View Full Version : Capabilities Of A Btm
09-24-2003, 08:52 PM
i know that a btm can retard between 1 and 3 deg. of timing per pound of boost up to 20 deg. total, which sounds all well and good but..........
a local speed shop owner told me that it only works for the first 5 psi.
so it can pull out 20 deg. but at only 5 psi that would make the car fall on its face at low boost pressures, or it could run well at the low end, but then have a flat timing curve up top
i would rather it be able to pull out (for example) 1 deg. per pound up to 20 psi. at least it would still have a good timing curve
is this correct ?
what good would 20 deg. at 5psi do for a car that runs 15 psi. ??? NONE
you would be better off with a chip to take care of the timing
09-24-2003, 10:12 PM
The control knob on the MSD Boost Timing Masters (BTM) is a variable potentiometer, so the adjustment range is actually from 0 to 3 degrees per pound of boost. If you have the knob set at 0.5 degree then the timing would be retarded 0.5 degree at 1 pound of boost, 1 at 2, 1.5 at 3, 2 at 4, 2.5 at 5, 3 at 6 and so on until you hit 20 degrees. I am not sure which BTM you where refering to, but on some of the models such as the PN 5462, 8762, and 8962 you can also set the boost point where you want the timing to start retarding at. Some engines can handle full timing at low boost levels and therefore you can know set the retard to strat backing the timing down at say 4 pounds of boost. This is nice because it maintains a quick throttle responce at low speed.
09-26-2003, 06:04 PM
so, it's no true that it will only work up to 5 psi ?
i already have a digital 6 what would be the part # i need for a btm that would add on to that. one wit all the bells and whistles like your talking about.
all i'm looking for is 1 deg. per pound up to 15psi.
i was told by several people that the btm just wont do that.
09-26-2003, 08:49 PM
The MSD Boost Timing Master (BTM) that you need for your MSD Digital 6 is PN 8762. Her are the installation instructions for that unit and also some additional info on it. I think that whoever was telling you that it would only retard up to 5 psi was getting it mixed up with the start point where the retard begins at. You can set it so that it will not start retarding from 0-5psi. See the bottom of page two in the installation instructions.
10-02-2003, 07:53 PM
ok i went to my local speed shop and picked up this btm
everything looked good, until i read the directions.
its says that the max. amount of timing that can be removed is15 deg.
both you and the ad for this product stated a max of 20 deg
whats the deal
10-07-2003, 06:29 AM
whats the story ?
why does all the info on this product say a max of 20 and now that i went and bought it i see it says a max of 15.
i could really use the extra 5 deg.
10-08-2003, 03:36 PM
We apologize for the confusion on this. I spoke with the engineer that designed the BTM's and the units will pull out 20 degrees. This change was made approximately 1 year ago, so anything currently purchased will be 20 degrees.
10-10-2003, 10:47 AM
There has been some major confusion on this. We were in the process of getting the instructions changed and up on double checking the numbers it is 15 degrees not 20. The transducer or pressure sensor in the unit is rated to 20 psi. I apologize for the misunderstanding on this. I do also have a question about the Ad you saw the 20 degrees description in? Was in a magazine, on the web??
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