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Tech Talk => Engine Mechanical / Electrical => Topic started by: Mothyu812 on September 28, 2015, 10:26:59 PM

Title: 498 big block Chevy
Post by: Mothyu812 on September 28, 2015, 10:26:59 PM
I have a scat crank and I'm trying to figure out what internal flex plate to use. It's a mark 4 block 454


I have a scat crank and I'm trying to figure out what internal flex plate to use. It's a mark 4 block 454
Title: Re: 498 big block Chevy
Post by: jyeager on September 28, 2015, 10:53:41 PM
Bostick to the SCJB curtesy phone.


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Title: Re: 498 big block Chevy
Post by: jimpen on September 29, 2015, 06:09:49 AM

I have a scat crank and I'm trying to figure out what internal flex plate to use. It's a mark 4 block 454


I have a scat crank and I'm trying to figure out what internal flex plate to use. It's a mark 4 block 454
. I'm going to guess you are looking for a flex plate. And your asking if it is internal or eternal balanced. If that is the case you should have a internally balanced motor. I would use a non weighted flex plate. I use a TCI flex plate   


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Title: Re: 498 big block Chevy
Post by: Flusher on September 29, 2015, 07:36:05 AM
Do you have a balance card or any documentation on the engine?   Can you look at the back of the damper to see if it has a counterweight or not?
Title: Re: 498 big block Chevy
Post by: Flusher on September 29, 2015, 07:37:33 AM
Or do you know for sure that it is internally balanced?
Title: Re: 498 big block Chevy
Post by: Mothyu812 on September 29, 2015, 05:30:38 PM
Yes it is internally balanced I'm trying to figure out what flexplate to buy


I have a scat crank and I'm trying to figure out what internal flex plate to use. It's a mark 4 block 454
Title: Re: 498 big block Chevy
Post by: Flusher on September 29, 2015, 06:35:06 PM
Where is your starter located?  Most likely it will be a 168-tooth flexplate.  If you are using a mini-starter mounted to the block in the factory location, some mini-starters have two sets of holes, allowing the use of 153-tooth flexplates.  Which one you choose is primarily dictated by how/where your starter is mounted.

Any SBC and BBC flywheel or flexplate for a two-piece seal crankshaft will physically bolt on.  Just be advised that the external balance flywheels/flexplates have different balance weights between SBC and BBC.

As far as the Mark IV Scat crankshaft, the only difference is the material and the design of the counter weights.  Since you know that your engine is internally balanced, that's a done deal.

Hope this is the info you are looking for.

Cheers

Joe
Title: Re: 498 big block Chevy
Post by: jimpen on September 29, 2015, 08:24:34 PM
This is what use


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Title: Re: 498 big block Chevy
Post by: Mothyu812 on September 29, 2015, 10:47:53 PM
Thank you for your help


I have a scat crank and I'm trying to figure out what internal flex plate to use. It's a mark 4 block 454
Title: Re: 498 big block Chevy
Post by: BCouey on September 29, 2015, 11:38:53 PM
Soooo I have a question, not so much a help to you but anyway.... Why a flex plate vs a flywheel? I have an aluminum flywheel on my setup, seems to work fine


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Title: Re: 498 big block Chevy
Post by: jimpen on September 30, 2015, 06:13:57 AM

Soooo I have a question, not so much a help to you but anyway.... Why a flex plate vs a flywheel? I have an aluminum flywheel on my setup, seems to work fine


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no reason just have always had a flex plate. Your setup may be better but when you broke teeth how long did it take to get it fixed. I carry a extra flex plate with me. I know you could get another flywheel just more money. From what I see out there is a lot more flex plates and I'm happy with mine. Just recently they had a big topic about this you could read on here


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Title: Re: 498 big block Chevy
Post by: Mothyu812 on September 30, 2015, 07:20:25 PM
The reason I'm doing flex plate . The Engine and transmission was set up for flexplate


I have a scat crank and I'm trying to figure out what internal flex plate to use. It's a mark 4 block 454
Title: Re: 498 big block Chevy
Post by: Mothyu812 on September 30, 2015, 07:22:13 PM
Two pictures


I have a scat crank and I'm trying to figure out what internal flex plate to use. It's a mark 4 block 454
Title: Re: 498 big block Chevy
Post by: Flusher on October 01, 2015, 02:30:03 PM
Do you have a starter (pictured) that has multiple mounting locations?  If not, you need the 168-tooth flexplate that Jim Penn posted.  Also looks like the hole in your engine plate is only for a 168-tooth flexplate.  350, 396, 427ci
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