Street 360 W/.528" P.S. Cam

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RAMM

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This project has been a long time coming to completion but here we are. It is a very straight forward 360 w/ J heads w/no real work other than a good valve job and resurfacing , positive seals etc... 1.88"/1.60" valves? I didn't do them or take them apart as they were very fresh. The bottom end is just a 4.030" KB 107 piston, W Magnum Rods/ARP bolts, balanced and an old new Mopar .528" SFT with a Holley Strip SP. The customer supplied nearly everything including the 273 iron rockers and banana groove shafts.

Broke it in today for 20 minutes with Joe Gibs 15W50 BR oil, locked out timing @ 37* and the same GB 650 I used a week ago on the 408. It ran excellent and sounded nasty compared to the 408 on account of the 9" of idle vac. Pulled it numerous times on Esso 91 and 34-35* was best with no spacer other than the dumb little steel "gasket" you have to use to seal up a square bore to a spread bore. Yes it was very rich but like the 408 this is not the customers carb and I am only verifying the engine makes the expected power and doesn't leak/smoke/make bad noises or act weird. Could I jet it and change the oil to a thinner Vr1 10w30 and make more power? Yes I'm sure it would respond. Could I spend excessive time exploring carb spacers and lash loops/timing loops and gain more? Yes likely, only to find out the customer doesn't have hood clearance for anything more than a .062" carb gasket. I did spend some time checking / adjusting lash and more time again setting up a dial indicator and measuring valve lift on all valves (.498"-.509") and then compression testing all cylinders (175 psi). All in all this engine is healthy with great 50 psi oil @ 180* oil/water @ 900rpm and 380hp/390tq. It should move the 1st gen Dakota just fine I would imagine. Just sharing another SBM build that contains ZERO exotic parts or porting and what to expect. J.Rob

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20230908_174051.jpg
 
Little 340 we did, unported eddy heads, rpm intake, kinda small .470 lift Racer Brown solid cam, 9.7:1, 750 carb...

 
RAMM said:
This project has been a long time coming to completion but here we are. It is a very straight forward 360 w/ J heads w/no real work other than a good valve job and resurfacing , positive seals etc... 1.88"/1.60" valves? I didn't do them or take them apart as they were very fresh. The bottom end is just a 4.030" KB 107 piston, W Magnum Rods/ARP bolts, balanced and an old new Mopar .528" SFT with a Holley Strip SP. The customer supplied nearly everything including the 273 iron rockers and banana groove shafts.

Broke it in today for 20 minutes with Joe Gibs 15W50 BR oil, locked out timing @ 37* and the same GB 650 I used a week ago on the 408. It ran excellent and sounded nasty compared to the 408 on account of the 9" of idle vac. Pulled it numerous times on Esso 91 and 34-35* was best with no spacer other than the dumb little steel "gasket" you have to use to seal up a square bore to a spread bore. Yes it was very rich but like the 408 this is not the customers carb and I am only verifying the engine makes the expected power and doesn't leak/smoke/make bad noises or act weird. Could I jet it and change the oil to a thinner Vr1 10w30 and make more power? Yes I'm sure it would respond. Could I spend excessive time exploring carb spacers and lash loops/timing loops and gain more? Yes likely, only to find out the customer doesn't have hood clearance for anything more than a .062" carb gasket. I did spend some time checking / adjusting lash and more time again setting up a dial indicator and measuring valve lift on all valves (.498"-.509") and then compression testing all cylinders (175 psi). All in all this engine is healthy with great 50 psi oil @ 180* oil/water @ 900rpm and 380hp/390tq. It should move the 1st gen Dakota just fine I would imagine. Just sharing another SBM build that contains ZERO exotic parts or porting and what to expect. J.Rob

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Good power with stock heads!
 
Good stuff yall, thanks for sharing.
 
I have 241/241 @ 050, 112 LSA for the 528 cam. Would be leaving some power on the table with the wide LSA.
 
Bewy said:
I have 241/241 @ 050, 112 LSA for the 528 cam. Would be leaving some power on the table with the wide LSA.
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I disagree. It just puts the power in a different place.
 
RustyRatRod said:
I disagree. It just puts the power in a different place.
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In this case I agree with @Bewy . This is a good example of a mismatched combination. Compare the power curves with the 408 I tested last week. This only peaked 500 rpm higher with 43 cubes less and pretty much the same heads with a cam with 2 deg more LSA and 17 deg more @ .050" and a decent single plane intake. Conventional wisdom would have us believe this engine should have peaked much much higher than the 408 did.

Since the heads on this 360 are very very limited it could have capitalized on a milder cam with a 110-108 LSA, and RPM style intake and probably made 30-35 more ft/lbs 15-20 more HP @ the same peak and had a better idle to boot. In fact I know it would have as I have built 360's in this manner many times before. I'm not surprised this one didn't break 400 ft/lbs easily. I love solid flat tappet cams but I have NEVER seen the .528" whether it be in a B or an A engine work very well. This cam NEEDS great cylinder heads to make it look even remotely good. I'll probably get flamed for this but I believe the .484" hydraulic P.S. (or is it P.O.S.?) works better than the .528 J.Rob
 
Food for thought:

Shout out to Mike Jones 2!!

"I just got back from spending 2 days in Paris TN dynoing engines. One was my 1970 LT1 Super Stock engine.

Mike did a cam for it was we totally went against the "norm." It was a 55 tool steel, less duration, more rocker, and way wider LSA...

Some folks I knew were worried about no torque, etc..

With out giving too much away, I had more power at 6000 and 8000 than I did with engine 1 at peak. It peaked at 7400 and flat as Kansas. I have 46 more HP at 7500 than I had."

Edit: Chad Speier Racing heads. Not me!

Me: I'd take cam advice from Mike Jones before I ever listen to Vizard and his 128 theory.....
 
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@RAMM - POS

@Hysteric Its all about the combination of parts and timing of events.

IIRC, DV has stated that formula for street strip, not racing.
 
I realize it isn’t going to happen, but that looks like a prime candidate to show off the effects of what happens when you install 2.02 valves along with some properly applied bowl porting(220-230cfm).
Then, maybe add a more modern tight lash cam design with a more “correct” lsa.
 
Hysteric said:
Food for thought:

Shout out to Mike Jones 2!!

I just got back from spending 2 days in Paris TN dynoing engines. One was my 1970 LT1 Super Stock engine.

Mike did a cam for it was we totally went against the "norm." It was a 55 tool steel, less duration, more rocker, and way wider LSA...

Some folks I knew were worried about no torque, etc..

With out giving too much away, I had more power at 6000 and 8000 than I did with engine 1 at peak. It peaked at 7400 and flat as Kansas. I have 46 more HP at 7500 than I had.

I'd take cam advice from Mike Jones before I ever listen to Vizard and his 128 theory.....
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I didn't realize you were a member here. Cool. J.Rob
 
rumblefish360 said:
IIRC, DV has stated that formula for street strip, not racing.
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That's his design philosophy. Of all the stuff I've read over on Speedtalk that Mike Jones has posted it appears to me he prefers to use a little less intake duration and spread the LSA to broaden the torque curve. If you listen to Chad Speier's engine on the dyno its very tame @ idle and yet it made more power everywhere. In a street or street/strip application on pump fuel that would be my approach. Less overlap equals less intake charge dilution by exhaust residual unless of course you need the heat of the leftover exhaust residual to help vaporize the mixture because you can't get it done after it leaves the carb or on the compression stroke because of too little compression or too late a IVC point for the compression to build and cylinder pressure.
RAMM said:
I didn't realize you were a member here. Cool. J.Rob
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I'm not Chad Speier. Just pointing out that there are different approaches to this stuff that gets results.
 
Hysteric said:
That's his design philosophy. Of all the stuff I've read over on Speedtalk that Mike Jones has posted it appears to me he prefers to use a little less intake duration and spread the LSA to broaden the torque curve. If you listen to Chad Speier's engine on the dyno it’s very tame @ idle and yet it made more power everywhere. In a street or street/strip application on pump fuel that would be my approach. Less overlap equals less intake charge dilution by exhaust residual unless of course you need the heat of the leftover exhaust residual to help vaporize the mixture because you can't get it done after it leaves the carb or on the compression stroke because of too little compression or too late a IVC point for the compression to build and cylinder pressure.
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Agreed.

Just pointing out that there are different approaches to this stuff that gets results.
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Agreed. It’s always good to see and learn things. Better if there were cam tests to compare notes with. Same engine, different cam. Etc….
 
More food for thought:

Vizard on 106* LSA vs 112* LSA in a BBC

All 9 pages of it: Here are the opening salvos'

Mike Jones:

"Pretend the story was written by someone you've never heard of.
How does it match what you've seen in the real world.

I've done many dyno tests were we change nothing but LSA, and then move each cam around to where it runs the best. I've come to different conclusions then David."

UDHarold:

"My opinion is that you should buy whatever Dave Vizard recommends, because you probably deserve it.......
Tell your cam man what LSA you want, and he will grind it for you.
This way, your car will run its' fastest.
However, I recommend everywhere from 107 to 118, just depending."

:rofl:
 
When you finish that thread read this one:

Head to head cam LSA comparison

Some notable replies:

1. Someone needs to alert all the NASCAR teams. They need to tighten up their LSA, so they can make real power.
:lol:


What a useless test.
The 2 plane manifold is holding the power back on the one test, and either the hydraulic rollers or the exhaust is holding the power back on the other test.

So all the test shows is that when your top-end power is restricted by the parts your running, you might as well put a tighter LSA cam in to pick the torque up.
Glad to see we're ll up to speed with the 1970's.
:lol:

2. The test was perfect for selling Comp cams to people that believe every thing they read. That's all it was good for.

If you're going to test the engine with a 2-plane manifold that'll restrict the peak power to 6,200, run a hydraulic roller that's designed for 6,200.

With that manifold, you should run a cam around 238/[email protected]" for a 6,200 power peak.
If they ran that test with that cam, it would make more overall power on a wider LSA. It would also be a lot more driveable then the cam they ran, and wouldn't need as much stall.

When you run an oversized cam, it'll normally like the tighter LSA.
Except for selling cams, the test was useless.

3. I'm just saying the test is a joke when they make statements like this:

" We've got a very clear demonstration of the advantages-namely a more usable powerband-of running a narrow LSA."

That's a rediculous blanket statement to make from this test.
There are many cases where that is flat-out false.

On this engine, with these parts, with these cam profiles, with this compression, and with this fuel, it liked a tighter LSA.
That's the only conclusion that can be drawn from this test(advertisement).
 
DV has parameters around his 128 rule & some of them require widening the LSA.

Somebody needs to tell Richard Holdener that his dyno testing on on LS engines [ about 8-12mths ago ] was wrong. Dyno must have been playing up......
The three LSAs tested [ I believe they were 108, 110, 114 ]; maybe somebody can link the test. The 108 made more power everywhere, with big gains in the low/midrange. Right where you want it for street car.
And the same for 3 identical Isky cams in a 350 Chev, identical except for LSA, 106, 108, 110. Yup the 110 made more peak hp. 3.4 hp to be exact. But it was down 24 ft/lbs through the average to 7000 rpm. Which would you rather have? I would post it but the writing is too small.
Crower must have missed the memo also, because they had street cams in the 70s with 105 LSA; Grind #32202 for a 440 is one of them.
Joe Sherman was quorted as saying he made more power when he tightened the LSA.

And poor old sig Erson didn't get the memo either because he claims tighter LSA ALWAYS makes more mid range. See below

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And the Brits also missed the memo with their little 4 cyl engines using 106 LSA [ some were tighter ].

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Notice the first cam in the post above has a smooth idle...even with 106 LSA. That is because the duration was reduced for the better idle, not the LSA widened. Something DV has said for a long time....see the middle paragraph, near the top.

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All that extra overlap is probably why you need 50 degrees of initial............
 
It is not 'extra' overlap if the engine is making the desired hp. It is the 'required' overlap.

The Leyland/Mini cams in post #19 are aftermarket cams.

Leyland made a variety of cams from mild to wild. Most were on 107.5 LSA, some were on 102.5 LSA. The smallest 230/230 adv duration was on 107.5 used in 850 & 998cc engines.
 
Bewy said:
It is not 'extra' overlap if the engine is making the desired hp. It is the 'required' overlap.
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So Mike Jones can spec a cam with less intake duration and spread the LSA and still carry the RPM and still make more power.......

Its 2023......Not the 1960's
 
With all the variables that go into an engine, air cleaner to oil pan and applications that run the full spectrum it's no wonder there are examples that support both sides and the middle.
 
looking on summit, the basic rpm range for this cam is 2800-7000. Winder why this motor has peak hp at 5500rpm even with a single plane intake…
 
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