So I'm thinking about swapping in my rebuilt 292 Y block into the '30 sedan. This motor has been together for about two years now just waiting to be put to work, but before I do this, I would like to ask what the camshaft experts think about the cam that is in this motor. Motor has stock style pistons 0.40" oversize, Offenhauser 3 two intake with three 94's with progressive linkage. Transmission 3 speed manual with overdrive, rear axle is a '48 Ford banjo 3.73 ratio and 750X16 rear tires. In a 1930 Model A tudor. The camshaft in the rebuilt motor is a new Comp Cam unit with: .471" Gross lift both intake & exhaust at .050" lift intake opens at 4* BTDC closes at 40* ABDC at .050" lift exhaust opens at 43* BBDC closes at 7* ATDC Duration @ .050" intake, 224* exhaust 230* lobe lift , .3140 both intake & exhaust lobe separation 108* So knowing how hard it is to swap cams in a Y block should I stick this motor in with this cam OR swap it out with something better?
I have no input but following along to hear the comments since I hope to be building a y-block for myself soon...
I'd look at the most aggressive cam that the factory put in the Y block and Compare the specs on that cam to your cam. If anything, add more lift; add lift only if you're sure of the piston to valve clearance. BTW I don't think the cam you have is necessarily a bad choice.
Ditch the Offenhauser 3X2. Tests show this is one of the worst preforming intakes made for the y-block.
Here's the cam I used in my T-Bird 312. It idled smooth and had good power through the whole driving range. I did have the G heads and the T-Bird rockers. I was running the stock intake with a Holley 600 cfm carb. I had a Ford-O-Matic and a 3.10 rear.. I think the tires were 205/75 R14.
Good decision. John Mummert makes the top preforming aluminum 4bbl intake on the market for the y-block.
Yep, I ran an Edelbrock 3x2 for a bit with three Holley 94’s. After fighting it for a while, I sold that setup and put a 57 intake on my 56 as well. If I buy an aftermarket intake, it will be a Mummert. But, I also have a closed hood car so looks isn’t as important for my application.
Absolutely, find an Edelbrock 357 and 20 more free horse power. I’m sure you don’t want to to do it but advancing your current cam 4 to 6 degrees or adding 1 more point to your current compression which was approximately 8-1 or 8.4-1 factory will do more than any cam.
46, I’m taking the liberty of forwarding the link to yblocksforever to this question. For other y block guys to see. Particularly the comment by Joe-JDC. I’ve heard of this problem before, most likely in a post by Ted Eaton, but I’m not sure. Being ground on the wrong angle makes it almost impossible to degree the cam in properly. Might not be the case with your cam, but I’d have the degree wheel out and be looking for it for sure. http://forums.y-blocksforever.com/Topic165467.aspx If you go to Ted’s site, you’ll find comments on the intake manifold, and the dyno testing. Scroll,down and you’ll find the 3x2 manifolds and the link to the Offy that Joe Craine ported. It explains his comment in the post above. https://www.eatonbalancing.com/ I’ve run 3 cams from John Mummert’s site. To me his recommendations are a bit conservative, but .I’ve never tried to run one against an auto. All mine were manual transmissions. But maybe I’m just more used to slightly more radical cams than someone else. You can scroll down to the camshaft listings and compare it to your’s to get an idea of how they compare. http://www.ford-y-block.com/valvetrain.htm None of this addresses how you handled the oiling/center cam bearing/camshaft bearing groove/soft cam bearings on your build. But if it’s not familiar to you that’s something else to research.
I bought this set up for super cheap knowing the intake was a poor performer. I have been on the look out for a better one.
Well, I can easily advance the cam, that would be easier than replacing it. I think my compression is more like 9:1 now with the G heads. I think anyway.
I read this or something like this before I installed this cam because for some reason I checked valve position at each cylinder. Thanks
You got that right, the worn out motor that is in the car has the same cam and has low vacuum at idle. But some of that (I was thinking) could be due to the loose pistons.
Please explain the degree numbers next to the valve open/close points. I don't understand the numbers in the brackets ( ) .
This is something Ted posted on the Yblocksforever site. And it brings up my concern, see how my cam opens the exhaust 10* latter that this one? also it opens the intake 4* latter than this one. The 4* may not be too much but 10* late on opening the exhaust? Anyway, I think I might just try to find this Isky grind because Ted likes it and you can't argue with that. Guess I should ask if anyone wants the new (but installed) Comp Cam for cheap!
The numbers in the brackets are the timing events at .050 valve lift, they give a more accurate depiction of the cam action. With the cam having lash of .012 the lifter isn’t doing anything until it gets on the ramp (the initial start of lift) and the ramps are gentle, the valve is not slammed open to full lift and it might have been Ed Iskenderian that first used the .050 value to show effective duration, until that first .050 of lift not much is really happening. The shorter event numbers aren’t as impressive to the “drive in crowd”, nobody quotes their cams duration at .050, they use the advertised duration numbers. But even then cams can be ground with quicker action so that lifter rise is more rapid. Two cams with the same duration values can be very different, that was one way “cheater” cams were more effective in stock cl*** racing at the drags, the lift and duration was correct when checked but the cam action allowed more air/fuel mix into the cylinder.
I see it now, they explain this inside the circle. Thanks! ok so now that Fordors got me straightened out, it looks like the Mummert cam (described in the yellow picture) opens the intake at 4* ATDC at 0.050". I guess that is what the -4* is trying to say.
My 32 has a 312 Y Block with a Comp Cams thumper cam. It has the G heads and an Edelbrock #373 3-2 intake with fresh Stromberg 97s set up and .040 over 10:1 CoyRoss pistons. I had to have a local machine shop deepen the grove to .o18" on the cam where oil leads to the rocker shafts. I recently completed a valve job and the machine shop installed stainless valves, hardened seats and new guides and machined the head for modern veetron oil seals. I had problems with oil getting into the cylinders fouling the plugs. I have a Tremec 5 sp to change the gears. And I added a PCV valve. As noted above, it was a bit troublesome setting up the three twos but this baby really pulls from the light. The guy beside me really has to get on his GT to get past me. I think it's a tribute to the ole Y block being able to keep up with the LS and Coyote motors. Would be nice if I had a set of Mummert heads.
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