Opinions on cam recommendation

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Ted265

Ted265

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Hi guys,
First post here but I have been reading these forums for quite a while - Lots of good info on this site.
Anyway I am looking for second opinions on a cam that was recommended for my 318 by a local grinder.
I was originally looking at a howards 711651-10 for this engine (265/273adv, 218/[email protected]", .502/525 lift) but they reckon 3-4 months wait time on the cam, then another 3-4 weeks for international shipping.

Car is a 1969 valiant VF coupe (Australian dodge dart), 3100lbs, 3.23 gears, 245/60R15 tires, power brakes, 904 torqueflight with shift kit, have a std convertor at the moment but will probably swap this to a higher stall unit to match the cam.
Engine is a 1973 casting 318 +0.060 bore (327CI).
KB 167 pistons (0.013" above deck) 9.8:1 CR with 0.051" head gasket, resized std rods with arp bolts, floating pistons, crank reground and rotating assembly balanced.
Have a edelbrock 650CFM AVS2 carb and mildly ported Weiand action plus dual plane manifold, 1 5/8" tri-y headers twin 2.5" exhaust.
Aeroflow alloy heads - 2.02" inlet & 1.6" exhaust valves with casting flash in the ports cleaned up, some bowl blending and a decent valve job. These flow similar to edelbrock & speedmaster heads OOTB but they haven't been flowed after the cleanup on them. 1.6 ratio rockers.

The cam recommended from my local grinder is a solid flat tappet but to me seems a little bit big for my intended use (street car/cruiser with a bit of punch) what do you guys think?
Hopefully cam specs are attached, will be installed on 106° intake centreline.
Is it safe to compare a solid cam duration advertised at 0.020" with a hydraulic advertised at 0.006"? Or is there more to it when comparing solid to hydraulic profiles?
Cheers,
Ted

20211116_191830.jpg
 
Welcome aboard Ted!

The given rule of thumb IIRC in comparing Hyd. vs solid cams is the solid should be approximately 6*’s larger to make it equal or as close as possible.

Id run that cam in a heart beat flat. It’ll do what you want.
 
I haven't seen that grind yet but there's not a whole lot of street specific builds that wouldn't work very well in. It's a real winner with your combination.
 
My math gets an Ica of just about 55*. When I punch that into the Wallace Calculator, it spits out a CCP (Cranking Cylinder Pressure), of 172psi and a Dcr of 8.33, which is not too high for Alloy heads. You probably could have gone for a bit more CCP but I don't know about your gas, and it sortof depends on your elevation.
With pistons .013 ABOVE deck your Quench maths to .038 which is about perfect.
I think it will run gangbusters in that lightweight body.

IMO, a 106 LSA might be a lil tight for a 904; but I don't think you will notice, as, at WOT, those pizza-cutter 245s are gonna be on fire anyway. I think I would install it at no more than 2* advanced in your combo.
Like you, I would at least try the stock convertor.
Slam it in and go have some fun.
 
Is that a Crow cams cam? Unless they have improved, their accuracy leaves much to be desired......
The specs are good & suitable for your application. To compare hyd to sol, you subtract 8-15* from the sol @ 050 number to approximate a hyd grind. 8* with tight lash such as 0.012" & 15* for wide lash like 0.030". Example, 0.024" lash sol cam you would subtract 10*, so 230* sol = 220* hyd [ @ 050 ].
Smart choice on the Edel carb.

I would use an Isky cam.
Hyd: 270 Mega
Sol: 274 Mega

Lifters. Buy 'new' ones at your peril. Use your existing factory lifters & send them to Clive Cams in Melb for refacing. If you want to go with solids, you can convert the hyd lifters to solids by removing everything below the inner piston & then using s/steel washers under the piston to get it positioned at the correct height.
 
Thanks for the input guys, sounds like this grind might be the go then. I was a bit iffy on the sub 0.020" duration numbers and thought it might bleed off too much cylinder pressure, while I have a reasonable understanding of the basics, the finer details of lobe profiles i don't have a good handle on yet.

AJ - They were going to grind this on a 110 LSA and I was go in to install it 4° advanced for a 106 intake centreline.
How do you calculate the intake closing point?
I've seen DCR calculators online that use the advertised valve events (assuming that's .006 for hydraulic and .020 for solid?) and others that use the @.050 timing + 15° - this cam would have a Ica of 65° or 60° if installed straight up depending which method you use.
Elevation where I am is about 200ft above sea level, and it will run on 98 octane unleaded - from what I can tell this is about 91/92 octane the way you guys rate your fuel. Heads are not assembled yet so I could still mill them a little to bring the compression up a bit higher but I think that money might be better put towards a geometry correction kit - what I've got with these heads and the 1.6 rockers is not terrible but not great either.
Will probably try it with the std convertor initially and throw it on a chassis dyno and take the printout and specs to the covertor shop like I did with my other valiant - that worked out very well even though it was a pain swapping them out.

Bewy - this grind is from Tighe cams, they ground the cam in my 265 and I am pretty happy with it, so I thought I would see what they had for the 318.
Unfortunately I don't have an old set of lifters to be refaced (sold them with the old cam) but I have found some new howards edm solids for a reasonable price. I thought most of the lifter problems people were having were with hydraulic lifters?
Will check out the isky cams but they might have the same core supply issues as howards.
Cheers,
 
Ted265 said:
Thanks for the input guys, sounds like this grind might be the go then. I was a bit iffy on the sub 0.020" duration numbers and thought it might bleed off too much cylinder pressure, while I have a reasonable understanding of the basics, the finer details of lobe profiles i don't have a good handle on yet.

AJ - They were going to grind this on a 110 LSA and I was go in to install it 4° advanced for a 106 intake centreline.
How do you calculate the intake closing point?
I've seen DCR calculators online that use the advertised valve events (assuming that's .006 for hydraulic and .020 for solid?) and others that use the @.050 timing + 15° - this cam would have a Ica of 65° or 60° if installed straight up depending which method you use.
Elevation where I am is about 200ft above sea level, and it will run on 98 octane unleaded - from what I can tell this is about 91/92 octane the way you guys rate your fuel. Heads are not assembled yet so I could still mill them a little to bring the compression up a bit higher but I think that money might be better put towards a geometry correction kit - what I've got with these heads and the 1.6 rockers is not terrible but not great either.
Will probably try it with the std convertor initially and throw it on a chassis dyno and take the printout and specs to the covertor shop like I did with my other valiant - that worked out very well even though it was a pain swapping them out.

Bewy - this grind is from Tighe cams, they ground the cam in my 265 and I am pretty happy with it, so I thought I would see what they had for the 318.
Unfortunately I don't have an old set of lifters to be refaced (sold them with the old cam) but I have found some new howards edm solids for a reasonable price. I thought most of the lifter problems people were having were with hydraulic lifters?
Will check out the isky cams but they might have the same core supply issues as howards.
Cheers,
Click to expand...

First, let's clear something up. There is no "bleeding off cylinder pressure". Taint how it works. When speaking of intake valve closing (IVC), there is no pressure built "yet". When the intake valve is open, the piston is on the way down, drawing in air and fuel. "somewhere" after bottom dead center (BDC) the intake valve closes and the cylinder begins to build pressure. The later the IVC, the less pressure is built. So it's not a case of bleeding off, it's a case of simply not building "as much". I too like that Howards grind, as I do most of them. They have a lot of lift per given duration and that takes greater advantage of Mopar's larger than average .903" lifter diameter, even though those grinds "may not be" .903" specific, they are still good grinds.

Why not give Ken Heard at Oregon Cam Grinding a call? He might have a grind that's close and will perform just as good. He's ground several for me. I have one of his grinds on the dining room table right now I am getting ready to install in my current slant 6 build. Talk to Ken and give him those specs. I bet he has something compatible.
 
Bewy said:
Is that a Crow cams cam? Unless they have improved, their accuracy leaves much to be desired......
The specs are good & suitable for your application. To compare hyd to sol, you subtract 8-15* from the sol @ 050 number to approximate a hyd grind. 8* with tight lash such as 0.012" & 15* for wide lash like 0.030". Example, 0.024" lash sol cam you would subtract 10*, so 230* sol = 220* hyd [ @ 050 ].
Smart choice on the Edel carb.

I would use an Isky cam.
Hyd: 270 Mega
Sol: 274 Mega

Lifters. Buy 'new' ones at your peril. Use your existing factory lifters & send them to Clive Cams in Melb for refacing. If you want to go with solids, you can convert the hyd lifters to solids by removing everything below the inner piston & then using s/steel washers under the piston to get it positioned at the correct height.
Click to expand...
Does Clive also regrind? Maybe he could do something "in country" so to speak and get faster results. You should really give these regrinding companies a chance. Some of these guys are really sharp. Might can save a dollar or two as well.
 
Yeah here's Clives' web site.
Clive Cams > Home
Looks like he knows what's up. I'd give him a shout. I bet he can fix you right up.
 
@Ted265 AJ & Bewy are making a lot of sense. I do however suggest that getting to caught up in exacting specs may drive you crazy and the difference in actual feel and dyno results will be minimal. Do the best you can and do worry. The closer you get to the optimal set up the better it will be. You’ll never miss a slight off the mark. Do so try though.

Ive run a couple of cams at & around that 218@050 mark and there really very drivable with very good low end torque & a nice top end.
 
Yeah both Clive and Tighe cams do re-grinds, Tighe cams is about 15 minutes up the road from my work. I've heard good things about Clive cams but I haven't run any of their grinds.
I contacted Clive today and his recommendation was pretty similar - solid 283°adv, [email protected]", .317" lobe lift, 110°LSA & 0.020" lash. He called me back while I was in the middle of something at work so I didn't get the chance to ask him what lift his advertised duration was measured at or the duration at .200". I will call him back tomorrow when I've got a few minutes to talk about it some more.
Tighe cams also had a smaller solid grind [email protected] & .340 lobe lift but he thought it would be too small for this engine.
 
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