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Marv D · 09-09-2017, 10:06 AM

http://www.airflowresearch.com/180cc...cylinder-head/

Depending on your deck height / piston configuration and resulting compression,,, I'd HIGHLY suggest you stick with the 0911 (65cc) or 0916 as (75cc) for the straight plug version. The angle plug does offer some advantage, BUT at this level it's a onsey - twosey thing and your sanity in header choice and plug wire clearance is HUGE compared to the small advantage of the angle plug.

For cam,, Cant really make any suggestion without knowing exactly what you have for compression (deck clearance, piston, bore, stroke, gasket), intake, carb / injection, and the complete drive train from converter to tire diameter, vehicle weight, exhaust configuration,, and a ton of things beyond the scope here.
Like SNJ is saying,, the expertise of guys like Chris Straub is well worth the $ spent. They are not just offering you free phone advice and selling you a shelf stock cam that seems to fit what info you can offer,,,,, they are working through the engine pulses at the average RPM your working YOUR combination of parts,, and picking a lobe that fits the need.

In all honesty most of the guys that 'design' a cam are doing their magic, then picking lobe profiles from the master lists of their favorite grinder, and ordering the core with lobe "A" for intake lobe "B" exhaust on a xxx° LSA and having the desired distributor gear pressed on.

If you look youcan usually find your custom cam lobe in the master list of one of these companys like Bullet. Here's their hydraulic roller lobe profile master.
http://www.bulletcams.com/Masters/HRlobes.htm

And that is a reasonable option too. The guys at Bullet are EXTREMELY sharp and will work with you to pick a combination of lobe profiles to compliment you ruse,,, or come up with a shelf stock cam that is pretty close.

You can get hydraulic roller lobes as mild at 180 and 190 which is the same as the STOCk GM TBI cams. The trade off in short duration is you sacrifice LIFT,,, and the AFR heads LOVE lift. Even with a roller you can only get so much lift , given a particular duration, os a SBC core befor eyou have to run such spring pressures it puts durability (and the hydraulics) at risk.

Just what little we know,, I'd really suspect something with a 195-200° @ 0.050" and a .30 - .35 lobe, with a set of 1.6 rockers to get lift up to .55 if possible is going to be where most will suggest if you set compression at no more than 9.2:1, and use the AFR head on carburated a 355 intended for WORK and towing and unlikely more than 4500RPM

BUT, that's just a guess. I'm not a cam designer and there are way too many unknowns to go deeper.

09-09-2017, 10:06 AM	#12
Marv D Registered Truck Offender Join Date: May 2008 Location: hells training ground (aka Ariz) Posts: 3,118	Re: SBC Alu Heads Designed for Torque http://www.airflowresearch.com/180cc...cylinder-head/ Depending on your deck height / piston configuration and resulting compression,,, I'd HIGHLY suggest you stick with the 0911 (65cc) or 0916 as (75cc) for the straight plug version. The angle plug does offer some advantage, BUT at this level it's a onsey - twosey thing and your sanity in header choice and plug wire clearance is HUGE compared to the small advantage of the angle plug. For cam,, Cant really make any suggestion without knowing exactly what you have for compression (deck clearance, piston, bore, stroke, gasket), intake, carb / injection, and the complete drive train from converter to tire diameter, vehicle weight, exhaust configuration,, and a ton of things beyond the scope here. Like SNJ is saying,, the expertise of guys like Chris Straub is well worth the $ spent. They are not just offering you free phone advice and selling you a shelf stock cam that seems to fit what info you can offer,,,,, they are working through the engine pulses at the average RPM your working YOUR combination of parts,, and picking a lobe that fits the need. In all honesty most of the guys that 'design' a cam are doing their magic, then picking lobe profiles from the master lists of their favorite grinder, and ordering the core with lobe "A" for intake lobe "B" exhaust on a xxx° LSA and having the desired distributor gear pressed on. If you look youcan usually find your custom cam lobe in the master list of one of these companys like Bullet. Here's their hydraulic roller lobe profile master. http://www.bulletcams.com/Masters/HRlobes.htm And that is a reasonable option too. The guys at Bullet are EXTREMELY sharp and will work with you to pick a combination of lobe profiles to compliment you ruse,,, or come up with a shelf stock cam that is pretty close. You can get hydraulic roller lobes as mild at 180 and 190 which is the same as the STOCk GM TBI cams. The trade off in short duration is you sacrifice LIFT,,, and the AFR heads LOVE lift. Even with a roller you can only get so much lift , given a particular duration, os a SBC core befor eyou have to run such spring pressures it puts durability (and the hydraulics) at risk. Just what little we know,, I'd really suspect something with a 195-200° @ 0.050" and a .30 - .35 lobe, with a set of 1.6 rockers to get lift up to .55 if possible is going to be where most will suggest if you set compression at no more than 9.2:1, and use the AFR head on carburated a 355 intended for WORK and towing and unlikely more than 4500RPM BUT, that's just a guess. I'm not a cam designer and there are way too many unknowns to go deeper. __________________ Still playin with trucks, even at my age! When you're dead, it's only a problem for the people around you, because you don't know you're dead. .....It's kinda the same when your STUPID. I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.