Need advice on 3V 4.6 NA stroker build, any issues if running 10+ to 11CR?

Shakn68

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Getting ready to order my 5.0 stroker kit for an Aluminum 3V 4.6. I'd like to increase the CR slightly over the factory 9.8. Has anyone run a N/A 10+ up to 11CR and did it effect octane, Knock, or reliability in anyway? Currently run most bolt-on N/A mods with a tune. Please advise.
 

RED09GT

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These cars can tolerate a fair bit of compression, especially N/A. If you plan on staying N/A, going up to even 11.0:1 is fine with premium fuel. If you decide to do a power adder later on, it would be best to switch to E85, if available.
 
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Doug Huggard

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Getting ready to order my 5.0 stroker kit for an Aluminum 3V 4.6. I'd like to increase the CR slightly over the factory 9.8. Has anyone run a N/A 10+ up to 11CR and did it effect octane, Knock, or reliability in anyway? Currently run most bolt-on N/A mods with a tune. Please advise.
Are you planning on getting a forged crank with your stroker kit? Or the cast Eagle crank? The reason I ask is because if you are staying with a cast, I'd stick with your stock crank. Going stroker with these motors is known to add very little power over stock stroke, but you will get more piston wear due to the skirt dropping pretty far out of the bore at bdc. My recommendation would be stock crank(known to be very stout), boss rods and Manley flat top pistons. This would bring your compression to about 10.5-1, be a lightweight rotating assembly which would be very responsive through the rpm range and give you a little room compression wise to run pump gas if you decide to go FI later....which everyone does eventually lol
 

Dino Dino Bambino

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Here's a real world example of a N/A 302ci stroker build in a 2009 GT:

302ci Stroker & HCI

Livernois_302_Stroker.jpg

Combining a 3.800" stroker crankshaft with the 3.554" cylinder bore of an honed 3V block increases displacement from the stock 281ci (4601cc) to 302ci (4942cc). The compression ratio is also increased from 9.8:1 to 10.5:1 when using flat top pistons with 6.25cc valve reliefs. This stroker combination was dressed with Livernois stage 3 ported heads, XFI 127600 SPR camshafts, Livernois cam phaser limiters, FRPP intake manifold, FRPP dual 62mm throttle body, FRPP 39lb injectors, SPEC 12lb aluminum flywheel, and a
Shaftmaster aluminum driveshaft.

413.32rwhp 359.49rwtq (SAE corrected)
 

Shakn68

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These cars can tolerate a fair bit of compression, especially N/A. If you plan on staying N/A, going up to even 11.0:1 is fine with premium fuel. If you decide to do a power adder later on, it would be best to switch to E85, if available.
Appreciate the info, TY
 

Shakn68

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Here's a real world example of a N/A 302ci stroker build in a 2009 GT:

302ci Stroker & HCI

Livernois_302_Stroker.jpg

Combining a 3.800" stroker crankshaft with the 3.554" cylinder bore of an honed 3V block increases displacement from the stock 281ci (4601cc) to 302ci (4942cc). The compression ratio is also increased from 9.8:1 to 10.5:1 when using flat top pistons with 6.25cc valve reliefs. This stroker combination was dressed with Livernois stage 3 ported heads, XFI 127600 SPR camshafts, Livernois cam phaser limiters, FRPP intake manifold, FRPP dual 62mm throttle body, FRPP 39lb injectors, SPEC 12lb aluminum flywheel, and a
Shaftmaster aluminum driveshaft.

413.32rwhp 359.49rwtq (SAE corrected)
Nice build, thanks for sharing the Dyno test. Gives me something to shoot for.
 

GERMANSHEPERD

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My 323 is 11.85:1 no issues anywhere. 30 is the max timing you want to run on 93. Adjust accordingly.
 

Shakn68

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Thank you all for the tips. I feel better moving forward.
 

Dino Dino Bambino

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Here's another real world NA stroker build in a 2008 Bullitt:

323ci Big Bore Stroker & HCI
C_L_Stroker_323.jpg

Combining a 3.750" stroker crankshaft with the 3.700" cylinder bore of the FRPP Boss Modular 5.0L cast iron block increases displacement to 323ci (5286cc). This stroker combination is similar to the previous 302ci stroker combination apart from the bigger displacement and higher compression ratio.

426.09rwhp 386.90rwtq or 473hp 426lbft (crank)

 

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