Cam & engine gurus gtf in her meow!

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yep harold designed that xe268 comp and the others in that series
we sold a lot of them
I just did not sell them for MOPARS
that extra 5-6 degrees at 200 helps send those chevies to their trailer
never give a sucker an even break W.C. Fields
 
Hi Truo my experience went with a Racer Brown cam for a stock 79 360 was a EH-71 it is 262 ,214 , 450 lift ,108 cl in at 105 the int.is 105 and ex.111 this is in a 65 Barracuda 4 speed with 3.55 but what sold me is a friend bought one for his 82 1/2 ton 360 stock but has a performer intake with a Thermoquad carb and dual exhaust with 2.94gears has great towing which he uses it for beside driver, plenty of bottom end , good mileage and does 15.90 in the quarter. Funny thing he made more money that day with truck than his race car. Cam was only 160/ lifters 60 if my young brain can remember lol my 2 cents
 
1965barr said:
Hi Truo my experience went with a Racer Brown cam for a stock 79 360 was a EH-71 it is 262 ,214 , 450 lift ,108 cl in at 105 the int.is 105 and ex.111 this is in a 65 Barracuda 4 speed with 3.55 but what sold me is a friend bought one for his 82 1/2 ton 360 stock but has a performer intake with a Thermoquad carb and dual exhaust with 2.94gears has great towing which he uses it for beside driver, plenty of bottom end , good mileage and does 15.90 in the quarter. Funny thing he made more money that day with truck than his race car. Cam was only 160/ lifters 60 if my young brain can remember lol my 2 cents
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2.94 good for towing, maybe if going down hill.
 
WYRMRIDER....Can you clean out your inbox ?
Would like to send you a PM. Thanks
 
Hi guys, so im back.

I'm still very interested in swapping in a very mild cam into my truck.

Like I said from the get go. I want mild performance. I'm not looking to build anything high performance. I just want something slightly better.

Yes I will look at getting a convertor and gears for it down the road. But for now since I will be swapping in the intake and carb id like to do the cam as well.

Or better yet help me figure out where I need to start first.
 
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So I have this exact camshaft in my '00 Ram 1500 4x4 with a 5 speed. In all honesty, it is a touch big for this application, but it is by no means gutless. I did deck the block and shave the heads for a bit more compression in the 5.9 Magnum. If I could go back, I would have dropped the duration @ .050" by about 10*. If I were you, look at a camshaft with 210 ish duration and a tighter LSA (like 108) if you want lope but don't want it to be a pooch off the line.
 
If you don’t want to lose anything off the bottom, this cam is a good choice. Should see some improvement across the full power band. Use it with an Edelbrock Performer port matched to a Fel-Pro 1213 head gasket along with the carburetor of your choice and be happy.
Mopar Hydraulic Flat Tappet Camshaft - Camshafts
 
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WTruo said:
Or better yet help me figure out where I need to start first.
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you said
WTruo said:
I'm not trying to build a hot rod. All I want is a throaty sound.
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WTruo said:
I don't want a performance engine right now. I just want a choppy idle sound.
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Now you say
WTruo said:
Like I said from the get go. I want mild performance. I'm not looking to build anything high performance. I just want something slightly better.
Click to expand...

On the off chance that you get it figured out what you actually want; then, with your current combo,
First;
is
convertor and a free-flowing exhaust.
Check out this graph; even tho it might be similar to your low-compression 360, don't look at the absolute numbers. Instead look at the shape, and the percent differences.
If your current stall is 2000, then on this graph that looks like ~105hp
By 2800 it looks to be ~155hp;
So ; that is an increase of 50%!
where would you rather be?


There is no one single thing you can do to your engine, besides Supercharging, or race gears, that can give you this kind of off-the-line boost.
At ZERO to ~20mph, this is a performance increase similar to;
a cam one size (or maybe even two sizes) bigger,
WITH an accompanying compression boost to say 160psi,
AND headers.
AND a 4bbl/intake,
all wrapped up together.

Check out what happens at 3200 on this graph: Max torque is what happens.
If you stall your engine at or slightly lower than peak torque,yur gonna need;
bigger tires,
a SureGrip,
and some kind of pinion snubber to eliminate wheel-hop. Yes, even with 3.21s/ go back to post #8

But if in fact, all you want is a rumpidy-rump idle, then that was covered on page 1.
and specifically by Rumblefish.
But be advised, if that will be your only change, then prepare for nearly zero performance increase below ~20mpg, with a very real possibility of actually losing performance.


power-318.gif
 
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WTruo said:
I don't want a performance engine right now. I just want a choppy idle sound.
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Then get a poser cam like a Thumper. All show and no go. They idle like a top fueler.
 
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toolmanmike said:
Then get a poser cam like a Thumper. All show and no go. They idle like a top fueler and smooth out around 2000 rpm.
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That sounds nice. But I think those are the cams a lot of people on here were crapping on. Not hating on your setup at all.
 
WTruo said:
Minimal performance, like a step up from stock. Maybe that's where I lost a lot of people?
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You don't want to loose your bottom end. That rpm range is where you spend 90% of your time. Idle to say 3000 rpm.
 
WTruo said:
That sounds nice. But I think those are the cams a lot of people on here were crapping on. Not hating on your setup at all.
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Not my set up just a random You tube video.
 
20200112_174542.jpg
20200112_160916.jpg
AJ/FormS said:
you said

Now you say

On the off chance that you get it figured out what you actually want; then, with your current combo,
First;
is
convertor and a free-flowing exhaust.
Check out this graph; even tho it might be similar to your low-compression 360, don't look at the absolute numbers. Instead look at the shape, and the percent differences.
If your current stall is 2000, then on this graph that looks like ~105hp
By 2800 it looks to be ~155hp;
So ; that is an increase of 50%!
where would you rather be?


There is no one single thing you can do to your engine, besides Supercharging, or race gears, that can give you this kind of off-the-line boost.
At ZERO to ~20mph, this is a performance increase similar to;
a cam one size (or maybe even two sizes) bigger,
WITH an accompanying compression boost to say 160psi,
AND headers.
AND a 4bbl/intake,
all wrapped up together.

Check out what happens at 3200 on this graph: Max torque is what happens.
If you stall your engine at or slightly lower than peak torque,yur gonna need;
bigger tires,
a SureGrip,
and some kind of pinion snubber to eliminate wheel-hop. Yes, even with 3.21s/ go back to post #8

But if in fact, all you want is a rumpidy-rump idle, then that was covered on page 1.
and specifically by Rumblefish.
But be advised, if that will be your only change, then prepare for nearly zero performance increase below ~20mpg, with a very real possibility of actually losing performance.


View attachment 1715625620
Click to expand...

I'm terrible with words and how to explain myself.

I already have the exhaust done. Headers, x pipe connected to dual mufflers.
 
Where you got lost was not knowing this;
At low rpm, your engine does not start to build compression until the intake valve is fully closed. Compression is what makes power.
If you install a "bigger cam" with a presumed to be later closing intake valve, your engine will make LESS pressure, which translates to an immediate loss of power, at low rpm.
Camshafts are sized about 6 to 8* apart, like;
250/256/262/268/276/284/292. The intake closing point on each of these is delayed about half the difference in size, or say 3.5 to 4 degrees. This moves the operating rpm up about 200rpm, and it is the improved efficiency at the new higher rpm that makes the power.
But to do that, the cam gives up pressure at low operating rpm. The loss is about 1.5 psi per degree. A low compression engine,with no other changes, will immediately get lazy down there.
That's NOT what you want, is it?
A Thumper/Whiplash type cam will drop a lotta lotta psi at idle. And won't start to get it back until you wind it up. That's all good if you have a high-stall TC.
So
since you need a hi-stall anyway,
You might as well start there.
And since a 4bbl and bigger cam, are gonna start processing more air, you need to get rid of that more exhaust.
And since in a lo-compression engine,the bigger cam won't wake up until higher up the rpm band, you will need more than 3.21s if you want to feel the cam.
Finally, that rumpity-rump you might hear at A&W comes atta price. That is the sound of low-efficiency at low rpm. Which is the opposite of street performance...... when married to a 3-gear TorqueFlite. You won't get that sound with one cam size. It takes about 45 degrees of overlap to introduce it, and it is not until 70 or more degrees to be really noticeable.

I can almost guarantee you that in your truck, with no other changes, you will hate driving it with a cam big enough to have such an idle.
I can almost guarantee you, that, with no other changes, you would love a 2800TC. You will slap the gas pedal almost every time you leave a stop.
For you, You might like the Thumper/Whiplash cam, but it won't be in there long before you will want a TC and most likely gears as well. And of course, the Whiplash wants headers, a free-flowing exhaust, and more cylinder pressure (pistons), to get the best out of it.
And for as long as it is in there, it will drink gas, like camel drinks water
 
Headers work in a couple of ways.
Firstly;
they create a lo-pressure pocket behind the exhaust valve, so that when it opens, the exhaust is desperate to leave the cylinder. This frees up some power that would have otherwise been used to push that exhaust out.
Secondly;
If your cam has significant overlap, such that both valves are open simultaneously at the changeover from exhaust stroke to intake stroke, the low-pressure in the primary pipes, will help the atmosphere push AF charge into the cylinder, before the piston is actually officially moving down on the intake stroke.
But this phenomenon does not happen until the rpm is up hi enough to get it started, usually in the early to mid 2000 rpms.
And it is most effective at some higher rpm to which the cam is tuned for, and over a fairly narrow rpm band say 1500 rpm or less.

So the gist of this points to headers working best from the torque peak to the power peak and beyond. How do you get there with 3.21s and I'll assume 28" tall tires?
Answer; slowly.
and with a bigger cam and still a nominal 8/1 compression ratio; probably slower than stock.
 
Wyrmrider said:
yep harold designed that xe268 comp and the others in that series
Click to expand...

I remember a discussion on SpeedTalk where Harold states he didn't design the XE range but the earlier HE series for Comp. Said the XE range were too fast on the exhaust side seating as opposed to his preferred style of seating the exhausts gradually in a comparative sense.
 
OP, all have giving decent advice, either exchange it for the next cam down, or use it and advance it about 6 degrees. It'll be decent ...or a dog if you put it in straight up or even 2 degrees adv.

engle cams is my go to, but any competent grinder can come up with something right for your truck.
 
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