My 422 smallblock build

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I don't like any of those cams lol. If I was picking my own cam for your build I would be having lunati grind me either an ultradyne NR109 or NR110 lobe intake and exhaust (straight duration) on a 108 ls depending on the compression ratio.

NR 109
.020 .050 w1.5
277 247 .623
NR 110
281 251 .623
 
So I saw you were planning on 10.75 compression, in that case I would not be afraid to run an ultradyne NR71 either.

NR 71
.020 .050 w1.5
284 255 .652

Basically I think anything from high 240s to mid 250s @.050 (depending on actual compression ratio), straight pattern, 108 ls and .620-.650 lift with 1.5s. That's my thinking,for whatever the hell that's worth lol.
 
lead69 said:
So I saw you were planning on 10.75 compression, in that case I would not be afraid to run an ultradyne NR71 either.

NR 71
.020 .050 w1.5
284 255 .652

Basically I think anything from high 240s to mid 250s @.050 (depending on actual compression ratio), straight pattern, 108 ls and .620-.650 lift with 1.5s. That's my thinking,for whatever the hell that's worth lol.
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I like that. A lot.
 
lead69 said:
So I saw you were planning on 10.75 compression, in that case I would not be afraid to run an ultradyne NR71 either.


NR 71
.020 .050 w1.5
284 255 .652

Basically I think anything from high 240s to mid 250s @.050 (depending on actual compression ratio), straight pattern, 108 ls and .620-.650 lift with 1.5s. That's my thinking,for whatever the hell that's worth lol.
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I’m leaning in the same direction but I think that ultradyne N71 may be just a whisker big for my application. I do think lift should be in the .615-.630 range before lash but I will probably keep duration down to 24x something. I also think lsa will be 108 or 109.
I’ve got it narrowed down to a fairly small window so I’ll probably just see who has a decent price on something within those numbers. I’m not loyal to any one brand or grinder.
 
I also agree with YR that the exhaust port seems to be working very well so a split duration is probably not needed.
 
If a grinder is using the same lobe series for both intake and exhaust the exhaust will show more lift with more duration
if the grinder developed separate lobes for the exhaust- which is currently the way to do it
then you may end up with a lobe that is a little longer but a little less lift or ???
depends on your head flows, open or closed exhaust, lots of things
SSG do not try and pick lSA yourself
it is the result of what your lobes are NOT an input
get the right timing and lobes to match the timing and lsa magically appears
seat timing is valve motion- start there and work back through your port flows to the cam



YR think about rocker arm specialists
I've had good results with their bushings, shafts, etc
agree on the cup adjusters
we may differ on oil through your new as big as you can fit pushrods
but will your oil squirts work?
 
I would add that the hardest thing to cam is a street driven four speed. Despite the differences in all the above cams on the dyno most of them would be within a few hp of each other at peak and in a correctly setup auto trans car would run almost identical at the track. But what about the power curves below peak and how that relates to a manual trans street car?. It needs to have grunt down low,in mid throttle situations and make good overall hp all without the help of a torque converter. That is where for me the tighter lsa comes into play, I have driven manual trans cars with 240/250 @ .050 cams and 3.91s/4.10s on the street and unless its a 455 pontiac the 110 and up lsa gives up drivability over the 108 and lower lsa everywhere under peak torque. I agree there is much more science in the end to picking cams/lsa but as has been proven time and time again if you are close on cam timing there is no big hp gain (I am talking street cars here not every tenth at the track). I will go with the cam that has a tighter lsa for the overall power curve down low in a street car and not worry about the negative effects on idle quality.
 
I'm telling you you're not going to like those super hi duration cams on the street... They're not going to gain you anyting but uncomfortable driving...
the 25% of the time that you say you'll be at the track which will probably be less than that you're not going to see more than a tenth or two better time at best...
 
Upon further review I think you'll be extremely happy with Ken's first recommendation..
You'll be able to go around a corner in second gear and pull out of it with plenty of low end..
 
lead69 basically the same thing AJ says
no converter to crutch the low end
and too much cam and your shifting down all the time
UDHarold always said most important point was the exhaust close he worked from there to the intake open- intake close- exhaust open
you can't get these from simple duration at .050 durations and a given lsa
Those are your inputs
 
j par said:
I'm telling you you're not going to like those super hi duration cams on the street... They're not going to gain you anyting but uncomfortable driving...
the 25% of the time that you say you'll be at the track which will probably be less than that you're not going to see more than a tenth or two better time at best...
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Im running 255 at .050 on the street and it’s easy to drive. Doesn’t buck, chug or anything else.

As to LSA I’m in 100% agreement it is the sum of events. A tighter LSA closes the exhaust earlier. So, for any given lobe, or pair of lobes and their duration, you move the LSA to change the events. It’s that simple.

Once you determine the total duration you need for your application, you set the opening point of the intake and the closing of the exhaust. That equals the LSA. You can have an LSA from say...102 to 116 with the same set of lobes. It’s all where the cam grinder sets them.

Again, the biggest killer of lower and mid range power is an LSA that is chosen (by the timing of the events) to smooth the idle or is used to reduce intake duration and keep the power after peak HP hang on longer.

And, if you are running headers, the wider LSA is even more of a detriment. That’s not me saying this, it’s Billy Godbold.
 
yellow rose said:
Im running 255 at .050 on the street and it’s easy to drive. Doesn’t buck, chug or anything else.

As to LSA I’m in 100% agreement it is the sum of events. A tighter LSA closes the exhaust earlier. So, for any given lobe, or pair of lobes and their duration, you move the LSA to change the events. It’s that simple.

Once you determine the total duration you need for your application, you set the opening point of the intake and the closing of the exhaust. That equals the LSA. You can have an LSA from say...102 to 116 with the same set of lobes. It’s all where the cam grinder sets them.

Again, the biggest killer of lower and mid range power is an LSA that is chosen (by the timing of the events) to smooth the idle or is used to reduce intake duration and keep the power after peak HP hang on longer.

And, if you are running headers, the wider LSA is even more of a detriment. That’s not me saying this, it’s Billy Godbold.
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all that Guru stuff sounds fascinating but all I know is when I had a really high duration it ran like crap on the street till it hit three grand and then it went off like a bat out of hell.. couldn't go around the corner and second gear and pull it out from low RPMs without it clattering and sounding awful. Now that my duration is much more under control so is everything else and I didn't lose but a few tents at the track if that...
 
I remember with my old cam my best friend went for a drive with me and at first he didn't think we were going to make it home the car was running so bad but then when I opened it up he was holding on for dear life and when we got back home he had a big smile...
Again ran like crap under 3K but that was my experience it sounds like you're having a much better one...
 
j par said:
I remember with my old cam my best friend went for a drive with me and at first he didn't think we were going to make it home the car was running so bad but then when I opened it up he was holding on for dear life and when we got back home he had a big smile...
Again ran like crap under 3K but that was my experience it sounds like you're having a much better one...
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When you ran your old big duration cam did you happen to pull a compression test?
Is so, what kind of cylinder pressures did you see at cranking speed?
 
j par said:
187-197... Now 205-215..
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Interesting, so perhaps it could be said that a cam that allows the engine to develop relatively high cranking speed cylinder pressures may relate to poor low speed driveability. Obviously there are other factors like compression ratio and fuel that come into play. The point being that the OP may want to take this in to consideration when making his cam selection.
 
j par said:
My first cam on a 107 had a 259-267 duration with a with a 582-603 lift with 1.6 to 1 rockers... 546-566 Lift when I had Factory 273 rockers... Mechanical solid lifters I'm about 11.3 to 1 compression....
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The duration and the cam timing make that cam much bigger than any of the cams discussed above. It had a lazy lobe looking at the lift,and an 8 degree spread. I'm betting the recommended lash was at least .028 or so?, not picking on the cam just saying the fact is that is not a street friendly grind at all (especially compared to modern lobes).
I have an ultradyne 247/250 108 ls solid ft cam in my 410 and with 10.5 compression and it idles good at 900 and has a ton of street manners, and even cleans up around 2k with no lugging at all with my overdrive four speed.
 
512Stroker said:
Interesting, so perhaps it could be said that a cam that allows the engine to develop relatively high cranking speed cylinder pressures may relate to poor low speed driveability. Obviously there are other factors like compression ratio and fuel that come into play. The point being that the OP may want to take this in to consideration when making his cam selection.
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One thing I got to say on this subject is when I talked to Ken the first time for the first cam I convinced them I knew what I wanted and he gave it to me LOL... honestly at first it was kind of cool and great at the track but as I found out the track was expensive and driving on the street was a lot less expensive I started finding out how undesirable the cam became on the street...
That was a learning experience. The next time I went to him we had another long discussion and I told him how I'd like it to idle better but I'd like it to not lose all of its mojo... Suggestion and I went with the current grind and I'm happy with it.. if I was to redo it again I may give a little more lift, but the duration seems fine...
That's what drew me to the conclusion that his first recommendation would probably be the best...
 
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lead69 said:
The duration and the cam timing make that cam much bigger than any of the cams discussed above. It had a lazy lobe looking at the lift,and an 8 degree spread. I'm betting the recommended lash was at least .028 or so?, not picking on the cam just saying the fact is that is not a street friendly grind at all (especially compared to modern lobes).
I have an ultradyne 247/250 108 ls solid ft cam in my 410 and with 10.5 compression and it idles good at 900 and has a ton of street manners, and even cleans up around 2k with no lugging at all with my overdrive four speed.
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Yes it was what I wanted for the track and didn't clean up till 3 Grand but the cam that I have now is clean from idol..
 
what yr said
Once you determine the total duration you need for your application,
you set the opening point of the intake and the closing of the exhaust.

I posted this somewhere
UDHarold -designed the Ultradyne lobes held that the exhaust close was the place to start- then the intake open
exhaust you are solving reversion and exhaust makes a big difference- you want the exhaust going out the exhaust
which gives you when you can open the intake without reversion- you have to know what your low lift flow is when the exhaust is sucking and piston speed is up or slow
and rod/stroke does make a difference
go o around the other events and determine your seat= timing
that gets you to your duration which determines your rpm range
rpm range wrong- go around again
.050 is useless except to degree the cam
 
j par said:
Yes it was what I wanted for the track and didn't clean up till 3 Grand but the cam that I have now is clean from idol..
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Somehow I missed it
What are the spec's of the cam you are running now?
Manual or auto trans?
 
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