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I was very lucky where I took my motor to have all the block machine work done. One guy there does head porting work on the side with a flow bench. He does lots of LS stuff. The guy said that the out of the box heads are usually in need of attention and bare heads are the best option. I am so glad I started buying stuff years ago for this project.
 

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Discussion Starter · #42 ·
I have put everybody's data in a spreadsheet, but had to convert it to a pdf to upload to the thread. It is attached to the first post of this thread. I will update it as more builds are posted. If you want the Excel spreadsheet, PM me with your email address.
 

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Discussion Starter · #43 ·
I have been doing some research to go along with my dreaming of the stroker engine build. I have estimated that I can buy a stroker engine kit that ranges from a 463 to a 490 cubic inches for $2400 to $3400. These cubic inches were generated by using their custom piston options, and an assumed 40-over bore. I used Butler's site to come to these conclusions since it's pretty easy to select the options and build a total price. I pretty much went with the middle of the road upgrades for options and found that the extra money you need to spend to get from the 463 to the 490 is about a thousand dollars...$37 per cubic inch. I am thinking that a 9 to 9.5:1 compression ratio should be my goal.

Here's a couple question for those of you who have built one of these engines...

Given I have the extra thousand, why would I not build the larger 490 cu-in stroker engine?

I intend to use the stock 4bbl intake, HO exhaust mani's, 670 heads - all port matched - and a Ram Air-like cam...if that makes a difference.
 

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Nice work, thanks ! It shows the ignition for mine is the Blaster but I have the MSD R2R..no biggie. What is your main use for the car, are you shooting for a certain HP, or TQ number, do you have the drive line to support,??? Idk but you can build a pretty potent 461 and put the extra 1k into something else imo. Is 490 going to be that much more powerful than 461,463,467 idk?
 

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Discussion Starter · #45 ·
Baaad65 , I corrected the spreadsheet...thanks for the proof read. I wonder where the Blaster even came from? I have updated the file on the original post. Somebody else's data is probably wrong...hmmm?

My build is pretty much an open book. My goals are...

91-93 octane.
Street-able.
To stay around 1 horse power per cubic inch.
Rear Gear Ratio around the mid to low 3's, Maybe a 12 bolt for the strength.
Get traction, not smoke, so drag radials are a possibility, no tubbing.
Keep a very stock look to the engine (and car).

I will drive this car on sunny days to work and want to do it "fast"...lol
 

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Sounds like a good plan 👌 I have a 12bolt 3:42 with a 2.99 first gear...giddy up. 275 drag radials and lift bars and still can't side step the clutch, around 530 lbs torque 😎
 

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1 OEM Block Size (ie 326, 389, 400, 455. etc) - 400
2 Crank Size Used (ie 400, 455, etc) - Cast Eagle 4.250 stroke, 3.00 mains
3 Stroker Kit Used (ie 461, 467, 471, etc) - 467
4 Final Bore Diameter - 4.181"
5 Final Deck Height - ???
6 Piston (Type, Make & Model) - Ross/Butler 4.181 x 1.295 CH (6.800 x 4.250 stroke) Flat Top Forged
7 Compression Ratio (Static) - 10.3
8 Compression Ratio (Dynamic) - ???
9 Heads (Make & Model) - Pontiac Iron 6X-4 with mild porting and multi angle valve work done locally
10 Head Valve Size (Intake & Exhaust) - 2.11" intake, 1.66" exhaust
11 Head Chamber Size (Actual in cc's) - 93.74
12 Head gasket thickness - .040
13 Intake to Head Port Matched? - No
14 Head to Exhaust Port Matched? - No
15 Intake (Make & Model) - Edelbrock P65 dual plane dual four barrel carburetors
16 Exhaust Manifolds or Headers - RARE oversized ram air reproductions
17 Exhaust Manifolds or Headers (Make & Model) - 64-67 2.5" outlet RA Manifolds, ceramic coated
18 Carburetor (Make & Model) - Edelbrock 1405 and 1406 600CFM carburetors with 1:1 linkage
19 Cam (Make & Model) - Butler/Comp Cams Extreme Energy XE 274 HFT
20 Cam Specs - 274/286, 230/236, .488/.491, 110 (If I ever change, I may try the 068 grind)
21 Rocker Ratio - 1.52
22 Rocker Type (Stamped or Roller) - Stamped with roller tip
23 Rocker (Make & Model) - Comp Cams Magnum Roller tip
24 Push Rod Length - 9.130
25 Estimated Flywheel Horse Power - ???
26 Dyno'd Flywheel Horse Power - ???
27 Dyno'd Horse Power at the rear tires - I have no idea but my 400s never had near this much torque!
28 Lifter Type (Solid, Hydraulic Tappet, or Roller) - Hyd Flat Tappet
29 Lifter (Make & Model) - Comp Cams standard Pontiac
30 Ignition: - Pertronix Flame Thrower, MSD 6AL with rev limiter and remote timing control
31 Fuel Octane - 95 to 100? Depends if I want to run with timing set at 16 or 18. 18 runs better and cooler.
32 How do you get to that octane (91, 93, + additive w/brand, race fuel mix, etc) -93 plus Octane Supreme. I may be changing to VP Octanium for a variety of reasons (cost, availability, toxicity).
 

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I have been doing some research to go along with my dreaming of the stroker engine build. I have estimated that I can buy a stroker engine kit that ranges from a 463 to a 490 cubic inches for $2400 to $3400. These cubic inches were generated by using their custom piston options, and an assumed 40-over bore. I used Butler's site to come to these conclusions since it's pretty easy to select the options and build a total price. I pretty much went with the middle of the road upgrades for options and found that the extra money you need to spend to get from the 463 to the 490 is about a thousand dollars...$37 per cubic inch. I am thinking that a 9 to 9.5:1 compression ratio should be my goal.

Here's a couple question for those of you who have built one of these engines...

Given I have the extra thousand, why would I not build the larger 490 cu-in stroker engine?

I intend to use the stock 4bbl intake, HO exhaust mani's, 670 heads - all port matched - and a Ram Air-like cam...if that makes a difference.
Sorry late to the party here. I'm thinking one thing you would want to find out is if you would need to clearance the block to go with a 490 ci build. With what your intended use is, you may just be making a car that's already going to be bad on gas even worse. A 461/467 build is going to be blisteringly fast in a street car.
 
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