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Opinions on my street 427 Windsor dyno results?

Posted: Sun Jun 28, 2020 8:59 pm
by 427dart
Been a while since I was able to log on here and glad to be back.
Can't recall whether I had posted the results of a Dynojet test on my 427 Windsor setup from a year or so ago but would like to see what some of you think.
I built this Dart blocked engine back in 2010 and it still runs strong no smoke or leaks. Seems to be a strong runner in my 2950 lb. Mustang LX with
3.50 geared 9 incher and a TKO-600 trans. I LOVE the torque!
Compression is 10.3 and the camshaft is 241/249 @ .050 with .600 lift all around. 112 LCA.
Heads TFS High Port 225 with Int. CFM 331 and Exh CFM 258 @ .600 lift
Intake Manifold is a PME dual Holley 180 degree type manifold with a pair of 650 CFM Holley carbs.
Headers are Kooks 1 7/8 with 3 inch collector and 3 inch X pipe to 3 inch mufflers with 2 1/2 tailpipe.

Yes I know this intake could be limiting some top end power compared to the Edelbrock Super Victor with the single 850 carb that I used to run.
But would you think the cam and intake are topping out at about same RPM?

Re: Opinions on my street 427 Windsor dyno results?

Posted: Sun Jun 28, 2020 10:32 pm
by travis
That is a beautiful torque curve! I bet it’s a rocket in such a light car.

Re: Opinions on my street 427 Windsor dyno results?

Posted: Sun Jun 28, 2020 10:44 pm
by Steve.k
Very nice power. And you dont have to rev it hard at all. I’d be very happy with that.

Re: Opinions on my street 427 Windsor dyno results?

Posted: Sun Jun 28, 2020 11:21 pm
by 68fastback
Love the look 427dart, looks like an old FE. Perfect!

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 12:20 am
by MadBill
Great torque, but with those parts (although I'm not familiar with the PME) I'd expect ~500 RPM more at the peak...

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 2:06 am
by F-BIRD'88
If you want to really know what it is doing run it down the track a few times . The MPH tells the tale . (record the track weather data too)
Those chassis dyno tests are really only intended and valid for if testing and making CHANGES , Then retesting..
A-B testing for +/- Power improvments.

If you are curious if the big racing intake and big carb makes more power reinstall it and retest it.

With no other qualifing test info, (weather dyno correction factor etc etc) the one chassis dyno sheet looks fine. . Now make a change and run it again.

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 3:34 am
by F-BIRD'88
Image
There ya go new lower price.. get busy
#300-243

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 6:10 am
by mag2555
Real nice wide Torque band, but with what that motor has for heads and Cam I would think it would be cracking the 500 hp mark!

I would think about changing over to a single plane Intake with even just a 750 cfm Carb if you want HP numbers above where your are now.

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 6:46 am
by F-BIRD'88
This is a chassis dyno test (in car) not a brake dyno test.
(Engine itself on a engine dyno with no/few drive accessories , a Specific rpm acceleration rate and corrected to sae standard air. Not the same thingie.

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 9:12 am
by Steve.k
Is pme price Motorsports? Im impressed by exh flow on heads. Not used to that in Clevelands.

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 9:47 am
by 427dart
I must mention that this dyno run was at a local large car show in late summer and of course temps in high 80's and 55% Humidity.....typical Central Va. weather. The carb setup was a pair of 1850 series 600 Holley carbs with the addition of 650 1 11/16 throttle plates.
Now I'm running the same 650 Holley VS in front carb position with the White spring. The rear secondary carb is a 4224 Holley 660 that I transferred the
metering blocks and "tune" from the old 650 that was back there.
I have the linkage staged so that I cruise on the front carb until about 40% throttle travel. After that the linkage pulls in the rear 660 with it's secondary coming in really quick the way the 660's are setup with the Center Squirter. From my video testing the front carb vac. secondary is kicking in as everything is opening up.
The 427 loves it with a huge acceleration blast that is smooth and hard!
I run Nitto soft compound Competition tires all around and they are 9 inch tread and it allows strong acceleration while they are breaking loose from 3500 RPM up thru 6000 RPM in 2nd gear roll at speed and into 3rd gear.
I ran easy 10.88 @ 131.8 several years ago with same 3.50 gear but with the 850 Holley and Super Vic intake just playing with it....easy launch and shifting.
Love the dual Holley setup I built for it and at age 66 it is enough for me today on the streets.

Wish the intake was a bit taller with larger runners but still dual plane but PME designed it for the guys with Cobra builds and for mid range type 351 and 427 stroker engines. When I got the manifold I opened it up and smoothed and blended transition areas enlarging the runners as best as I could reach. Opened up the 8 throttle bore plenums to 1.700 diameter for the larger 650 throttle plates. 1.500 inch tall 4 hole spacers sit under the carbs for
more plenum area. Custom made large oval air filter assembly seals to the 4 inch cowl hood.

Thanks for your comments!

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 10:00 am
by 427dart
Steve.k wrote: Mon Jun 29, 2020 9:12 am Is pme price Motorsports? Im impressed by exh flow on heads. Not used to that in Clevelands.
Yes... Price Motorsport Engineering. He told me he had a version of the 427 Tunnel Wedge intake for the 351W on prints but has not as yet brought it to casting. That would be an interesting intake on my setup.
I have looked at the new Holley Hi Ram intake and have seen dyno test on engines like mine but for the cost of all involved and changes needed
to the hood...it is tall... decided to keep what I have when looking at the power gain and torque loss where I spend most time.

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 11:49 am
by Steve.k
Very cool setup. Is that a 83 mustang? I like that body style the best.

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 1:29 pm
by 427dart
Steve.k wrote: Mon Jun 29, 2020 11:49 am Very cool setup. Is that a 83 mustang? I like that body style the best.
It is a 1985 LX. I ordered it as a 5.0 HO with the 5spd. with dealer installed 3.73 gears back in late April 1985.
Always a project car and never driven in bad weather or Winter car has 26,000 miles on it and was in several Mustang magazines in the 90's
while running with it's original 302 engine. Got it in the 12.60's at 108-109 MPH back then with the little factory 585 Holley carb!

Re: Opinions on my street 427 Windsor dyno results?

Posted: Mon Jun 29, 2020 8:05 pm
by 68fastback
Take it down the track with this setup and let us know how it goes, it would be interesting to see the difference in MPH.


That is a great looking car and it's got to be a blast to drive..