to fast over SSR

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steve cowan
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Re: to fast over SSR

Post by steve cowan » Tue Aug 07, 2018 5:56 pm

CGT wrote:
Tue Aug 07, 2018 1:18 pm
mag2555 wrote:
Tue Aug 07, 2018 6:41 am
You will not find much with that ditch cut Exh valve unkess you reverse flow the Exh port. And in the normal flow direction you might see a low lift flow loss!
In a running motor with a ditch cut valve I have seen a very very small low rpm TQ gain,
What did you machine the ditch with, how deep? And how much power did it make or lose? Dyno test? Butt dyno?
*,a mate of mine is machining the exhaust valve for me as i dont have a lathe,i have asked him to come in 0.050'' from the edge of the valve machine down 0.050 '' approx and the hard part will be following the throat angle to the stem.
it might be a complete waste of time but another tool on the shelf to test with and actually see what is does.
my main confusion at the moment is how to form the exhaust port to flow correctly,i see you guys are not concerned with intake / exhaust % ratio to exhaust cam duration and from what i read on ''Special Needs" that was not a factor at all,you had more exhaust ratio and more duration that would of left many people scratching there heads.
it cant be a case of making the port bigger and then saying it has 65% of the intake and then pat it on the head and send it out the door,it cant be that simple surely,
anyway always like "TEAM CREASON" input its always welcome and no you wont upset me with your comments as i have thick skin, aka construction worker :lol:
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Re: to fast over SSR

Post by GARY C » Tue Aug 07, 2018 10:13 pm

If you don't dyno test the stock head velocities vs the ported head velocities how do you correlate the data into anything usable?
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Re: to fast over SSR

Post by steve cowan » Tue Aug 07, 2018 11:57 pm

GARY C wrote:
Tue Aug 07, 2018 10:13 pm
If you don't dyno test the stock head velocities vs the ported head velocities how do you correlate the data into anything usable?
I am assuming the question is for me??
I don't have access to a dyno, if I want to dyno test it's take a number and wait and pay $1000 day, not in my budget, I'm just a guy working in my shed at home trying to learn something.
These heads had velocities over SSR of 480 ft/sec @ 28 " and flow went flat at 500" lift.
Layed SSR down, opened pinch at back of pushrod ft/sec down to 380 and flow pick up from 232 to 241 cfm.
I don't know anyone personally that has flowed a head then bolted to an engine, dynoed, removed heads, ported then reassembled and redyno just to check velocity profile, sorry but I might be missing something with your statement.
My initial intention was to modify these stock 165cc heads to try and make 430-450 hp on my 327 sbc.
So I decided on
Peak power at 6000rpm shift at 6500
I have pinch set at 1.85"
Had 232 cfm at. 500" and port stalled
Velocity was 480 ft/sec
Slow airspeed down to 360-380 and port went to 241 cfm did flatten out at. 600-.700".
I understand what randy is saying about the velocity deal, look at NHRA stock as an example, the ports are totally reconfigured in shape and the velocity is off the chain with airspeed but the Port is not factory shape at all Thanks to epoxy and braze but the runner size is standard, I am way off track here and out of my depth as far as cylinder heads on stockers go,
Gary, not sure if I explained myself correctly and happy to have the discussion
steve c

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Re: to fast over SSR

Post by GARY C » Wed Aug 08, 2018 12:49 am

steve cowan wrote:
Tue Aug 07, 2018 11:57 pm
GARY C wrote:
Tue Aug 07, 2018 10:13 pm
If you don't dyno test the stock head velocities vs the ported head velocities how do you correlate the data into anything usable?
I am assuming the question is for me??
I don't have access to a dyno, if I want to dyno test it's take a number and wait and pay $1000 day, not in my budget, I'm just a guy working in my shed at home trying to learn something.
These heads had velocities over SSR of 480 ft/sec @ 28 " and flow went flat at 500" lift.
Layed SSR down, opened pinch at back of pushrod ft/sec down to 380 and flow pick up from 232 to 241 cfm.
I don't know anyone personally that has flowed a head then bolted to an engine, dynoed, removed heads, ported then reassembled and redyno just to check velocity profile, sorry but I might be missing something with your statement.
My initial intention was to modify these stock 165cc heads to try and make 430-450 hp on my 327 sbc.
So I decided on
Peak power at 6000rpm shift at 6500
I have pinch set at 1.85"
Had 232 cfm at. 500" and port stalled
Velocity was 480 ft/sec
Slow airspeed down to 360-380 and port went to 241 cfm did flatten out at. 600-.700".
I understand what randy is saying about the velocity deal, look at NHRA stock as an example, the ports are totally reconfigured in shape and the velocity is off the chain with airspeed but the Port is not factory shape at all Thanks to epoxy and braze but the runner size is standard, I am way off track here and out of my depth as far as cylinder heads on stockers go,
Gary, not sure if I explained myself correctly and happy to have the discussion
I think the info that Darin Morgan has presented is based off of testing and seems to be good info at least in general terms.

The question is for anyone that wants to share their findings, I was just curious if you were trying to match velocity numbers from a known good port or math equation?

Have you tested them with the pipe pointing up or with a different size pipe and if the flow numbers/velocities change what does that tell you?

I am like you and did not have a budget for testing, even if the dyno time is free the testing is still very expensive but is still necessary to see if what your doing actually works, out of the engines I built, raced and the few I dynoed they all seemed to work well I just didn't have anything to compare them to so there was no way to validate if my work played a factor or how much of a factor.
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Re: to fast over SSR

Post by steve cowan » Wed Aug 08, 2018 4:24 am

GARY,
initially i flowed the exhaust with pipe that was at 90 deg to the port,i will say might of not been a good idea,i have not flowed the dart cast head with downward pipes as i am waiting for new valves and my test valves to come back.
here is some information from Darrin Morgan that will mean something-
EXHAUST PORTS - Exit Area 100% - 105% of the CSA of the valve
Exit Speed - min 300 ft/sec
max 330 ft/sec application specific ????
Exhaust port should be smooth and silent by .400'' - .500'' and upwards
If port pops and crackles blend seat to throat transition may also require chamber work ???
valve shrouding ??????????
the question marks are me asking the questions not quoted by DM

more solid information from Randy 331
biggest factors to consider- RPM/BORE/STROKE/COMPRESSION/VALVE DIAMETER/SEAT ANGLES.
FORGET intake/exhaust % ratio - has nothing to do with cam choice.
EG - ''special needs'' as an example
heads flow 290 cfm
flow 268 cfm with intake on
Exhaust port flow 232 cfm with pipe in/ex ratio is 86.5 %
ex lobe duration was 20 deg bigger than the intake duration (GO FIGURE)
these heads have 50 deg seats

quote Tony Knight
BETTER than 100% VE is from inertia ramming which is contributed by exhaust tuning
but is mostly due to intake runner sizing and cam timing.
unquote

I am going to size the dart cast exhaust port as per DM quote and test on the bench,alot of people have said in the past that an exhaust port can not be optimized on the flow bench using cfm alone.
input welcome
steve c

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Re: to fast over SSR

Post by mag2555 » Wed Aug 08, 2018 6:24 am

In answer to GCT's question on ditch cutting the Exh valves I had rigged up a stand type adapter on the valve grinder to hold a cutter and run like a lathe.
It was slow going , but I got it done.
The cut was .040" deep and .080" wide on a non tulip valve.
The cuts edges where polished out some also.

In terms of power difference two identical sets of head where set up , on with and one without the ditched cut valves.
On back to back days at the track with the weather staying the same, 3 runs made each time the heads with the ditch cut dropped off near 1/10th

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Re: to fast over SSR

Post by randy331 » Wed Aug 08, 2018 9:15 am

steve cowan wrote:
Tue Aug 07, 2018 5:41 pm
just confirm for me- did you go 10.1 @ 130mph in your nova back in 2007 with a 355sbc with 292 cylinder heads done by yourself :shock:

That would be a 355 I did for a guy with a 66 Nova. It has Sportsman 2 heads I did for it. It ran a 10.11 @130 MPH .
I Used 292 heads years ago (early 80s) on a 377 in my Camaro.
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Re: to fast over SSR

Post by 70GS455 » Thu Aug 09, 2018 4:46 pm

This is a little late to the game, but a rougher texture (or dimples, same reason a dimpled golf ball flies farther, a boundary layer is produced, lower Reynolds number) on the SSR only will keep the flow attached longer and may help enough to make the turn better.
Scott

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Re: to fast over SSR

Post by steve cowan » Thu Aug 09, 2018 5:36 pm

Scott,
thanks for your input,yes i have read the threads on rough texture finish as in carbide burr finish
Larry Meaux has posted alot of information and dyno back to back testing on the very subject
what i will say is there are some very respected head porters and engine builders here on speedtalk who smooth the SSR with emery tape at final finish of the intake port.
i read years ago where nascar head porter Phil Martin quoted
there is no wrong opinion as long as you have data to confirm your opinion
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Re: to fast over SSR

Post by FPV_GTp » Mon Aug 13, 2018 4:12 pm

Hi steve cowan , do you have pipemax , if YES , post what do the numbers suggest?

Cheers
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http://speedtalk.com/forum/viewtopic.php?f=31&t=54136&p=758284#p758284

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Re: to fast over SSR

Post by steve cowan » Mon Aug 13, 2018 6:33 pm

FPV_GTp wrote:
Mon Aug 13, 2018 4:12 pm
Hi steve cowan , do you have pipemax , if YES , post what do the numbers suggest?

Cheers
I don't have pipemax, I have engine pro that I bought here a few years ago.
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Re: to fast over SSR

Post by FPV_GTp » Wed Aug 15, 2018 12:46 am

What BHp/RPM level are you chasing for this build of your 327 SBC / 383 SBC ????? cant remember if you mentioned it!

I would strongly recommend getting pipemax and join larry's forum if you haven't already.

Cheers
F/S - CAST IRON FILLER WELDING RODS 5mm X 700mm Ship Australia & New Zealand wide.
http://speedtalk.com/forum/viewtopic.php?f=31&t=54136&p=758284#p758284

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Re: to fast over SSR

Post by steve cowan » Wed Aug 15, 2018 4:49 am

FPV_GTp wrote:
Wed Aug 15, 2018 12:46 am
What BHp/RPM level are you chasing for this build of your 327 SBC / 383 SBC ????? cant remember if you mentioned it!

I would strongly recommend getting pipemax and join larry's forum if you haven't already.

Cheers
I am weighing up my options at the moment,tony knight is doing a intake,exhaust and combustion chamber for me on my 215 pro 1 heads,he is extremely busy and i have not put pressure on him,i am letting the chips fall where they fall.for me to really get after it to make the car run well i would need a 4.5 rear gear,trans brake would be nice as well.
i have finished the 165cc cast dart head,i have another one coming from Summit so i can copy and have a pair,the 383 bottom end is fresh hone,rings, bearings,balance etc,i have a few different flat tappet cams and roller cams as well to try,i also have a set of stock dart sportsman 2s as well,
i bought the cast 165cc heads to learn on and see where it goes,i have been bolting engine parts together now for a while and its time to start trying to work out what works with what.
that means i can still run the 4.1 rear gear and i will still use the big converter but i have a spare 9'' 4000rpm converter as well.
the 327 is just a junk engine,i threw it together with spare parts,bad ring seal etc,not worth doing anything with it.it ran 110mph @ 3550 pounds and actually drove pretty good and puked very little oil.
as far as pipemax, yes i agree i will purchase in the near future,Larry is so generous with the information he shares,i have been reading all of his threads and post back from the start of speedtalk,for me at my level of experience i really have to be careful of information overload.
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Re: to fast over SSR

Post by randy331 » Fri Sep 28, 2018 9:22 pm

GARY C wrote:
Tue Aug 07, 2018 10:13 pm
If you don't dyno test the stock head velocities vs the ported head velocities how do you correlate the data into anything usable?
The same would go for anything else you see on a flow bench.
How would you change velocities without changing anything else ? CFM/CSA/shape etc.

That's part of the challenge of making changes, trying to decide what did what.
If you grind on a port and it flowz more, and ran better,... was it the flowz ?
I mean if you ground on it, it's bigger too, so maybe it's the larger CSA that made any difference ?
But,.. over time some trends start to show up.

Randy

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Re: to fast over SSR

Post by GARY C » Sat Sep 29, 2018 2:41 pm

randy331 wrote:
Fri Sep 28, 2018 9:22 pm
GARY C wrote:
Tue Aug 07, 2018 10:13 pm
If you don't dyno test the stock head velocities vs the ported head velocities how do you correlate the data into anything usable?
The same would go for anything else you see on a flow bench.
How would you change velocities without changing anything else ? CFM/CSA/shape etc.

That's part of the challenge of making changes, trying to decide what did what.
If you grind on a port and it flowz more, and ran better,... was it the flowz ?
I mean if you ground on it, it's bigger too, so maybe it's the larger CSA that made any difference ?
But,.. over time some trends start to show up.

Randy
Yes the more versions you test, the more data you have to understand your trends.

You find what shape works with what CSA regardless of CFM. Same with Bowl, SSR, Combustion chamber and Seat.
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