Camshaft recommendation for PMO'd 2.4S ? Options

[ArtechnikA]

I know they exist
I wish I knew you were looking
my buddy just sold a set about 3 weeks back.. fairly reasonably too...

3 weeks ago we were on the roadtrip to MN and back and wouldn't have been able to afford them, reasonable or not. Still getting caught up from that expense, just in time to go buy this winter's heating oil contract, right ahead of the property tax. Things get 'normal' again around October...

If you come across another set, keep me in mind.

It finally ocurred to me to go check the carbs I've got - they've been boxed since i finalized that deal more than a year ago. Took the rainsields off and - well, they look a lot like that picture! They extend about an inch up over the baseplate, maybe 2 inches down into the velocity stack. I thought I remembered the 40's extending nearly to the top of the stack. Don't s'pose you have any meansurements so I can see what it is I've really got? ( I've seen the standard 40 aux vent's and these are definitely taller than those, but they don't come near the top of the stack... ). These carbs had previously been used in a track car and have all the earmarks of having been set up right.

( Sorry about the temporary thread hijack - as you were... )

[amallagh]

So if I glean some of the different opinions expressed here then the Solex cam is better optimised for a carbed engine then the S profile.

The reduced overlap seemed to be one of the factors that drove this so I surprised to see someone suggesting GE cams profiles which I thought had a lot of overlap. But maybe they were talking just for pure racing and weren't worried about the low to mid range.

On a comparative basis then I would still be interested if anyone had any experience of the relative peak power outputs of E, Solex and S cams on a Weber/PMO 2.4 with S heads. I understand that the absolute power depends on other factors. (In have PMOs with 40/34 venturi, std S heads & ports with 1.5" Bursch headers and a fairly std Bursch 911 exhaust to keep the noise down for use on track)

I see people saying that it is 'impossible' to optimise things for track and road, and of course this is correct. But I am looking for that compromise set up for a road car that is also used for some competition use.

My decision appear to be whether to go for another set of S cams or change to the Solex or E cams if I'm trying to improve the mid range a little without compromising the top end too much. That's why I'm interested in some estimate of the relative peak power outputs of the 3 choices.


If the Solex cam is ideal for a PMO set up with S heads then the next question if where to I get a new or reground pair at a reasonable price ?

[ArtechnikA]

If the Solex cam is ideal for a PMO set up with S heads then the next question if where to I get a new or reground pair at a reasonable price ?

Web-CamDo the Product Search, select Automobile, Porsche, 911 SOHC 12valve, and you get a nice page of options. At the top is the 1966 Solex profile, which per the July 2008 price update are US$718 in hard-weld, $878 on new billet. All the popular profiles are the same price, as you'd expect.

To do it right, you'll also need 12 matched rockers - WebCam will hard-weld and grind your cores for $65 each. They list rebushing separately.

The Euro is at historic rates vs the US$. Strike while the iron is hot.

( I have no personal affilliation with WebCam, and they don't need me to shill for them. )

[J P Stein]

Like most of these old parts (or old style), finding them takes some doing.
The best place is Pelican's 911 classifieds, IMO. The classifieds of Panorama also has a some old style stuff. My Solex cams came from there....one NOS-sill-in-the-box & the other fresh from a touch-up by Web Cams.....center-oilers. My latest find on Pelican was a NOS set of Mahle 10.5 :1, 90 mm P/Cs. They were posted about 15 minutes before I bought em'. (IMG:style_emoticons/default/biggrin.gif) Stuff like this does not come along often but the timing was perfect.....blew my rebuild budget to hell tho.


I forget exactly where I got these....no matter, these are not often seen F/S. I think they are a good torque booster.....old pic. of long aux venturi peeking out the stacks.

[J P Stein]

The "ideal" cams for carbs would be the T cams......smooth, torquey, no drama & falls on it's face about 6K. I have no idea who has tested (real life conditions) all or even many of the available grinds. The Solex jobbies were recommended to me by Steve Weiner....I listened and am not sorry.

Post on the Pelican 911 engine rebuild forum. There are several pros there that will give conflicting advice on the best "combo" cams. OALA....everybody has one.
I learned 40 years back what overcamming & overcarbing can do to you in a supposedly "combo" motor.....a real pain in the ass when 90% of the time is spent on the street.

[ArtechnikA]

I forget exactly where I got these....no matter, these are not often seen F/S. I think they are a good torque booster.....old pic. of long aux venturi peeking out the stacks.

That's what I remember mine looking like, so here's the $46 question - is that picture of 40's or 46's? (I can't -quite- read the data tag on the body...)

[J P Stein]

40s...sorry about the lousy pic. (IMG:style_emoticons/default/biggrin.gif)

[ArtechnikA]

40s...sorry about the lousy pic.

Actually it's a great pic, it's just a lousy data plate. I have a hard time reading the little numbers on the real carb when it's in my hand.

With scant evidence to go by, I think I'm about to conclude that the aux vent height on both the 40's and 46's is (about) the same but the 46 stacks are taller and the aux vent's don't come up as high into them.

One of these fine days I'm gonna hafta actually inventory what I got in that buy so I'll know what parts to be on the lookout for. I'd probably spend stupid money for something it turns out I already had (and I hate when that happens...).

I'd love to see a picture with a 40 and a 46 aux vent side by side - with a millimeter ruler...

[TimT]

Amallagh,

I have a set of WebCam 158R grind cams, three journal cams, low hours. These cams are sort of a "Solex+" cam.

$300 US + shipping, given the way the euro and pound are against the dollar, this is a pretty good deal (IMG:style_emoticons/default/dry.gif)

[TimT]

I forgot to add, I have dyno plots somwhere of these cams in a 2.2L engine. Initially the car was 50/50 street track, when I finally started using it 100% track I got a set of dougherty DC-60 cams. The set up on my car was Weber 40s with 32mm venturis, and tall secondary venturis.

[J P Stein]

Hay, Tim, that is a good buy.

[6freak]

Hay, Tim, that is a good buy.

Sent the man a PM ...will they work on my AX/ street car he says yes and so does my other informent who is a great motor builder! what do you think JP.....building a 2.0 to a 2.2 ..just looking for somemore opinions and i need lots of help

[amallagh]

Amallagh,

I have a set of WebCam 158R grind cams, three journal cams, low hours. These cams are sort of a "Solex+" cam.

$300 US + shipping, given the way the euro and pound are against the dollar, this is a pretty good deal (IMG:style_emoticons/default/dry.gif)

Tim,
I'm interested in your cams. I looked at the Webcam site and couldn't find a reference to the 158R grind. Do you have the full cam spec, duration, lift, etc. details or can you point me to where they are ? Also interested in seeing the dyno plot you mentioned. I'll PM you my email
Thanks

[6freak]

Amallagh,

I have a set of WebCam 158R grind cams, three journal cams, low hours. These cams are sort of a "Solex+" cam.

$300 US + shipping, given the way the euro and pound are against the dollar, this is a pretty good deal (IMG:style_emoticons/default/dry.gif)

Tim,
I'm interested in your cams. I looked at the Webcam site and couldn't find a reference to the 158R grind. Do you have the full cam spec, duration, lift, etc. details or can you point me to where they are ? Also interested in seeing the dyno plot you mentioned. I'll PM you my email
Thanks

is this gonna be one of those he told me i could have it first and you ended up with it things lets hope not ..anyway there some REAL CARB porn in this thread

[sixnotfour]

the cam card is listed on the website, looked at it 3 days ago for 6freak.

[Root_Werks]

[quote name='Phoenix-MN' date='Jul 16 2008, 07:19 PM' post='1057105']
(IMG:style_emoticons/default/agree.gif) (IMG:style_emoticons/default/cool.gif)--><div class='quotetop'>QUOTE(scotty b @ Jul 16 2008, 06:14 PM) </div><div class='quotemain'><!--quotec-->
+1 for Solex (IMG:style_emoticons/default/driving.gif) S is great once you hit 6000. Under that and they're pretty blah
[/quote]

I have the "Solex" grind in my 2.5L, Lots and Lots of smiles. Pulls strong all the way to redline

Paul
[/quote]

I have the same Engine, 2.5 Solex cams, 9.5:1, nice linear power. Great for street cars and ocasional stompings.

(IMG:style_emoticons/default/driving.gif)

[amallagh]

the cam card is listed on the website, looked at it 3 days ago for 6freak.

Found it. Must have been blind first time round. I see the 158 grind is very simiar to an E cam with a bit more lift. I was really trying to get something a bit hotter like the Solex.
I see DR Camshafts does a DC30 profile which is a Solex grind with 102 degree lobe centres rather than 97 degrees. Presumably this just improves the low down running especially on carbs by reducing the overlap slightly ?

Sounds like a good option. Anyone got any experience of this one.

[J P Stein]

Solex & S cams have the same 97 deg lobe centers.The big difference here shows while timing them. The S has a lift of over 5 mm while the Solex is about 4mm at TDC overlap(IIRC). It's tough for the average Joe to compare 2 cams with different lobe centers but in this particular case it's easy to see that the S cam is gonna be more peaky and less happy at low revs. When it starts to scavenge, tho........yeehaw.

Tim knows his stuff and his price for those cams is as good as I got 8-9 years ago for the Solex jobbies...just make sure you have the timing specs. (IMG:style_emoticons/default/biggrin.gif)