Flex Plate Question
Drifting
Joined: Oct 2007
Posts: 1,317
Likes: 22
From: Marina CA
That's the engine side. Are you going to use this on an externally balanced engine? With the welded on counterweight it won't work on an internally balanced engine. It also looks to be a dual pattern flex plate. 3 of the converter mounting holes are closer to the ring gear and 3 lower down.
400sb and 454bb external balance.
350sb and 427bb internal balance.
I believe some of the 383 stroker motors balance externally.
400sb and 454bb external balance.
350sb and 427bb internal balance.
I believe some of the 383 stroker motors balance externally.
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
Likes: 126
From: San Diego California
1Fordman,
Thanks for the comeback.
That flex plate came with this 383 stroker kit;
http://www.ebay.com/itm/SBC-CHEVY-383-STROKER-KIT-SCAT-CRANK-RODS-030-FORGED-FLAT-TOP-PISTONS-2PC-RMS-/331231662680?pt=Motors_Car_Truck_Parts_Accessories&hash=item4d1ef21258
Here are the heads I chose for it;
http://www.ebay.com/itm/327-350-CHEVY-ALUMINUM-CYLINDER-HEADS-SBC-2-02-STRAIGHT-PLUG-190CC-/351130537292?pt=Motors_Car_Truck_Parts_Accessories&hash=item51c102cd4c
The finished product;
All this just to show if it's an internally or externally balanced engine. I have to admit I don't understand the difference of terms.
Steve
Thanks for the comeback.
That flex plate came with this 383 stroker kit;
http://www.ebay.com/itm/SBC-CHEVY-383-STROKER-KIT-SCAT-CRANK-RODS-030-FORGED-FLAT-TOP-PISTONS-2PC-RMS-/331231662680?pt=Motors_Car_Truck_Parts_Accessories&hash=item4d1ef21258
Here are the heads I chose for it;
http://www.ebay.com/itm/327-350-CHEVY-ALUMINUM-CYLINDER-HEADS-SBC-2-02-STRAIGHT-PLUG-190CC-/351130537292?pt=Motors_Car_Truck_Parts_Accessories&hash=item51c102cd4c
The finished product;
All this just to show if it's an internally or externally balanced engine. I have to admit I don't understand the difference of terms.
Steve
Drifting
Joined: Oct 2007
Posts: 1,317
Likes: 22
From: Marina CA
If your vibration dampener has the weight on the back side as shown in the ebay listing photo your engine balances externally. The flex plate in your photo is the correct one as it has the counterweight welded to it.
Nice looking engine by the way, should scoot down the road nicely!
Nice looking engine by the way, should scoot down the road nicely!
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
Likes: 126
From: San Diego California
If your vibration dampener has the weight on the back side as shown in the ebay listing photo your engine balances externally. The flex plate in your photo is the correct one as it has the counterweight welded to it.
Nice looking engine by the way, should scoot down the road nicely!
Nice looking engine by the way, should scoot down the road nicely!
Thanks again!
Question 2: Now that the engine is in (Flexplate was installed correctly), I've got quite a gap here. About 3/8 to a 1/2 inch.
Normal?
Steve
Drifting
Joined: Oct 2007
Posts: 1,317
Likes: 22
From: Marina CA
That gap is too wide. If you pull the converter ahead to bolt to the flex plate there wont be enough converter to pump engagement.
Ideally you want about 3/16" to 1/4" gap. You need to put some machined washers between the flex plate and converter mounting lugs.
With the converter bottomed in the front pump of the transmission you only want to pull it out 3/16" and fill the gap with equal thickness washers.
I have used grade 8 fender washers (larger diameter) and measured each one for thickness with digital readout calipers. Also use grade 8 bolts and nuts to mount the converter. Used grade 8 aircraft lock nuts on the last install. They have the nylon on the end of the nut that grabs the bolt.
Looks like you have a 10" stall converter.
Ideally you want about 3/16" to 1/4" gap. You need to put some machined washers between the flex plate and converter mounting lugs.
With the converter bottomed in the front pump of the transmission you only want to pull it out 3/16" and fill the gap with equal thickness washers.
I have used grade 8 fender washers (larger diameter) and measured each one for thickness with digital readout calipers. Also use grade 8 bolts and nuts to mount the converter. Used grade 8 aircraft lock nuts on the last install. They have the nylon on the end of the nut that grabs the bolt.
Looks like you have a 10" stall converter.
Last edited by 1Fordman; Oct 22, 2014 at 03:21 PM.
Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
Likes: 126
From: San Diego California
That gap is too wide. If you pull the converter ahead to bolt to the flex plate there wont be enough converter to pump engagement.
Ideally you want about 3/16" to 1/4" gap. You need to put some machined washers between the flex plate and converter mounting lugs.
With the converter bottomed in the front pump of the transmission you only want to pull it out 3/16" and fill the gap with equal thickness washers.
I have used grade 8 fender washers (larger diameter) and measured each one for thickness with digital readout calipers. Also use grade 8 bolts and nuts to mount the converter. Used grade 8 aircraft lock nuts on the last install. They have the nylon on the end of the nut that grabs the bolt.
Looks like you have a 10" stall converter.
Ideally you want about 3/16" to 1/4" gap. You need to put some machined washers between the flex plate and converter mounting lugs.
With the converter bottomed in the front pump of the transmission you only want to pull it out 3/16" and fill the gap with equal thickness washers.
I have used grade 8 fender washers (larger diameter) and measured each one for thickness with digital readout calipers. Also use grade 8 bolts and nuts to mount the converter. Used grade 8 aircraft lock nuts on the last install. They have the nylon on the end of the nut that grabs the bolt.
Looks like you have a 10" stall converter.
1Fordman,
I didn't think it was acceptable to use washers, or any kind of shim(s) for that matter, on the bolt up of a flex plate to the converter.
Steve
Pro
Joined: Apr 2013
Posts: 535
Likes: 8
From: London Ontario
Steve, the Scat kit is externally balanced and you need to use that flex plate. It also needs to be indexed into the correct alignment on the crank; there should be a mark or alignment holes to help.
Your issue with the torque converter looks like it may not be fitting into the back of the crank correctly. If you still have the engine out of the car test fit the TC to the assembled flex plate/crank flange. It wouldn't be the first time there was a protective sleeve or a pre-installed pilot bearing that wasn't noticed. Something is certainly holding it back, as, there should not be a need for spacers/washers. What bolts did you use to mount the flex plate? The correct bolts have a very thin head and no washers.
Tim
Your issue with the torque converter looks like it may not be fitting into the back of the crank correctly. If you still have the engine out of the car test fit the TC to the assembled flex plate/crank flange. It wouldn't be the first time there was a protective sleeve or a pre-installed pilot bearing that wasn't noticed. Something is certainly holding it back, as, there should not be a need for spacers/washers. What bolts did you use to mount the flex plate? The correct bolts have a very thin head and no washers.
Tim
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Thread Starter
Melting Slicks
Joined: Oct 2013
Posts: 2,569
Likes: 126
From: San Diego California
Steve, the Scat kit is externally balanced and you need to use that flex plate. It also needs to be indexed into the correct alignment on the crank; there should be a mark or alignment holes to help.
Your issue with the torque converter looks like it may not be fitting into the back of the crank correctly. If you still have the engine out of the car test fit the TC to the assembled flex plate/crank flange.
Yes, Tim, I pulled the engine this morning, and as it hung from the hoist, I fitted the TC onto the flexplate. It fit beautifully snug, with a set of 3 holes lining up perfectly.
It wouldn't be the first time there was a protective sleeve or a pre-installed pilot bearing that wasn't noticed. Something is certainly holding it back, as, there should not be a need for spacers/washers.
I may have confused you Tim. The pictures show the gap between TC and FP in order to show the distance the TC has to move out of the tranny in order to bolt up.
What bolts did you use to mount the flex plate? The correct bolts have a very thin head and no washers.
Tim
I bought a set of FP bolts (5) and yes, they have rather shallow heads. But they did come with thin star-lock washers.
Your issue with the torque converter looks like it may not be fitting into the back of the crank correctly. If you still have the engine out of the car test fit the TC to the assembled flex plate/crank flange.
Yes, Tim, I pulled the engine this morning, and as it hung from the hoist, I fitted the TC onto the flexplate. It fit beautifully snug, with a set of 3 holes lining up perfectly.
It wouldn't be the first time there was a protective sleeve or a pre-installed pilot bearing that wasn't noticed. Something is certainly holding it back, as, there should not be a need for spacers/washers.
I may have confused you Tim. The pictures show the gap between TC and FP in order to show the distance the TC has to move out of the tranny in order to bolt up.
What bolts did you use to mount the flex plate? The correct bolts have a very thin head and no washers.
Tim
I bought a set of FP bolts (5) and yes, they have rather shallow heads. But they did come with thin star-lock washers.
The gap in the picture represents the amount the TC has to come out of the tranny once bolted up to the FP. The tangs within the tranny I'm not sure how long they are. I do know the slots, or cutouts, on the TC's shaft are a good 1" in length. So, I'm just trying to find out if some knows if this distance is alright, or too much.
Steve
Pro
Joined: Apr 2013
Posts: 535
Likes: 8
From: London Ontario
Now I understand what your concern is. In my experience the TC will move back into the transmission far enough to pull out of the back of the crank for removal; 3/8"-1/2" in same cases. I think you will be fine.
Now get that thing together so we can see how it runs!
Now get that thing together so we can see how it runs!