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HEI upgrade for 68 BB

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Old Apr 19, 2016 | 09:41 PM
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Default HEI upgrade for 68 BB

I have original transistorized ignition and it's still functional ok. Want to be ready to do an upgrade to either a new style unit or a late 70s unit. I'd like to hear what others have used. Does the car perform better than the original 45yr old system?
thanks
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Old Apr 19, 2016 | 11:16 PM
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If the distributor is working properly (advance curve, etc) along with the coil and the rest of the ign parts, you will not see any difference.

But, you might have more reliability with a new ignition....
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Old Apr 19, 2016 | 11:29 PM
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My 496 is stilling using the 69 distributor with but with the points removed using the Breakerless-SE
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Old Apr 20, 2016 | 12:22 AM
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Originally Posted by Jims427400
I have original transistorized ignition and it's still functional ok. Want to be ready to do an upgrade to either a new style unit or a late 70s unit. I'd like to hear what others have used. Does the car perform better than the original 45yr old system?
thanks

A large-cap HEI won't clear the stock wiper motor so you'd have to change the wiper motor to a later version. No big deal but if you decided to use an HEI make sure it has a premium module in it like a Standard, Accel, or MSD module even though they cost a lot more. When it comes to ignition modules you DO get what you pay for.
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Old Apr 20, 2016 | 07:35 AM
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Keep what you have.
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Old Apr 20, 2016 | 08:31 AM
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if it works keep it. mine didn't so it has this:
Mallory unilite electronic conversion MAL-501 ignition
MSD series 6 CDI box (Mallory is optical pickup replacing points, to msd CDI, to coil)

it works perfectly but obviously does not look stock with the CDI box.
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Old Apr 20, 2016 | 08:36 AM
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Clearance issues is one of my concerns.Just put in a new wiper motor so not interested in changing that. I am glad to hear that old vs new the car should run the same.
I'll have to look into how to check my advance curve.
Thanks all
Originally Posted by Mountainoakie
A large-cap HEI won't clear the stock wiper motor so you'd have to change the wiper motor to a later version. No big deal but if you decided to use an HEI make sure it has a premium module in it like a Standard, Accel, or MSD module even though they cost a lot more. When it comes to ignition modules you DO get what you pay for.
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Old Apr 20, 2016 | 09:09 AM
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Originally Posted by Jims427400
Clearance issues is one of my concerns.Just put in a new wiper motor so not interested in changing that. I am glad to hear that old vs new the car should run the same.
I'll have to look into how to check my advance curve.
Thanks all
You can get a timing tape from speed shop and use a normal timing light .That's low cost way .If you need mor help let me know
Wes
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Old Apr 20, 2016 | 09:22 AM
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I have a late 68 with a 454 and put the dragonfire tachdrive hei in mine and it all fit fine. I've been happy with it and it was less than $100.
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Old Apr 20, 2016 | 10:25 AM
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I also installed a tachdrive big head hei in my 69 427 fit fine and improves performance
get new hei wires and re gap the plugs 40-45.
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Old Apr 20, 2016 | 10:53 AM
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Default TI Ignition

Originally Posted by Jims427400
Clearance issues is one of my concerns.Just put in a new wiper motor so not interested in changing that. I am glad to hear that old vs new the car should run the same.
I'll have to look into how to check my advance curve.
Thanks all
Contact the company below to have your current TI system upgraded to modern components.
http://www.tispecialty.com/
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Old Dec 21, 2016 | 02:36 AM
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Default Wiper motor clearance

Originally Posted by Mountainoakie
A large-cap HEI won't clear the stock wiper motor so you'd have to change the wiper motor to a later version. No big deal but if you decided to use an HEI make sure it has a premium module in it like a Standard, Accel, or MSD module even though they cost a lot more. When it comes to ignition modules you DO get what you pay for.
I don't suppose anyone can confirm which (if any!) std wiper motor/washer assemblies will not have clearance issues in a bb 68?
Thanks!
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Old Dec 21, 2016 | 03:10 AM
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Originally Posted by Dave Vincec
I don't suppose anyone can confirm which (if any!) std wiper motor/washer assemblies will not have clearance issues in a bb 68?
Thanks!
I installed a large cap tach drive in a BBC 69 with no issues. You cannot use the shields though.
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Old Dec 21, 2016 | 03:40 AM
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Originally Posted by Big2Bird
I installed a large cap tach drive in a BBC 69 with no issues. You cannot use the shields though.


This is a non tach drive unit (i've got a kit to convert the mechanical tach to electronic - but thats a bit further down my job list )


pic below; i've just sat the screen washer assy back in situ for the purposes of demonstration - but you can see that even without the cover its a pretty tight fit!


how far does the cover protrude beyond the bits that I have? it might squeeze...
Attached Images  
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Old Dec 21, 2016 | 10:58 PM
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HEI dist. with tach drive will drop right into 68-69,
no wiper motor issues,
IF your current dist. is working correctly you will not gain much in performance.
you will get larger spark gap. .040 and slightly higher coil voltage.
you will have Breather clearance issuses, and of course old Chrome Dist. cover will not fit.


Last edited by 69Vett; Dec 21, 2016 at 11:03 PM.
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Old Dec 24, 2016 | 04:35 PM
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Default 68 BB Distributor issues

I have a 1968 Corvette and mine came with the factory T.I. as well. I took mine out and sent the box and the distributor to the folks at T.I. Specialties (Dave Fiedler) and they rebuilt the distributor and he installed the updated board. He returned all the original pieces from the rebuild, a very high quality shop! When I got it back from Dave I put the box on a shelf in my garage.
I am using a MSD Corvette Distributor (with Tach drive) and a MSD 6A controller with a another MSD box that retards my ignition while cranking. My 427 has 12.25-1 Compression ratio with "Closed Chamber" heads from a 1965 396 Corvette. It cranks real slowly with that compression unless you use and a gear drive starter or turn the timing back 20 degree while cranking. I did both and it cranks like a "Chrysler".

I have been very happy with the MSD setup, it has worked reliably for over 15 years.
Someday if somebody wants to put my Corvette back to all original they are welcomed to the original parts.
Good Luck!
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