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Re: Bog when Engine is Warm [Re: cjskotni] #1668002 09/07/14 01:31 PM 09/07/14 01:31 PM
Joined: Sep 2007 Posts: 14,889 up yours Supercuda About to go away
Supercuda About to go away Joined: Sep 2007 Posts: 14,889 up yours	Problem with most dyno tunes is that the tune WOT. Transition and driveability are not addressed other than to make sure it isn't totally horrible. Your best best bet is to install a wideband O2 and data logger to tune it right. Otherwise your sorta guessing what needs to be done. They say there are no such thing as a stupid question. They say there is always the exception that proves the rule. Don't be the exception.

Re: Bog when Engine is Warm [Re: Supercuda] #1668003 09/13/14 04:51 PM 09/13/14 04:51 PM
Joined: Jul 2007 Posts: 1,526 North Carolina cjskotni OP pro stock
cjskotni OP pro stock Joined: Jul 2007 Posts: 1,526 North Carolina	I plan on breaking into this soon when I have some spare time. In the meanwhile, what do you guys run as far as cam/nozzle size on your BB strokers? Mine is a 400>>499 relatively mild as far as cam goes. What size nozzle would you guys 'expect' to see on this kind of motor? I know a lot goes into what it will end up taking but is a 42 'off the charts'? The only thing I have to compare to is my friend's SBC 350 which takes a 32 IIRC but much smaller motor....

Re: Bog when Engine is Warm [Re: cjskotni] #1668004 09/14/14 01:17 AM 09/14/14 01:17 AM
Joined: May 2005 Posts: 598 NC, USA D davenc mopar
davenc mopar D Joined: May 2005 Posts: 598 NC, USA	On a dual-plane manifold, a 042 shooter seems quite large. As others have mentioned, the pink cam may not be the best for a street car since it is lazy in lift right off idle. I would suggest changing the pump cam first, and then come back down on the shooter. Every setup is slightly different. Try an orange cam to start. I suspect the shooter can come down into the range of 031 with the right cam but change one thing at a time. In my opinion, the cam is the more important of the two on a street car.

Re: Bog when Engine is Warm [Re: davenc] #1668005 09/14/14 01:20 PM 09/14/14 01:20 PM
Joined: Jul 2007 Posts: 1,526 North Carolina cjskotni OP pro stock
cjskotni OP pro stock Joined: Jul 2007 Posts: 1,526 North Carolina	Quote: On a dual-plane manifold, a 042 shooter seems quite large. As others have mentioned, the pink cam may not be the best for a street car since it is lazy in lift right off idle. I would suggest changing the pump cam first, and then come back down on the shooter. Every setup is slightly different. Try an orange cam to start. I suspect the shooter can come down into the range of 031 with the right cam but change one thing at a time. In my opinion, the cam is the more important of the two on a street car. FWIW I have the MP single plane manifold, not a dual plane. I played around a little today with the car (more trying to test for vapor lock) but got it good and hot and tried to note this issue. It seems the bog only occurs if the throttle is blipped pretty fast and over 50% or so. Just giving it some moderate pedal or a blip under half throttle seems fine...no bog. If the bog occurs at quick throttle opening over 50%, this means I need a cam that gives more fuel in that range (>50%)? Either way, I will get my buddy's set of cams and try the red or orange and see what happens. I have a 32/38/42 squirters here I can try later if that helps the problem. Thanks so much guys!

Re: Bog when Engine is Warm [Re: cjskotni] #1668006 09/14/14 08:25 PM 09/14/14 08:25 PM
Joined: May 2005 Posts: 598 NC, USA D davenc mopar
davenc mopar D Joined: May 2005 Posts: 598 NC, USA	Was the "blip" with no load on the motor, or while the vehicle is in motion? If it stumbles or bogs with no load, then the setup is farther off. You are correct about perhaps needing more cam lift above half-throttle. Note though that a smaller squirter will extend the duration of the pump shot. I still feel it is best to get the right cam first, and then fine tune with the squirter. The chart you posted is helpful but does not show the effect of the two cam positions. If your motor is fine just off idle, you can try your current cam in the other position so that the lift occurs at higher throttle position degrees.

Re: Bog when Engine is Warm [Re: davenc] #1668007 09/14/14 08:45 PM 09/14/14 08:45 PM
Joined: Jul 2007 Posts: 1,526 North Carolina cjskotni OP pro stock
cjskotni OP pro stock Joined: Jul 2007 Posts: 1,526 North Carolina	Quote: Was the "blip" with no load on the motor, or while the vehicle is in motion? I did the blip with the car rolling and/or at a standstill in gear so under a load. The engine doesn't stumble at all when it's out of gear so not that far off!

Re: Bog when Engine is Warm [Re: cjskotni] #1668008 02/23/15 06:05 PM 02/23/15 06:05 PM
Joined: Jul 2007 Posts: 1,526 North Carolina cjskotni OP pro stock
cjskotni OP pro stock Joined: Jul 2007 Posts: 1,526 North Carolina	Ok guys, I know it's been awhile since I posted this but I finally have the restoration part of the car done so now I have more time to circle back on these little mechanical gremlins. I got the Holley tuning kit and swapped in the red cam (from the pink there) and went to a 37 squirter (from 42). I had to shorten up the accel pump lever adjustment screw a lot...like 7-8 turns to get it where it was just resting on the pump lever with the throttle closed. I did the 15 thousandths feeler gauge as well on open throttle to make sure it didn't over extend the arm and all is good there. Whoa what a difference! I scared myself a time or two when I blipped the throttle. Now I can break the tires loose at 40 mph when I blip it! Of course now I notice that when I have it under WOT for more than 2-3 seconds, it is pinging a little bit so I guess it's time to roll the timing back a degree or two. Man that stroker can pull now! Thanks guys!

Re: Bog when Engine is Warm [Re: cjskotni] #1668009 02/23/15 06:45 PM 02/23/15 06:45 PM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: what a difference! I scared myself a time or two when I blipped the throttle. Now I can break the tires loose at 40 mph when I blip it! Of course now I notice that when I have it under WOT for more than 2-3 seconds, it is pinging a little bit so I guess it's time to roll the timing back a degree or two. Man that stroker can pull now! Thanks guys! You sound pumped! On the timing you might go to a slightly heavier spring for either of the two springs in there (I'm assuming 2 light ones) until the pinging stops under WOT, since if your initial and total are correct as is you would not want to compromise them for the pinging live every 24 hour block of time like it's your last day on earth

Re: Bog when Engine is Warm [Re: RapidRobert] #1668010 03/07/15 05:43 PM 03/07/15 05:43 PM
Joined: Jul 2007 Posts: 1,526 North Carolina cjskotni OP pro stock
cjskotni OP pro stock Joined: Jul 2007 Posts: 1,526 North Carolina	Quote: Quote: what a difference! I scared myself a time or two when I blipped the throttle. Now I can break the tires loose at 40 mph when I blip it! Of course now I notice that when I have it under WOT for more than 2-3 seconds, it is pinging a little bit so I guess it's time to roll the timing back a degree or two. Man that stroker can pull now! Thanks guys! You sound pumped! On the timing you might go to a slightly heavier spring for either of the two springs in there (I'm assuming 2 light ones) until the pinging stops under WOT, since if your initial and total are correct as is you would not want to compromise them for the pinging I measured the total timing which is 36 degrees...so 20 degree advance (16 initial). Do you have a part number and a recommendation as to what springs I need to use to back this down to maybe a 16-18 degree advance? This is the standard MP distributor. Thanks!

Re: Bog when Engine is Warm [Re: cjskotni] #1668011 03/08/15 02:25 AM 03/08/15 02:25 AM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: I measured the total timing which is 36 degrees...so 20 degree advance (16 initial). Do you have a part number and a recommendation as to what springs I need to use to back this down to maybe a 16-18 degree advance? This is the standard MP distributor. Thanks! springs will not change the total only the RPM that the 36 total occurs. A heavier spring or springs makes the 20 deg slope to occur (start/end) at a higher RPM at any point in the slope (& less advance=less pinging). (1) see (& post) what springs are in there now (2) with your dialback & tach note the RPM that the adv stop advancing (that's when the slots are maxed). Here's a chart for a start tho the crane springs mentioned are no longer available but Ace hardware springs work just need to experiment with a slightly heavier one till you get just under the pinging point at WOT up thru the gears & the slope is linear whether you change one or both springs 8453048-advancecurves.jpg (108 downloads) live every 24 hour block of time like it's your last day on earth

Re: Bog when Engine is Warm [Re: RapidRobert] #1668012 03/08/15 12:08 PM 03/08/15 12:08 PM
Joined: Jul 2007 Posts: 1,526 North Carolina cjskotni OP pro stock
cjskotni OP pro stock Joined: Jul 2007 Posts: 1,526 North Carolina	Quote: Quote: I measured the total timing which is 36 degrees...so 20 degree advance (16 initial). Do you have a part number and a recommendation as to what springs I need to use to back this down to maybe a 16-18 degree advance? This is the standard MP distributor. Thanks! springs will not change the total only the RPM that the 36 total occurs. A heavier spring or springs makes the 20 deg slope to occur (start/end) at a higher RPM at any point in the slope (& less advance=less pinging). (1) see (& post) what springs are in there now (2) with your dialback & tach note the RPM that the adv stop advancing (that's when the slots are maxed). Here's a chart for a start tho the crane springs mentioned are no longer available but Ace hardware springs work just need to experiment with a slightly heavier one till you get just under the pinging point at WOT up thru the gears & the slope is linear whether you change one or both springs The advance doesn't stop until the engine is in the 2500 RPM range from what I saw. Wouldn't it be better to shorten the slots to just limit the timing advance? I am not proficient with a welder so doesn't somebody make a plate that does this? I seem to remember somebody had a plate with various slots to limit the advance to 18/16/etc increments. EDIT: This is what I am talking about. Any ideas? Does it work? Last edited by cjskotni; 03/08/15 12:22 PM.

Re: Bog when Engine is Warm [Re: cjskotni] #1668013 03/08/15 01:49 PM 03/08/15 01:49 PM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: Wouldn't it be better to shorten the slots to just limit the timing advance? Any ideas? Does it work? (1) no (2) of course! (3) yes I hear the FBO plate works OK but 36 total is fine but it coming in too fast. 35 is a tried & true total for a std sb but strokers do have alightly different tiotal requirements but 36 ain't a dealbreaker. I am a fan of experimentation & wouldn't see an issue with trying the plate and or going to a heavier spring & seeing which one of the two works the best for your app. I'm sure the plate is cheap. EDIT Do you have a BB or SB? If BB I would stay at 36 & go to a heavier spring Last edited by RapidRobert; 03/08/15 02:44 PM. live every 24 hour block of time like it's your last day on earth

Re: Bog when Engine is Warm [Re: RapidRobert] #1668014 03/08/15 03:46 PM 03/08/15 03:46 PM
Joined: Jul 2007 Posts: 1,526 North Carolina cjskotni OP pro stock
cjskotni OP pro stock Joined: Jul 2007 Posts: 1,526 North Carolina	It's a B stroker 400>>499.

Re: Bog when Engine is Warm [Re: cjskotni] #1668015 03/08/15 04:12 PM 03/08/15 04:12 PM
Joined: Aug 2003 Posts: 43,116 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,116 Bend,OR USA	Quote: I had to shorten up the accel pump lever adjustment screw a lot...like 7-8 turns to get it where it was just resting on the pump lever with the throttle closed. I did the 15 thousandths feeler gauge as well on open throttle to make sure it didn't over extend the arm and all is good there. Whoa what a difference! I scared myself a time or two when I blipped the throttle. Now I can break the tires loose at 40 mph when I blip it! Of course now I notice that when I have it under WOT for more than 2-3 seconds, it is pinging a little bit so I guess it's time to roll the timing back a degree or two. Man that stroker can pull now! Thanks guys! Two suggestions, try a 32 or 35 squirter next,get the smalest one in it that won't bog with the accelerator pump arm set up properly At the same time back the timing up to 34 degrees total with the motor at or above 4000 RPM Don't change the amount of mechanical advance , just the initial If it still pings try a colder plug by one heat range lower BTW, what brand and heat range, plug number, are you running now? Now that you have opened the door to more power we need to maximise it so you can really get pump up, scare the poop out of you Mopowered Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

Re: Bog when Engine is Warm [Re: Cab_Burge] #1668016 03/08/15 04:22 PM 03/08/15 04:22 PM
Joined: Jul 2007 Posts: 1,526 North Carolina cjskotni OP pro stock
cjskotni OP pro stock Joined: Jul 2007 Posts: 1,526 North Carolina	With the dizzy advancing 20, this would mean only 14 of intial timing. On the dyno, we determined that the engine made the most power with 18* initial but of course pinged when you opened it up. I don't think rolling back to 14* is enough timing? I am running Champion RC12YC. EDIT: I am going to try Autolite 3923 which is one heat step down from these Champions. I am guessing with the 10.4:1 compression this might not be a bad idea. Last edited by cjskotni; 03/08/15 04:49 PM.

Re: Bog when Engine is Warm [Re: cjskotni] #1668017 03/08/15 06:16 PM 03/08/15 06:16 PM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: I am guessing with the 10.4:1 compression this might not be a bad idea. You need more octane, if you build a monster you gotta feed it want it wants (needs). You're timing numbers ain't out of line but your SCR (& therefore DCR) is too high for your (current) choice of fuel. live every 24 hour block of time like it's your last day on earth

Re: Bog when Engine is Warm [Re: RapidRobert] #1668018 03/09/15 08:45 AM 03/09/15 08:45 AM
Joined: Jul 2007 Posts: 1,526 North Carolina cjskotni OP pro stock
cjskotni OP pro stock Joined: Jul 2007 Posts: 1,526 North Carolina	Quote: Quote: I am guessing with the 10.4:1 compression this might not be a bad idea. You need more octane, if you build a monster you gotta feed it want it wants (needs). You're timing numbers ain't out of line but your SCR (& therefore DCR) is too high for your (current) choice of fuel. I realize this number is high but I am running aluminum heads. I know people here have run much higher with pump fuel. BTW I did take it out today with the colder plugs and took it up to WOT for a few seconds...enough to open the the secondaries and I didn't hear any pinging. I will keep testing and maybe try a heavier spring as well...

Re: Bog when Engine is Warm [Re: cjskotni] #1668019 03/09/15 12:48 PM 03/09/15 12:48 PM
Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska R RapidRobert Circle Track
RapidRobert Circle Track R Joined: Nov 2003 Posts: 36,040 Lincoln Nebraska	Quote: BTW I did take it out today with the colder plugs and took it up to WOT for a few seconds...enough to open the the secondaries and I didn't hear any pinging. I will keep testing and maybe try a heavier spring as well... Man I had no idea a colder plug would make that much difference , if it ain't pinging you're set live every 24 hour block of time like it's your last day on earth

Re: Bog when Engine is Warm [Re: cjskotni] #1668020 03/09/15 04:35 PM 03/09/15 04:35 PM
Joined: Aug 2003 Posts: 43,116 Bend,OR USA C Cab_Burge I Win
Cab_Burge I Win C Joined: Aug 2003 Posts: 43,116 Bend,OR USA	Buy a set of Champion RC9YC and try them later Change them squirters also That way it will really smoke them hind tires at speed Mr.Cab Racing and winning with Mopars since 1964. (Old F--t, Huh)

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