Something to keep in mind is that the Crane cam is old.
It wouldn't be fair to have it compared to anything that's been designed in the last twenty years or so. Even if you could make a reasonable flat tappet to roller comparison.

Using your 205 @ .050" on a 108 LSA an example (with 4 degrees of advance ground in for a 104 ICL), and assuming a modest lobe profile such as that of a Magnum (in itself more than twenty old) so that the seat timing is about 270, it was shown that with a 9.3:1 compression ratio, you might be beyond what you could tolerate on regular fuel.
That's about all I'm saying there. You could run it but...
Same might be said of the Elgin cam. Old lazy intake lobe that while it has a modest .050" number, the long seat timing will kill torque.
​​​As for any kind of mastery, it's simple online calculators and some other software that I've been fiddling with to keep me from going crazy when I can't actually be building an engine. Thankfully, that has changed and am back to my own.

 

https://www.summitracing.com/parts/h...iABEgIvmvD_BwE
run this

 

I would pass, LSA is way too wide and the duration split is not productive on a 305.

 

I really like the magnum lobes, they really take off in the mid lift profile wise, are quieter than the hottest newest lobes and more durable as they do not require as much valve spring pressure.

As far as 87 compatibility goes, you are overlooking the fact the tiny stock cam runs on 87 just fine.

 

True for all of the above but remember the L03 was hardly a performance engine. I'll bet the timing was adjusted to compensate for low grade fuel.

 

its 4 degs lol and 110 isnt that wide

 

thats because dynamic compression isnt the end all be all determinant lol. But they have larger seat to seat durations in oem deals with ultra wide lsa

but low duration low lift wide lsa doesnt make a lot of power so not a lot of cylinder pressure to worry about

 

The stock cam is on a 109 LSA and 3° advanced.

 

true im thinking of the efi cams on 115-117. Also ran fine on 87 at more power than the L03

 

The Howard's cam is on a 112 FWIW.

As for DCR, agreed that it's not the be all and end all for a determination however when comparing apples to apples and then using some real world experience with apples, it's a pretty good gauge for the street.
YMMV.

 

Except it is 112 LSA. 4° changes alot on the exhaust side.

I just swapped from 1.7s to 1.5 rockers on the exhaust side of my 383. Added 20 ft/lbs down in the 1,500-2,500 rpm range with no loss anywhere else. The rocker change made the cam 5° smaller @ 0.050. This was on a 383 with an exhaust port only flowing 66% of the intake as well. I have 8 1.3 rockers on the way to further test. My 383 is getting a cam change based off the results but going to experiment a little bit more and see what it likes. I will first test the 1.3s on the exhaust and then the 1.5s on the intake.

 

Skinny,
Seems like it would be best if I just wait until October when Comp’s or Lunati’s newer present day designs might be available, rather than compromise with older lazy lobes.

 

Or...
This just in.
On Monday, July 18, 2022 at 10:37:20 AM EDT, Kevin Clemence <kdp.clemence@gmail.com> wrote:

Subject: New Jones Hydraulic Roller with Used OEM Lifters
Good Morning Mike

I've a quick question regarding the above subject.
I've a friend with a mild performance application (Gen 1 SBC 305) and he's keen on having you grind a cam for him. However he's balking at the notion that he's required to use your lifters as well.
Is this the case or can he reuse his low mileage OEM rollers?
Thanks in advance.
Kevin Clemence
Mike's reply:

It depends on the cam. If it's not a very aggressive design, he can run his OEM lifters.
If it's one of our more aggressive designs, the OEM lifters will collapse at higher RPM's, and cause issues.
Mike Jones
Jones Cam Designs
JRC Technologies Group
Denver, NC
(704)489-2449
www.jonescams.com

So, the profile in question has a .313" lobe lift.
It's one of more mild in his selection.

 

I wouldn't call a magnum lobe lazy it just has a slower ramp at very low lifts. Personally I have run alot of cams and the XE and XFI grinds are garbage they will eat your valvetrain as well as the cam and lifters in no time.

 

XFI exhibit 1

XE exhibit 1

By comparison to the XE/XFI lobes the Magnum/Rhoads combination is much quieter. You do not hear the valvetrain at 60+ mph. Sounds like a well oiled sewing machine at idle comparred to the harsh metal on metal clacking of the other lobes.

 

I've never had an issue with the XE cams. I've run the XR 276 and the XR288 with no issues, plenty of RPM and lots of mileage. Keep in mind that this is with a lightweight spring and retainer (COMP Beehives and tool steel retainers).
The XFI lobes though, I found were noisy and probably harder on parts as a result.

 

My 350 wipped a XE 4x4 lobe roller cam running low mileage factory GM lifters. Had 787s and Pac 1218 Beehives.

 

Skinny,
Wow. Thanks for that Mike Jones info!

 

Wrong link!!

Except it is 112 LSA. 4° changes alot on the exhaust side.

they make it on 110. Summit link is wrong sorry
https://www.howardscams.com/hydrauli...cams-180235-10

180235-10!!!
Fgures summit is out of stock but would be shipped from howards eventually lol

I doubt you’d see much difference in 4 deg. Every cam i ever seen in just about any combination makes more with exhaust split, just have to time it right. Case in point, look at any ls truck cam like truck norris. Its 212/22x on a 107. Its one of the better trque cams.

 

Do you know the lobe profile number on that? I'm curious as to it's lobe lift and duration/lift values.

 

That's not a bad choice either. Except for the not in stock part.
Seems to be the way these days.

 

A little follow up to that earlier email.

Hi Mike.
Thanks again.I suspect he'll be in touch.
I'm assuming you have cores in stock.
Kevin
Mike's reply:

Actually, we are back-ordered on the OEM roller block cores(stepped nose for cam retaining plate).I don't know when we will have them.
Since he's wanting a cam on the smaller side, we could regrind his existing cam, and that would save him time and money.

Mike Jones
Jones Cam Designs
JRC Technologies Group
Denver, NC
(704)489-2449
www.jonescams.com

 

Skinny,
Thanks for the Mike Jones email update.

What do you think of this? Actually available.

Howard’s # 108225-10
207/213, .300”/.310” lobes, 110 LSA, 106 ICL
.020 239
.200 125
Not positive about listing the last specs.

 

Are you sure about the part number?
I can find a 110225-10 but not a 108225-10.
Then again, I searching with my phone...

 

Skinny, False alarm, sorry.

You’re right. Howard’s guy misspoke.
108225-TWELVE!

No such thing as a 108225-10. Called back, also couldn’t find it on their site.
Back to the drawing board,
unless the Howard’s 108235-10 isn’t too soft on the low end with my combination.

 

I dare say that the 108235-10 might be a step up from the Magnum 270. Slightly earlier IVC (as near as I can tell) and a more progressive lobe. I haven't got the opportunity to compare it directly with the other cams in question as I don't have access to my PC. But for my own curiosity, if nothing else, I'd like to crunch some numbers later.
Maybe Fast or Orr or BadSS have an opinion on this latest possibility.

 

I dont see how it would be too big. I think it would work. Me, I think nitpicking over a few deg here and there, few deg of lsa here and there, in the end is just wasting time and overthinking it. Imo. You can try 10 cams of similar specs and maybe only see 5-10 hp. Granted some may def show more off idle response. Its hard to tell just by looking at it. All the programs can show trends and all cam experts can say what they think can happen but you really need to test to know. But who buys multiple cams for a driver like this?

you gotta decide. Of the cams available right now, given the nature of the supply chain, do you need a cam right now today? If not can you wait it out? If you dont mind waiting, would you go for a custom grind cam? Get what you really want or live with the best alternative that you can find available
not the best time to be building cars, everything is way more expensive than few yrs ago and not much is in stock

 

I can agree with you on all points there Orr. Matter of fact I was going to make a comment on the few degrees here and there myself.
That said, not having a world of experience testing on the dyno for one engine flog, the best I can do is compare cams on paper. Then solicit opinions like yours, so any answer given will at least have some thought behind it. I was called out here so I'm doing my due diligence.

A quick word on my take on DCR too. I like to use it for my style of build because my builds aren't over the top. The dynamics that go behind a maximum effort deal while present in the lesser effort aren't as influential as they might be behind a Pro Stock engine. You've discussed that more than once with respect to things like cylinder filling and port design, et al. To me, the calculated DCR can give a reasonable indication of how the engine might behave in one respect or another. If you told me 6:1 in a NA SBC, I'd say to rethink it. If you said, 9:1, I'd have questions as to how it would work.
Anyway...
Waiting is the operative word here. A custom grind would be the top of the list but then we go back to the few degrees here and there so maybe a readily available shelf grind is the way to go.
What I don't want to have happen is whatever gets spec'd, doesn't produce the low end pop the Mortorq is looking for.

 

Im not calling anyone out just stating imo i dont think a few degs on a lobe is gonna totally kill the combo. I just havent seen it at the local dyno on the latemodel cars. I know different platforms and usage but trends are formed.
And DCR is a nice tool to have, as a guideline to establish a baseline combo. Engine dynamics has a lot of variables and we work with simplified tools to make it easier to get somewhere. Same thing vizard has done with his empirical testing and correlating variables to results. I mean thats why big block has different formula than small block for cam spec. They both work the same way, and are pretty similar in design architecture but the little differences they do have end up changing some correlations.

 

Sorry Orr. I didn't mean that to imply you called me out. I was referring to Mortorq calling on both of us for an opinion. I can see how that was confusing.
As for the rest, yes, baseline for some kind of reasonable comparison. Once that's established, I'd be straight to the dyno. But it's not likely I'll get to one (but I would like to get the 357 one if for no other reason than to prove the theory).
Now, you mentioned Vizard and that's part of the "theory" I work with. If he has a few hundred thousand dyno pulls to draw from, who am I to argue.
I've said before, I prefer to stand on the shoulders of giants and those that have been there before.

 

Why does a 305 not like more duration on the exhaust side? Would it be any different for a 350?...

 

Same exhaust port and valve size as an equivalent 350 head and a smaller cylinder. It simply does not need the added exhaust duration. All the added duration will do is make it soggy on the low-end.

 

I’d like to provide more input, but don't think I could help much considering everything I’ve ever built, any cam that I’ve ever swapped, and anything I’ve ever tuned on was using 92-octane or racing fuel. I could provide first hand experiences of the 10-12 difference cams I installed in LG4s and L69s back in the mid-80 and early-90s, but all had automatic transmissions except for one and all were tuned running 92-octane. So, I have NO idea if they would run OK on 87-octane.

 

Interesting point.
I'd inquired about the OP's exhaust setup but don't recall getting a reply.
If it's shorty headers and a 2-1/2" Y-pipe, is a few degrees on the exhaust side a benefit?
That seems to be the case when more CID is involved but I can't speak for the 305.

 

I'm not too far removed from that myself. For whatever reason I always worked towards the edge of the street/pump gas tuning envelope.
This is why, when breaking down the OP's combination, that I keep going back to whether or not any recommendation would survive on lesser grade fuel.
As was suggested earlier though, in an exchange between Orr and myself, at what point are we splitting hairs?

 

I am in the same boat. Trying to decide what will run on 87. I find even running stock engines on 91 or 93 worth it. The factory engines are detuned to run on 87. For example a stock Vortec 305 or 350 only has 22-24° of timing programmed into it to run on 87. They make best power on 30-32° total timing and a much quicker advance curve. My L31s fuel consumption decreased enough on 91+ to even out the cost difference and then some. Why they even make 87 is a mystery to me. A gasoline engine can be much more efficient on 91 or 93 octane.

 

My 350 with a tiny 203/210 @ 0.050 on a 110 LSA cam was a DOG on the stock GM timing table. I put a much hotter advance curve on 91+ fuel and it really woke it up compared to the stock timing. It made alot more torque, the engine made power to a higher rpm, the engine ran cooler, it jumped up 2-3 mpg average, and also less carbon buildup. 87 has been a waste of time for me short of my lawnmower, edger or generator.

Stock timing table, was having to run 89 anyway since it spark knocked enough on 87 for the knock sensor to retard the timing on 87 even bone stock.
https://youtu.be/2CqkRkABKk4

91 Octane with a much hotter advance curve.
https://youtu.be/yXTXqMCkF34

Same exact setup, hotter timing curve knocked ~3 seconds off the 0-80.

 

Guys, you have covered a lot of ground here, thank you, sure is helpful.

Since in-stock choices would be kind of a compromise, would the still-available HT383 “395” cam be an improvement over the factory TBI peanut cam, since everything in my spec range from the aftermarket manufacturers are back ordered until at least October-if then?

The ‘395 cam has 17 more intake and 12 degrees more duration @ .050” with the same nice 109LSA.

Would you clearance the push rod holes and use stamped, guided, 1.6 rockers?

(Street use, carb’d L03, Holley 600 mech sec, #520 305 58cc Vortec heads valve guide bosses clearanced for higher lift, beehive springs, Performer, HEI, Mallory 4309, Hooker 2055’s, full Aerochamber exhaust, 3:08 posi, T5)

 

In a 350 that cam responded well to 1.7 rockers. 1.6s would work on a 305 to keep things simple. That is the cam used in the marine 305s to make 260-280 hp. Its a slight improvement compared to the L03 cam, but a stock F/Y LT1 cam is hotter.

 

That cam has 288 degrees of seat timing on the intake and with
196 @ .050" it's lazier than the Elgin posted earlier.
With 288/306 on a 109 LSA the overlap is 79 degrees. It would a torque killer in my opinion.
I can see it being a decent marine cam because it would be gentle on a valvetrain that's being stressed continuously but everything about it says to stay clear for a 305.
I will say that I haven't got much to say about any of the OEM cams. While they produce power no doubt, their design is such that they last and don't beat up parts. But there's a lot.of room for improvement and still have your valvetrain last.

 

GMs advertised duration is off zero lift points so it is way longer. A stock L03 cam is something like 275° where the old L82 cam is 346°.

Edit-Found an old post I had read. 395' cam was measured 250/264 @ 0.06.

https://67-72chevytrucks.com/vboard/showthread.php?t=255659

 

Now THAT makes a lot more sense.
There's that apples to oranges lift point thing again.
Crazy *** duration split.
Do you trust the .050" numbers posted?

 

Geez
Thanks again for your expertise & saving me from myself with the alternate choice 395 Ramjet cams real personality.
Better wait for October for all the back ordered aftermarket cams to finally be ground.

 

FWIW the stock L03 cam is 244/259 @ 0.06.

 

Pretty close to what I found. Mine sat in the L31 5° advanced with the stock L31 single roller timing set. Had a very high DCR. Was definately torquier than a stock L31 cam but had a tendency to spark knock at 9.6:1.

 

Well, it's not as bad as my initial knee jerk reaction made it out to be.
That said, I think we've discussed better choices.
Remember what Mike Jones about having an OEM core reground. You may be able to give a shout out here and see if someone has a stepped nose cam for sale on the cheap.

 

Definately not a torque killer. Gave my 9.5 14 bolt 3.73 G80 a work out with the 4L85E and stock 4.3L converter that stalled 2,500 rpm. It would break 295/50 R15s loose from a stop and nearly half of my vans 6,200 lbs is on the back tires. On E85 it made 330 rwtq @ 2,900 and 272 rwhp @ 4,700 with cast iron vortecs that had 2.02/1.60 valves, 0.016 compressed head gaskets and 1.7 roller rockers. Its just done at ~5,000 rpm and I was shifting at 5,100 right before the power nose dived.

 

Getting the .006" duration specs puts a different perspective on that cam.
I'd like to build a spread sheet for all the cams in question to see what's where. That'll be a few days out though.

Fast. The video above, what's the CID?

FTR, E85 allows you add a ton of timing correct?

 

14 deg split at .006. 8 deg at .050. A few deg exhaust duration doesnt always hurt

 

Not to threadjack, but what would be the effect of a longer duration on the exhaust side with exhaust manifolds versus headers? Obviously headers will flow better, but would a longer exhaust duration (like 6 degrees more than the intake) help to crutch the restriction of exhaust manifolds, or would there be no real benefit at all?...