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DSS 427 SB Ford build

General engine tech -- Drag Racing to Circle Track

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RevTheory
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Re: DSS 427 SB Ford build

Post by RevTheory » Sun Apr 03, 2016 2:29 pm

David, as I've gotten older, I'm of the opinion that a true street "hot rod" still needs to be somewhere around 12 inches of manifold vacuum regardless of output and rpm. Below that and I just want out of the damn car after cruising for an hour. I also realize that's an opinion that may not be so popular around here.

Any estimates of where you may be sitting in that regard? I'm guessing a larger exhaust split will drop your vacuum even further.

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Re: DSS 427 SB Ford build

Post by David Vizard » Sun Apr 03, 2016 3:26 pm

RevTheory wrote:David, as I've gotten older, I'm of the opinion that a true street "hot rod" still needs to be somewhere around 12 inches of manifold vacuum regardless of output and rpm. Below that and I just want out of the damn car after cruising for an hour. I also realize that's an opinion that may not be so popular around here.

Any estimates of where you may be sitting in that regard? I'm guessing a larger exhaust split will drop your vacuum even further.
ABOUT 12 INCHES - I GUESS WE ARE BOTH AGING GRACEFULLY!
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Re: DSS 427 SB Ford build

Post by MadBill » Sun Apr 03, 2016 6:08 pm

Since I'm in the process of slowly assembling a barely-streetable (2 x 4, 270°/273° 0.723"/0.700" Jones SR, etc.) 'max power, ignore everything else' 496 c.i. for my Camaro, I'm amazed to see these words flowing off my keyboard, but: RevTheory has it right. It's far more instructive, useful and challenging to come up with a well-mannered package that still makes a ton of power than to build a no compromises, all-out race engine and stick it in some poor guy's street ride.
Oh, one suggestion: Race gas is obviously impractical, but unless you're in the habit of lending your ride to idiot friends who thoughtfully tank it up with the cheapest gas they can find, why not build for 91 Octane, mostly to bump up the low speed torque and maybe allow a tad more duration without driveability penalties?
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Re: DSS 427 SB Ford build

Post by 427dart » Sun Apr 03, 2016 7:38 pm

Well my 427 build runs very well on the street and has 13-14 inch of vac. Has run in the 10's at 132 with it's mild 3.50 gear. So how far from what is considered optimum is my cam pick which is a Lunati 61013 hyd. roller cam with 242/249 duration on a 112 LCA with .600 lift? Intake valve opens 13 degrees BTD. Cranking compression is 195-200 checked after 5 yrs of use.

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Re: DSS 427 SB Ford build

Post by Walter R. Malik » Sun Apr 03, 2016 8:53 pm

I have a rather strong opinion on this because I really live it, every summer.
No matter what is in the vehicle or engine, a REAL street hot rod NEEDS to be "fun to drive"; not work. It needs to be something you just can't wait to get behind the wheel a go for a 4 hour cruise both highway and city type streets or it just is not worth a "hill of beans" to any real street hot rod enthusiast.

That does not mean it just HAS TO BE an automatic as standard shift vehicles can be "fun to drive" also; only if they are not quirky and the driver can't be lazy.
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Re: DSS 427 SB Ford build

Post by David Vizard » Sun Apr 03, 2016 8:57 pm

Walter R. Malik wrote:I have a rather strong opinion on this because I really live it, every summer.
No matter what is in the vehicle or engine, a REAL street hot rod NEEDS to be "fun to drive"; not work. It needs to be something you just can't wait to get behind the wheel a go for a 4 hour cruise both highway and city type streets or it just is not worth a "hill of beans" to any real street hot rod enthusiast.

That does not mean it just HAS TO BE an automatic as standard shift vehicles can be "fun to drive" also; only if they are not quirky and the driver can't be lazy.
!0-4 my sentiments exactly.
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Re: DSS 427 SB Ford build

Post by MadBill » Sun Apr 03, 2016 9:44 pm

427dart wrote:Well my 427 build runs very well on the street and has 13-14 inch of vac. Has run in the 10's at 132 with it's mild 3.50 gear. So how far from what is considered optimum is my cam pick which is a Lunati 61013 hyd. roller cam with 242/249 duration on a 112 LCA with .600 lift? Intake valve opens 13 degrees BTD. Cranking compression is 195-200 checked after 5 yrs of use.
Sounds ideal dart! What are you using for fuel and CR? Must be close to 11.0:1?
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Re: DSS 427 SB Ford build

Post by 289nate » Mon Apr 04, 2016 1:37 am

Please build if for low end torque. I would hate for the mainstream to figure out the advantage of gearing for a higher rpm power band and how it affects torque at the tire. Cruise on the highway? Oh, I have an overdrive transmission like so many others have in their old muscle cars today. :D Problem is most of those street strip guys are still bragging to me about their flywheel peak torque instead of concentrating on what makes a vehicle accelerate. Low end torque for the book please!!!

If I personally wanted lowend torque and didn't have an overdrive transmission, I'd pull a sound mid to high mileage stock 5.0L Ford to 5.3L LSx from the junk yard and throw a mediocre turbo kit at it. No overdrive needed and torque for days. Kind of like my turbo diesel dirty max with tow beast 66x lb-ft of torque which would lose to the 400'ish lb-ft torque LSx SUV in the same weight vehicle with the proper gearing.

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Re: DSS 427 SB Ford build

Post by 289nate » Mon Apr 04, 2016 2:00 am

7,500'ish rpm shift point piss poor little .060 over 289 torque challenged too big of induction pump gas junk on the street. Throttle response? Got to 2:20 in the video where I give it a half throttle stab from low rpm in second gear. Having a little fun before I drive it to the track early that afternoon. https://www.youtube.com/watch?v=cUqM4DPgaBg

Highway? Throw it into 5th and almost fall asleep on the way to Irwindale. https://www.youtube.com/watch?v=hbAmrVzQ2tM

An 1/8 mile pass that night. https://www.youtube.com/watch?v=bZVL3E4baYE

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Re: DSS 427 SB Ford build

Post by Calypso » Mon Apr 04, 2016 2:36 am

MadBill wrote:Since I'm in the process of slowly assembling a barely-streetable (2 x 4, 270°/273° 0.723"/0.700" Jones SR, etc.) 'max power, ignore everything else' 496 c.i. for my Camaro, I'm amazed to see these words flowing off my keyboard, but: RevTheory has it right. It's far more instructive, useful and challenging to come up with a well-mannered package that still makes a ton of power than to build a no compromises, all-out race engine and stick it in some poor guy's street ride.
Oh, one suggestion: Race gas is obviously impractical, but unless you're in the habit of lending your ride to idiot friends who thoughtfully tank it up with the cheapest gas they can find, why not build for 91 Octane, mostly to bump up the low speed torque and maybe allow a tad more duration without driveability penalties?
Driving a car like the Camaro you're building is like eating very sweet cake. It's just delicious occasionally, but you'll feel sick if you do it everyday. :)
That's why you have to have another one that is actually enjoyable to drive, so you don't need to compromise too much. Just need to stay focused on the target building the enjoyable one, not to fall into same trap again. :D

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Re: DSS 427 SB Ford build

Post by 289nate » Mon Apr 04, 2016 3:04 am

David Vizard wrote:
Walter R. Malik wrote:I have a rather strong opinion on this because I really live it, every summer.
No matter what is in the vehicle or engine, a REAL street hot rod NEEDS to be "fun to drive"; not work. It needs to be something you just can't wait to get behind the wheel a go for a 4 hour cruise both highway and city type streets or it just is not worth a "hill of beans" to any real street hot rod enthusiast.

That does not mean it just HAS TO BE an automatic as standard shift vehicles can be "fun to drive" also; only if they are not quirky and the driver can't be lazy.
!0-4 my sentiments exactly.
DV
FOUR hour trip? Max performance in ANY rpm range should never come into this equation. You need max fuel economy.

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Re: DSS 427 SB Ford build

Post by 289nate » Mon Apr 04, 2016 3:11 am

This site should be called adjustable seat, seat warmer, and air conditioning talk. Speed talk? LOL! I'll pay money for David's book to show me how they are making early model 8.2" deck Fords live at 600 HP. Show me your great grandmother friendly hot rod that is supposed to scoot. Nah, I'm here to talk speed.

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Re: DSS 427 SB Ford build

Post by RevTheory » Mon Apr 04, 2016 8:36 am

And now back to our regularly scheduled program...

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Re: DSS 427 SB Ford build

Post by David Vizard » Mon Apr 04, 2016 8:58 am

RevTheory wrote:And now back to our regularly scheduled program...
Jeez i had to chuckle over this ------

Well the cam decision might well be made today. Expect Chris to call later so will post cam selection.

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Re: DSS 427 SB Ford build

Post by groberts101 » Mon Apr 04, 2016 9:44 am

Given the prerequisites you initially posted.. and the size of those 205 ports in relation to a 427 cid "street motor".. I don't see why Chris would be pushing for those bigger topend numbers that you mentioned. If they'll also be heavily ported to better mitigate the higher rpm airspeed?.. then hell yes!.. go big and gear it to suit the higher powerband and just deal with the higher idle speed needed to help improve manifold vacuum.

Otherwise, I'd say come up with a happy medium and build the thing to hit peak torque somewhere in the 4,400-4,800 rpm range and you'll have a best of both worlds type deal that a wider cross section of average Joe's would love to have in their own hotrod/streetrod. It'll idle well enough for most at around 850 rpm.. still rev to 7,000.. and you'll also need slicks to fully hook it up! :mrgreen:

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