P.P.W9's and the goal of more HP

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RAMM

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Well this is going to be interesting for me as I don't often get the chance to work on W9's.

The two P's in the title stand for P reviously P orted in case anyone was wondering.

I had a great customer and FABO member send me his W2's and he travels in a fairly serious circle of drag strip guys out his way, and next thing you know a guy he knows sends me these lightweight beauties to work on. The mandate is to find more power for the guy so that is what the focus is on. The car is drag 'Cuda with a hi-compression 416 on alcohol with a .700" roller so it doesn't really compromise on anything which should make my job a little simpler. I understand it already runs pretty deep into the 9's @ 135+mph so I really don't want to muck this up.

Initial inspection tells me that the port work looks pretty good. The intake valve combination is 2.15"/1.60" 3/8" stem which kinda surprised me--heavy @ 5.420-5.430 OAL. The throats measure right @ 90% -1.935" . The only thing I'm wondering is if the intake valve is a little too big for the 4.07" bore @ almost 53%. Usually anything over 51.5% or so on an inline begins to negatively impact power which is probably due to excessive shrouding, I guess.

So after removing the springs which are pretty serious with 273lbs @ 2.00 704lbs @ 1.300" I washed em up and picked a port and flow tested it. On a 4.06" bore @ 28" H20 they went:

.100 66.5
.200 133
.300 189.1
.400 241.7
.500 287
.600 314.4
.700 327.5
.750 323.5
.800 315.5

They actually peaked @ 330.5 @ .735"

I thought this was pretty good to be honest and with his .700" SR cam it is probably accessing an awful lot of that 330 ish cfm. More to follow in a moment. J.Rob

ASRECVDCHAMBER.jpg


PRELIMFLOWTEST.jpg
 
I looked through my valve stock and found a set of Ferrea's in the following sizes--2.100" 1.60" 11/32" stem 5.450".
I liked these immediately for the weight reduction in the stem size, the better bore to valve diameter ratio 51.5% the throat now creeps up to favour higher lifts @ 92% and it allows me to remove less to get the bowl to the size and shape I want it. The bowl on these seem to be where some nice gains can be had. Again though, whoever did them did a really nice job. Yes I did flow them just to see if this was a road worth going down. Flow test as follows:

.100 65.5
.200 126
.300 188
.400 240.1
.500 288
.600 322.4
.700 333.5
.750 321
.800 313

Actual peak was 335 @ .730".

I think a crisp valve job, some nice bowl shaping and some texturing may pick these heads up quite a bit more. I will measure far more tomorrow. J.Rob

SMVALVECHAMBER.jpg
 
Frankly, a W9 stroker with lots of squeeze, alky, and a roller should be capable of way more than 135.
My W5’s went that on super stock springs, gas, at 3350 pounds, and it was far from maxed, next owner spruced it up and went 140 mph on still race gas.
W9 has a ton more potential easily
 
Vary nice. excited to see the progress.
One question.
Is the quench pad, opposite of the spark plug, Flat? Or is there a small taper towards the valves.
 
RAMM said:
Flat, optical illusion. J.Rob
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I picked up some W9’s in the spring and as soon as I get my 360 magnum off the dyno I will be starting on my W9 416 so I look forward to following this one
 
Not disparaging your work, at all, but it'd be a tough spot to be in. The heads already flow well...so picking up gains that will show up on the strip won't be easy.


Then, there are already guys who have well sorted cnc programs for the W9 that will push them up around 365 CFM.
 
gregcon said:
Not disparaging your work, at all, but it'd be a tough spot to be in. The heads already flow well...so picking up gains that will show up on the strip won't be easy.


Then, there are already guys who have well sorted cnc programs for the W9 that will push them up around 365 CFM.
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I think some of port programs take the W9s out over 400cfm
 
gregcon said:
Not disparaging your work, at all, but it'd be a tough spot to be in. The heads already flow well...so picking up gains that will show up on the strip won't be easy.


Then, there are already guys who have well sorted cnc programs for the W9 that will push them up around 365 CFM.
Click to expand...

Last set I had here peaked at 363 cfm.

Agree about no easy gains to be realized here , at least gains that show up on the strip like you said. I'm slowly formulating a plan. J.Rob
 
I would keep the 2.150 valve diameter and use a 50 or 52 degree seat on both the intake and exhaust and not worry about the flow number so much.

54% for an in-line head that opens on the centerline of the bore should be fine.

The fact that it liked the smaller valve says it wants a steeper seat. Depending on RPM, I wouldn’t count out a 55 degree seat.

Obviously, that valve is long enough with enough diameter that he needs 5/16 stems or better yet, Ti intakes.
 
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There are guys pushing over 900HP out of W9 headed engine now....that's naturally aspirated.

My engine will use a 2.15 valve on a 4.07 bore. That's not by choice, but it's not bothering me either.
 
RAMM said:
Ive heard about 400cfm W9,s but never had them in my hands or on my dyno. Would like to see some for sure. J.Rob
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My friend has some W8’s that go 420cfm...and claims the 9’s might go more
 
I don't run alcohol so someone correct me if I'm wrong. Looking at the combustion chambers it looks slobbering pig rich to me.
 
Zero W9 experience here.......but....... don’t they require different pistons than the W2’s?
 
justinp61 said:
I don't run alcohol so someone correct me if I'm wrong. Looking at the combustion chambers it looks slobbering pig rich to me.
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I looked at that. If that’s the way the chambers looked coming off the engine, without being cleaned or wiped off, then it’s probably not rich.

That clean area has no fuel there, so that means all the fuel in the chamber is stacking on the exhaust side.

If that’s the case, you’d need to figure why there is no fuel there and remedy the issue(s).
 
yellow rose said:
I looked at that. If that’s the way the chambers looked coming off the engine, without being cleaned or wiped off, then it’s probably not rich.

That clean area has no fuel there, so that means all the fuel in the chamber is stacking on the exhaust side.

If that’s the case, you’d need to figure why there is no fuel there and remedy the issue(s).
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I have seen chambers that looked like that on a BB chevy that a buddy of mine was freshening up. Our thoughts were that it was rich and the intake charge was washing that side of the chamber.

I have been wrong many times before.......... just ask my wife.
 
justinp61 said:
I have seen chambers that looked like that on a BB chevy that a buddy of mine was freshening up. Our thoughts were that it was rich and the intake charge was washing that side of the chamber.

I have been wrong many times before.......... just ask my wife.
Click to expand...


Where they are clean there is no fuel. It’s the opposite of what most think.

You can kinda see the next chamber down in that picture and it kinda looks the same. If that’s the way they came off the short block, you could lose a bunch of CFM and gain a bunch of power just fixing the fuel separation issues.

Of course, that is easier said that done, especially if you are following someone else’s work.
 
RAMM said:
Ive heard about 400cfm W9,s but never had them in my hands or on my dyno. Would like to see some for sure. J.Rob
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If I get my W9 heads ported should I get a port job that goes 400cfm even if I'm only building a 625hp engine?
 
I have to think a 400CFM head probably has some poor lower-lift performance, or some other sacrifices, to get to 400CFM. I could be wrong, but...
 
@RAMM any chance you know what the top of the piston looks like? Or have a pic?
 
gregcon said:
I have to think a 400CFM head probably has some poor lower-lift performance, or some other sacrifices, to get to 400CFM. I could be wrong, but...
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I'm just thinking that if there is little cost difference between say a CNC job that go 350cfm and 400cfm is there any real downside of not porting the head to it's full potential.
 
67autocross said:
I'm just thinking that if there is little cost difference between say a CNC job that go 350cfm and 400cfm is there any real downside of not porting the head to it's full potential.
Click to expand...

Most places charge more for more cfm. Plus, your cfm should be matched to your cam and application etc. Then....the more metal that's removed, the more risk of oil-water mixing.
 
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