TBI distributor 454/7.4L

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Sgt Gus

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Ugh,
My 454, TBI distributor is a .427 shaft, I need a .491 or .500 to order a distributor melonized gear for comp hydraulic roller(11-412-8). They don't make one for the .427
Replace the distributor and coil?
I am having a hard time finding one.
Recommendations pretty please
#gmbellew #catbox
 
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Ricko1966

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Sgt Gus said:
Ugh,
My 454, TBI distributor is a .427 shaft, I need a .491 or .500 to order a distributor melonized gear for comp hydraulic roller(11-412-8). They don't make one for the .427

Replace the distributor and coil?
I am having a hard time finding one.

Recommendations pretty please
Click to expand...
I'd make a bushing,either make the OD .0005 to big or the ID .0005 to small,use heat and a freezer to put the 2 together. Meaning if the ID is too small heat the bushing freeze the distributor put the 2 together,when the temps equalize it will be 1 piece. Come to think of it I'd make the OD of the bushing,ID of the gear my interference,you can get more expansion on the larger diameter. So it would be heat the distributor gear freeze the bushing.
 
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bucket

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Sgt Gus said:
Ugh,
My 454, TBI distributor is a .427 shaft, I need a .491 or .500 to order a distributor melonized gear for comp hydraulic roller(11-412-8). They don't make one for the .427

Replace the distributor and coil?
I am having a hard time finding one.

Recommendations pretty please
Click to expand...

Are you positive you need a melonozed gear? A lot of Comp's BB hydraulic roller cams don't require one.

Besides that, MSD offers a fancy drop-in distributor. The big block uses the same distributor as a small block too, unless you have a tall deck block.
 
Sgt Gus

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bucket said:
Are you positive you need a melonozed gear? A lot of Comp's BB hydraulic roller cams don't require one.

Besides that, MSD offers a fancy drop-in distributor. The big block uses the same distributor as a small block too, unless you have a tall deck block.
Click to expand...
I am rereading, machinist thought so.
I may call comp tomorrow.
 
Sgt Gus

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So, yes comp says their special gear is required or a melonized one per engine shop.
Easiest to replace distributor for tbi...?
 
Bextreme04

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Sgt Gus said:
So, yes comp says their special gear is required or a melonized one per engine shop.
Easiest to replace distributor for tbi...?
Click to expand...
Factory 97-up 7.4L distributor gear is the answer here. I put one on my 97 K2500 454 when I rebuilt everything. It's a factory AC Delco part. GM PN 10457708

Its a melonized gear for the factory billet hydraulic roller cams.
 
Sgt Gus

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Bextreme04 said:
Factory 97-up 7.4L distributor gear is the answer here. I put one on my 97 K2500 454 when I rebuilt everything. It's a factory AC Delco part. GM PN 10457708

Its a melonized gear for the factory billet hydraulic roller cams.
Click to expand...
What diameter will it fit? Mine is .427, and most are .491 or .500
 
Bextreme04

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Sgt Gus

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Sgt Gus

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bucket

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I'd trust the Summit part. It's just the price that a part like that should be, without the performance markup of the name brands.
 
Sgt Gus

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I'm gonna get that summit gear and put on our old remanufactured distributor and have as a replacement.
For now I got an MSD-5591 made for it with melonized gear. Verified with MSD engineer with phone call. .491 dia shaft ‍
Current appears to be remanf #1103749, .427 dia.
I think original ACDelco is 1103952. You can find alot of reman on internet for those. Not sure the dia. of shaft.
Current ACDelco replacement should be 19179575 per gm/ACDelco website. It does not give a diameter. Cost $$$$, but can find on net for $320-360.
It does say via some support person made for newer hydraulic roller cams, but mentions gear is not melonized.
That's what I got if helpful to anyone in decision making process.
 

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