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Hey Frank (sscam69)!!!

B

Bullitt

Guest
Hey Frank, you out there dude? Anyways, I want to know if you're still willing to do a few simulation runs on your Desktop Dyno for me? Let me know the run down of everything I need to send you. I want to play around with some compression ratios and of course, cam grinds. I'm trying to decide whether to go "all motor" or "blown cruiser." First, I'd like to send you one or two engine combos with proven numbers, so I can see what type of discrepancy there is between the computer and the real world. I'd really appreciate your help. :)

--Bullitt
 
R

rpounds

Guest
Bullitt . . . if you can't get ahold of Frank, send me the dope and I'll run it through mine.

Ron
 

Yoda

Well-known member
Administrator
Joined
Oct 12, 2000
Messages
4,884
Location
Amarillo, TX
Corvette
1981 UL5
Bullitt ~ Check out the "Tools" tab at the top of the page, it may have a little of what you are looking for ;)
 
B

Bullitt

Guest
Test 1,2....

Thanks for the offer, Ron! Run this combo and see what you get. The dyno chart I have on this motor is ancient, but it's the only thing I have to compare to. It had injection with an Accel 1,000 cfm unit.

Test 1: 454 Stock Iron Block
  • Edelbrock Aluminum Heads: 2.18 intake valves, 1.88 exhaust valves, 110cc combustion chambers
  • Edelbrock RPM Camshaft: Hyd. flat-tappet
    Duration @ .050 Lift: Intake 240° Exhaust 246°
    Lobe Separation: 112°
    Lift at cam: Intake .330 Exhaust .337
    Intake Centerline: 107°
    Lift at valve: Intake .560 Exhaust .573
    Timing @ .050 lift: Open Close
    Intake 11° BTDC 49° ABDC
    Exhaust 57° BBDC 9° ATDC
  • Stock Stroke Crank
  • Intake: Edelbrock RPM Dual-Plane
  • Compression: 9.5:1
  • Rocker Ratio: 1.7
  • Header Diameter: 2 1/8 in.
  • Fuel: 92 Octane

Did I leave anything out? Too much information? Let me know so I can give you better stats in the future. Thanks again, Ron.

--Bullitt
 
S

sscam69

Guest
Sure no prob!

Those most important part is the camshaft that you are going to use. The more information the better. OH and the simulation performs better calculations from seat to seat timing on the camshaft.

This is what I need:
Bore:
Stroke:
Valve Sizes: Are they pocket ported/fully ported/race ported
Compression Ratio:
Whats the rated CFM on the carb:
Intake manifold: Single/dual plane/tunnel ram/turned port injected
Headers: yes or no w/muflers or w/o muflers

Camshaft:
Hydraulic/solid/roller
Lobe center angle (cam degrees)
Intake centerline (crank degrees)
Intake and exhuast duration

IVO (BTDC) / IVC(ABDC) intake valve open/intake valve close ***this refers to the number of degrees it takes for the intake valve to rise from the lowest to the highest and close respectively

EVO (BBDC) / EVC (ATDC) same but for the exhaust

Camshaft advance/retard:

As you can see the camshaft requires the most info. Edelbrock and Lunati have all the info posted on their cams. Comp Cams does not and the program just assumes and IVO/IVC...etc. This throws off the curve of the power/torque band. Thats why its important to get all the details.

When I crossed checked an edelbrock package with the simulation the curves were close. by about +/- 10-15hp and same for torque.

If the camshaft stuff just gets to confusing just let me know what cam (with id #) you want to use and I will look it up.

RON: what version do you have? I have 2.5.7M. Mine does not take into account boost. Sorry Bullit. Hey Ron I don't think it would hurt if we both ran the simulation, we could compare.

Frank
 
S

sscam69

Guest
Here you go

Ok Bullit the results are in!!

Only one problem the intake centerline did not match with the rest of the specs. All I have to input in the program are the IVO/IVC and the EVO/EVC and all the other specs show up.

As you can see the duration is correct 240/246 as indicated on your post. The lobe separation angle (LSA) was calculated to be 111.5, I just rounded to 112. It affected the EVO by 1 degree. The problem comes in with the intake centerline (ICL). After I plugged in the IVO.....etc the ICL was 109. If I corrected it to 107 the IVO would change by 2 degrees.

I checked both an ICL of 109/107 and the difference was 1HP/5ftlbs. The peak for both HP/TQ remained the same.

Frank
 
S

sscam69

Guest
Your going to love this one.

All I did was change the cam to a roller cam with the same specs and porting option with the heads.


Hope this helps. What were the numbers that were posted on the real thing?


Frank
 
B

Bullitt

Guest
Does this software measure the hp/torque at the crank or the rear wheels? If it's at the crank, I think I screwed up somwhere. Here's how the combo comes down from the sheet.

  • 2500 rpm: 209.2hp 452.5 torque
  • 3000rpm: 270.4 hp 473.4 torque
  • 3500rpm: 325.5hp 488.4 torque
  • 4000rpm: 371.7hp 490.0 torque
  • 4500rpm: 434.6hp 507.2 torque
  • 5000rpm: 484.6hp 509.1 torque
  • 5500rpm: 515.3hp 492.1 torque
  • 6000rpm: 523hp 457.8 torque
  • 6500rpm: 507.4hp 417.8 torque

As you can see, the numbers seem to fall between both simulated dyno runs. I'm going to go over the specs again and see what I missed. :(

--Bullitt
 
B

Bullitt

Guest
One thing is that the Edelbrock heads are ported, so I forgot to mention that. I'm assuming just pocket ported, though.
  • It would be headers with no mufflers, on this combo.
  • They didn't mention whether the cam was advanced or retarded, so I'm out on that one.
  • The intake valve should be 2.19. D'oh!
Let's see if that does it.

--Bullitt
 
S

sscam69

Guest
Ok Bullit the results are in!!

The did advance the cam by 2 degrees. That what was throwing off the intake centerline. If you look at the cam specs they are right on. I advanced the cam by 2 degrees and everything checked, thats how I figured that one out.

There is a lot of deviation on the torque end. Sometimes its close others its off by 30ftlbs. I am going to try an independent setup done by magazines just to make sure the numbers weren't "massaged". As for the HP it stays a little more consistant than the TQ.

I would think with a good ignition system and blueprinting everything and attention to detail like quench etc you could get more out of it.

Frank
 
S

sscam69

Guest
here are the specs

Let me know what else you want to try.

Frank
 
B

Bullitt

Guest
Yeah, with the right valve and the advance, it looked to bring it more in line. Thanks for figuring that one out. This combo reaches back around 6-7 years ago, I think. There's no telling what they left out of the article back then. I can't believe that I forgot what I read about advancing the camshaft. I must be losing brain cells or something. :crazy

The next thing that I want to try is the set-up run by the guys over at Crank&Chrome. I'll try to run down all the specs and see how close that one comes up on the simulation. The only thing would be comparing final ratings, because of the wheel dyno they used. I guess I can just use somewhere between 10-20% drivetrain loss as an equalizer.

After that I want to see how smaller valves, like the ones I got, affect hp and torque. This is important to me as it'll directly affect my wallet. I don't think I'll be able to spring for aluminum heads, but I'm willing to do some porting on the ones I got. Again, it all depends on what the $$$ figure will be.

I'll be concentrating on camshaft specs mostly from Lunati, because the information is on the web. When you said that you just needed a cam number, does that go for every cam for any manufacturer?

Anyways, I'll do that stuff later today. I'm taking a break from replacing rear rotors on a BMW right now. Man, those suckers were stuck on tight. Nothing that a sledgehammer and a pickle fork couldn't take care of, though. :L

--Bullitt
 
R

rpounds

Guest
Bullitt . . .

Looks like Frank got to you before I did!! Potent combo!!

Ron
 
S

sscam69

Guest
The manufacturer and the id they use for the camshaft, thats what I meant.

I know what you mean about those rotors!! Believe it or not the hardest brake job I have ever done up to know was on the rear brakes on my Vette!!! I had to replace the springs and stuff for the parking brake, talk about a PPPPIIIITTTTAAAA!!!

For a $30 program I think the results are good enough. I would not expect for a program like thise to be right on. Its virtually impossible to take everything into account of such a complex machine with so many complex processes going on.

I didn't have a chance to run those other combos, I think I am getting sick. I have a headache, body ache and my throat hurts. This sucks!!

Send over anything else, would be more than happy to run some sims.:)

Frank
 
B

Bullitt

Guest
Oh FUDGE!!!

I forgot that Crank&Chrome became Two Guys Garage, which entailed moving from TNN to SpeedVision...er... Speed Channel. That wouldn't be such a problem if they hadn't gotten rid of the previous website information. I don't remeber what type of 454 they were running. Looks like I'll have to go through my tapes. :(

--Bullitt
 
B

Bullitt

Guest
Crank&Chrome Combo

Okay, luckily it wasn't too hard to find. I hope you guys can try two different cam grinds, though.

  • 454 Motor with stock bore&stroke.
  • Heads: Aluminum Holley with 119cc combustion chambers
  • Valves: Intake-2.25 Exhaust-1.88
  • Compression: 8.5:1
  • Carburetor: 770cfm
  • Camshaft: Lunati
    Advertised Duration: 293° intake/ 310° exhaust
    Duration @ .050: 232° intake/ 239° exhaust
    Lift @ Valve: .549" intake/ .558" exhaust
    Lift @ Lobe: .323" intake/ .328" exhaust
    Lobe Seperation: 110°
    Intake Centerline: 104°
    Open/Closes @ .050: 12°BTC 40°ABC / 55.5°BBC 03.5°ATC

This camshaft I think is a step down.
  • Camshaft: Lunati
  • Advertised Duration: 292° intake/ 292° exhaust
  • Duration @ .050: 230° intake/ 230° exhaust
  • Lift @ Valve: .544" intake/ .544" exhaust
  • Lift @ Lobe: 320" intake/ .320" exhaust
  • Lobe seperation: 109°
  • Intake Centerline: 107°
  • Open/Close @ .050: 08°BTC 42°ABC / 46°BBC 04°ATC
Could you try both camshafts with everything else being equal and see what we get? One more thing Frank. If you have the Comp Cams catalog, can you try to see if they have similar grinds close to the ones I just posted? Thanks again.

--Bullitt
 
B

Bullitt

Guest
Oops!

Forgot a few things. The heads are ported. The exhaust set-up will be with headers and through mufflers. The camshaft with 2 degrees of advance. :upthumbs

--Bullitt
 

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