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Old 08-11-2022, 02:05 PM
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Default Planning turbo engine build

I have some 32cc dish pistons in a 4.25 bore diameter that I want to use. I am planning on using these pistons. My thought is on what crank I would like to use. Should I use the offering from Molnar in a 4” stroke or should the 4.25” stroke. This is not some max effort engine, but should run good.

I have my 74cc combustion chamber aluminum Kre Dports for cylinder heads. With the 4” stroke I will get 454 cubic inches at about 9.04:1 compression. With the 4.25” stroke I will have 482 CI at about 9.54:1 compression. I have the turbo manifold already set up for a single turbo. I am thinking of using s S400 or an S480.

This is not a total budget build, but I do need to spend my money wisely to get it done.

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67 Firebird 467 cubic inches 7.71 @ 92 in the 1/8 and 11.69 @ 115 in the 1/4.
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Old 08-11-2022, 02:46 PM
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I'd go with the 4-in stroke. either stroke it'll be a really cool build. Good luck

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Old 08-11-2022, 03:11 PM
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What's the CH of the pistons?

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Old 08-11-2022, 04:07 PM
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Travis Quillen told me some years ago, that he should have gone with a 4" stroke vs a 4.25 stroke
(482 cid in their 4.25 stroke Twin Turbo engine).

Tom V.

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Old 08-11-2022, 06:03 PM
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I’m currently gathering parts for my twin turbo build. After long discussions with very smart people who have been there and done that, I will be going with a 4” stroke. The extra load on the cylinder walls with a 4.25” stroke is not worth it. Don’t worry about the cubic inches, let the turbos make the power.

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Old 08-11-2022, 06:10 PM
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For a turbo recommendation try https://www.forcedperformance.shop/ and ask for Robert

This is a good video regarding journal bearings and ball bearing turbos

https://youtu.be/zEVEAnRdEF4

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Old 08-11-2022, 06:48 PM
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Thank you so much guys. I really appreciate your feedback about Travis Tom. He is an extremely smart guy. I will jump on Johnny’s amok at buy and hope we can get a deal going.

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Old 08-11-2022, 06:49 PM
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Quote:
Originally Posted by AG View Post
What's the CH of the pistons?
I will have to check AG. I bought them years ago and they are in my storage unit.

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Old 08-11-2022, 06:52 PM
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Thank you Charlie. I need to try and move this build forward.

Thank you for the videos R 70 Judge. I appreciate your feedback.

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Old 08-11-2022, 07:50 PM
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Quote:
Originally Posted by quick67bird View Post
Thank you so much guys. I really appreciate your feedback about Travis Tom. He is an extremely smart guy. I will jump on Johnny’s amok at buy and hope we can get a deal going.
Smart enough that he is a "ROCKET MAN" for NASA these days vs a Pontiac Hot Rodder.

Tom V.

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Old 08-11-2022, 08:08 PM
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Keep us posted. I hope you figure it out to your liking . Sounds like you have most of the stuff . Even if you used a 3.75 stroke it be killer...

Im using a 3.75 in the motor im building now .. I have no doubt it will have more power/torque then ill ever need..

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Old 08-11-2022, 08:17 PM
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Thank you Charlie. I have collected a few parts over the years. I just need the crank, aftermarket block, crank, turbo and figure out an induction system.

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Old 08-11-2022, 09:05 PM
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Quote:
Originally Posted by quick67bird View Post
Thank you Charlie. I have collected a few parts over the years. I just need the crank, aftermarket block, crank, turbo and figure out an induction system.
I’m using a Northwind with a Steve Morris billet elbow and a Wilson’s 105mm throttle body with Holley Terminator X EFI. I have thread going in the EFI tech section if you want to duplicate anything.

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Old 08-15-2022, 01:30 PM
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I recommend you get the ring lands hard coated/ Anodized -- It will really help in the long run.

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Old 08-15-2022, 09:34 PM
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Curt is there someone local to us to do the anodizing or do the pistons need shipped off?

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67 Firebird 467 cubic inches 7.71 @ 92 in the 1/8 and 11.69 @ 115 in the 1/4.
  #16  
Old 09-23-2022, 06:52 PM
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A few people asked to see my turbo manifolds that I bought a few years ago. I finally was able to make it out to my storage unit to get some pictures. Here they are if you all have any more questions let me know.
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67 Firebird 467 cubic inches 7.71 @ 92 in the 1/8 and 11.69 @ 115 in the 1/4.
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Old 09-24-2022, 01:26 PM
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Hope they PACKAGE as good as they look in your vehicle.

Have fun. Tom V.

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Old 09-24-2022, 02:23 PM
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If this is a factory block are you planing to fill it up to the bottom of the front timing cover water passages.

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Old 09-24-2022, 05:41 PM
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Quote:
Originally Posted by Tom Vaught View Post
Hope they PACKAGE as good as they look in your vehicle.

Have fun. Tom V.
I have mocked them up in my car and the turbo will sit real close to where the battery used to be in my Firebird. I will weld up a support to help support the turbo on the passenger front frame rail. I have been trying to do this build for a while. I start to get frustrated and think I will just sell everything. I just keep telling myself that the parts aren’t costing me anything sitting there. Thank you for your insight Tom.

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67 Firebird 467 cubic inches 7.71 @ 92 in the 1/8 and 11.69 @ 115 in the 1/4.
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Old 09-24-2022, 05:47 PM
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Quote:
Originally Posted by 25stevem View Post
If this is a factory block are you planing to fill it up to the bottom of the front timing cover water passages.
Hey Steve the plan is to get an aftermarket block. I figure that would be the best way to go since I already have the dished pistons for a 4.25 bore.

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67 Firebird 467 cubic inches 7.71 @ 92 in the 1/8 and 11.69 @ 115 in the 1/4.
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