. That is precisely the combo I was thinking about. Justin, did you keep a record of what the bobweight was? Did that K-1 crank balance internally? Last edited by AndyF; 08/09/09 05:35 PM.

Re: SB stroker options for track car [Re: Brian Hafliger] #432215 08/09/09 05:37 PM 08/09/09 05:37 PM
Joined: Jan 2003 Posts: 30,992 Oregon A AndyF OP I Win
AndyF OP I Win A Joined: Jan 2003 Posts: 30,992 Oregon	Quote: I would use a Scat 4" crank, 360 mains if your sticking with the stock block. Your not saving a ton with chevy rods and pins IMO. What kind of cam (FT or roller or hyd roller)are you planning? RPM? Any rules? I love building road race and circle track engines...they are a nice challenge and fun to watch go around the track. Still waiting for my book Andy LOL!! Book is in the mail. This track motor is for the second book. I'd use the SCAT forged crank in a heartbeat if it had the Chevy pins on it. Last time I talked to Tom at SCAT he wasn't too interested in putting Chevy pins on their cranks for some reason. I tried to explain the benefits but his mind seemed to be made up. I could call him back and try again I suppose.

Re: SB stroker options for track car [Re: AndyF] #432216 08/09/09 05:47 PM 08/09/09 05:47 PM
Joined: Oct 2003 Posts: 11,684 W. Kentucky justinp61 I Live Here
justinp61 I Live Here Joined: Oct 2003 Posts: 11,684 W. Kentucky	Quote: Quote: Andy, the forged 4" K-1 crank in my 360 has 2.10" chevy journals. I'm running 6.125 Comp Star rods, Diamond shelf pistons with a .927" pin. Cool, that is exactly what I'm looking for. I had forgot about K-1. That is precisely the combo I was thinking about. Justin, did you keep a record of what the bobweight was? Did that K-1 crank balance internally? Andy, sorry I honestly don't recall the bob weight, I'll check my reciepts to see if it's on one of them. It balanced internal with no mallory, actually there are several holes drilled in it . The rotating assembly came from Dram, he could probably give you a good idea of the bob weight.

Re: SB stroker options for track car [Re: AndyF] #432217 08/09/09 05:53 PM 08/09/09 05:53 PM
Joined: Nov 2004 Posts: 3,544 Syracuse,NY CompWedgeEngines master
CompWedgeEngines master Joined: Nov 2004 Posts: 3,544 Syracuse,NY	I believe your ok now with the current K1's. The early batches of the 360/2.100 cranks were a little light on the counterweights and some combos did need mallory. I think that has been addressed and corrected. They should have them in stock. What you want is a : 360-4000FB6F I have usde and sold a fair amount of K1's and also like the Scats very much, but they just dont seem to want to listen on the 2.200 and 2.100 rod pins. They are REALLY missing the boat. I know several people have approached them on it, and they just dont get it. RIP Monte Smith Your work is a reflection of yourself, autograph it with quality. WD for Diamond Pistons,Sidewinder cylinder heads, Wiseco, K1 rods and cranks,BAM lifters, Morel lifters, Molnar Technologies, Harland Sharp, Pro Gear, Cometic, King Engine Bearings and many others.

Re: SB stroker options for track car [Re: CompWedgeEngines] #432218 08/09/09 06:09 PM 08/09/09 06:09 PM
Joined: Jan 2003 Posts: 30,992 Oregon A AndyF OP I Win
AndyF OP I Win A Joined: Jan 2003 Posts: 30,992 Oregon	Thanks for the part number, I'll run that down. Personally I don't see any reason for anyone to ever build another engine with Mopar rods in it, SB or BB. Just use the BBC or SBC rods for everything. The rods are less expensive, have more options and styles available, and the bearing choice is much larger. I personally don't understand why the crank mfgs don't see it that way but for some reason they don't. Callies has switched almost everything over to the Chevy pins but some vendors stick with the Mopar clubs for some reason.

Re: SB stroker options for track car [Re: AndyF] #432219 08/09/09 07:46 PM 08/09/09 07:46 PM
Joined: Apr 2005 Posts: 1,880 USA Ron Silva top fuel
Ron Silva top fuel Joined: Apr 2005 Posts: 1,880 USA	If they won't give you chevy pins I would just go down the road. I have not run a Mopar rod in probably over 15 years. I put chevy rods in my first stroker motor before they were even very popular, and every one since. 5406752-Demon.JPG (411 downloads) SRT DEMON ONE SEAT

Re: SB stroker options for track car [Re: Ron Silva] #432220 08/09/09 09:30 PM 08/09/09 09:30 PM
Joined: Jan 2003 Posts: 30,992 Oregon A AndyF OP I Win
AndyF OP I Win A Joined: Jan 2003 Posts: 30,992 Oregon	The one reason I'll give SCAT another try is because they have a lightweight option on their crankshaft that takes about 10 lbs off the nose of the car. If I could just get the lightweight crank with 2.100 pins then all would be cool but that option doesn't seem to exist in any of the catalogs I have.

Re: SB stroker options for track car [Re: AndyF] #432221 08/09/09 09:47 PM 08/09/09 09:47 PM
Joined: Jan 2003 Posts: 9,871 Weddington, N.C. Streetwize master
Streetwize master Joined: Jan 2003 Posts: 9,871 Weddington, N.C.	For road racing I think I'd be tempted to run the 3.79 stroke crank with a longer 6.25" rod to keep the side loading down and with a solid cam you'll probably make very close to the same top end power with the same compression and cam. You should wind up with close the same CH and weight piston as a 4" stroke with a 6.125 rod but your rod ratio and piston speed will be more favorable for SUSTAINED High RPM use. You can have too much torque coming off a corner and the compression braking might be a bit less herky jerky with less cubes. I know this from my experience with Cobra replicas that most guys prefer the 3.85 stoke 393" motors with longer rods that keep the side loading down and a wider more tractible powerband with less likelyhood of an overrev....not so much an issue with drag racing but the way oil moves around in a road race car is quite a bit different. Also I'd run the 340 block with it's smaller mains, Canton makes some pretty good road race pans. so a 395" (4.07 x 3.79) would be the way I'd look at going with a Tremec 5 speed, I think you'd make as much power as a 416 with more of a rev cushion up high. WIZE World's Quickest Diahatsu Rocky (??) 414" Stroker Small block Mopar Powered. 10.84 @ 123...and gettin' quicker! https://www.youtube.com/watch?v=-mWzLma3YGI In Car: https://www.youtube.com/watch?v=PjXcf95e6v0

Re: SB stroker options for track car [Re: AndyF] #432222 08/10/09 12:00 AM 08/10/09 12:00 AM
Joined: Jan 2003 Posts: 5,484 SoCal Brian Hafliger master
Brian Hafliger master Joined: Jan 2003 Posts: 5,484 SoCal	Quote: Quote: I would use a Scat 4" crank, 360 mains if your sticking with the stock block. Your not saving a ton with chevy rods and pins IMO. What kind of cam (FT or roller or hyd roller)are you planning? RPM? Any rules? I love building road race and circle track engines...they are a nice challenge and fun to watch go around the track. Still waiting for my book Andy LOL!! Book is in the mail. This track motor is for the second book. I'd use the SCAT forged crank in a heartbeat if it had the Chevy pins on it. Last time I talked to Tom at SCAT he wasn't too interested in putting Chevy pins on their cranks for some reason. I tried to explain the benefits but his mind seemed to be made up. I could call him back and try again I suppose. There just isn't any really huge bene from the chevy stuff. Just go with that crank, I beam rods and a nice lightweight piston and your done. There is some HP in ring pack and bore finish, and even skirt design. I think it would be cool to do a magnum type build with edelbrocks mag head. JMO...LOL! Oh, and I can't wait to read the book!! I owe you twice now...

Re: SB stroker options for track car [Re: Brian Hafliger] #432223 08/10/09 10:58 PM 08/10/09 10:58 PM
Joined: Jan 2003 Posts: 30,992 Oregon A AndyF OP I Win
AndyF OP I Win A Joined: Jan 2003 Posts: 30,992 Oregon	I might try a slightly longer rod such as a Chevy 6.250 for example. It looks to me like there is still plenty of room for the ring pack even with a 4.0 stroke. I need to hear back from a few folks before I make a decision. If I can line up a 340 block from Mopar Performance then we'll go that way. Might even go with a 4.125 bore or larger depending on rings. 4.125 x 4.00 makes a 428 inch SB which should make that A body car scoot around the track.

Re: SB stroker options for track car [Re: AndyF] #432224 08/28/09 12:58 PM 08/28/09 12:58 PM
Joined: Jan 2003 Posts: 30,992 Oregon A AndyF OP I Win
AndyF OP I Win A Joined: Jan 2003 Posts: 30,992 Oregon	I just came across another option which is interesting. Hughes Engines has a special kit made for them which makes a 426 inch motor in a 360 block. They have a crank with 360 mains but 4.180 stroke. There crank uses a small rod pin, Quad 4 I think. They say it installs with very little grinding due to the smaller rod pins. The pistons are setup for pump gas with the CR about 9.75:1 with Edelbrock heads.

Re: SB stroker options for track car [Re: AndyF] #432225 08/28/09 01:35 PM 08/28/09 01:35 PM
Joined: Oct 2008 Posts: 458 Michigan BPE mopar
BPE mopar Joined: Oct 2008 Posts: 458 Michigan	How about a 4.125" stroke with a 6.200" sj chevy rod aroud 1.310 CH. With that piston it will still use a standrd ring pack, and I just happen to have the last of the prototypes in a 360 main. 5446666-4.125Crank.jpg (436 downloads)

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