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SBC 350 cam comparison, - dyno software run please ?

10K views 18 replies 4 participants last post by  Ocean-Angler 
#1 ·
Thanks again for all the help Ive gotten here. But its time to build this motor with some balls. Ive got all the parts figured except wanted to have someone who has one of those dyno softwares to run some cams for me and see what the software things will work better
I know its not a complete real world number, but atleast itll show me my torque/horsepower curve so I can choose better..

Heres what Ive got
350 - not bored, not stroked ( will get to the bottom end when I have the space and time)
750 carb mech. secondary
edelbrocker air gap performer intake
AFR 195CC heads 64 CC chambers ..... 2.05 / 1.06
9.5:1 CR ( again, will get to that when I get to the bottom end and bump prob. to 10.7ish :1)
ignition box
2800stall, 700r4, 3.55 gear ( 26" tall tires.. so similar to 3.73 with most guys tires)
car weight 3700 lbs


ok cam specs -
240/245 duration @ .50
.570/.585 lift
106LSA

now run with same cam, but 108LSA

then
234/246 duration @ .50
.530/.550 lift LSA 110

now run with same cam, but 106LSA

then with

230/238 duration @ .50
.528/.548 lift
108LSA


if anyone would be willing to do this, I would greatly appreciate it.
Ill even send $8 paypal LOL
sorry this engine is sorta gonna break me, so I wanna be able to compare the potential here and make the right choice
thanks guys
 
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#3 ·
I have Dynomation 5 software and will run these for you but it wants to know about exhaust and would be MUCH better with more cam info. If you could give part numbers on cams it would be much more accurate and easier to do since the cam files are listed by manufacturer and part number-NOT grind numbers.
Ignition is not considered except that it is set up and sufficient.
If you have a cam in mind, I can adjust for LSA easily.
No charge :D
 
#4 ·
Hotrodrobert said:
I have Dynomation 5 software and will run these for you but it wants to know about exhaust and would be MUCH better with more cam info. If you could give part numbers on cams it would be much more accurate and easier to do since the cam files are listed by manufacturer and part number-NOT grind numbers.
Ignition is not considered except that it is set up and sufficient.
If you have a cam in mind, I can adjust for LSA easily.
No charge :D
Hell yea man!!
cool thanks
let me see
exhaust - 3/4 length headers ( 1 5/8") x over pipe, I think 2.5" dual with flowmasters. Not sure which though

hmm cam specifics..
lets see
Crane Cams - 119571
Advertised Duration - 292/300
230/238 duration @ .50
.528/.548 lift
108LSA

I cant find the specs on the ISKY, or the Herbert cam... so I guess if the above stats for the crane is enough we can try that one with 108, then with 106 LSA

Ill call ISKY and Herbert tomorrow to get the specifics of the others
thanks alot man, hoping the additional stats will help get a dyno from you

if possible, maybe we can even tweek some numbers, like changing the duration a little as suggested and make it more of a single pattern..
I guess before I go any further with asking for anymore tweeks, let me know if the existing numbers work or you need more
thanks again man
 
#5 ·
I need to know what you are going to do with this engine-drag, road race, street, street/strip??
Those LSAs are usually race numbers and street numbers usually start at 108 like Isky likes and go to 114 for mild street. Low numbers narrow the power band and the really low ones like 106 or lower are really not nice on the street.
I have a function that will design a cam for you that is pretty good but not exact-just a starting point.
Comp Cams also has their FREE Camquest program. Just go to their website and download. It only lets you choose from their catalogue and Dynomation gives you custom numbers and you have to find a grinder that has one or can make it for you. Comp will grind anything you want quickly at the same price as shelf cams, Isky has Ron Iskenderian who can tell you just what you need, too.
 
#6 · (Edited)
Hotrodrobert, this should give you all the info you need to run a sim....use 10.25 for static compression ratio and install an RPM intake (max flow dual-plane), 750 carb and 1 3/4" long tube headers....

Crane part number 119571
Crane grind number HR230/352-2S1-8 IG Hydraulic Roller camshaft
Retrofits Gen I block 1957-1987 262-400

Intake
Opens 12 BTDC @0.050" tappet lift
Closes 38 ABDC @0.050" tappet lift
Duration @0.050" tappet lift, 230
Opens 39 BTDC @0.004" tappet lift
Closes 73 ABDC @0.004" tappet lift
Duration @0.004" tappet lift, 292
Lobe center 103 ATDC
Lift w/1.5 rocker, 0.528"

Exhaust
Opens 52 BBDC @0.050" tappet lift
Closes 6 ATDC @0.050" tappet lift
Duration @ 0.050" tappet lift, 238
Opens 79 BBDC @0.004" tappet lift
Closes 41 ATDC @ 0.004" tappet lift
Duration @ 0.004" tappet lift 300
Lobe center 113 BTDC
Lift w/1.5 rocker, 0.548"

Lobe separation angle 108 degrees

Minimum rpm's 2400
Maximum rpm's 6400
Valve float 7000

Good mid range torque and HP, fair idle, moderate performance usage, serious off road, mild bracket racing w/ heavy car, auto trans w/2500+ converter, 3000- 3800 cruise RPM, 9.5 to 10.75 compression ratio advised.

Weingartner flowed a set of AFR195's and I'd trust their numbers....
0.100" 73/53
0.200" 146/108
0.300" 210/150
0.400" 258/176
0.500" 279/186
0.600" 273/191
0.700" 275/192
 
#7 · (Edited)
This 30 minute limit on edits makes me nuts. I'll repost the post here with changes. Disregard the previous post (#6)....

Hotrodrobert, this should give you all the info you need to run a sim....use 9.835:1 for static compression ratio and install an RPM intake (max flow dual-plane), 750 carb and 1 3/4" long tube headers....

Crane part number 119571
Crane grind number HR230/352-2S1-8 IG Hydraulic Roller camshaft
Retrofits Gen I block 1957-1987 262-400

Intake
Opens 12 BTDC @0.050" tappet lift
Closes 38 ABDC @0.050" tappet lift
Duration @0.050" tappet lift, 230
Opens 39 BTDC @0.004" tappet lift
Closes 73 ABDC @0.004" tappet lift
Duration @0.004" tappet lift, 292
Lobe center 103 ATDC
Lift w/1.5 rocker, 0.528"

Exhaust
Opens 52 BBDC @0.050" tappet lift
Closes 6 ATDC @0.050" tappet lift
Duration @ 0.050" tappet lift, 238
Opens 79 BBDC @0.004" tappet lift
Closes 41 ATDC @ 0.004" tappet lift
Duration @ 0.004" tappet lift 300
Lobe center 113 BTDC
Lift w/1.5 rocker, 0.548"

Lobe separation angle 108 degrees

Minimum rpm's 2400
Maximum rpm's 6400
Valve float 7000

Good mid range torque and HP, fair idle, moderate performance usage, serious off road, mild bracket racing w/ heavy car, auto trans w/2500+ converter, 3000- 3800 cruise RPM, 9.5 to 10.75 compression ratio advised.

Weingartner flowed a set of AFR195's and I'd trust their numbers....
0.100" 73/53
0.200" 146/108
0.300" 210/150
0.400" 258/176
0.500" 279/186
0.600" 273/191
0.700" 275/192

OceanAngler, set squish at 0.035"-0.045". Use this piston or one exactly like it to reach a 9.835:1 SCR. Have AFR cut the heads for 62 cc chamber volume. A DCR of 8.0:1 to 8.75:1 will work well with pump gas.
http://www.kb-silvolite.com/kb_car/performance.php?action=comp
With 62cc heads, SCR will be 9.835 and DCR will be 8.513:1.

Begin your build properly with align-honing or align-boring the main bearing bore, then cut the block decks off the centerline of the mains to insure that the heads will be exactly the same distance from the centerline of the crank on both ends of the heads. This will go a long way toward sealing up the intake manifold so that you have no oily vapor sucked into the intake port with the intake valve open. With chambers that are close, it will also insure that the SCR will be the same on all cylinders. Build it properly or take up another hobby.
 
#8 ·
hey technispector, thanks for givin him the specs on that crane
Herbert -
This is going to be a street/ocassional strip car
mainly I wanna be racing this thing on the street

I used the camquest program from comp cams, which was cool, but then when I called comp cams, they gave me cam recomnedations that were different, given the same parameters that I gave them

I also called ISKY too, and got a cam recomendation from them, but dont have all the details from that cam to give you to have you run the specs

basically with the logic behind the 106LSA, I got from Herbert cams -
I wanted a slightly higher duration the I initially got from Comp cams, ( went from 230ish - 240ish instead) to pick up a little more HP, and slightly higher lift as well to grab a little more horsepower

But I went down to a 106/108 LSA instead to drop my powerband back down since the higher duration brought it up.
That way I could bring it down towards the 2500/2800 RPM - 6500/6800 RPM as opposed to 3000-7000 that a normal cam with the 240 duration .570 lift would operate
I talked to 2 techs at Lunati; the first one gave me the cam profile, then trnsferred me to the second one, the engineer. I asked him about keeping the same profile, but changing the LSA from 110- 108/106 HE explained what Ive been seeing online - the lower LSA brings down the operating range, narrows it a little, and peaks it a little more. which is exactly what Id want when the profile on the cam is going to make the powerband aat a higher rpm then I want...
However, and maybe this is what youre refering to, I dont know how that would idl with an LSA that low.. im guessing really rough maybe? maybe if u have more insight as to what makes an LSA like that not very streetable that would be great if u culd tell me

ALso, as of now, the compression is only going to be around 9.5ish
keep me up to date
thanks again
 
#10 ·
techinspector1 said:
This 30 minute limit on edits makes me nuts. I'll repost the post here with changes. Disregard the previous post (#6)....

Hotrodrobert, this should give you all the info you need to run a sim....use 9.835:1 for static compression ratio and install an RPM intake (max flow dual-plane), 750 carb and 1 3/4" long tube headers....

Crane part number 119571
Crane grind number HR230/352-2S1-8 IG Hydraulic Roller camshaft
Retrofits Gen I block 1957-1987 262-400

Intake
Opens 12 BTDC @0.050" tappet lift
Closes 38 ABDC @0.050" tappet lift
Duration @0.050" tappet lift, 230
Opens 39 BTDC @0.004" tappet lift
Closes 73 ABDC @0.004" tappet lift
Duration @0.004" tappet lift, 292
Lobe center 103 ATDC
Lift w/1.5 rocker, 0.528"

Exhaust
Opens 52 BBDC @0.050" tappet lift
Closes 6 ATDC @0.050" tappet lift
Duration @ 0.050" tappet lift, 238
Opens 79 BBDC @0.004" tappet lift
Closes 41 ATDC @ 0.004" tappet lift
Duration @ 0.004" tappet lift 300
Lobe center 113 BTDC
Lift w/1.5 rocker, 0.548"

Lobe separation angle 108 degrees

Minimum rpm's 2400
Maximum rpm's 6400
Valve float 7000

Good mid range torque and HP, fair idle, moderate performance usage, serious off road, mild bracket racing w/ heavy car, auto trans w/2500+ converter, 3000- 3800 cruise RPM, 9.5 to 10.75 compression ratio advised.

Weingartner flowed a set of AFR195's and I'd trust their numbers....
0.100" 73/53
0.200" 146/108
0.300" 210/150
0.400" 258/176
0.500" 279/186
0.600" 273/191
0.700" 275/192

OceanAngler, set squish at 0.035"-0.045". Use this piston or one exactly like it to reach a 9.835:1 SCR. Have AFR cut the heads for 62 cc chamber volume. A DCR of 8.0:1 to 8.75:1 will work well with pump gas.
http://www.kb-silvolite.com/kb_car/performance.php?action=comp
With 62cc heads, SCR will be 9.835 and DCR will be 8.513:1.

Begin your build properly with align-honing or align-boring the main bearing bore, then cut the block decks off the centerline of the mains to insure that the heads will be exactly the same distance from the centerline of the crank on both ends of the heads. This will go a long way toward sealing up the intake manifold so that you have no oily vapor sucked into the intake port with the intake valve open. With chambers that are close, it will also insure that the SCR will be the same on all cylinders. Build it properly or take up another hobby.
thanks for the tips and piston recomendations.
I was going to do the top end first, and then when I got a little more time and space freed up, take the block out, and bring it to the machinist and balancer ive used before and have him to the machining... I know I should do that first, but I just cant get to the bottom end yet. I dont have a place to pull out the block with an engine stand and cherry picker, we live in a gay *** uptight nazhi community where neighbors complain all the time
 
#12 ·
Hotrodrobert said:
From the data you gave me but advancing the cam 4 deg., the torque is much better, the HP better to 6500:
Hey Robert, thanks alot
this is the data from which cam? the one I sent the extra details on..?
and advancing the cam 4 degrees, is that the same as when i simply advance the distributor?
and what was the compression ratio you put in on that?
thanks again Rob
 
#13 ·
That was the cam info you sent. I used 9.4CR because my program only allows one decimal point.
If you don't know what advancing the cam means, you can't do it alone without a LOT of study. Advancing the cam is done with the timing gears and requires tools the average person doesn't have. You can get timing sets that have extra key slots in the crank gear, but the system isn't always just right.
Also, my program has an Iterator function that will design a better cam for the info on the engine and it says you need a smaller cam for best performance up to 6500RPM. It recommends about 270 intake and 280 exhaust on 110 LSA. Look at an Isky 201272282. It is close. Or 201275284. Others companies have similar and in the under 6500 range will beat the cam you gave me the specs for by a lot in your engine. After 6500 is meaningless when the other guy is so far ahead you will never catch him!!!!!!!!!!!
 
#16 ·
Hotrodrobert said:
That was the cam info you sent. I used 9.4CR because my program only allows one decimal point.
If you don't know what advancing the cam means, you can't do it alone without a LOT of study. Advancing the cam is done with the timing gears and requires tools the average person doesn't have. You can get timing sets that have extra key slots in the crank gear, but the system isn't always just right.
Also, my program has an Iterator function that will design a better cam for the info on the engine and it says you need a smaller cam for best performance up to 6500RPM. It recommends about 270 intake and 280 exhaust on 110 LSA. Look at an Isky 201272282. It is close. Or 201275284. Others companies have similar and in the under 6500 range will beat the cam you gave me the specs for by a lot in your engine. After 6500 is meaningless when the other guy is so far ahead you will never catch him!!!!!!!!!!!
Hey man, thanks alot I really appreciate it.
the 270/280 durations that you suggested; ISKY, those are advertised durations right, not @ .50 durations.?
 
#17 ·
Hotrodrobert said:
I don't know yet how to post the program results directly to the board.
Also, I did the Iterator function on your engine and also the Comp Cams program. Both gave much better power from 0 to 6000 and almost as much HP to 6500 with smaller cams.
oh cool man!!

yea, I guess Id rather go with what the program shows, then the cam that I kinda had my eyes set on.. although the numbers might not be exact, the general idea the program establishes, should be accurate..
Recently I read that the exhaust pipe and diameter length does slightly affect the proper cam tuning. . I dont think your program goes into that detail though

I really REALLY wanted to go with the Herbert Cam; @ 50 - 240/245, Lift .570/.580 LSA 106.. But if we can run that deal you were talkin about, and it shows a better band, then thats the best idea

I was tryin to basically have the bulk peak the torque around 2600 - 5000
with an actual peak maybe at 6000 or slightly above, and peak hp above it..
so Id shift at .. 6200-6800ish, and keep my RPMS between 3000 and above mainataining that peak.
For sure though give me a call and we could run some numbers and see what it shows

Byron

thanks man
 
#18 ·
The 270-280 is advertised.
The Herbert cam is way too big for your combo but they have some not too far off.
A good cam for your combo should be in the high 220s to low 230s at .050" on the intake and 6-10 degrees more on the exhaust.
My program has a function that considers the header tube size, length, step or not, collector diameter and length, total exhaust length and more but to use it you must have measurements from the heads and intake that are hard to get and no one I know lists those. If you use all of them, it seems to be pretty close to right but the "emptying and filling" does OK and does give pretty good comparative information. If it says it won't work, usually (but not always) it won't. Some combos run much better than the program predicts, some much worse.
Just a tool and fun to play with.
 
#19 · (Edited)
Hotrodrobert said:
The 270-280 is advertised.
The Herbert cam is way too big for your combo but they have some not too far off.
A good cam for your combo should be in the high 220s to low 230s at .050" on the intake and 6-10 degrees more on the exhaust.
My program has a function that considers the header tube size, length, step or not, collector diameter and length, total exhaust length and more but to use it you must have measurements from the heads and intake that are hard to get and no one I know lists those. If you use all of them, it seems to be pretty close to right but the "emptying and filling" does OK and does give pretty good comparative information. If it says it won't work, usually (but not always) it won't. Some combos run much better than the program predicts, some much worse.
Just a tool and fun to play with.
So I checked on some exhaust stuff, dont know how much it helps but

roughly 150" of exhaust length from the end of the collectors to the end of the tailpipes.
2 flowmasters, outlet size at the tailpipes is 2.25"
the tubes on the headers vary in length, average size is 18" length, and the collectors roughly 5" length
Dont know if that helps
oh, if my exhaust pipes are going to be constricting my poptential horsepower or torque below 7,000, then theyll get changed..


thanks again
 
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