Distributor Caps, whats the difference ?
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
Distributor Caps, whats the difference ?
I ordered a MSD dizzy cap (picture below) from Summitracing, I made sure i checked application, yes it says, '85 Corvette,
when it turned up i noticed it had long quarter turn clips, my distributor has 4 short screws so i cant use it,
So what does the long quarter turn cap fit ?? I looked at some on ebay and it would appear the long clips are C3 ?
I sent Summit an email saying their application list is wrong, but the response is "you better check with MSD, it should fit"
so before i send Summit a more strongly worded email, I thought I better check with the CF guru's
when it turned up i noticed it had long quarter turn clips, my distributor has 4 short screws so i cant use it,
So what does the long quarter turn cap fit ?? I looked at some on ebay and it would appear the long clips are C3 ?
I sent Summit an email saying their application list is wrong, but the response is "you better check with MSD, it should fit"
so before i send Summit a more strongly worded email, I thought I better check with the CF guru's
Team Owner
Joined: Jan 2003
Posts: 20,305
Likes: 240
From: Summerland B.C. Canada
Looking at Summit, I see you had 3 MSD choices. The first 2 list clamp down, while the third lists bolt down. They all say they fit 85, but it seems only one does.
http://www.summitracing.com/search/y...?Ns=Rank%7cAsc
Summit does need to correct this, and you need to read more of the info.
Can you replace the clamps for screws and make it work ? Long wet drive to get replacement.
http://www.summitracing.com/search/y...?Ns=Rank%7cAsc
Summit does need to correct this, and you need to read more of the info.
Can you replace the clamps for screws and make it work ? Long wet drive to get replacement.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
I ran into the same problem when I ordered a MSD Cap from Summit for my 87. It also uses a screw-down style cap. Not only is their catalog part number/description wrong, so is the MSD Catalog part number/description.
The MSD Website catalog is wrong. Maybe somebody from Summit should be working with MSD.
I wound up exchanging it for a Taylor cap and rotor (TAY-918131) and it was $4 cheaper. It's a good heavy cap with brass terminals just like the MSD cap.
The MSD Website catalog is wrong. Maybe somebody from Summit should be working with MSD.
I wound up exchanging it for a Taylor cap and rotor (TAY-918131) and it was $4 cheaper. It's a good heavy cap with brass terminals just like the MSD cap.
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
thanks for the info guys,
and yes agent86 I shouldnt be so naive as to think Summit and MSD would actually get their fitment details correct !
As far as modifying it, i would have to cut the angled clamps off and buy 4 screws the right length, or sell it to another c4 owner who doesnt know the difference !
and yes agent86 I shouldnt be so naive as to think Summit and MSD would actually get their fitment details correct !
As far as modifying it, i would have to cut the angled clamps off and buy 4 screws the right length, or sell it to another c4 owner who doesnt know the difference !
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
thanks for the info guys,
and yes agent86 I shouldnt be so naive as to think Summit and MSD would actually get their fitment details correct !
As far as modifying it, i would have to cut the angled clamps off and buy 4 screws the right length, or sell it to another c4 owner who doesnt know the difference !
and yes agent86 I shouldnt be so naive as to think Summit and MSD would actually get their fitment details correct !
As far as modifying it, i would have to cut the angled clamps off and buy 4 screws the right length, or sell it to another c4 owner who doesnt know the difference !
Racer
Joined: Jul 2010
Posts: 308
Likes: 2
From: Kansas City MO
Not to bail out Summit but they simply receive fitment information from their suppliers (in this case MSD) so any "wrong" information in the application listing is coming from MSD. I believe the MSD "replacement" distributor for the C4 used the more traditional clamp style so that may be what they're referring to as it "fits". Also - I think some of the generic (read real cheap) parts store replacements may have the clamps and not the screws so that they fit a lot more applications and thus can be mass produced cheaper... Just sucks since you're apparently overseas...
I looked at the summit link - they even have the filter to select "bolt down" or "clamp down" under the 'Cap Attachment Style' heading so they must know it's important to be able to select the style.
I looked at the summit link - they even have the filter to select "bolt down" or "clamp down" under the 'Cap Attachment Style' heading so they must know it's important to be able to select the style.
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Safety Car
Joined: Nov 2008
Posts: 4,328
Likes: 15
From: Jacksonville FL
I just put a new red Taylor screw down cap on my 85. Who designed the firewall where the cowl drip edge(18 torx screws) hasta come off to get to the back dizzy screw??? Sheesh. Your on the right track buying a quality cap. I always buy one that has brass terminals and you certainly dont wanna change it often with the PITA location.
Thread Starter
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
thanks for the feedback guys, you live and learn !
HlhnEast, I know what your saying about the tight fit, I thought i would do it while the TPI was off, I had to take the old cap off to put on the new rotor, used a 1/4" drive with a knuckle joint, did the trick on those back screws !
I am tempted to take the clamps off and buy longer screws, might be the easiest option ?
HlhnEast, I know what your saying about the tight fit, I thought i would do it while the TPI was off, I had to take the old cap off to put on the new rotor, used a 1/4" drive with a knuckle joint, did the trick on those back screws !
I am tempted to take the clamps off and buy longer screws, might be the easiest option ?
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
I just put a new red Taylor screw down cap on my 85. Who designed the firewall where the cowl drip edge(18 torx screws) hasta come off to get to the back dizzy screw??? Sheesh. Your on the right track buying a quality cap. I always buy one that has brass terminals and you certainly dont wanna change it often with the PITA location.
