Quinc
Buy a Superjet
- Location
- California
Has anyone else heard of the stock cdis having different curves? I have only read about them having different rpm limits.
Msd enhancer vs protec modded cdi
- Thread starter Laxpro2
- Start date
OCD Solutions
Original, Clean and Dependable Solutions
- Location
- Rentz, GA
I always thought the same thing and have represented them as identical for years.
I'm working on some answers now...I'll say this, I am already shocked at the results after just doing a 62T vs 61X.
On a side note, hooking the drive motor up to my CNC controller was a stroke of genius! It took me seconds to map out an incremental program to step through all the different RPM's for testing.
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OCD Solutions
Original, Clean and Dependable Solutions
- Location
- Rentz, GA
Well here is the data*...I did the hard part, now somebody with more time than I can type it into a graph. 
* I make no claim to it's accuracy as my test bench does not have a TDC to zero out my timing. The curve will be accurate but the whole thing may shift up or down according to how far off of true "zero" timing I really am. (Updated with corrected values to reflect a 2.5deg correction to baseline)
I would like to think I am within a half degree of accuracy but I did not see the 16deg of retard that TNT referenced so I am questioning my results.
***Updated image to reflect true zero/TDC***
* I make no claim to it's accuracy as my test bench does not have a TDC to zero out my timing. The curve will be accurate but the whole thing may shift up or down according to how far off of true "zero" timing I really am. (Updated with corrected values to reflect a 2.5deg correction to baseline)
I would like to think I am within a half degree of accuracy but I did not see the 16deg of retard that TNT referenced so I am questioning my results.
***Updated image to reflect true zero/TDC***
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- Location
- North Carolina
@OCD Solutions. Don't you have an epic there you could try too? With a known curve.... just to be sure it didn't show flat too.
OCD Solutions
Original, Clean and Dependable Solutions
- Location
- Rentz, GA
I can set an epic to zero and it will flatline within half a degree of my indicated zero.
- Location
- North Carolina
I always told myself I would never spend money on another enhancer. This just backs up my decision. I'm curious to see/try the new advent for the superjet. Has a new billet cdi case that is serviceable. My total loss is working so I'm good for a while.
OCD Solutions
Original, Clean and Dependable Solutions
- Location
- Rentz, GA
Didn't Jetinetics release a new system recently?
Duonetics?
I was told about it but I have yet to see or hear about anyone running it yet.
Duonetics?
I was told about it but I have yet to see or hear about anyone running it yet.
I will buy the one OCD tested. Someone send him another one so we can see how much they vary!
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OCD Solutions
Original, Clean and Dependable Solutions
- Location
- Rentz, GA
I have a couple more here I could test, I just didn't have the time tonight.
@OCD Solutions great work
That msd is way hot. Doesn't match what they say and a few years ago what you posted an MSD curve in a epic Was that what you measured or just Put in from msd paperwork? Again that msd is melt down zone territoryWell here is the data*...I did the hard part, now somebody with more time than I can type it into a graph.
* I make no claim to it's accuracy as my test bench does not have a TDC to zero out my timing. The curve will be accurate but the whole thing may shift up or down according to how far off of true "zero" timing I really am.
I would like to think I am within a half degree of accuracy but I did not see the 16deg of retard that TNT referenced so I am questioning my results.
View attachment 336007
Again wow on the msd
OCD Solutions
Original, Clean and Dependable Solutions
- Location
- Rentz, GA
Hence the disclaimer on accuracy. 
It could be a calibration issue. Subtract 4 deg from every reading and things fall inline pretty close to my expectations and would also reflect more along the lines of what TNT was saying too.
When I first set up my Epic curves, I had just copied the curve from published MSD information and punched it into the ATP software. I hadn't even built my test bench at that point.
I half ass mapped them back in the beginning but didn't have it setup anywhere close to what I have now so it was a good exercise to go back and revisit this.
Since adding a VFD under CNC control, I can punch in an RPM anywhere from 100 to 11,000 RPM and be within 25 RPM of target. It makes things much easier, far more accurate and repeatable.
It just doesn't solve the one detail that has always plagued my test bench, and that is establishing a true zero. When playing with the JSTL system, it was off by about 4 deg as well. I indexed the crank and each flywheel in an assembled engine but it was still out. Possibly the difference between mechanical zero and magnetic "slip".
It could be a calibration issue. Subtract 4 deg from every reading and things fall inline pretty close to my expectations and would also reflect more along the lines of what TNT was saying too.
When I first set up my Epic curves, I had just copied the curve from published MSD information and punched it into the ATP software. I hadn't even built my test bench at that point.
I half ass mapped them back in the beginning but didn't have it setup anywhere close to what I have now so it was a good exercise to go back and revisit this.
Since adding a VFD under CNC control, I can punch in an RPM anywhere from 100 to 11,000 RPM and be within 25 RPM of target. It makes things much easier, far more accurate and repeatable.
It just doesn't solve the one detail that has always plagued my test bench, and that is establishing a true zero. When playing with the JSTL system, it was off by about 4 deg as well. I indexed the crank and each flywheel in an assembled engine but it was still out. Possibly the difference between mechanical zero and magnetic "slip".
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OCD Solutions
Original, Clean and Dependable Solutions
- Location
- Rentz, GA
If I apply an offset correction of -1.5 deg to all the values, it improves some areas but not others so that's not the answer either.
I will need to run the tests again but start with an epic that I can program to zero and establish/verify a baseline. Then run multiples of each CDI to see how much is variance vs measurement error.
I will need to run the tests again but start with an epic that I can program to zero and establish/verify a baseline. Then run multiples of each CDI to see how much is variance vs measurement error.
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tntsuperjet
Tntperformance-engineering.com
- Location
- Georgetown ca
Yes
tntsuperjet
Tntperformance-engineering.com
- Location
- Georgetown ca
OCD, my big worry is you have timing curve at 7500 of 62t box and it should have flat lined on rev limit at 6950 is soft cut 7200 is hard cut
OCD Solutions
Original, Clean and Dependable Solutions
- Location
- Rentz, GA
Sorry Tim, I should have specified. All I currently have here are modded CDI's so all the rev limits are adjustable and turned up beyond the limits of this test.
But, that brings up yet another interesting variable...I was also under the impression that modifying the rev limit had no affect on the timing curve. Maybe it's time to revisit that detail as well and start fresh with unmodified stock CDI's.
That might further explain why the 4.5 deg offset correction worked out for the MSD numbers and not the stockers.
But, that brings up yet another interesting variable...I was also under the impression that modifying the rev limit had no affect on the timing curve. Maybe it's time to revisit that detail as well and start fresh with unmodified stock CDI's.
That might further explain why the 4.5 deg offset correction worked out for the MSD numbers and not the stockers.
waxhead
wannabe backflipper
- Location
- gold coast
Doesn't look that great for the 61x curve does it, pretty much has everything you don't want
Quinc
Buy a Superjet
- Location
- California
Can you show us your results from your test bench?
tntsuperjet
Tntperformance-engineering.com
- Location
- Georgetown ca
Yea the 61x box not good at all.
OCD, you have 70% of the puzzle.
Now you need to build a pressure chamber.
You will be shocked at how you will start hearing spark misfires above 5,000 once you pressurize the chamber with a spark plug in it.
You will instantly find out how important spark plug gap is.
Take an old trashed dome weld a tube to it and put 3/8 thick plexiglass bottom on it so you can still visually see the spark. Using pressure reg slowly raise the pressure in the cylinder at high rpm and once you get over 120psi you see the spark starts to misfire at a .035 gap once you get over 160ish you will only get about 1 spark out of 50 to gap the plug and your timing curve will jump all over the board.
You find that the stock ignition can only fire accuratly above 150psi with .015 plug gap.
OCD, you have 70% of the puzzle.
Now you need to build a pressure chamber.
You will be shocked at how you will start hearing spark misfires above 5,000 once you pressurize the chamber with a spark plug in it.
You will instantly find out how important spark plug gap is.
Take an old trashed dome weld a tube to it and put 3/8 thick plexiglass bottom on it so you can still visually see the spark. Using pressure reg slowly raise the pressure in the cylinder at high rpm and once you get over 120psi you see the spark starts to misfire at a .035 gap once you get over 160ish you will only get about 1 spark out of 50 to gap the plug and your timing curve will jump all over the board.
You find that the stock ignition can only fire accuratly above 150psi with .015 plug gap.
tntsuperjet
Tntperformance-engineering.com
- Location
- Georgetown ca
My pressure chamber is two domes in a 1/2 Lexan tube.
O ring the outer of a dome and slide each dome in from opposite sides and there capped with all threadgoing full length so domes can't slide out of tube.
A friend did the plexi plate and his system cost 10 bucks.
The 1/2 lexan tube was 100 bucks.
O ring the outer of a dome and slide each dome in from opposite sides and there capped with all threadgoing full length so domes can't slide out of tube.
A friend did the plexi plate and his system cost 10 bucks.
The 1/2 lexan tube was 100 bucks.