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Re: Cam Experts
[Re: Sb Valiant]
#1635805
06/19/14 11:16 PM
06/19/14 11:16 PM
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Joined: Dec 2013
Posts: 403
Romulus, MI
GTS340
mopar
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mopar
Joined: Dec 2013
Posts: 403
Romulus, MI
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Small displacement engines are easy to over cam because they make camshafts behave like they are bigger (duration) than they are. On your 344 I personally wouldn't go over 264@050 (and that is if you are indeed 13:1 static CR) but I'm sure others will recommend otherwise. As far as lift, having your heads tested on a flow bench will be a valuable tool, it will also help spec how fast of a rate of lift. Best bet would be to call someone like Bullet cams with all your accurate specs and they will help you out.
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Re: Cam Experts
[Re: Sb Valiant]
#1635806
06/19/14 11:18 PM
06/19/14 11:18 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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I dont think you will get the bulk of the guys on here to agree on anything... but with a large duration cam you loose some of the bottom end due to when the intake closes... also we need to know a bit more.. is it a foot brake car or trans brake... most guys with a TB dont ever see any low rpm and then a larger duration can be a little better.. but if you start low in the rpm then the smaller duration is helpful... but other things will come into play also.. the LSA and the installed degrees and the lift is more based on the head flow 
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Re: Cam Experts
[Re: Sb Valiant]
#1635809
06/19/14 11:36 PM
06/19/14 11:36 PM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Trans brake all the way Mr P. I'll be making a move to the right converter here soon. 8" between 5000-5500 stall. I would like to get the heads and intake manifold on a flow bench before anything goes together and picked out.
When using a high flow head.. I should say large cross
section area you have to turn more rpms to make the
heads efficient and when you turn up the rpm you have
to gain lift or duration to fill the cyl in the short
time you have in the upper rpm.. so yes you should
know all the data on the heads first thing
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Re: Cam Experts
[Re: Thumperdart]
#1635811
06/20/14 12:03 AM
06/20/14 12:03 AM
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Joined: Jan 2003
Posts: 11,711
Portage,michigan
B3422W5
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 11,711
Portage,michigan
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If your looking for cam help for a combination I can give three words of advice....call Dwayne Porter........
69 Dart GTS A4 Silver All steel, flat factory hood, 3360race weight
418 BPE factory replacement headed stroker, 565 lift solid cam
Best so far, 10.40 @127 1/4
1.41 best 60 foot
6.60 at 103.90 1/8
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Re: Cam Experts
[Re: Thumperdart]
#1635812
06/20/14 12:17 AM
06/20/14 12:17 AM
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Joined: Oct 2009
Posts: 1,267
North, Alabama
D-50
pro stock
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pro stock
Joined: Oct 2009
Posts: 1,267
North, Alabama
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My small block is 394ci. which is larger than yours, that would probably make a difference. But roller cam is 255/266 @ .050, 10.9 to 1 comp. Mine has pretty good bottom end 1.33 60ft. and I have ran 109 mph in the 1/8. I Believe if I had more duration at .050 I would not have a lot of cranking cylinder pressure. But I can run pump gas. It is 190-200 now.
1.33 60 ft,6.21 at 110.59 in the 1/8, pump gas small block,2950lbs,drag radials,mufflers and driven to track ...
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Re: Cam Experts
[Re: D-50]
#1635813
06/20/14 12:37 AM
06/20/14 12:37 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Smaller stroke engines need less duration... as the stroke goes up so should the duration... but the thing is... what is the amount... yeah it can be figure in math but a good cam person that knows all the specs of the engine will have a better handle on it plus he most likely has other engines out there with known power and results
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Re: Cam Experts
[Re: Dunnuck Racing]
#1635815
06/20/14 02:07 AM
06/20/14 02:07 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
I'll also mention this, when bad advice gets repeated enough on a forum, many people treat it as gospel.
You sometimes have to learn by trial and error, either who to take advice from, or by trying things for yourself
Keith
Yeah I went with the advise of a so called cam guy
and its way off ... mine could use at least .100-
.150 more lift and the duration is to much... he knew
the engine specs and head flows and came up with what
I have... I thought about having it reground but I
ended up selling the engine and I gave the buyer a
new cam core to have another cam ground or he can
have the one in it ground and keep the core as a spare
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Re: Cam Experts
[Re: Sb Valiant]
#1635816
06/20/14 02:12 AM
06/20/14 02:12 AM
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Joined: Jan 2003
Posts: 5,485
SoCal
Brian Hafliger
master
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master
Joined: Jan 2003
Posts: 5,485
SoCal
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Quote:
Hello moparts maybe you can help me understand more about .050 cam duration specs. I've talked to several cam manufacturers and people who know cams
supposely. How is it that guys are able to run 252° duration and run deep into 10's? How do you make enough low and top end power in a smaller ci with that conservitive amount of duration. I've heard people suggest 252-258° and 've heard 272-276 @ .050. Also some say between 520-550 lift and some say 620-660 lift. It just doesn't make any sence to me. Either of the cam specs seem to run good under most engine combos. Either 1 guy is shifting at 6000 or the other is 7500. But then I hear people shifting these low duration cams high? My combo is a 344 ci with W2 heads ported, 2.08" intake valves. M1 intake manifold with a lot of work, between 12:1/13:1 cr, 1 7/8 headers, 850 e85 holley carb, and I am wondering what the right cam choice is for this setup. Attended goal is mid 10's.. I'd just like to know something that multiple would agree on so it's not like well 5 guys have this and that opinion and the other 5 have the same opinion. Thanks Moparts
The biggest difference you need to look at is what TYPE of cam...Solid roller, solid FT, hyd. FT, or Hyd. roller. Duration @ .050 is just a point on the lobe the lifter hits...and the shape of the "curve" will look very different between all these cam types.
My 360 in my duster ran 10.50's and 10.60's with a solid FT cam that was 264@ .050 and made peak HP at 7300 on my dyno. It also had W2 heads. Before that, I had a solid FT cam that was 250-258@ .050 and peaked at 7100rpm.
You have to take everything about the car/engine and intended usage into consideration when spec'ing a cam IMO. It also doesn't hurt to have experience.
Brian
Brian Hafliger
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Re: Cam Experts
[Re: B3422W5]
#1635817
06/20/14 02:35 AM
06/20/14 02:35 AM
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Joined: Jan 2003
Posts: 27,421
Balt. Md
383man
Too Many Posts
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Too Many Posts
Joined: Jan 2003
Posts: 27,421
Balt. Md
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Quote:
If your looking for cam help for a combination I can give three words of advice....call Dwayne Porter........
This is very good advise.  Dwayne speced my solid flat tappet for my 63 street car and I am very happy with it. I have been a tech for about 40 years (will be 58 in July) and I became a tech because I wanted to build my own engines and cars so I made myself learn as much as I could because I wanted to know how every part of a car worked and I learnt alot about cams and feel I know cams pretty good. But when it comes to specing the right cam for a certain build its best to go with someone who is really a pro at that and does it everyday and then dyno's the engines so they know what works best because they are a pro at that and do it every day. Thats what Dwayne Porter is a pro at eng builds including specing cams. Many of us gearheads on hear know cams pretty good but as Mr P said you will still get 20 different answers as most of us know how cams work but dont match them to eng builds everyday. Myself I will tell you to call Dwayne Porter and talk to him as every eng I see he does work on always runs good. Thats one of the reasons I went to him. If you decide too we have his phone # so just ask if you want it. I will say on a side note that one thing I found is I would rather under cam then over cam an eng. Ron
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Re: Cam Experts
[Re: Brian Hafliger]
#1635818
06/20/14 03:32 AM
06/20/14 03:32 AM
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Joined: Nov 2012
Posts: 358
western PA
Sb Valiant
OP
enthusiast
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OP
enthusiast
Joined: Nov 2012
Posts: 358
western PA
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Well here is where I am at. I bought a slightly used solid roller cam off a guy I know on Facebook. He was running it in a 416 ci 14:1 cr with W2 heads and claimed he needed more cam for his combination. With the little knowledge I have I thought the cam specs were pretty reasonable for my build. It's a custom grind Reed cams 625/625 @ 1.5 with 260/265 @ .050, 294/300, on a 106 centerline. I got the cam plus shipping for $155. Thinking I was saving money and getting a good deal the solid roller setup is still expensive.. I still need roller lifters, valve springs, and "should" buy all new valves and retainers, plus bronze distributor gear, ect. I have a set of bushed iron rockers that have had a good amount of runs over the years on them how many I don't know  . I've heard I can run a roller cam on them but it would be much better if I could find a set of roller rockers and I posted a wanted ad. With out looking @ the cam card I know the cam calls for over 600 lbs open spring pressure and I need a decent rocker to use the cam w/o any issues. If worst came to worse I could always throw a solid FT in and it would be much more forgiving on parts. Either way I am trying to work with anything I can here.. I'm trying to for fill my goal of tbeing in the 10's. How far in the 10's? I really don't know it could be a 10.99 or 10.29 I could live with either one. It would be nice to go deep as possible into the 10's with what I have to work with. For a rpm I don't want to get too carried away but I can live with 7,500 rpms. I don't want to go much more or any over that. The car is lite and it should work good with the new ladder bar and coil over setup. Thanks
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Re: Cam Experts
[Re: Sb Valiant]
#1635819
06/20/14 05:42 AM
06/20/14 05:42 AM
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Joined: May 2008
Posts: 5,399
Aurora, Colorado
451Mopar
master
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master
Joined: May 2008
Posts: 5,399
Aurora, Colorado
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Call the experts and see what they recommend. You will need an idea of what the heads flow, and the intake port cross section area (no reason to over cam what the heads won't flow.)
If the car is setup with alot of gear and converter, you can use a larger cam that has more power in a narrow power band. If the car is more street/strip setup, then you need a wider power band / smaller cam. The 0.050" numbers are just a general reference point when comparing cam size, but it tells nothing of the rate of lift (two cams with the same 0.050" numbers can be quite different at 0.200+" lobe lift.) Your rocker arm ratio needs to be taken into account too. For our older Mopar engines, usually 1.6:1 ratio is normal, higher ratios are fairly uncommon because of cost.
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Re: Cam Experts
[Re: Sb Valiant]
#1635820
06/20/14 10:40 AM
06/20/14 10:40 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Well here is where I am at. I bought a slightly used solid roller cam off a guy I know on Facebook. He was running it in a 416 ci 14:1 cr with W2 heads and claimed he needed more cam for his combination. With the little knowledge I have I thought the cam specs were pretty reasonable for my build. It's a custom grind Reed cams 625/625 @ 1.5 with 260/265 @ .050, 294/300, on a 106 centerline. I got the cam plus
shipping for $155. Thinking I was saving money and getting a good deal the solid roller setup is still expensive.. I still need roller lifters, valve springs, and "should" buy all new valves and retainers, plus bronze distributor gear, ect. I have a set of bushed iron rockers that have had a good amount of runs over the years on them how many I don't know . I've heard I can run a roller cam on them but it would be much better if I could find a set of roller rockers and I posted a wanted ad. With out looking @ the cam card I know the cam calls for over 600 lbs open spring pressure and I need a decent rocker to use the cam w/o any issues. If worst came to worse I could always throw a solid FT in and it would be much more forgiving on parts. Either way I am trying to work with anything I can here.. I'm trying to for fill my goal of
tbeing in the 10's. How far in the 10's? I really don't know it could be a 10.99 or 10.29
I could live with either one. It would be nice to go deep as possible into the 10's
with what I have to work with. For a rpm I don't want to get too carried away but I can live with 7,500 rpms. I don't want to go much more or any over that. The car is lite and it should work good with the new ladder bar and coil over setup. Thanks
I have a cam similar to your roller in my 416 in
my Rampage.. it seems to work pretty decent.. granted
mine is similar but yet its different.. mine has .015
more lift and is on a 105 LSA.. I normally install
a cam advanced to help the lower rpm torque but on this
one I put it in a 105 because I didnt want the added
torque to stall the conv higher being its a 5000 stall
already and its a street/strip car
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Re: Cam Experts
[Re: Dunnuck Racing]
#1635822
06/20/14 11:08 AM
06/20/14 11:08 AM
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Joined: Jun 2003
Posts: 52,972
Romeo MI
MR_P_BODY
Master
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Master
Joined: Jun 2003
Posts: 52,972
Romeo MI
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Quote:
Since we are talking camshafts and rocker arms I'll throw this in.
Look at how many guys tell you a 1.6 rocker ratio is good on the intake side but not on the exhaust side. Then they will recommend a camshaft with a huge duration and/ or lift split favoring the exhaust side. Every "expert" has their own way of doing things and not necessarily the best way.
Keith
I am no expert on cams thats for sure... I have plenty
of trial and error time in on my own junk
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Re: Cam Experts
[Re: Dunnuck Racing]
#1635823
06/20/14 12:30 PM
06/20/14 12:30 PM
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Joined: Nov 2004
Posts: 3,544
Syracuse,NY
CompWedgeEngines
master
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master
Joined: Nov 2004
Posts: 3,544
Syracuse,NY
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Quote:
I'll also mention this, when bad advice gets repeated enough on a forum, many people treat it as gospel.
You sometimes have to learn by trial and error, either who to take advice from, or by trying things for yourself
Keith
Hallelujah on that one Keith!...
RIP Monte Smith
Your work is a reflection of yourself, autograph it with quality.
WD for Diamond Pistons,Sidewinder cylinder heads, Wiseco, K1 rods and cranks,BAM lifters, Morel lifters, Molnar Technologies, Harland Sharp, Pro Gear, Cometic, King Engine Bearings and many others.
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