Anybody have software to run a cam for me? I got some very nice results on Dyno 2000 but would like some support from another run. Cam is: Hydraulic Roller, LSA 107, advertised duration 283in/303ex, duration @ .050" 235in/249ex, valve lift .521in/.507ex. Using a 327/365 1965 motor with stock 2 1/2" exhaust, stock HP dual plain intake, stock Holley 4 bbl., pocket ported 2.02/1.60 stock heads.

 

I had to make a few guesses on the cam, carb and exhaust but this is what my computer says....

Analysis Report for Street/Strip Engine with Desired HP Peak at 6000 RPM

Peak Tq =312. @ 4500 RPM .95 Ft Lbs per CuIn
Peak HP =304. @ 5500 RPM .93 HP per CuIn

Maximum Exhaust System Backpressure 'Exh Pres' is 3.6 PSI.
This is somewhat high for a street/strip engine and will limit Tq
& HP. To simulate open headers, select the 'Open Headers' from the
Exh System Type combo box.

Typical ranges of Exhaust System Backpressure are listed on page
32 in the User's Manual. You can lower the Back pressure by
increasing Exh System CFM Rating in the Exhaust Specs menu.
Lowering the Exh System CFM Rating will simulate a quieter, more
restrictive exhaust system. Most dyno tests are done with open
headers, which are simulated by selecting the 'Open Headers' from
the Exh System Type combo box.


Maximum Intake Manifold Vacuum 'Int Vacuum' is 1.1 ''Hg.
This is somewhat high and is limiting air flow and HP.

Reduce Int Vacuum by specifying a larger Carb-T/B CFM Rating in the
Intake Specs menu. Some classes of racing limit performance by
specifying a small Carb or a restrictor plate. In these cases,
you must try to improve performance with this small Carb CFM Rating
or legally make small improvements in the Carb CFM Rating.


Maximum Volumetric Efficiency 'VE %' is 85.7 %.
This is somewhat low for a 'non-supercharged' street/strip engine.
Typical 'non-supercharged' street/strip engines have VEs of 85-105%.

Volumetric efficiency is the best measure of an engine's air flow
capability at a particular RPM. High VE is is critical to obtain
high torque and HP. See page 73 for a definition of volumetric
efficiency. Most all engine specs affect VE and the RPM at which
peak VE occurs. Generally, engine torque will peak close to the
RPM giving peak VE.


Maximum Fuel Flow 'Fuel Flow' is 191 lbs/hr GAS.
This is equal to 32.7 gallons per hour of fuel flow.
For an injected engine with one injector per cylinder, you will require
at least 24 lbs/hr injectors.

Fuel Flow will only change if air flow changes or if you inject
nitrous. The Engine Analyzer assumes 12.5:1 A/F for gasoline and
5:1 for alcohol (methanol) and 3:1 for 'Very Rich Alcohol' for all
conditions. You can not richen or lean out the fuel mixture.


Mechanical Efficiency 'Mech Eff' is 73 %
at the current Peak HP RPM of 5500 RPM.
This is somewhat low and represents a real power loss in this
engine's current operating range. This can be improved by paying
close attention to details in the Short Block Specs menu.

Mechanical Efficiency can be improved by:
- Better matching the Supercharger size or Belt Ratio to
the engine if the engine is Supercharged
- Reducing piston skirt size or piston ring tension
- Minimizing 'power robbing' accessories
- Reducing crankcase windage
- Reducing stroke
- Reducing valve spring loads
- Reducing the engine's operating RPM range


Your 'Desired HP Peak RPM' you entered for the Analysis Report
matches the 'For Peak HP at this RPM' spec you entered in the lower
right corner of the Running Conditions menu (the menu containing
the Weather Conditions, RPMS to Run, etc.)

Check the 'Approx Cam for HP Peak' suggestions at the bottom of
the Special Calculations section of the calculated test results.
They will suggest APPROXIMATE cam specs to produce a HP peak at
this RPM with your current cylinder heads. (If you don't see the
Special Calculations section, click on View, then click on 'Show
Special Calculations'. Then click and drag the scroll bar button
on the right side of this section down to see all the Special
Calculations, including these suggestions.)


The Maximum Average Piston Speed 'Piston Spd' is 3524 ft/min
at the Performance Calculations Maximum RPM of 6500 RPM.
This is Very high (if you want to run this entire speed range),
requiring light, high strength reciprocating components.

A street/strip engine should limit Piston Spd to a range of 3000-4000
ft/min. However, even to run at 3000 ft/min or higher, you will need
'better than production', high quality reciprocating components
(connecting rods & bolts, pistons, etc.).

Piston Spd (average piston speed in ft/min) and Piston Gs (peak
piston Gs) are indicators of how severely you are stressing the
engine's rotating components. To lower Piston Spd and Piston Gs,
you must shorten the piston Stroke or design the engine for a lower
RPM range.

Maintaining low Piston Spd and Piston Gs are critical for 'keeping the
engine together'. OVER-REVVING PARTS BEYOND THEIR INTENDED LIMIT IS
UNSAFE FOR THE ENGINE, YOURSELF AND BYSTANDERS.


Maximum Contribution to VE During Overlap 'Overlap %VE' is 0 %.
This is Very low for street/strip engines which typically show
3-8%. Low Overlap %VE will limit Tq & HP and is most likely is caused
by high exhaust backpressure, high intake vacuum, exceptionally poor
intake and/or exhaust tuning or too little valve overlap.

It is normal for Overlap %VE to dip (even go negative) at some RPMS.
You will not be able to eliminate these dips and still maintain high
Overlap %VE at other RPMs. However, you may be able to move the dips
outside your desired RPM band.

Overlap %VE is the amount that volumetric efficiency (and performance)
improves by tuning or is hurt by intake reversion during overlap.
Overlap %VE improves (is a high positive + number) when:

- Exhaust pressure 'Exh Pres' is low
- Exhaust tuning pressure during overlap 'ExTun Prs' is low
(a large negative number).
- Intake vacuum 'Int Vacuum' is low
- Intake tuning pressure during overlap 'In ResTunPrs' is high

The tuning pressures are affected by runner dimensions and somewhat
by cam timing. Review Appendix 5 on intake and exhaust tuning.

Overlap %VE is also strongly affected by the amount of cam overlap. If
the pressures mentioned above are good and the cam has a large
overlap, OV %VE will be high and help performance. If these pres-
sures are good, but cam overlap is low, Overlap %VE will be less
and the performance improvement will be less.


The Intake Runner Velocity 'Int AvgVel' is 318 ft/sec
at your 'Desired HP Peak RPM' 6000 RPM.
This is somewhat high and indicates you will need a larger Intake
Runner Diameter or larger Intake Port Diameter for less
restriction and stronger intake tuning.

For these engine specs, an 'Int AvgVel' of about 260 should work well.
If the 'Int AvgVel' is approximately 30-80 Ft/Sec higher than this,
you will likely improve torque below this RPM, but lose some HP.


The Inertia tuning of this intake is tuned to 5544 RPM,
which is close to your 'Desired HP Peak RPM' of 6000 RPM.
Since this RPM is about where the HP peak should occur, peak HP
should be good. If you specify longer and/or smaller diameter intake
runners, you will likely gain Peak Torque and lose some Peak HP.


Your 'Desired HP Peak RPM' you entered for the Analysis Report
matches the 'For Peak HP at this RPM' spec you entered in the lower
right corner of the Running Conditions menu (the menu containing
the Weather Conditions, RPMS to Run, etc.)

Check the 'Intake Port+Runner Dimensions' suggestions in the Special
Calculations section at the bottom of the calculated results. They
will suggest APPROXIMATE dimensions for Intake Runner Length
and Runner Diameters you can try to produce strong intake inertia
tuning at your Desired HP Peak RPM. (If you don't see the Special
Calculations section, click on View, then click on 'Show Special
Calculations'. Then click and drag the scroll bar button down on
the right side of this section to see all the Special Calculations,
including these suggestions.)

IMPORTANT: These runner dimensions are for the entire runner from
the valve to the plenum, which includes the port in the head and
runner in the manifold. Be sure to divide these suggested lengths
between the port AND runner. For example, if the suggested Intake
Length is 15, and 5 inches is in the port, use 10 inches in the
manifold runner.

IMPORTANT: These runner dimensions are based on the CURRENT engine's
CAM SPECS. If you change cam specs (for example to the cam suggested
in this section), these runner specs will also change. Therefore,
if you are following these suggestions, put in the suggested cam specs
first, recalculate performance, then put in one of the sets of
intake runner dimensions suggested with the new cam specs.


Intake and/or Exhaust 'Valve Toss' is indicated at 1 RPM(s).
Valve Toss is the condition where there is insufficient valve spring
pressure to keep the lifter in contact with the cam. Valve Toss
causes severe stress and damage in the valve train and must be avoided.

Valve Toss can be avoided by reducing valve train weight,
going to gentler cam profiles (less lift for the same or less
duration), stiffer valve train components, or reducing the
engine's operating RPM range.



At 2 different RPMs, Spark Advance 'Spark Adv' is retarded to avoid
detonation. Retarding Spark Adv does reduce performance, but allows this
engine to safely operate with this Octane fuel.

You can reduce the likelihood of detonation, by increasing Fuel
Octane or Dew Point (humidity), or reducing Intake Air Temp or
Cooland Temp in the Running Conditions menu, or reducing
Compression Ratio in the Head(s) Specs menu. Also, anything
which reduces performance, or shifts the performance curve to a
higher RPM range will also reduce the likelihood of detonation. By
reducing the likelihood of detonation, you avoid the necessity of
retarding Spark Adv.

Retarding Spark Adv from what the engine actually wants is not
necessarily a 'bad thing'. The best performance for a particular
RPM range and Fuel Octane may come with spark retarded from optimum.
Just be sure to retard spark in the actual engine to avoid detonation
which will cause engine damage.

Also, retarding spark increases exhaust temperatures, which can
damage exhaust valves, turbo turbines, etc.


IMPORTANT: The Optimize feature at the top of the Main Screen is
an excellent way to find combinations which work well together.
Click on 'Help' in the Optimize screen for tips on this feature.

End of Analysis Report


I ran it again with open exhaust:


Peak Tq =332. @ 4500 RPM 1.02 Ft Lbs per CuIn
Peak HP =331. @ 5500 RPM 1.01 HP per CuIn

 

IMHO, I would find a cam with a LSA of 112 or even 114 to go with the stock exhaust, if not the resultant overlap will kill your bottom end.

 

Geeeezzz,

I ran it with my Dyno 2000 and hp was 398 at 6,000 and tq 387 at 4,500. Big difference in software? This is a hydraulic roller cam. Is made for this type motor per the manufacturer. Very interesting. Any other dynos out there that can try a run?

 

Man do I agree. Spread the centerlines. When you're running manifolds it's useful to open the exhuast valve pretty early to use higher cylinder pressure to help clear the cylinder. This is one of the reasons Chevy made (and continues to do this on the LS series) all those broad LC cams with significantly longer exhaust timing. BTW to compare solid cams to hydraulics (I've measured a quite a few) add 12 degrees of duration.

 

With a pocket port and a gasket match w/the intake Im guessing your
heads are flowing 210cfm @ .400, .500..... but you are restricted with
your stock manifold,carb, and exhaust manifold..

I think 398 is possible with those heads and cam with optimum aftermarket carb, int, and exhaust... but I don't think you'd be there with your current set up..

 

I concur with the wider lobe sep. I have a 110 in my set up and my dyno app pretty much agrees with my real dyno runs. But the software is only as good as the data you put in and as I said I made a few guesses on yours but have the exact detail on mine. I think the 398 seems a bit high especially with an exhaust. Of note on mine with a 110 sep I loose a lot of power with an exhaust. I have to go to extreme effort with the exhaust system or go to a wider sep to keep the power up.

 

Could this be one of those Thumpr Cams from Comp Cams?
I've been checking that out myself.

 

Yep, it is and they claim the cam is made specifically for a motor like mine without mods. Just stock hi performance 327/365 with 2 1/2 exhaust. It works just like they said on my Dyno 2000 but I wanted to see what others say and think.

 

Personally if it says "Comp Cams" on it I stay away, too many cams with excess base circle runout from that outfit! How may of you guys ever take the time to check that, it's more than likely a big contributor with their cams going flat.

 

Oh Great, I just got talked into switching to CompCams.....Personally I always like my UltraDyne cams but they were bought out since the last time I ordered from them, and even if some of the people are the same and the service seemed maybe a bit better, my engine builder is a Comp guy and really felt better going with them.....oh well if I don't like it or it goes flat I will know better next time.

 

Well the Ultradyne crew all went to Lunati at least Harold and Steve did.

 

Ok, I ran Dyno 2000 for an LT-1 cam and the 30-30. On a stock 327/365 motor.

The LT-1 was 368hp @ 6000rpm and 349tq @ 4500rpm. Also tq @ 2000rpm was 281.

The 30-30 was 352hp @ 6500rpm and 323tq @ 5000rpm. Also tq @ 2000rpm was 243.

Can someone double check this on a different dyno software program? Also, what if any difference is the cam sound regarding the lopy, rumpity/rump ?

 

Ken,
I replied on this in your other thread, but with Manifolds... you want at least 112 if not 114 LSA.. with that much duration.

that 107 is gonna be terrible...

new cam manufactures do not understand this, even if they say it will work with manifolds, they do ZERO testing to prove it.

I went from the 30-30 cam to a small Lunati (Ultradyne) cam which had 20 less degrees of duratin at .050 and about 40 degrees less at the seat with more lift , on a 111LSA. ( it was a full race, circle track cam, designed for a restricted manifold class).... the 30-30 blows its doors off from Idle to 6500rpm... I was very disapointed...

i'm sure with headers, that it woldhave been a different story.

Thanks

A

 

Harold is done at Lunati...

he is doing his own stuff.. but you can still order the old Ultradyne grinds from Bullet cams, and Lunati has the newer Ultradyne and the latest grinded designed by harold.

A

 

Roller cams do not go-flat.. no worries!

 

I don't have any dyno software results, for what it's worth, I ran a hydraulic flat tappet cam in a '68 Camaro for several years with a 105* LSA. It was a 10:1 350, with ported 2.02 valve 461 heads, 1 3/4 " headers, 650 D.P. Holley,3.55 gears, Muncie 4 speed M20.The cam had similar duration numbers to the cam that you are looking at. The car was driven daily. The car had gobs of torque, and would fry the tires off in the first two gears. Expect a rough, racy idle.The gas mileage was terrible, but I didn't care. It really was a lot of fun to drive.Iwouldn't hesitate to run a cam with a 107* LSA in a weekend toy.
Cheers,
Bill

 

I don't care about gas mileage. Just looking for a bad a-- sounding cam and good manners. Probably will go with the 30-30 or LT-1 since that seems to be the majority rules on the forum and since I am not cam savvy, I gotta go with what everyone says. But I love the lopy/ rumpity rump of a radical cam.

 

you had headers... so you can't compare that to a motor with manifolds..

tight LSA and cast manifolds will be a huge problem..
Duke preached on this. and i agree (from real world experiance)

its not about the manners of a 105 or 108 LSA,

my 64 coupe had an ISKY solid roller on 107 lsa with 242-252 duration and 570 lift... car sounded bad ***... but the manifolds killed it.

runs much better with the 30-30... and all i did was swap the cam, lifters, changed the springs, and went back to non roller rockers. nothing else.

A

 

Aaron, you are probably correct. I was only sharing my personal observations, and viewpoint.

On another note, I also own, and race the Nova shown in these photos. The car runs high 9's with an injected 383 on methanol. The cam in it is an Engle mechanical roller, .678" lift, 277* @ .050" duration,108* LSA. The Engle technician that recommended it stated that it would work better, and was designed for, open exhaust. My latest testing has found that I have gotten quicker E.T.s as well as faster trap speeds with running mufflers. My personal philosophy is to take advice for what it is, test, and then accept, or reject it.
Cheers,
Bill