Cam opinions 418

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4eighteener

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I know what they say about opinions, but i am having some indecision paralysis regarding a cam, and if i can't ask here, where can I ask?
It also meshes with another post on LSA.
What i got;
72 340 block ..040
Hughes low compression stroker kit.
Dished hypereutectic pistons
Scat rods
Scat cast crank
10.17 static compression
0 deck height
Trick flow 190 with 1.46 springs (120 seat)
1.6 roller rockers

Vehicle:
1986 dodge ramcharger 4x4
6000lbs
A727 non lock up
3.23 rear
2500 hughes stall convertor
33x12.5 tires

Uses:
To Vermont and back twice a year highway (snow bird)
Some trailer towing 4500lbs
Around town driving florida, a few feet above see level
Around town driving Vermont with a steep dirt driveway up to 800'
General truck use

Dream use:
Drive to Utah/Colorado and drive some easy off road trails and drive back.
Dependable

So, i have put this together twice with flat tappets cams that have failed in the first 100 miles.
I am determined to avoid that again and going hydraulic roller this time.
I contacted Howard and filled out their cam recommendation form and waited a week and they came back with their #711915-12 hydraulic roller cam.
Specs:
274-278 advertised
221-225 @ .050
474-500 lift at 1.5
112 LSA
Operating range 1200-5700
Mild idle, low end torque, 9.5 comp required
In at 108°

Now summit only had 3 roller cams of any type available available, and that happened to be one of them, so i am not sure if that is the best choice, or just the best choice of what is available. I asked for the intake valve abdc number to plug into wallace to determine dynamic compression and cylinder pressure, but have not heard back yet, and not found anything online.
Anyway, I guess I had in my mind something like a BTR cam with lower duration, more lift, and and tighter lsa, like their 107.5 lsa 112 duration, and over .550 lift.
Opinions? anyone run this cam?
 
#1 - AWESOME tow rig. We need pictures.

#2 - go with the Howards recommendation. I run one of their solid rollers and I love it. Bonus that it’s in stock at Summit. Just verify it will play nice with your current valve springs.
 
I don't have to many pictures of the outside, tons of the engine rebuild though.
Rust free, great interior, decent paint.
The springs howards recommends for that cam has similar specs to the pac springs that come on the head.
I did find a table on the wallace racing calculator site where it would determine your valve events from the cam specs.
It came up with a abdc of 65, which when I plug into their dynamic ratio calculator gives me like 8:1 dynamic compression ratio and 165 cylinder pressure.
Pretty low for aluminum heads

IMG_20190703_162124.jpg
 
The grind Howard’s recommended fits the bill almost perfectly for a driver on big tires, low stall, high gears and big big torque. And it will have a nice daily driver idle with the wide LSA. It’s about perfect for what you want to do. If your engine had 12:1 and was in a 3000lb dart with a 5000 stall and 4:56 gears you’d pick something entirely different.
 
TT5.9mag said:
The grind Howard’s recommended fits the bill almost perfectly for a driver on big tires, low stall, high gears and big big torque. And it will have a nice daily driver idle with the wide LSA. It’s about perfect for what you want to do. If your engine had 12:1 and was in a 3000lb dart with a 5000 stall and 4:56 gears you’d pick something entirely different.
Click to expand...
Well, that two who like the cam choice who's opinions here on FABO I respect.
Perhaps i am just a little gun shy and don't want to do this again anytime soon.
 
4eighteener said:
Well, that two who like the cam choice who's opinions here on FABO I respect.
Perhaps i am just a little gun shy and don't want to do this again anytime soon.
Click to expand...
I look at camshafts a little differently than most people. I’ll change a cam in an engine a week after I put it in if I don’t like it. Most people think they’re stuck with it. That being said, you gotta start somewhere to see what it does, and you could start with a whole lot worse than that Howard’s cam.
 
4eighteener said:
I don't have to many pictures of the outside, tons of the engine rebuild though.
Rust free, great interior, decent paint.
The springs howards recommends for that cam has similar specs to the pac springs that come on the head.
I did find a table on the wallace racing calculator site where it would determine your valve events from the cam specs.
It came up with a abdc of 65, which when I plug into their dynamic ratio calculator gives me like 8:1 dynamic compression ratio and 165 cylinder pressure.
Pretty low for aluminum heads

View attachment 1716330268
Click to expand...

Nice ride. I myself would still look for a more narrow LSA.
David Vizard has a formula that works very well and was shown on Engine Masters on the cam experiments they did. The lower LSA mom er provided more torque until the engine can up on the cams intended RPM range. The narrower LSA starts the air and fuel coming in quicker. At your exact unknown cubic inch engine, a 408 with a 2.02 valve is looking for a LSA of 105.02. DV suggest going down 1 number if it’s split between the normally seen even numbers. But you can have that custom cut for you if you wish.

A 408 w/a 2.08 valve is asking for a 105.68 LSA.
Personally a degree ether way is not going to be noticed and hard to see in a dyno graph.

Now a lot of people are going to jump to a conclusion here and say the idle will be a chopping PIA to tune and drive down low with. This is simply not the truth because the amount of overlap the cam has will be small because the duration- advertised and @ .050 will be small limiting the amount of overlap.

Also, FWIW, a header collector extension the same size as the collector (not the reduced that bolts to the header at the collector) should be added into a torque cancellation box to mimic the exhaust exiting into the open air. This makes max torque down low which a heavy vehicle like the Ram Charger will really like at no extra fuel used. Your just making the most of what is available with minor fabrication work.

PS, if your more than 408 cubes, it’s not going to matter much. If you were at 434 cubes, there is a small difference worth looking into.


What finishes the engine up? RPM & a 750? 1-3/4 headers?
 
Okay, cool! Thanks for the opinion!
The lifter was a summit brand. I had a couple of 318 builds using them and didn't have a problem, so i am shooting 50% for cam success.
The hughes cam i already had on the shelf without lifters and in order to take advantage of their. "no flat cam guarantee ", you need to buy the cam, lifters, and break in oil all at the same time.
Anyway, I hope I am past that now
 
I hope your past that too. The only time I had a cam and lifter go bad on me was with a Summit brand set up. Well, I can’t blame the Summit set up at all, because I know what I didn’t do and I got what I deserved, it is the only time I’ve had, a cameo flat on me in 35 years. I never understood what all the fuss was about. I had broken in several camshafts during all the irate postings throughout the various forms without issue.

Hughes has a great guarantee and their parameters of buying all of their material isn’t a bad one. Some people squawk about that but I think it’s good insurance from Hughes that if you have their stuff and follow their instructions, you will have a successful camp break in. Their rules are simple. At least they know where the stuff came from and not some Johnny Joe crap is being used in place of the quality stuff they have.

I think Hughes has some really nice grinds. Also, Howard and Schneider cams. Really nice specifications on them. I personally don’t think you can go wrong with either three.

To me, as long as the engine has good machining, bill practices, is clean as a whistle, and you follow proper can break in procedures. I really don’t know why anybody has had a problem. I know **** happens! But it’s never happened to me without me, knowing why. Like I said, my one and only cam failure that I had, I know where to put the blame. Me!

If you get a chance to read David Bard‘s writings on camshafts and watch the engine, Masters episode where they test camshaft LSA‘s as well as the header extension test they did with two different size headers, I think you have an excellent engine that produces a healthy amount of low torque.

Enjoy your build happy motoring!
 
rumblefish360 said:
Nice ride. I myself would still look for a more narrow LSA.
David Vizard has a formula that works very well and was shown on Engine Masters on the cam experiments they did. The lower LSA mom er provided more torque until the engine can up on the cams intended RPM range. The narrower LSA starts the air and fuel coming in quicker. At your exact unknown cubic inch engine, a 408 with a 2.02 valve is looking for a LSA of 105.02. DV suggest going down 1 number if it’s split between the normally seen even numbers. But you can have that custom cut for you if you wish.

A 408 w/a 2.08 valve is asking for a 105.68 LSA.
Personally a degree ether way is not going to be noticed and hard to see in a dyno graph.

Now a lot of people are going to jump to a conclusion here and say the idle will be a chopping PIA to tune and drive down low with. This is simply not the truth because the amount of overlap the cam has will be small because the duration- advertised and @ .050 will be small limiting the amount of overlap.

Also, FWIW, a header collector extension the same size as the collector (not the reduced that bolts to the header at the collector) should be added into a torque cancellation box to mimic the exhaust exiting into the open air. This makes max torque down low which a heavy vehicle like the Ram Charger will really like at no extra fuel used. Your just making the most of what is available with minor fabrication work.

PS, if your more than 408 cubes, it’s not going to matter much. If you were at 434 cubes, there is a small difference worth looking into.


What finishes the engine up? RPM & a 750? 1-3/4 headers?
Click to expand...
Yes, it is 418 cubic inch, but close enough with a 2.02 valve to your 408 example with the tighter lsa.
I knew i would be forgetting something on the specs.,
I have the hooker ceramic coated 1 5/8" headers for exhaust connected to 2 1/2" duel exhaust with walker.
The weak link is the intake and carburetor. I am using the straight performer intake because it allows the use of the center mounted ac compressor due it its offset gooseneck. I gasket matched it maybe a 1/2" just so there wouldn't be such a large port mismatch between the trick flow ports and the manifold. I would like to swap out to the rpm air gap as soon as I can figure out the bracketry for it that will allow me to keep my ac, as you know, a necessity in Florida.
I do have a holly 750 vacuum second carburetor for it, but I have been using a summit 650 carburetor with the annular boosters. It hasn't been running long enough to swap and compare, but i thought the boosters might make it more responsive and get better fuel economy on long trip north.
 
4eighteener said:
Okay, cool! Thanks for the opinion!
The lifter was a summit brand. I had a couple of 318 builds using them and didn't have a problem, so i am shooting 50% for cam success.
The hughes cam i already had on the shelf without lifters and in order to take advantage of their. "no flat cam guarantee ", you need to buy the cam, lifters, and break in oil all at the same time.
Anyway, I hope I am past that now
Click to expand...
Hughes sucks .
 
4eighteener said:
Yes, it is 418 cubic inch, but close enough with a 2.02 valve to your 408 example with the tighter lsa.
I knew i would be forgetting something on the specs.,
I have the hooker ceramic coated 1 5/8" headers for exhaust connected to 2 1/2" duel exhaust with walker.
The weak link is the intake and carburetor. I am using the straight performer intake because it allows the use of the center mounted ac compressor due it its offset gooseneck. I gasket matched it maybe a 1/2" just so there wouldn't be such a large port mismatch between the trick flow ports and the manifold. I would like to swap out to the rpm air gap as soon as I can figure out the bracketry for it that will allow me to keep my ac, as you know, a necessity in Florida.
I do have a holly 750 vacuum second carburetor for it, but I have been using a summit 650 carburetor with the annular boosters. It hasn't been running long enough to swap and compare, but i thought the boosters might make it more responsive and get better fuel economy on long trip north.
Click to expand...
You have a performer intake on a 418 with trick flows with a 650 carb? I’ll like to change my previous answer, it makes really no difference what camshaft you put in that engine. It will never be what is holding it back.
:lol:
 
rumblefish360 said:
I hope your past that too. The only time I had a cam and lifter go bad on me was with a Summit brand set up. Well, I can’t blame the Summit set up at all, because I know what I didn’t do and I got what I deserved, it is the only time I’ve had, a cameo flat on me in 35 years. I never understood what all the fuss was about. I had broken in several camshafts during all the irate postings throughout the various forms without issue.

Hughes has a great guarantee and their parameters of buying all of their material isn’t a bad one. Some people squawk about that but I think it’s good insurance from Hughes that if you have their stuff and follow their instructions, you will have a successful camp break in. Their rules are simple. At least they know where the stuff came from and not some Johnny Joe crap is being used in place of the quality stuff they have.

I think Hughes has some really nice grinds. Also, Howard and Schneider cams. Really nice specifications on them. I personally don’t think you can go wrong with either three.

To me, as long as the engine has good machining, bill practices, is clean as a whistle, and you follow proper can break in procedures. I really don’t know why anybody has had a problem. I know **** happens! But it’s never happened to me without me, knowing why. Like I said, my one and only cam failure that I had, I know where to put the blame. Me!

If you get a chance to read David Bard‘s writings on camshafts and watch the engine, Masters episode where they test camshaft LSA‘s as well as the header extension test they did with two different size headers, I think you have an excellent engine that produces a healthy amount of low torque.

Enjoy your build happy motoring!
Click to expand...
I felt i did everything right with the break in, checking the lifters for crown, checking the cam for taper, checking that the lifters rotated in their bores, using a quality cam break in lube, using the correct break in oil, pre-oiling the engine, did the hughes oiling mods, a quick start up, 20 minutes of break-in between 2000 and 2500 rpm, driving it around towj in short trips.
Both cams failed when I took them on the highway, which was around 2200 rpm at 65 mph.
I did everything recommend except for swapping to a lighter pressure spring during the break in.
I don't consider the 120 lbs seat pressure excessive, but if I did everything else right, that was the only thing I didn't do. Again, everything broke in fine, it was only upon highway use they failed.
Anyway, I hope I am past that now.
 
TT5.9mag said:
You have a performer intake on a 418 with trick flows with a 650 carb? I’ll like to change my previous answer, it makes really no difference what camshaft you put in that engine. It will never be what is holding it back.
:lol:
Click to expand...
No changing answers!
I don't believe the carb is as bad as the manifold though for airflow restriction.
I would love to see a dyno graph of the drop off above 4000 rpms.
 
4eighteener said:
No changing answers!
I don't believe the carb is as bad as the manifold though for airflow restriction.
I would love to see a dyno graph of the drop off above 4000 rpms.
Click to expand...
I’d bet with an air gap, a 750 double pumper and a roller cam change you could pick up 65hp or so. I bet it falls off a cliff at 4500
 
4eighteener said:
No changing answers!
I don't believe the carb is as bad as the manifold though for airflow restriction.
I would love to see a dyno graph of the drop off above 4000 rpms.
Click to expand...
it probably doesn't fall off a cliff straight away but plateaus till like 5, mayyybe 52 and then just stops making power.

the 650 is probably great for fuel mileage and i'd bet it's super crisp throttle wise around town, but that's not doing you any favors.
 
junkyardhero said:
it probably doesn't fall off a cliff straight away but plateaus till like 5, mayyybe 52 and then just stops making power.

the 650 is probably great for fuel mileage and i'd bet it's super crisp throttle wise around town, but that's not doing you any favors.
Click to expand...
And I thought I was being generous at 4500. I added an extra 500rpm because it has decent heads.
 
junkyardhero said:
it probably doesn't fall off a cliff straight away but plateaus till like 5, mayyybe 52 and then just stops making power.

the 650 is probably great for fuel mileage and i'd bet it's super crisp throttle wise around town, but that's not doing you any favors.
Click to expand...
I am sure you are right!
I haven't had a chance yet to switch between the two carbs to see if i noticed a difference. I am also considering buying the avs2 800 although that is not a double-pumper, and i believethe ratingsto be lower. My holley 750 has the old straight leg boosters which i heard doesn't play well with the air gap intake for fuel break up and distribution, but that could just be forum rumors.
Also, the reason for the summit carb was because it was based upon the autolight 4100, which is considered one of the best off road carburetors for incline angles and not uncovering the jets. I deal with a several steep inclines in Vermont
 
TT5.9mag said:
And I thought I was being generous at 4500. I added an extra 500rpm because it has decent heads.
Click to expand...
i think the exciting bit of the party is right there at 4 and change, and that bit from 45 to five is just a few drunk chicks dancing by themselves in the kitchen to a song that only they know till somebody pukes at 52 and is asked to leave.
 
4eighteener said:
I am sure you are right!
I haven't had a chance yet to switch between the two carbs to see if i noticed a difference. I am also considering buying the avs2 800 although that is not a double-pumper, and i believethe ratingsto be lower. My holley 750 has the old straight leg boosters which i heard doesn't play well with the air gap intake for fuel break up and distribution, but that could just be forum rumors.
Also, the reason for the summit carb was because it was based upon the autolight 4100, which is considered one of the best off road carburetors for incline angles and not uncovering the jets. I deal with a several steep inclines in Vermont
Click to expand...
woof, autofright. no thanks.

i'd go 3310 with some downlegs... or something more "modern" if i was shopping. the avs2 will be perfectly cromulent if you wanna party with carterbrock.

unless you're rock crawling i wouldn't really start to worry about inclines.

anyway, think about what you're using the truck for and that should help round the decision more clearly. for me when i hear: towing, some light off road trail work, and 3.23's with big ol tars i'm not thinking: double pumper.
 
I currently am running the Summit Autolight/Hollet knock off. They are a very good street carb with nothing wrong with it. IDK how they do for racing and other venues, but on the street, it works great. The jets are in the floor and would require a good bit of angle to uncover. Best part of the latest irritation of that carburetor is that it uses all holly parts.

The Carter/Edelbrock carbs are dry flowed for there cfm rating. I got with Charlie Servidio with a Edelbrock 600, it flowed 600. I also did some mods to it. After some work, we tested the 600 modded carb to a tune of 715 - IIRC. Choke removal, narrowing of the throttle blades, removing the extra bar across the secondary side for choke operation, booster narrowing and contouring. There is more to do with the carb above the air horn like a K&N stub stack and a bunch depends on the base of the air cleaner that you may have. Also the amount of air filter height (taller is better) and the lid, a K&N flow through lid is an excellent addition.

I also run a Edelbrock AVS 800 n a 340. No issue there. Though the AVS II would be a better choice with the annular boosters.

I can see better mileage from the annular booster as well as driving manners. I don’t see a lot though. Just a little. It’s all in the tune really.

I don’t know off hand but does the Weiand Action Plus/Stealth clear of the A/C compressor? Since big HP is not the goal with the set up, this intake has always worked very well for me in the past. The Steakth has the square carb pad, FWIW.

I’ve never seen a 1-3/4 header for the truck line. The mufflers are dyno max units which is really good. Among the best if not the best turbo chambered muffler on the market. The Summit turbo did very well on the Engine Masters cheap muffler test being the best all around and overall. I like them a lot.

There design is a direct rip from the old Sonic Turbos that was a DV design. Yep, David Vizard designed that a long time ago.
 
rumblefish360 said:
I don’t know off hand but does the Weiand Action Plus/Stealth clear of the A/C compressor? Since big HP is not the goal with the set up, this intake has always worked very well for me in the past. The Steakth has the square carb pad, FWIW.
Click to expand...
i don't think any of the aftermarkets have the offset t-stat besides the performer. and i know that the performer is the only one that's got the provisions to mount the compressor bracketry.

with an aftermarket bracket and the shorty compressor the weiand twins fit no problems.
 
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