Comp XE268H v Crow 18619 - 318

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Thanks all. From the comments I have come up with below.
I like the idea of a roller cam but haven't had one retro fit before.

Howards retro fit hydraulic roller.
Hydraulic Roller Big Mama Rattler Camshaft; 1964 - 2003 Chrysler 273, 340, 360 2000 to 5700 Howards Cams 718045-09 | Howards Cams

Isky mega 270 with 1.6 rockers
Mega-Cams™ [390171] - $208.00 : ISKY Racing Cams, Do It Right

Howards HRC711451-08
Howards, Hydraulic Flat Tappet Camshaft, Chrysler SB 273-360, 220/220 @ .050, .506/.506, 108 LS-Competition Products
 
I would call around to each place to see if they have that cam in stock. Dealer 1st, then the grinder. I ordered a Howard’s cam a good while back and they had no cords to grind. It’s worth calling them to see if they have any.
If they do, let’s us know.
 
rumblefish360 said:
I would call around to each place to see if they have that cam in stock. Dealer 1st, then the grinder. I ordered a Howard’s cam a good while back and they had no cords to grind. It’s worth calling them to see if they have any.
If they do, let’s us know.
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Thanks. I am not in a hurry as car build will take a while. Happy to wait for the correct item.
 
Def call anywhere to make sure the cam is in stock.
I like the isky mega 270 also. Or the lunati i linked earlier that should be in stock. if you want to run 1.6 rockers you need some gentle lobes with hydro lifters.
 
On the subject of lobe rates, the Howards profile I had referenced calls for 122 seat and 335 open pressure @.506 lift with new springs (figure on 7 pounds less after break in). So there’s no doubt it is fast rate/high pressure profile. For comparison, the rates for it would work with my “shelf baby” Racer Brown solid thats [email protected] (lash lift) /[email protected] (125 seat/335 open after break in). As far as the high or low rate lifter rate debate, both have their merits. Incidentally, Isky is one of the first manufacturers that developed high lifter rate cams. I do recommend contacting Mike at B3 racing engines whenever setting up a performance valve train, because valvetrain stability problems are caused by incorrect geometry as much as any other factor. Here’s some of his handiwork for sale posted by another member.
[FOR SALE] - PRW rockers 273-360, 1.6 Ratio, with B3 racing relocation kit
 
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Hysteric,
[1] Vizard was an engineer first [ Aero Space ], magazine writer second. At least give the man credit where credit is due. I wouldn't call his 520+ page A engines book a 'magazine'....
[2] If Jones' cams are winning races for their owners, the word soon gets around & everybody would be using them. But not everybody is using them....
[3] Comp Cams opened it's doors in the mid/late 1970s, using Harold Brookshire's cams. That business grew because Harold's cams were winners....
 
I’ve read somewhere after working at Ultradyne and Lunati, Brookshire worked a short stint at Howards cams. Looking at the area “under the curve” listed in the catalog on the grinds stated “designed to take advantage of the .904 lifter”, and the fact that there is also a page of “Brookshire Lobes” on the lobe list, I can believe it.
 
Garrett is 10000% correct when he says Isky was one of the first to develop high rate of lift cams. I used the B-777 cam in a few 440 engines, & I picked it out of an Isky 1974 catalog. It could have been in earlier catalogs...
I was so impressed with it that I had a copy made by a local cam grinder, who also used the profile in other engines with great success.
The B-777 was a SFT cam. 240 @ 050, 268 @ 0.020". That is only a 28* difference....back in the 1970s. See how many 'modern' SFT cams of similar 050 duration you can find with 28* separation. Harvey Crane called this the 'Major intensity' & said: '..the smaller the intensity #, the performance will increase!.
 
Bewy said:
Hysteric,
[1] Vizard was an engineer first [ Aero Space ], magazine writer second. At least give the man credit where credit is due. I wouldn't call his 520+ page A engines book a 'magazine'.....
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Sorry but changing parts and playing with a dyno doesn't qualify as scientific research in my view. I have a book by him on carbs and intake I now wouldn't bother referring to.

If I wanted a deeper understanding of how this stuff actually works I wouldn't go to vizard for any of that.

If you think Vizard is the pinnicale of engine building you need to get out more.
 
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So are you absolutely married to a hydraulic? If you're going to go to an aftermarket rocker, why not a solid? In a tight quench, honest 10:1 318 something like this might be worth considering LA Small Block Solid Lifter Camshaft Otherwise the Isky 270 Mega or whoever is currently grinding the old Crane HMV 272 would work well.

I lean away from 1.6 rockers and super beading edge lift rates on the street. Sure they make more power on the top end. But many require some pretty crazy spring pressures. That's just more loading on the valvetrain (more wear) and a lot more parasitic loss. Run absolutely no more valve spring than you have to, less is more.
 
I wouldn’t recommend going for the high rate of lift with the high ratio rockers with hydraulic anything at the present, either. Not just because of wear, but because the reputation hydraulic lifters have now. The last time I talked to Ken at Oregon Cam Grinders, he had some roller cam cores, if you want something a little more custom.
 
I would use the Comp cam definitely but use solid flat lifters. I use Trend H-13 solid lifters and love them, a little costly though but will worth the money to me. They have many advantages, mainly 68+- gram weight. p-rods run in the lower lower half of the lifter and they have a hellava radius on the face you can easiy see with the naked eye. You will need longer P- Rods. I use Trend PRods also. The comp 268S is an excellent choice and will pull like a raped ape to almost 6200. I only run a xs274S in my 512 lowdeck. Don't use more spring that needed, just watch your tach. Good luck to you. Oh yeah, run the longest p-rods you can fit. I find thes extreme energy cams tune very easy.
 
Hysteric,
Never claimed that Vizard was the pinnacle of engine building. Haven't heard him claim that either. What he does claim, he backs up with testing. How many do that?
His 'writings' are aimed at hot rodders & no doubt some of it also applies to professional engine builders.
 
Garrett Ellison said:
I wouldn’t recommend going for the high rate of lift with the high ratio rockers with hydraulic anything at the present, either. Not just because of wear, but because the reputation hydraulic lifters have now. The last time I talked to Ken at Oregon Cam Grinders, he had some roller cam cores, if you want something a little more custom.
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How about something like this. Too much cam?

Hydraulic Roller Big Mama Rattler Camshaft; 1964 - 2003 Chrysler 273, 340, 360 2000 to 5700 Howards Cams 718045-09 | Howards Cams
 
Because you’re talking about a stock stroke 318, I would go with this one if it were available.
Hydraulic Roller Rattler Camshaft; 1964 - 2003 Chrysler 273, 340, 360 1800 to 5500 Howards Cams 718005-09 | Howards Cams
But if you can’t find one, Oregon hydraulic roller grind 1386. 224/[email protected], 280 advertised, .525 with 1.5 rockers. It comes on a 110 LSA, but get it ground on a 108. FWIW, in your combination and goal set, I would go with the Oregon cam on a 108 with a set of 3.23 gears and a 25-27 inch tire, and I wouldn't look back. Most 2500 rpm shelf converters are going to be on the tight side. There are a lot less complaints about selecting a cam that may be too small for the combination as opposed to one that is too large.
 
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I’m glad to see you folks are giving this exotic build the careful consideration it deserves with regards to cam selection.
:usflag:
 
OldmanRick said:
This thing would be nasty in a 318, With good heads.

PLYMOUTH Howards Cams 718045-09 Howards Cams Rattler Camshafts | Summit Racing
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Ok, y'all sucked me back in.:)

Yes, i was aggressive with this pick, and maybe i read the op's wishes wrong. But, for a around town "sunday" ride, fairgrounds, drive in's, shows, etc, that cam would give him great sound and still perform well being able to use a full on timing curve with the alum. heads.

I based the pick off a buds 10.2 to 1 289 early mustang with a very similar cam and fully ported 351W heads with a 2800 stall & 3.90 gears. Sounded like a stout bracket car and still cruised well on the street. Best part was it was soft enough to not blow the tire off on the street, but would pull your teeth out from 3k to 6k.

I figure if a 2.87 stroke can run that way, the 3.31 should eat some of that up.
 
That cam would probably work pretty well, but like you said, to fit the intended goal, the Baby Rattler (they call it the hydraulic retrofit rattler, but the other two Rattler cams are Big Mama & Big Daddy Rattler, so it kinda fits!) would have good manners. As would the Oregon cam grind. Which cam will be dependent on gear selection, which will be dependent upon the amount and distance of highway driving. I figured Australian road trips would be more comfortable with a slightly milder cam and a 3.23 gear. The old standard .480 lift 280 duration or thereabouts cam that every one ground in the eighties would work here. And the happy combination cam for this might be one of the old Mopar purple shaft .474/.480 [email protected] cams.
 
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