Which flywheel for an ATK engine ?
Thread Starter
5th Gear
Joined: Apr 2019
Posts: 5
Likes: 0
From: Maubec / FRANCE
Which flywheel for an ATK engine ?
Hello the forum,
I bought an ATK crate engine for my old 81's Vette with original 4 speed manual gear box.
This ATK is a HP291-P with 1 piece rear main seal, and External rear, internal front blanced.
So, i don't know which sort of flywheel i need.... internal, external, neutral ?
Just i know : 11" clutch, 168 t.... and 1 piece RMS... 350CI GM.
Could you help me to decide ? Or the best, give the right reference of a right flywheel ;-) (On the Sum..t catalog)
You already understood my first language is not english....sorry. Hoping you can undertsand what i mean.
Thank you in adavance.
Didier from France
I bought an ATK crate engine for my old 81's Vette with original 4 speed manual gear box.
This ATK is a HP291-P with 1 piece rear main seal, and External rear, internal front blanced.
So, i don't know which sort of flywheel i need.... internal, external, neutral ?
Just i know : 11" clutch, 168 t.... and 1 piece RMS... 350CI GM.
Could you help me to decide ? Or the best, give the right reference of a right flywheel ;-) (On the Sum..t catalog)
You already understood my first language is not english....sorry. Hoping you can undertsand what i mean.
Thank you in adavance.
Didier from France
Thread Starter
5th Gear
Joined: Apr 2019
Posts: 5
Likes: 0
From: Maubec / FRANCE
I asked the question to Matt from ATK.... but he doesn't replyed (my english is not good....;-))
I need the right item because i'm afraid of making a mistake....
Thanks for your answer.
I need the right item because i'm afraid of making a mistake....
Thanks for your answer.
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
Hello the forum,
I bought an ATK crate engine for my old 81's Vette with original 4 speed manual gear box.
This ATK is a HP291-P with 1 piece rear main seal, and External rear, internal front blanced.
So, i don't know which sort of flywheel i need.... internal, external, neutral ?
Just i know : 11" clutch, 168 t.... and 1 piece RMS... 350CI GM.
Could you help me to decide ? Or the best, give the right reference of a right flywheel ;-) (On the Sum..t catalog)
You already understood my first language is not english....sorry. Hoping you can undertsand what i mean.
Thank you in adavance.
Didier from France
I bought an ATK crate engine for my old 81's Vette with original 4 speed manual gear box.
This ATK is a HP291-P with 1 piece rear main seal, and External rear, internal front blanced.
So, i don't know which sort of flywheel i need.... internal, external, neutral ?
Just i know : 11" clutch, 168 t.... and 1 piece RMS... 350CI GM.
Could you help me to decide ? Or the best, give the right reference of a right flywheel ;-) (On the Sum..t catalog)
You already understood my first language is not english....sorry. Hoping you can undertsand what i mean.
Thank you in adavance.
Didier from France
Perfection pn 50-6525
https://www.summitracing.com/parts/pft-50-6525
Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
OP
IF ... IF ... IF I shopped for a motor like that ATK ... I would Not buy that ATK
Instead, I would buy the BluePrint BP3503CT1 for $250 more ... because it has Much Better Vortec Heads and a Roller Cam and already Broken-in on dyno.
uses same flywheel and balancer/damper as ATK
https://www.summitracing.com/parts/m...3ct1/overview/
IF ... IF ... IF I shopped for a motor like that ATK ... I would Not buy that ATK
Instead, I would buy the BluePrint BP3503CT1 for $250 more ... because it has Much Better Vortec Heads and a Roller Cam and already Broken-in on dyno.
uses same flywheel and balancer/damper as ATK
https://www.summitracing.com/parts/m...3ct1/overview/
Le Mans Master
Joined: Oct 2006
Posts: 6,842
Likes: 285
From: Palmdale CA
Check your messages, I have a brand new Centerforce Steel Billet flywheel ($300, CTF-700160), that only has one hour of use, that was not the correct flywheel for my blueprinted and balanced 383 rebuild (the machine shop that skimmed the surface rust off of the flywheel I got with my rotating kit, three years ago for my one piece crank, told me, that the flywheel was not for a one piece rear seal, and they were wrong, it has a 3.0 bolt diameter, versus the 3 5/8 diameter for a two piece rear seal). I purchased the Centerforce billet flywheel two weeks ago, mounted it and now my engine is out of balance! I'm back to now mounting the supposed 'wrong' flywheel back on my engine within the next week or two. That one, has a huge counterweight welded to it and was balanced with the rest of the rotating kit that I purchased and had waiting for this build. I can show receipts and photos. It is SFI approved as well.
Thread Starter
5th Gear
Joined: Apr 2019
Posts: 5
Likes: 0
From: Maubec / FRANCE
Hi every body !
Thank you for your messages.
Just FYI, the last engine on my Vette was a 5 stars engine rebuild.... a big **** since the first day ! The ATK can't be more rotten....
No run with this old Corvette.
So, 1 piece RMS, 168th and EXTERNAL balance would be the good one as this one : https://www.summitracing.com/parts/pft-50-6525
or this one : https://www.summitracing.com/int/parts/nal-14088648
If you confirm, i'll place the order asap. Waiting for your confirmations !
Hate to read you soon. Thanks again (and sorry for this frogger english)
Didier
Thank you for your messages.
Just FYI, the last engine on my Vette was a 5 stars engine rebuild.... a big **** since the first day ! The ATK can't be more rotten....
No run with this old Corvette.
So, 1 piece RMS, 168th and EXTERNAL balance would be the good one as this one : https://www.summitracing.com/parts/pft-50-6525
or this one : https://www.summitracing.com/int/parts/nal-14088648
If you confirm, i'll place the order asap. Waiting for your confirmations !
Hate to read you soon. Thanks again (and sorry for this frogger english)
Didier
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Le Mans Master
Joined: Sep 2001
Posts: 7,739
Likes: 630
From: Unreconstructed, South Carolina
and ... as this ATK is all of 330hp ... that's why I suggested perfection 50-6025 ... also, me and thousands of others ran cheap perfection 16 pound 153T in circletrack ... granted mostly rolling starts, all asphalt, lotsa hard on-off bursts. No flywheel issues, ever. Now don't kid yourselves ... of course they ARE asian.
Thread Starter
5th Gear
Joined: Apr 2019
Posts: 5
Likes: 0
From: Maubec / FRANCE
and ... as this ATK is all of 330hp ... that's why I suggested perfection 50-6025 ... also, me and thousands of others ran cheap perfection 16 pound 153T in circletrack ... granted mostly rolling starts, all asphalt, lotsa hard on-off bursts. No flywheel issues, ever. Now don't kid yourselves ... of course they ARE asian.
Not a surprise for an asian product.... at this price.
But the right quality, at the right place for the right price : No drag with 330hp !! ;-)