 Capacitive Discharge Ignition, Any benifits to using the MSD system? |
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| Driver174 |
 Jul 30 2018, 08:33 PM
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Member  Group: Members Posts: 106 Joined: 2-February 17 From: Nevada Member No.: 20,806 Region Association: None 
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914-4 2L race engine, 10.3:1 compression ratio and twin Weber's
Anyone have experience with the MSD systems on a Type IV? I'm thinking there may be benifits to having the higher spark voltages when compression ratio is relatively high. MSD claims plug gaps of .050 - .060" are possible, and that multiple sparks at lower RPM's improve throttle response. Thus, makes sense, but does anyone have real world experience that support these claims? |
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| HAM Inc |
Jul 31 2018, 03:11 PM
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Senior Member Group: Members Posts: 846 Joined: 24-July 06 From: Watkinsville,GA Member No.: 6,499 Region Association: None |
On our 1.8 FProd car (12.3:1 CR) CDI made zero power difference. It did crap out, though, while leading a race at Barber.
I rigged up a back up system I could switch back and forth between on the fly. The back up was a Bosch Blue Coil with no CDI. We tested both systems on the chassis dyno and there was absolutely zero difference in torque or power. We were using a Mallory distributor. Crank fire might be a different story. We ditched the CDI and the attendant complications. |
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| Mark Henry |
Aug 1 2018, 10:13 AM
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that's what I do! Group: Members Posts: 20,065 Joined: 27-December 02 From: Port Hope, Ontario Member No.: 26 Region Association: Canada |
QUOTE(HAM Inc @ Jul 31 2018, 05:11 PM)  On our 1.8 FProd car (12.3:1 CR) CDI made zero power difference. It did crap out, though, while leading a race at Barber. I rigged up a back up system I could switch back and forth between on the fly. The back up was a Bosch Blue Coil with no CDI. We tested both systems on the chassis dyno and there was absolutely zero difference in torque or power. We were using a Mallory distributor. Crank fire might be a different story. We ditched the CDI and the attendant complications. Len how much do you think camber design has to do with this? I've always been on the fence with stock vs fancy ignitions for a /4. For most apps with a T1 and T4 I've never seen any magical power difference between stock and CDI (etc.) The only improvement I've seen has been the off idle issue that some engines have. Where as the /6 uses a CDI from the factory, except for early stock engines and everyone uses a high output ignition system of some type. I use a crankfire on my 180hp 2600cc T4 with aftermarket FI, 44X38mm valves... runs great. But I've also built a similar spec carbed 2700cc T4, used a mallory with just a blue coil I didn't see any real difference ignition wise. |
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Posts in this topic
Driver174 Capacitive Discharge Ignition Jul 30 2018, 08:33 PM
Mark Henry Yes and no :D
In your case the with the much hi... Jul 30 2018, 10:20 PM
sithot
Yes and no :D
In your case the with the much h... Jul 31 2018, 06:00 AM McMark CDI and MSD are two different things:
CDI: Capaci... Jul 31 2018, 11:07 AM mb911 Mark,
I believe the msd is as you describe but al... Jul 31 2018, 11:22 AM McMark You're right, the 6AL does seem to have CDI bu... Jul 31 2018, 11:34 AM Mark Henry Yep MSD is a CDI. Jul 31 2018, 12:56 PM mb911 Len,
Very interesting. Jul 31 2018, 03:13 PM Driver174
On our 1.8 FProd car (12.3:1 CR) CDI made zero po... Jul 31 2018, 03:42 PM worn
914-4 2L race engine, 10.3:1 compression ratio an... Jul 31 2018, 07:38 PM Mueller Pay for shipping and I'll send you an MSD 6A, ... Jul 31 2018, 08:02 PM RoadGlue
Pay for shipping and I'll send you an MSD 6A,... Aug 1 2018, 09:37 AM Driver174
Pay for shipping and I'll send you an MSD 6A,... Jul 31 2018, 11:28 PM McMark Mark, my thoughts center around the idea that ther... Aug 1 2018, 10:38 AM HAM Inc We all know the hemi chamber with dome pistons is ... Aug 1 2018, 03:04 PM Mark Henry
We all know the hemi chamber with dome pistons is... Aug 1 2018, 04:04 PM HAM Inc
We all know the hemi chamber with dome pistons i... Aug 1 2018, 04:23 PM Rand At the risk of this sounding like a dumb question:... Aug 1 2018, 04:16 PM Driver174
Yes and no :D
In your case the with the much h... Aug 1 2018, 04:45 PM |
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