Hughes heh237/242 in a 360?

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AJ/FormS said:
IMO
a lumpy idle is not an issue.
Rather; the "pumpgas compression 360",is a problem.
The lumpy cam usually points to a late-closing intakes, and a generous amount of overlap.
When coupled with the right cylinder pressure this can be a dynomite combo.
But when coupled with a ,what used to be called "pump gas friendly, compression ratio of 9.0 Scr or say even 9.5, it's a disaster off the line, requiring a higher stall, and un-street-friendly gears, just to get moving. Most times the combo doesn't wake up until well after 3000rpm.
So no, that won't work with 3.23s because 3000 is ~29mph; and who wants to wait that long! Even with 3.91s yur still waiting to ~24mph.
So if it don't spin, it's a total disappointment.
The only choice at that point is a higher stall, to get past that soft zone. And by this time there is no hope of comfortable hi-way cruising, and forget about fuel economy. So what you are left with is a Saturday-Night Cruise-in-and-park combo,with a race car personality.

The partial cure for this is more cylinder pressure, which usually involves more stroke, or more Scr, or really; just an earlier Ica.

Would I run that cam?
Well,
I ran the next bigger 292/292/108DC cam, with a clutch. That combo did not like 3.55s which is what I wanted to run. That cam was out and sold before the first winter. and
I currently run the next smaller Hughes cam, a 230/237/110 hydrocam. For me it is bordeline too big, and I have combo'ed it with 180 psi, a 4.10 equivalent starter gear, and an overdrive.It's a great combo, and has been in my car since summer of 2005.

The problem is the early exhaust opening. It gets terrible fuel economy, and blasts thru a tank of gas in a heartbeat. Even on the hiway in steady-state at 65=2240 and with over 50* of timing.( she likes more). A good portion of the expanding gas energy, goes straight out the exhaust.

Now; above is with a 230/237/110 cam@180psi, in a 367, with a clutch and 3.55s.
Imagine it with a 237/242/108 with 130psi cylinder pressure, an automatic, a 3000 stall and 3.91s, still with a 3.58 stroke. In at 104, the Ica is 66*(same as mine) and the exhaust opens at 104(advertized) same as mine. My overlap is 61*/60 effective. The 237 cam has 70*/64 effective. What this 237cam offers is about a 300 rpm higher power peak, so yeah more absolute power, but the rest is about same as mine. It's gonna need pressure, and it's gonna burn a lotta lotta gas.
Click to expand...
Low cylinder pressure that is what is going on with my 340- no low end torque.
Current cam is a Comp hydraulic roller @ .050 - 224/230, .538/.534, 110LSA in @ 106
 
512Stroker said:
Low cylinder pressure that is what is going on with my 340- no low end torque.
Current cam is a Comp hydraulic roller @ .050 - 224/230, .538/.534, 110LSA in @ 106
Click to expand...
I had a 223/230/110 similar lift (.538/[email protected]) in my 367 for ~4 years; I loved that cam. I'd still be running it today if it hadn't dropped lobes. But I ran it with Eddies and at 180+psi,lol.
That cam did everything for me. Well; it was a lil short of power in 4th gear, but so what; with 3.55s, 6000 in third is about 100mph,so I didn't miss what I didn't know that I didn't have.lol.
It had a tremendous mid-range, and
with a double overdrive, it returned some pretty incredible fuel mileage.
It was just an all around great street cam.
 
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fishy68 said:
That's the cam I put in my 408 when I built it but didn't get to run it because when I pulled the valve covers to install the inner springs I found one of the lobes going flat. The only thing I can say is it was lumpy but not radical idle in my 408, for the few minutes I ran it before discovering the problem. As far as any cam being too lumpy for street use, that's all up to personal taste. We do cruise-ins every summer weekend and some of the stuff I see guys drive on a regular basis is insane IMO. But their ok with it
Click to expand...

Like this???? Lol

 
512Stroker said:
Low cylinder pressure that is what is going on with my 340- no low end torque.
Current cam is a Comp hydraulic roller @ .050 - 224/230, .538/.534, 110LSA in @ 106
Click to expand...
I run that cam now in the wife’s car. Give it some compression or add a centrifugal supercharger.
 
512Stroker said:
Interesting
I cant find the spec's on ST-36
Say HI to Uncle Joe for me.
Click to expand...
It's been 8 yrs. so maybe I'm remembering the grind # wrong. It's 266/266 advertised, 236/236 at .050". Lift before lash is .517 using 1.6 rocker arms. 108 lca.. Real nice mild street cam that is just a little lumpy and pulls good to 5500 in a 408. Torque is fantastic
 
rumblefish360 said:
I run that cam now in the wife’s car. Give it some compression or add a centrifugal supercharger.
Click to expand...
With 3:23 gearing and a stock converter it was a real slug out of the hole.
After alot of tuning 3:55 gearing and a 3000 stall TC it hole shots very well and pulls like freight train up to around 6 grand. I have been thinking about adding another fuel tank in the trunk LOL
 
512Stroker said:
I have been thinking about adding another fuel tank in the trunk LOL
Click to expand...
That ain't the [email protected] cam! sucking your tank dry!
Nor in the 3.55s by themselves.
I installed an A833-overdrive behind my 367 and a GVod behind that, which I used as a gearsplitter; and double od on the hiway.
With 3.23s and 28s it was was 65=1400
With 3.55s and 27s;, 65= a tic under 1600.
That 223/230/110 (270/276 advertised), cam easily pulled that, and with accompanying timing changes, pulled mpgs deep into the 20s USg.

At 180/185psi cylinder pressure, and 3.55s and a 3.09 low gear, that combo was a dump it and go deal. I mean with just a lil blip on the throttle, the flywheel unloaded into the 10.97 starter gear, and the car pulled away very nicely.

I eventually got rid of the overdrive A833, in favor of a Commando box, which also has a 3.09 low gear.

People say cylinder pressure ain't all that big a deal. That has not been my experience.
People say Quench ain't that big a deal. That has not been my experience either.
In my experience;
alloy heads, tight Q, and 180 plus psi, with accompanying timing changes, makes a chitload of torque from idle to shift rpm. I tell you a truth, I had so much bottom end, I could not use it all in first gear without tirespin. Granted the tires were 295/50-15 BFG-TAs, but they spun anywhere in the rpm band from just above idle to 4000rpm (the highest I had tried; which is 47mph in second gear), with just a footstomp (750DP).
BTW, I revved that puppy to 7000/7200, and she went 106 in the Quarter doing that, @12.9 seconds, spinning street tires until third gear with the 3.55s. IIRC that mightabin with 245/60-15s.
It is a great street cam.
If you map it out you will find that using the advertised specs; power duration plus exhaust duration comes to 227degrees. This is a good number for a street cam. In at 106, that is 119* to compression and 108* to power; both are reasonable numbers.
But with a 360 I ran it at 110/straight up, changing that 119 to 115, and the 108 power to 112. That's one of the benefits of having a preponderance of torque; you can give some up.
And at 112* power extraction is the beginning of fuel economy.

You may know the following, IDK; but to save someone else from this lack of bottom end thingy, caused by lack of pressure; I thought it would be worth mentioning.

Here is a comparo;
First; my 4.04x3.58=367 combo,
Static compression ratio of 10.8:1.
in at 106*/ 930 ft elevation
Effective stroke is 2.86 inches.
Your dynamic compression ratio is 8.83:1 .
Your dynamic cranking pressure is........... 181
V/P (Volume to Pressure Index) is ...........159

and retarding the cam;
Static compression ratio of 10.8:1.
in at 110*/930ft
Effective stroke is 2.77 inches.
Your dynamic compression ratio is 8.58:1 .
Your dynamic cranking pressure is............. 174
V/P (Volume to Pressure Index) is............. 148
Notice I gave up 11 points of VP, and 7psi cylinder pressure, to get ~200 operating rpm at the top.


Second; in a 340; 4.04x3.315=340
Static compression ratio of 10.8:1.
in at 106/930ft
Effective stroke is 2.64 inches.
Your dynamic compression ratio is 8.80:1 .
Your dynamic cranking pressure is .............180
V/P (Volume to Pressure Index) is .......146
Notice at the same install of 106*, both engines are making about the same 180/181 psi. But
notice the change in VP, which is a performance measure that can be used to compare the bottom ends of various engines and cam installs.
Read about VP here; V/P Index Calculation
it drops from 159 to 146; why is that?
Both engines are at 4.04 bore, and both are at 10.8Scr; so the difference has to be in the stroke. Notice the effective strokes; 2.86 in the 367, to 2.64 in the 340.

Ok so now, lets reduce the Scr of the 340, to burn pumpgas
Static compression ratio of 9.8:1.
Still in at 106/930 ft
Effective stroke is 2.64 inches.
Your dynamic compression ratio is 8.01:1 .
Your dynamic cranking pressure is.............. 159 see note1
V/P (Volume to Pressure Index) is ............. 129
Ouch!, you see the new VP of 129? That is about what a good 5.2 Magnum puts out. and so that is what a 340 with this combo, will feel like, as to bottom end. And that is why you need the 3000TC to get moving.


Note1;
with iron heads;
160 psi is pushing the detonation limit with open chambers
165 psi is about tops for a tight-Q design, and 91 octane. unless you are YR, then;
170 or so is for a pro-built combo

with alloys, and tight-Q
170 is nothing
185 is still on 87E10; been doing it since 1999
200 is what some guys on FABO have reported, still on pump gas, but requires careful timing.
__________________________________
My Chevy Orlando Direct Injected VVT 2.4liter 6 speed,2500TC, pumps 220 psi and runs 87E10; and makes 167hp at 6700 on that; Yippee! Boy you can really feel that VVT kick in at 4500,lol. Truthfully, I have never found that Orlando to be underpowered; and I rarely venture into the 4500 Plus arena. I'm guessing the gears have a lot to do with it.
vroom, vroom, vroom, vroom, vroom, vroom, 6 gears; and into 3rd by 40/50 clicks Wahoo!
 
@AJ/FormS

GREAT POST!

The only drawback is most of us can not afford a GV OD set up (or want to or install one) BUT it shows the value of the final drive ratio or at least the RPM’s turning which is a key in your mileage.
But the way, what’s deep in the 20’s for mileage?
 
rumblefish360 said:
But the way, what’s deep in the 20’s for mileage?
Click to expand...
Rob are you goading me again,lol.

That GVod has paid for itself a long long time ago; both in fuel savings and less engine wear and tear.
That car has had 3.55s most of it's life. And before overdrive, the hiway rpm was 2870, compared to 2240 after. That means with overdrive, the engine turns 630 fewer revolutions per mile. Over the past 100,000 miles that totals a whole big bunch of less wear and tear, less maintenance, and less fuel burned. Add that to the fact that she burns 87E10 100% of the time, for even more savings. Every time I get into that car, I figure it's paying me to drive her,lol.

As to fuel mileage;
With double overdrive and geared 65=1590, over a distance of 602 km/ 372 miles of steady-state driving, My Barracuda S clone, consumed less than a tankful of gas. I brought along my own Manitoba gas, and took pains to be accurate. Point to point, from my hometown to St Cloud Minnesota, she used 42 liters ,or 9.2 gallons Canadian, or 11.5 gallons US. and
372 miles/11.5g=32 mpgUS.
The only things different from it's street tune, was the 600Holley model 1850 on top, that had previously been modified to run lean, and the dial-back timing device had been reset to be able to crank, what I thought was, ridiculously much timing into the program.
In the trunk, was the 750DP, and as soon as we pulled into the fairgrounds, the 600 swapped ends, and I think we burned more gas in the next two days just driving around, than that which we burned to get there,lol.
The plan for the trip home was the same. But just North of Minneapolis , a red Corvette came screaming past us........ so, since it was late in the day, I stayed with him for a few hours until it got dark; and then we stopped for sleep.
Trick question; if 65=1590, how much is 2900?
So forget fuel mileage coming home
 
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No sir, no goading. I don't believe 32 mpg's though!

But your post was really good my man.
 
FWIW.. At a steady 65 mph in flat midwestern country like where AJ dwells, I would 100% for sure get 29 mpg in my '76 Dart Lite /6 with the 4 speed OD, and 2.76 rear axle. Stock from the factory, never touched or optimized; though they did have a lean carb setup in there. No idea of the RPM's but it had to be down there like AJ's. And a '76 Dart was not exactly an aerodynamic marvel LOL.

Almost forgot: My '09 Challenger 6 speed OD manual will get 28 mpg at 65 mph in flat country..... every day of the week. Bigger engine than the Dart Lite, so more pumping losses, but the aero is a lot better.

10% or 12% more MPG from those 2 pure factory efforts would be 32 mpg and so is within reach if the engine and drivetrain are set up to be highly efficient and the aerodynamics are good. Tweak the timing for fuel MPG and so on.... certainly sounds doable. I bet if we all read up on the fuel mileage challenges held over the years, we would be impressed.
 
The biggest issue is giving the engine the timing it wants a those low rpms.
It is IMPOSSIBLE to satisfy the engine at those low rpms, without a timing computer, and that is why everybody jumps on the "impossible" response.
Just try it for yourself; rev your SBM engine up to 2000, and start feeding it timing while simultaneously keeping the Rs to 2000. When the engine no longer picks up rpm, you have reached it's happy spot. Now put the light on it and tell me what you got; I bet it will be in the mid 50s.
Now; how are you gonna meet that need, and still have correct power-timing to fall back on? It cannot be done.
Your Power-timing at 2000 with a manual trans, to run 87E10, in an 11/1 Eddie-headed 367 will need to be limited to around 20 to 24. If you mod your Vcan to the max, you might find 22 to 24 Degrees, for a total of 42 to 48. You are still 6 to 16 degrees short. And so you light the fire too late and it chases the piston down, wasting energy. The lower your cylinder pressure, the worse it is.
On this trip, with the dial-back timing device, I had a 63degree max possible timing, at 2000 rpm.
So; just because my combo got 32 on that particular trip, doesn't mean yours can. And it doesn't mean mine can't do even better; I just slapped together what I had.

Here's the back-up math;
At 64mph,32mpg will require 2 gallons, which is ~12 pounds of fuel.
At WOT the rule of thumb is that your engine requires about .5 pound of fuel per horsepower per hour. Therefore 12/.5=24 hp; that sounds pretty close already.
But how lean can you run it at a steady 1600? IDK, I had no AFR on it.
Suppose I could run .375 pound of fuel per hp per hour.
That would be 12/.375=32hp, that sounds really close.
 
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Truly the trick is not to waste any of the fuel and burn it all. Since we do not have a computer to control everything, compromises are made everywhere. Experiment and do the best you can.
 
rumblefish360 said:
Truly the trick is not to waste any of the fuel and burn it all. Since we do not have a computer to control everything, compromises are made everywhere. Experiment and do the best you can.
Click to expand...
Yep, and the aero package at that 65 mph is a big factor since wind resistance has grown very large at those speeds compared to rolling and drivetrain resistance. Manual trannies also have an advantage over old non-locking TC slushboxes for efficiency.

I rented a new Ford Expedition for a week in late 2018 in the northern Rockies and the 2.7L 4 cylinder, 10 speed auto moved that big cinder block 1500+ miles all around western Wyoming and SW Montana for a week, with an average MPG of 21 or 22 mph. It would get up to 24-25 at 70+ in the interstates, even with the hills.
 
Just checked my 14, 15.7, the computer in the dash showed 18.1. LOL
 
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