Stroker specific cams?

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DrEamer said:
Fuel mileage is not a true concern for me. I figure if it gets 12-14 mpg then I'll be fine. I hope for more with the overdrive transmission, but fun per mile is more what I am looking for.
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OK, just one more thing that influences LSA.... or maybe I should say changes things in a way that ends up with a wider LSA. Ditto for emissions... but I don't need to guess where your thoughts are on THAT! LOL

Having more gears always helps in a lot of way. Since turbo rally cars have to run restrictors, they moved to 6 and 7 speed trannies and had electronic paddle shifters at least 15 years ago. I rented a 2018 Ford Expedition last fall... 2.7L turbo with a 10 speed auto trans!
 
nm9stheham said:
OK, just one more thing that influences LSA.... or maybe I should say changes things in a way that ends up with a wider LSA. Ditto for emissions... but I don't need to guess where your thoughts are on THAT! LOL

Having more gears always helps in a lot of way. Since turbo rally cars have to run restrictors, they moved to 6 and 7 speed trannies and had electronic paddle shifters at least 15 years ago. I rented a 2018 Ford Expedition last fall... 2.7L turbo with a 10 speed auto trans!
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100% FACT. Less gears means you move the cam timing to flatten out the power curve, which opens up the LSA.

Funny story. I was in the local speed shop bench racing a couple of friends. Two other guys walk in to buy some spark plugs. I had talked to them many times at the track so we started talking. They were on their way back to the dyno. They had been on the dyno all day the day before and all of that day. They were almost done, but needed more plugs to finish up.

I asked what the engine did. I knew it was 500 plus inches, but not the exact displacement. This is 1987. Alcohol injected BBC. They said it went 990 at 7000, but they were going to knock it back to 880-900ish so they could put more area under the curve and move peak down.

I'm like why would you do that, after all that work to make power. He said one word...powerglide.

They had switched from a TH to a PG and figured two gears would be faster with less HP and a broader power curve.

I still say he was nuts, because we all know if you can get it hooked, three gears is faster than two.

Sadly, the guy who owned and drove the car killed himself in a single car drunk driving crash. I think they made about 5 shake down runs on it before he died.

Just pointing out that gears make cam timing changes that end up opening the LSA.

I also think about over head cams. You can move the cams where you want. And that moves the LSA, and changes the cam timing. One always follows the other.
 
yellow rose said:
100% FACT. Less gears means you move the cam timing to flatten out the power curve, which opens up the LSA.
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So, if I understand you correctly, a wider spread LSA is good for fewer gear. Then how does something like my A518 automatic figure into that with its overdrive?
 
DrEamer said:
So, if I understand you correctly, a wider spread LSA is good for fewer gear. Then how does something like my A518 automatic figure into that with its overdrive?
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I'm saying the fewer gears require different timing events, and that in turn will make the LSA wider.

Yours is a good question. If it were me, I'd cam it for the 3 non overdrive gears and let the OD do its job.

Before I did that though, I'd call a cam guy I trust and ask him.
 
yellow rose said:
I'm saying the fewer gears require different timing events, and that in turn will make the LSA wider.

Yours is a good question. If it were me, I'd cam it for the 3 non overdrive gears and let the OD do its job.

Before I did that though, I'd call a cam guy I trust and ask him.
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But.. but but, I thought you were the cam guy I could trust !!:rofl: All kidding aside, I have been emailing with Chris Padgett at Bullet, and so far he has been able to answer all my questions. I have also emailed Jones, and I know that a lot of people thinks they are the best, but I'm not sure of the whole inverse radius thing.
 
DrEamer said:
But.. but but, I thought you were the cam guy I could trust !!:rofl: All kidding aside, I have been emailing with Chris Padgett at Bullet, and so far he has been able to answer all my questions. I have also emailed Jones, and I know that a lot of people thinks they are the best, but I'm not sure of the whole inverse radius thing.
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LOL. Yeah, I don't do much stuff with OD so that one caught me off guard!!!
 
DrEamer said:
... but I'm not sure of the whole inverse radius thing.
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Might be different now but back in the day, yes, IR cams made the most power and were used to race winning effect in 5000cc Aus Touring Car engines but were also the hardest on springs and roller tappets. JM2CW.
 
DrEamer said:
So, if I understand you correctly, a wider spread LSA is good for fewer gear. Then how does something like my A518 automatic figure into that with its overdrive?
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The fewer gears goes back to needing a wider torque curve, so you don't 'fall off the curve' with gear changes..... and the wider, flatter curve is helped by a wider LSA....ooops, by timing events that result in a wider LSA. Keep up torque at the very low RPM end so you get a lower 'low end' of the RPM range, and thus a larger high-to-low RPM ratio of usable torque. It's not as much of a deal with an auto if you are willing to use a higher stall TC, but it IS a big deal with a manual trans.

(FWIW.... a high stall TC kinda sucks for spirited curvy road driving, as the RPM where the TC 'catches' to give just the right amount of wheel torque at a given moment is less predictable. Some modern trannies like those used in the Challenger have worked around the TC lock-up 'mushiness' by locking the TC (or very close to locking) when you go into manual shift mode, to make the engine much better coupled to the rear wheels all the time.)
 
I have been discussing this whole cam selection with another member here via PM's. We went over the combination in fairly good detail, and he came up with something similar to the Jones cam, without the IR lobes. I might be able to get more power out of the IR's, but I also will be able to use non proprietary lifters without fear of valve train wear issues. The one thing that once again came up is the use of a single pattern cam. I found an article from Engine Builder Magazine mentioning that single patterns are becoming more prevalent as the newer generation of heads have better exhaust flow then those of the past. Thereby, decreasing the need for split duration cams. I know that this may have been covered in this thread somewhere, but good to see it elsewhere. It is a basic article to a lot of folks here, but good information for those of us not as well versed in these things. Link provided below.

Choosing the Correct Camshaft - Bangin' on the Bumpstick - Engine Builder Magazine
 
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nm9stheham said:
OK, just one more thing that influences LSA.... or maybe I should say changes things in a way that ends up with a wider LSA. Ditto for emissions... but I don't need to guess where your thoughts are on THAT! LOL

Having more gears always helps in a lot of way. Since turbo rally cars have to run restrictors, they moved to 6 and 7 speed trannies and had electronic paddle shifters at least 15 years ago. I rented a 2018 Ford Expedition last fall... 2.7L turbo with a 10 speed auto trans!
Click to expand...

YEAH , MY WIFES IS IN THE SHOP NOW GETTING A NEW SHORT BLOCK , 50,000 ON THE CLOCK >But she likes fords because her dad used to work for them--------
 
I have made such mentions before (I don’t know if I did in this thread, doesn’t matter....) and have stated why there is a good use for, and the reason behind a split duration cam. Before or After your heads are ported, they should be flowed to understand the balance between the intake and exhaust ports where you should then find the balance percentage ratio between them both. Once this is known along with the rest of the engine package, you can determine the amount of split you may want to run effectively.

It is certainly, IMO, that running the maximum amount of lift or radical lobe as per your lifter diameter isn’t necessary for every engine. Nor is running a split duration cam always needed for an excellent result. The need to take maximum advantage of every aspect of an engine isn’t always a warranted or must do and use venue to take. Taking this road can lead to vale train issues like noise, early spring replacement, etc....
There is also the characteristics of the cam itself which you may not like. Often I have seen fellas replace a cam on that alone. Mainly due to the car being driven very often rather than raced. If your exhaust ports demonstrate excellent flow, a reduced exhaust duration will not hurt a thing.

Good article link. Glad you put it up. Which I’m now going to read...LOL

(Edit; That was a good (& quick) informative read.)

DrEamer said:
I have been discussing this whole cam selection with another member here via PM's. We went over the combination in fairly good detail, and he came up with something similar to the Jones cam, without the IR lobes. I might be able to get more power out of the IR's, but I also will be able to use non proprietary lifters without fear of valve train wear issues. The one thing that once again came up is the use of a single pattern cam. I found an article from Engine Builder Magazine mentioning that single patterns are becoming more prevalent as the newer generation of heads have better exhaust flow then those of the past. Thereby, decreasing the need for split duration cams. I know that this may have been covered in this thread somewhere, but good to see it elsewhere. It is a basic article to a lot of folks here, but good information for those of us not as well verse in these things. Link provided below.

Choosing the Correct Camshaft - Bangin' on the Bumpstick - Engine Builder Magazine
Click to expand...
 
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DrEamer said:
I have been discussing this whole cam selection with another member here via PM's. We went over the combination in fairly good detail, and he came up with something similar to the Jones cam, without the IR lobes. I might be able to get more power out of the IR's, but I also will be able to use non proprietary lifters without fear of valve train wear issues. The one thing that once again came up is the use of a single pattern cam. I found an article from Engine Builder Magazine mentioning that single patterns are becoming more prevalent as the newer generation of heads have better exhaust flow then those of the past. Thereby, decreasing the need for split duration cams. I know that this may have been covered in this thread somewhere, but good to see it elsewhere. It is a basic article to a lot of folks here, but good information for those of us not as well versed in these things. Link provided below.

Choosing the Correct Camshaft - Bangin' on the Bumpstick - Engine Builder Magazine
Click to expand...


I'll post this here and then get ready to take my lumps.

Exhaust flow is really a non factor in cam selection. Seriously. Flowing an exhaust port and believing the numbers is a sure fire way to make the port way too big. BTDT. A flow bench will tell you to make the port bigger and bigger. The port may be dirty, noisy and screaming loud (none of which you see on the sheet you get with numbers on it) but man, I'm flowing 85% of the intake so I'm smoking this deal.

And then on the dyno you are opening the exhaust lash and the power is going up. Then you advance the cam and the power curve goes UP!!! And you think WTF? The port is just too big. Probably the valve too.

So picking a single pattern cam based on exhaust flow doesn't make sense.

I've posted this before. What you see with dual pattern cams is not more exhaust duration. It's LESS intake duration. Then, to make the engine RPM where the customer wants' the cam grinder moves the timing and opens the LSA up so it will have more HP after peak. I've been battling with this for a long time. It's hard to get the cam guys to admit what they do. Thanks Comp.

So I'm all for single pattern cams. And don't forget, you can have an intake lobe that's 250 at .050 with .350 lobe lift and an exhaust lobe with the same numbers and two very different lobes.
 
An old gasser guy I knew always told me to worry about gettin it in and it will find its way out. Talking about cams and cylinder heads of course.
 
Cal Tonsley said:
So just wondering what cam was chosen in the end? Or is this still to be decided?
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Still looking at options, I just recieved a grind list from Oregon Cam Grinders, have some that look interesting, but will confer with Ken on those. Also, have looked at Lunati and a few others, but hearing back from most of these places seems like they don't want to email you back. What use is their cam recommendation form if they will not answer it? Jones, Bullet and Oregon Cam have been the exception to that, and am leaning towards them since they seem to want my business.

I'm kind of wondering how your Pro-Flo system is working with the TFS heads, since I plan on going that way and feedback would be appreciated. Also, I hope you are safe and out of the fire zone!
 
DrEamer said:
Still looking at options, I just recieved a grind list from Oregon Cam Grinders, have some that look interesting, but will confer with Ken on those. Also, have looked at Lunati and a few others, but hearing back from most of these places seems like they don't want to email you back. What use is their cam recommendation form if they will not answer it? Jones, Bullet and Oregon Cam have been the exception to that, and am leaning towards them since they seem to want my business.

I'm kind of wondering how your Pro-Flo system is working with the TFS heads, since I plan on going that way and feedback would be appreciated. Also, I hope you are safe and out of the fire zone!
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Just curious, do you have an idea on where you should be regarding cam specs for your setup? What will be the determining factors on choice of grinder if for example you get three different cams spec’d with differing durations, lsa’s, lifts rates, etc yet they all sound good as explained, in theory and on paper? Decisions decisions!
 
IDK that Jones really needs special lifters but I know he does not like some brands
bigger wheel is better
IDK if comp makes a MOPAR xfi lobe- I looked one time but I forget
old IR lobes sucked and were not very IR, some just as IR as could be ground on a production wheel- sort of an advertising ploy
personally In later years I made more boat and motorhome motors than hot street stuff
but here goes
I found that making the intake bigger and better even at the expense of the exhaust (flow wise) works
I found that .050 flow tells me when i have to open the intake valve to get the flow started at overlap, exhaust pull, and all that.
along with that a long rod mopar is quite different than a short rod sbc or bbc
they have to start opening the intake earlier to get it open where it counts
valve job makes a big difference
I pulled dyno down way below 2500 as I was using torque converters that I had to have locked up down there
I have not tried these late high stall converters and how they might not slip in a heavy vehicle, heat and all that
something OP needs to keep in mind
flat flank roller can make the same peak hp but that's not where it's at
IR can have shorter seat timing and therefore more torque at the same rpms
look at 200
interesting the UD harold said his mopar 256 cam was 5-6 degrees bigger than his chevy 256
why leave 5-6 degrees on the table
difference may be bigger on bigger cams
great thread
cheers
 
DrEamer said:
Still looking at options, ……………I'm kind of wondering how your Pro-Flo system is working with the TFS heads, since I plan on going that way and feedback would be appreciated. Also, I hope you are safe and out of the fire zone!
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Thanks for the update, no more news on my ProFlo unit I’m afraid - still in the middle of the car build and while the engine is complete it’s still a while off running! Bodywork / paint / wheel tubs etc now all pretty will finished and just putting together a shortened 8 3/4 rear end for it and then the final construction can commence. This will likely take most of the year I guess but I’ll definitely keep you updated! All the best in the meantime.

PS Fires have been close at times but unlike some we have been safe and lucky, appreciate your kind thoughts!

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12many said:
Just curious, do you have an idea on where you should be regarding cam specs for your setup? What will be the determining factors on choice of grinder if for example you get three different cams spec’d with differing durations, lsa’s, lifts rates, etc yet they all sound good as explained, in theory and on paper? Decisions decisions!
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Maybe I have been watching too much Engine Masters and overthinking this, but here is what I have concluded about my project. I have already the two easiest ways of making horsepower and torque covered. First was going with a stroker, and second going with the best heads for the money I can afford. Since the car is a street only car that will never see over 6,000 RPM, big duration is overkill. Also, since I plan on using a roller hydraulic I would probably not want to rev it very much past my stated RPM range anyway. My goal is not to have a spring killer cam, and it needs to be drivable with good vacuum. Those factors point to milder ramps, and possibly wider lobe separation then what many posters might consider as necessary, but I am willing to give up a little horsepower to meet my goals.
 
@DrEamer

I think that is sound thinking.

1: You can’t beat a stroker. Or just simply, the old saying is true, there really is no replacement for displacement.

2: The better the cylinder head, the better the power release can be. Essentially, if the engine can’t breath, then it can’t make power. Back this up with an excellent intake and exhaust and you’ll be in great shape.

On a cam, you have to get one that fits the build and one that’s good for YOU! The driver, the one that has to live with it.

My only advice when your figuring out the cam for your ride is at the least, get a cam that will lift the valve up high to take advantage of the heads capability. Horse power will follow.

Best wishes on your build, enjoy!
 
enjoyed your write up
so two combinations to work up
compression, quench and cam back of the comp a little, tighten the quench- cam duration to match rpm range
trans and gears what's your rpm drop at shift
what rpm cruze, OD?
you know those engine masters usually run a big rocker- need to decide that
two choices: major difference in cost
roller tip rockers and B3 Kit
vs Iron rockers
with either plan on cups on the adjusters and ball and ball pushrods with oil through
do you have a roller block (not reading the whole thread)
if so does anyone make a hyd roller with a .810- or larger wheel
or are you stuck with .700 so pick your vendor
I know that only one mfg makes all the retrofit lfters and they are all small wheel -AFIK
SPrings- Ron at Isky just told a poster that he prefers duals to beehives with HR
Ron's a sharp guy and sells both so take that into consideration
you may also want to pm dart19666 at Crower and see what he thinks and others that have Mopar enthuisam
Cam Mike Jones- and then let him pick the lifters and springs- ask Krooser why
did you post your head flows? if you have not flowed them yet then do .050 also
long rods? anything else? his computer program can match the compression and cam
cheers
going to run great
 
Wyrmrider said:
enjoyed your write up
so two combinations to work up
compression, quench and cam back of the comp a little, tighten the quench- cam duration to match rpm range
trans and gears what's your rpm drop at shift
what rpm cruze, OD?
you know those engine masters usually run a big rocker- need to decide that
two choices: major difference in cost
roller tip rockers and B3 Kit
vs Iron rockers
with either plan on cups on the adjusters and ball and ball pushrods with oil through
do you have a roller block (not reading the whole thread)
if so does anyone make a hyd roller with a .810- or larger wheel
or are you stuck with .700 so pick your vendor
I know that only one mfg makes all the retrofit lfters and they are all small wheel -AFIK
SPrings- Ron at Isky just told a poster that he prefers duals to beehives with HR
Ron's a sharp guy and sells both so take that into consideration
you may also want to pm dart19666 at Crower and see what he thinks and others that have Mopar enthuisam
Cam Mike Jones- and then let him pick the lifters and springs- ask Krooser why
did you post your head flows? if you have not flowed them yet then do .050 also
long rods? anything else? his computer program can match the compression and cam
cheers
going to run great
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So in keeping with my simple is better for my street engine project, I have a Magnum roller block that I plan using an OE lifter. They run them well into .580 lift range, plus are easy to source if one fails. That rules out a Jones cam, I'm not getting into proprietary parts just for the sake of more power. As far as the rockers, B3 sells PRW rockers with his correction kit, the price is reasonable compared to others, and comes in 1.5 or 1.6 ratios. My reference to Engine masters was the Motor trend show, not the competition series. Below are the flow numbers for the Trick flow heads.

Lift Value Intake Flow CFM Exhaust Flow CFM
.100" 66 54
.200" 134 121
.300" 200 181
.400" 248 213
.500" 281 231
.600" 293 237
.700" 301 240
 
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