Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

General engine tech -- Drag Racing to Circle Track

Moderator: Team

User avatar
MadBill
Guru
Guru
Posts: 15024
Joined: Tue Nov 15, 2005 10:41 am
Location: The Great White North

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by MadBill »

Carnut1 wrote: Thu Mar 15, 2018 8:00 pm I should add that was at .8" lift they flowed 357@ .7" lift and a surprising 286 cfm backwards at 28".
The merit in evaluating reverse flow at overlap-range lifts is clear, but what purpose is served by doing so at more than say 0.250"? :?
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.
Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by Carnut1 »

MadBill wrote: Thu Mar 15, 2018 10:12 pm
Carnut1 wrote: Thu Mar 15, 2018 8:00 pm I should add that was at .8" lift they flowed 357@ .7" lift and a surprising 286 cfm backwards at 28".
The merit in evaluating reverse flow at overlap-range lifts is clear, but what purpose is served by doing so at more than say 0.250"? :?
This was suggested by more than one pro in past threads. I was actually expecting this port to flow much more in reverse than it did. Thanks, Charlie
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
statsystems
Guru
Guru
Posts: 1508
Joined: Sun Apr 03, 2016 1:17 am
Location:

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by statsystems »

MadBill wrote: Thu Mar 15, 2018 10:12 pm
Carnut1 wrote: Thu Mar 15, 2018 8:00 pm I should add that was at .8" lift they flowed 357@ .7" lift and a surprising 286 cfm backwards at 28".
The merit in evaluating reverse flow at overlap-range lifts is clear, but what purpose is served by doing so at more than say 0.250"? :?
I can't really pin point it Bill because I no longer have the flow sheets I had when testing (should have kept them when I sold the bench) but it seems to me that any time I lowered reverse flow anywhere in the curve, even if it lost flow the port was always more stable.

I wish I had spent more time developing why it was, but I knew it made more HP, and at that time that was all that concerned me.
User avatar
MadBill
Guru
Guru
Posts: 15024
Joined: Tue Nov 15, 2005 10:41 am
Location: The Great White North

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by MadBill »

Interesting, and non-intuitive... :-k
Felix, qui potuit rerum cognscere causas.

Happy is he who can discover the cause of things.
Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by Carnut1 »

0316181921.jpg
Dart 215 tech sheet.
You do not have the required permissions to view the files attached to this post.
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by Carnut1 »

0311181226a.jpg
Been thinking of polishing out the radius under the 45 seat. Input welcome. Thanks, Charlie
You do not have the required permissions to view the files attached to this post.
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by Carnut1 »

MadBill wrote: Thu Mar 15, 2018 10:12 pm
Carnut1 wrote: Thu Mar 15, 2018 8:00 pm I should add that was at .8" lift they flowed 357@ .7" lift and a surprising 286 cfm backwards at 28".
The merit in evaluating reverse flow at overlap-range lifts is clear, but what purpose is served by doing so at more than say 0.250"? :?
MadBill got me thinking... Would a reverse flow, cfm - port energy curve be worth a look? I am thinking it could be a real help. Not sure if it has been done before. If there is some interest I will get it done this weekend. Thanks, Charlie
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
groberts101
Guru
Guru
Posts: 1980
Joined: Sat Mar 08, 2008 3:08 pm
Location: Minneapolis

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by groberts101 »

Hi again, Charlie. Don't have much input on the flow and physics related to the task at hand here.. but I did want to take the time to commend you on your much improved porting quality as of late. That old saying "practice makes perfect" seems to be very true when it comes to shaping and carving metal.

I remember thinking the first set of heads I had done "professionally" looked downright horrible as if they'd been done by a blind man missing a few fingers but just passed it off as shape and size being the most important anyways. That.. and the price(GULP).. are what made me start doing my own from there onwards. Surprising how a few extra preloaded grinders or bit changes and another 30 minutes per set usually achieves that last bit of quality. Good looking stuff coming off your bench lately. =D>
Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by Carnut1 »

groberts101 wrote: Sat Mar 17, 2018 12:15 pm Hi again, Charlie. Don't have much input on the flow and physics related to the task at hand here.. but I did want to take the time to commend you on your much improved porting quality as of late. That old saying "practice makes perfect" seems to be very true when it comes to shaping and carving metal.

I remember thinking the first set of heads I had done "professionally" looked downright horrible as if they'd been done by a blind man missing a few fingers but just passed it off as shape and size being the most important anyways. That.. and the price(GULP).. are what made me start doing my own from there onwards. Surprising how a few extra preloaded grinders or bit changes and another 30 minutes per set usually achieves that last bit of quality. Good looking stuff coming off your bench lately. =D>
Thanks! I would like to add, these are just pics from development. I spent zero time finessing these to make them pretty.
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
Carnut1
Guru
Guru
Posts: 4659
Joined: Tue Jun 11, 2013 6:32 pm
Location: Melbourne fl.

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by Carnut1 »

0317181954h.jpg[attachment=1]0317181954h.jpg
Roughing a fresh intake and the weapon of choice, Buckeye carbide 1/2" oval 45 degree helix. I bought this one at PRI, I also bought a 5/8" but it is just savage. This is a good mix of fast metal removal and a usable rough surface texture. Thanks, Charlie
You do not have the required permissions to view the files attached to this post.
Servedio Cylinder Head Development
631-816-4911
9:00am - 9:00pm EST
randy331
Guru
Guru
Posts: 3337
Joined: Mon Dec 04, 2006 7:30 pm
Location: N.W. MO.

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by randy331 »

You can only learn so much chasing cfm or port energy around on a flow bench. At some point you need other data, like dyno and/or track info. And it's likely you have figured out the shapes that flow good.

And I also think your grinding skills are good.

I just dynoed a 468 cube BBC with a set of 781 casting heads I did some porting on. The math on the csa says it'd peak at 6800-7000 but it was way short on cfm when figuring cfm demand for that cube/rpm. But it peaked right in that rpm range.

CFM only tells you so much.

Randy
user-9274568

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by user-9274568 »

My .02 is min CSA does NOT set the peak RPM.
User avatar
midnightbluS10
Expert
Expert
Posts: 933
Joined: Sun Oct 20, 2013 8:41 am
Location: Shreveport, LA

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by midnightbluS10 »

groberts101 wrote: Sat Mar 17, 2018 12:15 pm Hi again, Charlie. Don't have much input on the flow and physics related to the task at hand here.. but I did want to take the time to commend you on your much improved porting quality as of late. That old saying "practice makes perfect" seems to be very true when it comes to shaping and carving metal.

I remember thinking the first set of heads I had done "professionally" looked downright horrible as if they'd been done by a blind man missing a few fingers but just passed it off as shape and size being the most important anyways. That.. and the price(GULP).. are what made me start doing my own from there onwards. Surprising how a few extra preloaded grinders or bit changes and another 30 minutes per set usually achieves that last bit of quality. Good looking stuff coming off your bench lately. =D>
I was taught early on, as a child, that practice doesn't make perfect. Practice makes permanent, and not from personal experience. If you're not doing it right to begin with, how do you perfect it? If you're practicing the wrong way/thing or your methods are flawed, you're not going to get perfect no matter how much you practice. Not saying this is the case currently. Just that I don't use that saying anymore and when I hear it, it makes one wonder just exactly how and what they're practicing. It might not be perfect, but it'll be permanent whether right or wrong.
JC -

bigjoe1 wrote:By the way, I had a long talk with Harold(Brookshire) last year at the PRI show. We met at the airport and he told me everything he knew about everything.It was a nice visit. JOE SHERMAN RACING
User avatar
Stan Weiss
Vendor
Posts: 4801
Joined: Tue Feb 20, 2007 1:31 pm
Location: Philadelphia, PA
Contact:

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by Stan Weiss »

randy331 wrote: Sat Mar 17, 2018 11:14 pm You can only learn so much chasing cfm or port energy around on a flow bench. At some point you need other data, like dyno and/or track info. And it's likely you have figured out the shapes that flow good.

And I also think your grinding skills are good.

I just dynoed a 468 cube BBC with a set of 781 casting heads I did some porting on. The math on the csa says it'd peak at 6800-7000 but it was way short on cfm when figuring cfm demand for that cube/rpm. But it peaked right in that rpm range.

CFM only tells you so much.

Randy
Randy,
So just what CSA did you use?

Stan
Stan Weiss/World Wide Enterprises
Offering Performance Software Since 1987
http://www.magneticlynx.com/carfor/carfor.htm
David Vizard & Stan Weiss' IOP / Flow / Induction Optimization Software
http://www.magneticlynx.com/DV
statsystems
Guru
Guru
Posts: 1508
Joined: Sun Apr 03, 2016 1:17 am
Location:

Re: Ported Dart 215 pro1 platinum with port energy discussion 2.0

Post by statsystems »

Carnut1 wrote: Sat Mar 17, 2018 11:50 am
MadBill wrote: Thu Mar 15, 2018 10:12 pm
Carnut1 wrote: Thu Mar 15, 2018 8:00 pm I should add that was at .8" lift they flowed 357@ .7" lift and a surprising 286 cfm backwards at 28".
The merit in evaluating reverse flow at overlap-range lifts is clear, but what purpose is served by doing so at more than say 0.250"? :?
MadBill got me thinking... Would a reverse flow, cfm - port energy curve be worth a look? I am thinking it could be a real help. Not sure if it has been done before. If there is some interest I will get it done this weekend. Thanks, Charlie


Anything you can test, measure and quantify is worthy of doing. Like Randy said, you need to verify the end result with dyno and track results.


I used to say you can never have enough data, and most times that's true. There is a point where you end up in mental masturbation and overload.
Locked