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What would you limit this short block to? #1547307 12/14/13 03:15 AM 12/14/13 03:15 AM
Joined: Aug 2006 Posts: 2,141 junction city oregon V viperblue72 OP top fuel
viperblue72 OP top fuel V Joined: Aug 2006 Posts: 2,141 junction city oregon	440 .030 with torque plates trw six pack replacement pistons rpm I beam rods with 7/16 arp bolts arp main bolts 440 source heads- not ported yet. Hv oil pump with deep pan 3/8 pickup. So my question is, where would you guys draw the line for limiting horsepower and rpm, head porting, cam size etc. If it was yours how would you build it?

Re: What would you limit this short block to? [Re: viperblue72] #1547308 12/14/13 05:07 AM 12/14/13 05:07 AM
Joined: Aug 2003 Posts: 43,213 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,213 Bend,OR USA	Is it going to be a race motor or a pump gas street and strip motor? If pump gas combo motor I would shoot for a cam and valve train that will make peak power(HP)at or close to 6000 RPM and open the heads up as much as you can afford If it will be a race gas motor go as big as you can on the heads(M.W. size, intake to match and a big CFM carb.) and the cam and valve train Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: What would you limit this short block to? [Re: viperblue72] #1547309 12/14/13 07:42 AM 12/14/13 07:42 AM
Joined: Sep 2013 Posts: 168 Moparts S SSDart member
SSDart member S Joined: Sep 2013 Posts: 168 Moparts	Are these pistons not for a pressed fit rod? Without a doubt the limit is the piston... too heavy and a crappy ring package....

Re: What would you limit this short block to? [Re: SSDart] #1547310 12/14/13 07:49 AM 12/14/13 07:49 AM
Joined: Aug 2006 Posts: 2,141 junction city oregon V viperblue72 OP top fuel
viperblue72 OP top fuel V Joined: Aug 2006 Posts: 2,141 junction city oregon	Yes, street/strip. 10.5 to 1. I know the pistons are heavy, but they are what I have to work with.

Re: What would you limit this short block to? [Re: viperblue72] #1547311 12/14/13 01:30 PM 12/14/13 01:30 PM
Joined: Jan 2003 Posts: 10,010 Frostbitefalls MN (Rocky&Bullw... gregsdart I Live Here
gregsdart I Live Here Joined: Jan 2003 Posts: 10,010 Frostbitefalls MN (Rocky&Bullw...	Quote: Yes, street/strip. 10.5 to 1. I know the pistons are heavy, but they are what I have to work with. As said before, the rings are much thicker than what they need to be. This causes two problems. The ring drag is very high, and costs a lot of power. Also, that extra ring drag really wears on the cylinder walls, shortening the life of the motor. If it were me, I would do what I had to to sell the TRWs and buy some newer lighter forged pistons with narrow ( 1/16 or less) rings. If you really want to stick with the TRWs, then stay at or below about 6000/6200 rpm. Cams as wild as a 590 mopar will make good power shifting at 6,000 to 6200 rpm with the stock port window. If this is a street motor more than strip, I would use a performer RPM and either an 800 or 850 Holley for the most hp. I would not go with a single plane intake unless the launch rpm was at least 4500 plus. If you go with a milder cam, 750 cfm. A 1 7/8 or 2 inch header, with long (40 or more) primarys is best. A collector length of 24 inch would be a good starting point. Last edited by gregsdart; 12/14/13 09:51 PM. 8..603 156 mph best, 2905 lbs 549, indy 572-13, alky

Re: What would you limit this short block to? [Re: viperblue72] #1547312 12/14/13 03:29 PM 12/14/13 03:29 PM
Joined: Sep 2013 Posts: 168 Moparts S SSDart member
SSDart member S Joined: Sep 2013 Posts: 168 Moparts	Quote: Yes, street/strip. 10.5 to 1. I know the pistons are heavy, but they are what I have to work with. Are the RPM rods press fit? or floating??.........not sure how this is going to work..... If you are going to run the TRW piston then keep the RPM reasonable (6000) possible options. -get the pistons lightened -back cut the rings - or use spacers and a narrower ring...... options to

Re: What would you limit this short block to? [Re: viperblue72] #1547313 12/14/13 03:41 PM 12/14/13 03:41 PM
Joined: Aug 2003 Posts: 43,213 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,213 Bend,OR USA	Quote: Yes, street/strip. 10.5 to 1. I know the pistons are heavy, but they are what I have to work with. The last pump gas 9.25 to 1 comp. ratio 440 motor with iron heads with those pistons and LY rods ran high 11s and low 12s in my Duster with a single Holley 850 D.P. It had a Comp Cams small hydraulic shelf cam in it, not tiny but not real big either. I did another 440 with a 3.90 offset ground stock steel crank with aftermarket H beam 7.1 long rods and custom pistons with the Comp Cams XE295 HL cam and a set of unported Eddy RPM with a sixpak setup, that one ran low 11s and high 10s in my Duster on pump gas Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: What would you limit this short block to? [Re: Cab_Burge] #1547314 12/15/13 12:23 AM 12/15/13 12:23 AM
Joined: Aug 2006 Posts: 2,141 junction city oregon V viperblue72 OP top fuel
viperblue72 OP top fuel V Joined: Aug 2006 Posts: 2,141 junction city oregon	Ok, you guys have me convinced to sell the pistons. My first choice will bea Ross flat top since they are light and have 1/16 ring pack.

Re: What would you limit this short block to? [Re: viperblue72] #1547315 12/15/13 12:36 AM 12/15/13 12:36 AM
Joined: Aug 2011 Posts: 188 Middletown, Ohio J Joes66dart member
Joes66dart member J Joined: Aug 2011 Posts: 188 Middletown, Ohio	We run a 40 over 440 with those same heavy trw pistons. It has a stock crank and stock rods. It has a 590 purple shaft in it, stage vi heads. The car ran low 10's with that setup. With a set of stock 915 heads it ran 10.80. Its in a 1966 dart. Evryone says those pistons are to old or to heavy but they work.

Re: What would you limit this short block to? [Re: Joes66dart] #1547316 12/15/13 05:12 AM 12/15/13 05:12 AM
Joined: Aug 2006 Posts: 2,141 junction city oregon V viperblue72 OP top fuel
viperblue72 OP top fuel V Joined: Aug 2006 Posts: 2,141 junction city oregon	I would also feel better about different pistons at this point. I am just being impatient. Ok let's see if I can come up with a plan. 10.5 ross flat top pistons rpm rods source heads, get them ported, rpm intake, Solid lifter cam 255ish@050 ground on 108 isky rockers holley 950. 1 7/8 unknown headers. I have all of these parts except the camshaft and pistons. Ill plan on a 3800ish stall 4.10 dana 295/65 drag radials 3500 pound cuda. Sound good?

Re: What would you limit this short block to? [Re: viperblue72] #1547317 12/15/13 09:19 AM 12/15/13 09:19 AM
Joined: Sep 2013 Posts: 168 Moparts S SSDart member
SSDart member S Joined: Sep 2013 Posts: 168 Moparts	Quote: I would also feel better about different pistons at this point. I am just being impatient. Ok let's see if I can come up with a plan. 10.5 ross flat top pistons rpm rods source heads, get them ported, rpm intake, Solid lifter cam [Email]255ish@050[/Email] ground on 108 isky rockers holley 950. 1 7/8 unknown headers. I have all of these parts except the camshaft and pistons. Ill plan on a 3800ish stall 4.10 dana 295/65 drag radials 3500 pound cuda. Sound good? I would go 245 255 110 on the cam straight up... yes sounds good

Re: What would you limit this short block to? [Re: SSDart] #1547318 12/15/13 09:42 PM 12/15/13 09:42 PM
Joined: Aug 2003 Posts: 43,213 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,213 Bend,OR USA	The 108 LSA cam installed at 103 to 105 on the ILC will give you more bottom end than the same cam ground on with the same lobes grond 110 LSA installed similar If you wanted more top end power then the 110 is the way to go, seeing as the first foot of the trip takes the longest time incrementily to move then the bottom end is more important, hence my preferences to using cams with 106 to 108 LSA on pump gas motors that will make peak HP and torque under 7000 RPM Know what YOU want the build to do and then buy the parts to get the results YOU want Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: What would you limit this short block to? [Re: Cab_Burge] #1547319 12/16/13 02:00 AM 12/16/13 02:00 AM
Joined: Sep 2013 Posts: 168 Moparts S SSDart member
SSDart member S Joined: Sep 2013 Posts: 168 Moparts	Quote: The 108 LSA cam installed at 103 to 105 on the ILC will give you more bottom end than the same cam ground on with the same lobes grond 110 LSA installed similar If you wanted more top end power then the 110 is the way to go, seeing as the first foot of the trip takes the longest time incrementily to move then the bottom end is more important, hence my preferences to using cams with 106 to 108 LSA on pump gas motors that will make peak HP and torque under 7000 RPM Know what YOU want the build to do and then buy the parts to get the results YOU want May I ask why you feel you need to retard the exhaust? You don't suggest any cam specs beside lca and lsa these alone do not make a cam....... If you spec it right in the first place,you do not need to advance it........ Last edited by SSDart; 12/16/13 02:09 AM.

Re: What would you limit this short block to? [Re: SSDart] #1547320 12/16/13 02:38 AM 12/16/13 02:38 AM
Joined: Aug 2003 Posts: 43,213 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,213 Bend,OR USA	My reasoning on the closer lobe centers and advancing the opening of both the intake and exhaust is based on years of drag racing and engine dyno tests on N/A Mopar V8 with stock type heads where we have tried different lobe centers with the same lobes on different cams and then advanced and retarded those same cams on the dyno. A fellow long time Mopar stock and SS racer told me years ago to focus on the first hundred feet of the 1/4 mile for the best results I found out along the way, sometimes the hardway, he was correct The production heads on the Mopar V8 BB and SB motors limit how much air the motor will see at WOT, once they have reach max flow it is time to shift the tranny to get the motor back under the peak HP RPM(curve), what I have seen is most of those type motors like to be shifted between 5500 and 6400 RPM When a freind of mines (and good customer) NHRA legal record holding 1970 SB E body Challenger can run 1.34 60 ft. times with a NHRA legal cam with 105 LSA in at 101 I think the results speak for themselves You have to know I have not had a lot of expereince with Mopar V8 BB that have had really good heads, only one so far that has a set of Indy 440-1 that are CNC ported, that motor made 1.61 HP per C.I. not a really good result It does have a cam ground on 110 LSA installed at 108 ATDC on the intake lobes due to the converter being a 5500 RPM stall in a 3000 lb car with the driver, no track results yet Enough said on that subject, you do it your way and I'll do it my way Sorry for the hijack Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: What would you limit this short block to? [Re: Cab_Burge] #1547321 12/16/13 03:05 PM 12/16/13 03:05 PM
Joined: Sep 2013 Posts: 168 Moparts S SSDart member
SSDart member S Joined: Sep 2013 Posts: 168 Moparts	To the OP I still feel/know that cam will work well. You can not go off of lsa's and lca's alone when comparing cams. CI/per hp numbers are also tainted for comparison, when there are still no duration specs...... now that said, the fastest way to accelerate a car is to have as much power available upon shift recovery/launch rpm. Peak hp does not accelerate your car....... Also to the OP. I once inherited the task of re-doing an engine in a combo very similar to yours... this car was a bit heavier and had stock ported heads. We went from a .509 mp cam to a 235/245 iirc ground on 110..... This car was day and night in power. He could not get his head around putting a smaller cam into this engine and really fought me on it............ Man is he ever sold on it now...... Last edited by SSDart; 12/16/13 03:17 PM.

Re: What would you limit this short block to? [Re: SSDart] #1547322 12/16/13 04:55 PM 12/16/13 04:55 PM
Joined: Aug 2003 Posts: 43,213 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,213 Bend,OR USA	I hate most of the Mopar cams Going to a modern grind from one of the old Mopar grinds will normally make more power than the older Mopar grinds do I found that out a long time ago As far as speccing a cam over the internet without knowing the rear gear ratio, tire circumference, torque converter size and stall, the customers preference for driving charastics and thier prefer RPM operating range is a fools folly as far as I am concerned the choice of LSA and where to install them is based on personel expereinces with more than one motor and one customer Why do you think most of the aftermarket cams sold today for BB Mopars are sent out with 4 degrees advance built into to them, regardless of the lobe type, flat lifter and roller lobes Trying things, testing, will give you a larger data base to make your future choices on Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: What would you limit this short block to? [Re: Cab_Burge] #1547323 12/16/13 06:07 PM 12/16/13 06:07 PM
Joined: Sep 2013 Posts: 168 Moparts S SSDart member
SSDart member S Joined: Sep 2013 Posts: 168 Moparts	Quote: I hate most of the Mopar cams Going to a modern grind from one of the old Mopar grinds will normally make more power than the older Mopar grinds do This grind was less aggressive then the old mopar grind, the old mopar grinds were ground as single pattern cams to save on cost due to the fact they were grinding cams in that day off of masters which took time in setting up and increased cost. Quote: Why do you think most of the aftermarket cams sold today for BB Mopars are sent out with 4 degrees advance built into to them, regardless of the lobe type, flat lifter and roller lobes Trying things, testing, will give you a larger data base to make your future choices on This is very simple....... The cams especially off the shelf of today are market driven grinds. Most people will call a few cam companies for a recommendation... 1 knowing that most people will buy pretty much the biggest cam recommended to them, they need to recommend a cam too big to make the sale.... advancing it 4 degrees helps the too big of cam perform better 2 now that everyone is grinding there cams with 4 degrees advance..... it is now the "hot ticket".. if your cam is not ground 4 deg advanced you will not sell a cam......... Starting out with a cam that is straight up, then testing buy advancing and or retarding does give you the best results.... Tell me this...... with your experience..... how much does a 4inch stroke SB engine change in lsa over a 3.58 or 3.31...... there must be a huge difference the 4inch stroke has the rod ratio of a 350 chevy......... Or do all mopars need the same lsa? If you cannot recommend a complete grind without knowing all the details? Then how can you recommend a lsa ? Does the exhaust not effect the lsa? Try restricting the exhaust on a tighter lsa and see how well that works........ I'm really not trying to get into a debate with you....... I suggested a cam from my own personal experience.... you are picking my suggestion apart and not contributing any info of value....... you cannot pick a cam on LSA alone. it is impossible, and the lsa is still effected by your choice in lobes.. it is a full circle deal......... The OP can put in a cam with 108 lsa because a 105lsa set the world on fire with your buddies stocker, for all I care... His choice... I'm not here to sell anything........

Re: What would you limit this short block to? [Re: SSDart] #1547324 12/18/13 03:42 AM 12/18/13 03:42 AM
Joined: Aug 2006 Posts: 2,141 junction city oregon V viperblue72 OP top fuel
viperblue72 OP top fuel V Joined: Aug 2006 Posts: 2,141 junction city oregon	I think Cab, won't give complete specs, because his info is in general. In general most 440 users with stock ports, have had good results with what Cab is saying. I only know this because I ask a lot of questions at the drag strip. Is bigger better? Not always, but it's also tough to over cam a 440 with stock ports, unless it's a street car. And there is also diminishing returns going bigger. I know there isn't going to be a magic camshaft, and most of it is going to come down to preference. I asked for opinions and some are gonna be different than others. That's okay. . When the time comes to choose the camshaft, I will call bullet, and go with what they recommend. Thank you for the advice.

Re: What would you limit this short block to? [Re: viperblue72] #1547325 12/20/13 09:56 PM 12/20/13 09:56 PM
Joined: Jan 2003 Posts: 5,762 Hot Rod Ridge FastmOp master
FastmOp master Joined: Jan 2003 Posts: 5,762 Hot Rod Ridge	I would just leave the second ring off the TRWs. Stick a Herbert cam kit in it and run it.

Re: What would you limit this short block to? [Re: viperblue72] #1547326 12/20/13 11:12 PM 12/20/13 11:12 PM
Joined: Jul 2004 Posts: 19,317 State of confusion T Thumperdart I Live Here
Thumperdart I Live Here T Joined: Jul 2004 Posts: 19,317 State of confusion	Quote: Ok, you guys have me convinced to sell the pistons. My first choice will bea Ross flat top since they are light and have 1/16 ring pack. If you`re going to port the heads I`d put a cam in the has lift slightly above the heads peak numbers and if you have exhaust maybe a 108 lsa installed at 104-105 w/duration at .050 between 250-260 or more if you`re brave. I run Isky stuff myself and had em grind my roller w/.680-.660 lift and 275-280 @ .050 on a 108 lsa installed at 104-105 to compensate for the less than desireable ex. port on the rpm heads.............good luck. 72 Dart 470 n/a BB stroker street car `THUMPER`...Check me out on FB Dominic Thumper for videos and lots of carb pics......760-900-3895.....

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