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Discussion Starter · #1 ·
Good evening FFR community-

I just published a video which walks through how to select the right engine for your MK4 build. The (2) high level paths detailed in the video include...

* Purchasing a completed crate engine
or
* Rebuild a salvage yard engine

Check it out and let me know what you think!

-Tacojoe

 

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Great summary Joe. I can't disagree with any of the points you made. Thanks
 

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I liked the video, thought it was well done. Only disagreement would be the HP suggestions. I think the limits on HP is more on how you apply the skinny pedal rather than the actual rating. But as they say YMMV.
Jim
 

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Discussion Starter · #5 ·
Thanks much gents- appreciate the feedback. For the SBF engine I'm building now, I'm completely on the fence if I stroke it to 347 or just keep the OEM crank because I've been so impressed with the little 302 in there already! Any 347 owners out there and thoughts on 400-450hp? I think Jim might be right here - its all about how hard you mash the skinny pedal at the stoplight (lol) :)
 

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When I had my car built the original engine was a stock 302 and after we sorted "most" of the initial build gremlins I swapped it out to a 347 with stack injection. The stacks never really got dialed in and we installed a carb and the engine ran well. I ran that engine for a couple years but it always seemed to need a bit more so I swapped in a built 408 (521 hp to the wheels) and traction became a real issue, but a good problem to have with adequate throttle control . . . LOL Moral of the story . . . I highly recommend going to the 347 instead of stock 302, you will appreciate the extra torque.
 

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I'll add that having a linear throttle linkage and longer pedal movement makes a huge difference. This enhances the ability to modulate the throttle and minimizes the quirky instantaneous acceleration.

I never had any trouble caused by the mechanical properties of my previous cars, both with the same motor that will go in my Challenge car. Now trouble caused by the operator is a whole different story.

427w, 440hp/435tqe at the wheels. It was great to drive. Will be again.

Jim
 

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I'm completely on the fence if I stroke it to 347 or just keep the OEM crank because I've been so impressed with the little 302 in there already! Any 347 owners out there and thoughts on 400-450hp?
I'm the insolent one who commented on the gt40 heads on the youtubes. Regardless in my opinion of building and racing my own pushrod ford's I would not waste any time on a stock block 302. Hear me out: if you want the bang for the buck an efi 302 will give you but you don't want to spend dart/motorsport block money I wouldn't consider anything but a stock crank or a cast 3.4" (347) $280 crank. The reason is the inconvenient truth you will break that block before you break that crank. It's not glamorous to buy a cast stroker crankshaft in today's world, but it does provide great value in an otherwise structurally inadequate platform. Don't confuse what I'm saying that I think anybody really needs a dark block for their fun car because you don't. A regular old production EFI 302 and a cast stroker crank will generate a lot of smiles per gallon. I know in your particular case you're not considering forced induction so let's not worry about things we're not going to do.

And this is coming from someone who has a 331 in a car that I built. It costs more money to make less power with very little upside. The 0.075" of crank throw is negliable in the grand scheme of things. I know this fires people up about compression height and sleeve length in the aforementioned blocks. That said I challenge naysayers to build a modern engine that isn't 50 years old. There are no 1.6" tall pistons in anything anymore. The ls7 that eats your lunch has a warranty and a 1.17 ch. I just cannot understand the fixation on these things. For my next trick I'll say peak piston speed doesn't matter nor does rodv/stroke ratio. As long as it doesn't blow up the bigger motor makes more power on the dyno every single time. We are not building f1 motors, we are building the equal of 1950s garbage tractor engines. We could all agree if we could frame what we are trying to do with honesty.

Ps I really like that you painted your roadster yourself. Im not ready for paint but I really feel like you have beaten me in car guy life. I could do it , I just don't want to. I think you captured the spirit of "build your own car".
 

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@phils88gt makes a bunch of good points. I too went from 302 to 331 (love the torque) and if I had known then what I know now it would have been a 347. That being said, I see a 408 in my future. RPM (within reason, I'm not talking F1 or modern sport bike levels) is fairly independent of rod ratio, and even displacement (Richard Holdner has some great dyno results that speak to this). Valve control is the pushrod engines Achilles heal.
@TacoJoe , Nice video! I think we all have our HP goals and usage goals (and $$ available) that guide out engine choices. I know the more I drive the car, the more power I think it needs 😁.
 

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I too went from 302 to 331 (love the torque) and if I had known then what I know now it would have been a 347. That being said, I see a 408 in my future.
My ffr has a 393 Windsor in it. Not because there is any reason to do it, but I had the heads, rods, pistons, rings, and pins, already. It kept my cost low. Today I would have done a 408 or 427 or a new 7.3 gas.

You are indeed right that valve control is the key but you can get by below 6500 with some pretty lame stuff that is cheap and it works. I just don't know what Joe really wants; let's hope he replies so we can help spend his money.
 

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Started with 302, GT40 heads and vortec with low pressure. stock efi. Wound up with 347,9.7 compression, Vic Jr heads, vic jr single plane intake and very close to dirt track cam (love the lope). Dyno # 472/460 they said. Mechanical lionkage much better. Beyond my hope for performance. The TKX just installed, blew up a worked over T5 after 8 years. Very quick. I understand a 408 is very good but weighs more only drawback.
 

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Stock block 302 is good for what, 450 HP max before you need to worry?

Airflow is everything. Get the best heads you can afford and match cam choice, headers, intake and induction. I would look for a system that makes peak HP at less than 6,500 for the street. The more CU. IN., the more torque available. All pretty basic stuff and there are crate engine providers out there that will dial in your choices so you don't have to guess.
 
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