just want some reassurance on combo choices

Grumpy

Thread 'push rods rub??'

First post here, but been reading a while so hang with me:

Hello all i am new to the v8 scene i have a new to me 1970 nova with an unknown 350 in it. It has 041 heads and for the most part seems very stock. The engine seems very low miles but has defiantly sat for a long time, as when i first got the car the valve covers were full of milkshake sludge but there is no coolant leak, just to give an idea of the condition...

I was in the process of finishing a tune when it developed a valve tick, i pulled the cover to find that the number 2 intake rocker had rotated off the valve. I found...
Click to expand...

grumpyvette

Thread 'valve train clearances and problems'

you might want to read thru these links and sub links it will help you avoid costly mistakes

valve_failure.jpg

http://www.summitracing.com/parts/pro-66830/overview/
pro-66830_cp.jpg

liftc1f.jpg
...

chromebumpers

Thread 'Valve Springs'

I met another neighbor yesterday. We started on cars and what he has in his barn, so he invited me over to give an opinion. He has a 1968 Nova with a 350 auto in great condition. I had to bite my lip to avoid asking if he would sell it. 1968s had the nicest dashboard and gauge setup of all the years. He’s interested in giving this car to his grandson (16) - after he finishes the help he promised to do around the house this summer. This grandson loves to clean the car when he comes to visit. Grandpa provides plenty of Pledge spray furniture Polish and a pile of old cotton clothes as...
  • Like

grumpyvette

Thread 'valve springs loads and installed height'

AmericanPie said:
Soon I'll be doing a mostly stock rebuild of the original 327/300 from my '65 Impala, using a mild (216/228 @ .050" dur., .454"/.480" lift) hydraulic Crane cam. I've been advised that Crane springs tend to be too strong for street use and will probably wear the cam prematurely. Is this true, and if so what would be a good choice in quality springs for this engine? This will be basically a street cruiser, w/ power peak of about 5500 rpm. Thanks!
Click to expand...

ASSUMING ALL VALVE SPRINGS FROM ANY SOURCE are too strong, too weak or anything else is absurd ! keep in mind the LAST THING any...

grumpyvette

Thread 'shaft rockers vs rocker stud girdles'

always call the cylinder head manufacturer for their input on rocker stud girdles,BEFORE PURCHASING THEM< because rocker stud spacing, and stud angles can vary, between head designs and models

READ THRU THIS THREAD ALSO

its not horsepower, its the stress on the valve train, that makes a rocker stud girdle and its increased rigidity useful,
and thats more closely related to average stress levels, RPM and VALVE SPRING LOAD RATES
any time your occasionally exceeding 6000rpm or getting close too 330 lbs of open valve load rate Id strongly suggest screw in rocker studs
any...
 
Grumpy said:
Grumpy

Thread 'push rods rub??'

First post here, but been reading a while so hang with me:

Hello all i am new to the v8 scene i have a new to me 1970 nova with an unknown 350 in it. It has 041 heads and for the most part seems very stock. The engine seems very low miles but has defiantly sat for a long time, as when i first got the car the valve covers were full of milkshake sludge but there is no coolant leak, just to give an idea of the condition...

I was in the process of finishing a tune when it developed a valve tick, i pulled the cover to find that the number 2 intake rocker had rotated off the valve. I found...
Click to expand...

grumpyvette

Thread 'valve train clearances and problems'

you might want to read thru these links and sub links it will help you avoid costly mistakes

valve_failure.jpg

http://www.summitracing.com/parts/pro-66830/overview/
pro-66830_cp.jpg

liftc1f.jpg
...

chromebumpers

Thread 'Valve Springs'

I met another neighbor yesterday. We started on cars and what he has in his barn, so he invited me over to give an opinion. He has a 1968 Nova with a 350 auto in great condition. I had to bite my lip to avoid asking if he would sell it. 1968s had the nicest dashboard and gauge setup of all the years. He’s interested in giving this car to his grandson (16) - after he finishes the help he promised to do around the house this summer. This grandson loves to clean the car when he comes to visit. Grandpa provides plenty of Pledge spray furniture Polish and a pile of old cotton clothes as...
  • Like

grumpyvette

Thread 'valve springs loads and installed height'

AmericanPie said:
Soon I'll be doing a mostly stock rebuild of the original 327/300 from my '65 Impala, using a mild (216/228 @ .050" dur., .454"/.480" lift) hydraulic Crane cam. I've been advised that Crane springs tend to be too strong for street use and will probably wear the cam prematurely. Is this true, and if so what would be a good choice in quality springs for this engine? This will be basically a street cruiser, w/ power peak of about 5500 rpm. Thanks!
Click to expand...

ASSUMING ALL VALVE SPRINGS FROM ANY SOURCE are too strong, too weak or anything else is absurd ! keep in mind the LAST THING any...

grumpyvette

Thread 'shaft rockers vs rocker stud girdles'

always call the cylinder head manufacturer for their input on rocker stud girdles,BEFORE PURCHASING THEM< because rocker stud spacing, and stud angles can vary, between head designs and models

READ THRU THIS THREAD ALSO

its not horsepower, its the stress on the valve train, that makes a rocker stud girdle and its increased rigidity useful,
and thats more closely related to average stress levels, RPM and VALVE SPRING LOAD RATES
any time your occasionally exceeding 6000rpm or getting close too 330 lbs of open valve load rate Id strongly suggest screw in rocker studs
any...
Click to expand...
@Grumpy I will have 3/8" trend pushrods and offset rockers. Possibly offset lifters
 
Indycars said:
@Christopher Williams

Have you checked out the master lobe profile catalogs. Most manufactures have one published. Here are two, Crower and Isky. For Crower the hydraulic rollers start on page 14 of 41. Mix & Match lobe for both intake and exhaust.

Click to expand...
Rick are you seeing more lives you want to Dyno ???
 
Are you set on hydraulic roller or a solid roller. Or maybe that's still up in the air.

I have another tool in Dynomation, it's called the Pro Iterator. I ran a session based on Maximum Area Under the Curve, thought that would be what you are after.

As you can see it runs a sim +-4°, 1° at a time. The it goes to the second phase with the 10 best and runs more sims at 4°/1° again. This will require running 13, 122 sims. It shows you the final 10 best sims. You check off the ones you want to save. This took about 15 minutes with the numbers I specified. It can go over 50.000 sims with the right parameterss

Check out the graphics below to see the one I ran based on your mystery cam. We could pick a different cam and run again. It's mainly just letting the compute crunch the numbers.

Iterator_02.jpgProIterator_02.jpg

ProIterator_03.jpg

Pretty cool , don't you think !

Got to run now, got to get ready to smoke about 20 lbs of meat. Including brisket, chicken bologna , pork butt and maybe some salmon

.
 
Rick I'm not set on either. I think I'm getting a bit aggressive for a hydraulic roller though. Unless we can find a close to 600hp hydraulic. I am moving to a 2.150 intake valve due to a seat issue. The heads will also move out to 227cc intake runners. I think the sim ran it with 210 runners and a 2.08 valve. So that may be the choke. 200" Lift: ~141 CFM Intake / 113 CFM Exhaust
.300" Lift: ~201 CFM Intake / 155 CFM Exhaust
.400" Lift: ~248 CFM Intake / 189 CFM Exhaust
.500" Lift: ~290 CFM Intake / 212 CFM Exhaust
.600" Lift: ~318 CFM Intake / 230 CFM Exhaust
.700" Lift: ~325 CFM Intake / 241 CFM Exhaust
.800" Lift: ~330 CFM Intake / 248 CFM
Are the flow numbers.
With a 1.7 rocker I will be at .681 lift. I think the sim ran it at .640 minus lash. .016 will be the lash, I originally thought it was .020 on this cam. I think with those numbers I will be 600+.
 
Summit is releasing these soon. Their hydraulic roller lineup looks decent as well. SR-3 looks driveable. I'm not opposed to a hydraulic roller either. Just need a lot out of it and the lifters
 

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I/O-17, I/C 49, E/O-59, E/C-15
.640 lift with 1.6
246/254 duration at .050. I'll have to use calculator for StS
109 LSA. Let me do some calcs for StS
 

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The Summit cam is too lazy with the lifter acceleration It' Hydraulic Intensity for the Summit cams is 29, while it's 24 for the Mystery Cam Makes for a significant difference in the area under the curve.

Dynomation rates the Summit cam at 2.84, Mystery Cam at 3.25 and the Crower at 5.07

1773600979361.png
Sim05-vs-Sim06.jpg
 
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The flow numbers are updated for both cam in the latest sim. I will try the 1.7 RR on the intake to see how that works. I will be after 10pm or tomorrow.
 
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id point out that the 1.7:1 rocker ratio puts both a considerably higher level of valve spring pressure on the rocker and cam to lifter contact area and its also slightly more prone to enter valve float at peak rpms from what i have seen , while the computer simulations may suggest its beneficial,
its been my experience that its also more likely to have both more rapid cam to lifter contact wear issues and valve control issues at peak rpms
yes I AM AWARE ITS A ROLLER LIFTER , ITS also heavier and the valve springs have a harder time keeping it in contact with the cam lobe after the lifter passes peak lift, and at high rpms the roller lifters inertia tends to resist the valve spring pressure just a bit longer and the lifter to lobe contact is not always consistent
 
Grumpy said:
id point out that the 1.7:1 rocker ratio puts both a considerably higher level of valve spring pressure on the rocker and cam to lifter contact area and its also slightly more prone to enter valve float at peak rpms from what i have seen , while the computer simulations may suggest its beneficial,
its been my experience that its also more likely to have both more rapid cam to lifter contact wear issues and valve control issues at peak rpms
yes I AM AWARE ITS A ROLLER LIFTER , ITS also heavier and the valve springs have a harder time keeping it in contact with the cam lobe after the lifter passes peak lift, and at high rpms the roller lifters inertia tends to resist the valve spring pressure just a bit longer and the lifter to lobe contact is not always consistent
Click to expand...
You aren't wrong there. Trying to figure out what is holding the Dyno program back. I'd think peak should be later. Just playing with numbers
 
Christopher Williams said:
Trying to figure out what is holding the Dyno program back. I'd think peak should be later
Click to expand...
I went searching for the answer. Tried changing serveral parameter and found the setting called "FE Exhaust Tune RPM", it made the biggest difference in the RPM at which the peak HP occurred.

I will get into tomorrow, getting too late to get started now.

NOTE: I corrected the labels and moved the graph to post #715 where it makes more sense.
 
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