Re: Cam Recommendation - 340
[Re: dd340]
#2264936
03/07/17 03:36 PM
03/07/17 03:36 PM
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Joined: Jan 2003
Posts: 16,376
dogdays
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,376
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More's Law:
If some is good, More's better, and Too much is just right.
You seem to be following that to the letter. Back up, pilgrim! Before anyone can make a cam selection there needs to be some information shared. Such as, Real compression ratio Rear gear ratio Converter stall speed, or 4-speed Intake Carb Exhaust Intended use for the car
Hughes Engines has five camshafts between 220 and 232 intake duration at 50 lift. The 220 cam has 0.503 lift compared to your 0.460 lift. It is possible that that cam would make more power than your cam with the same valve opening and closing points, simply because it gets the valve open quicker, longer. I know this board loves Racer Brown, but he sold you a Chevy lobe. It does have one advantage, it is easier on the valvetrain because of its lazy lifter acceleration rates.
If you're going for a Comp 274, you get more from the XE275HL. Or comparable Lunati or Hughes cam.
But first what are the answers to the questions above?
R.
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Re: Cam Recommendation - 340
[Re: dd340]
#2264944
03/07/17 03:50 PM
03/07/17 03:50 PM
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Joined: Jan 2003
Posts: 5,444 Indiana
YO7_A66
master
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master
Joined: Jan 2003
Posts: 5,444
Indiana
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""Any other recommendations for a cam in this range?""
I would suggest emailing Scott Brown with your information. He designed my 226/238 (1.5 =.489"/.480" lifts) cam for my 340.
scotty.brown@ymail.com
1970 YO7 A66 [Canadian Export] F8 Challenger 340 (Currently in shop for stroker assy.)
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Re: Cam Recommendation - 340
[Re: dd340]
#2264970
03/07/17 04:33 PM
03/07/17 04:33 PM
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Joined: Sep 2014
Posts: 4,457 Washington
madscientist
master
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master
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Washington
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Jim already did you right once. Why not use him. It will be worth the wait.
Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
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Re: Cam Recommendation - 340
[Re: crackedback]
#2265010
03/07/17 05:39 PM
03/07/17 05:39 PM
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Joined: Jan 2003
Posts: 727 Ottawa, ontario
dd340
OP
super stock
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OP
super stock
Joined: Jan 2003
Posts: 727
Ottawa, ontario
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If you have stock rockers, they are going to be another limiting factor. Start getting much over the .500 lift point and stamped pieces don't like the increased spring pressures. I am using stock rockers and plan on keeping them. I am looking for reliability and ease of use as much as a bump up in power.
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Re: Cam Recommendation - 340
[Re: dogdays]
#2265012
03/07/17 05:41 PM
03/07/17 05:41 PM
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Joined: Jan 2003
Posts: 727 Ottawa, ontario
dd340
OP
super stock
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OP
super stock
Joined: Jan 2003
Posts: 727
Ottawa, ontario
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More's Law:
If some is good, More's better, and Too much is just right.
You seem to be following that to the letter. Back up, pilgrim! Before anyone can make a cam selection there needs to be some information shared. Such as, Real compression ratio Rear gear ratio Converter stall speed, or 4-speed Intake Carb Exhaust Intended use for the car
Hughes Engines has five camshafts between 220 and 232 intake duration at 50 lift. The 220 cam has 0.503 lift compared to your 0.460 lift. It is possible that that cam would make more power than your cam with the same valve opening and closing points, simply because it gets the valve open quicker, longer. I know this board loves Racer Brown, but he sold you a Chevy lobe. It does have one advantage, it is easier on the valvetrain because of its lazy lifter acceleration rates.
If you're going for a Comp 274, you get more from the XE275HL. Or comparable Lunati or Hughes cam.
But first what are the answers to the questions above?
R. I guess my question to this is, do the faster ramps that are quite popular now really show significant power bumps? I would be curious to hear any first hand feedback.
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Re: Cam Recommendation - 340
[Re: dd340]
#2265175
03/07/17 10:19 PM
03/07/17 10:19 PM
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Joined: Jan 2003
Posts: 16,376
dogdays
I Live Here
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I Live Here
Joined: Jan 2003
Posts: 16,376
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http://www.hotrod.com/articles/mopp-0201-cam-velocity-advantage-mopar/This article is 15 years old. Hughes has an even hotter lobe set now. For me, the ability to make the same power with a 10 degree smaller cam is very attractive. I like driveability. Have you answered the questions yet? If not, we're still barking at the moon. R.
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Re: Cam Recommendation - 340
[Re: dogdays]
#2265182
03/07/17 10:31 PM
03/07/17 10:31 PM
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Joined: Jan 2003
Posts: 727 Ottawa, ontario
dd340
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super stock
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OP
super stock
Joined: Jan 2003
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Ottawa, ontario
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Thanks for the link, I will look it over. If you look at my original post I answered the questions that you had asked.
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Re: Cam Recommendation - 340
[Re: forphorty]
#2265183
03/07/17 10:33 PM
03/07/17 10:33 PM
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Joined: Jan 2003
Posts: 727 Ottawa, ontario
dd340
OP
super stock
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OP
super stock
Joined: Jan 2003
Posts: 727
Ottawa, ontario
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I think with your lack of stall and gear, you might be better off sticking with the cam you have. Going much hotter than what you have risks taking as much from the bottom as it adds to the top. To me, the 274 XE sounds a little big for a 340 with 2500 stall. Now, if you were to put a looser converter in.... Also, some of the high velocity/ high rate of lift cams would make me a little nervous with the stock rockers. Have you had this car on the track? How does it run? My best time at the track is 13.7 @ 102 with my current set up. It has a pretty poor 60 ft time so I think it could be better for sure.
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Re: Cam Recommendation - 340
[Re: dd340]
#2265470
03/08/17 10:31 AM
03/08/17 10:31 AM
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Joined: Feb 2005
Posts: 4,319 Prospect, PA
BSB67
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Prospect, PA
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Now that you posted your et/mph, most responses will now be about 60ft times and converter, gear and tires. So, the question to you is: Is it about et for you, or about making more power (i.e. et and mph)? It is a personal choice. Personally, I prefer making more power. In your case, this would have an end result of 13.2 @ 106 mph, verses 13.2 @ 102 mph, as an example. So if it is power you seek, I think you are probably going down the right path. I think it might be helpful for the smart cam guys on here to know what your current cranking cylinder pressure is. Finally, I would recommend a small solid cam, but you will need adjustable rockers. I think there is an undesirable risk with a fast rate hydraulic for you as the valve train seems to start giving it up too early, especially for a small block. And the slower ramp cams will cause a noticeable deterioration of the low speed characteristics of your small block. A solid flat tappet is the best of both worlds.
Last edited by BSB67; 03/08/17 10:45 AM.
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Re: Cam Recommendation - 340
[Re: BSB67]
#2265545
03/08/17 01:30 PM
03/08/17 01:30 PM
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Joined: Jan 2003
Posts: 727 Ottawa, ontario
dd340
OP
super stock
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OP
super stock
Joined: Jan 2003
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Ottawa, ontario
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Now that you posted your et/mph, most responses will now be about 60ft times and converter, gear and tires. So, the question to you is: Is it about et for you, or about making more power (i.e. et and mph)? It is a personal choice. Personally, I prefer making more power. In your case, this would have an end result of 13.2 @ 106 mph, verses 13.2 @ 102 mph, as an example. So if it is power you seek, I think you are probably going down the right path. I think it might be helpful for the smart cam guys on here to know what your current cranking cylinder pressure is. Finally, I would recommend a small solid cam, but you will need adjustable rockers. I think there is an undesirable risk with a fast rate hydraulic for you as the valve train seems to start giving it up too early, especially for a small block. And the slower ramp cams will cause a noticeable deterioration of the low speed characteristics of your small block. A solid flat tappet is the best of both worlds. Thanks for bringing that up. I considered reposting to get the focus back on making more power. My main goal was to add some more mid to high rpm power, not necessarily to maximize my ET. I am only on the track a vary rare occasions so that is not my top priority. I am not sure what my cranking pressure is but I know it must be pretty high because it will have significant knock on 91 octane but using 94 seems to correct that. I have a feeling a little more cam would bleed off a little cylinder pressure as well. Are there any decently priced adjustable rockers available if I went with a solid cam?
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Re: Cam Recommendation - 340
[Re: dd340]
#2265779
03/08/17 08:33 PM
03/08/17 08:33 PM
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Joined: Feb 2005
Posts: 4,319 Prospect, PA
BSB67
master
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master
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Posts: 4,319
Prospect, PA
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Are there any decently priced adjustable rockers available if I went with a solid cam?
I don't know what decent price means to you. In my opinion, low cost adjustable rockers are an unacceptable risk. And I think that most people would say that a good (not great) rocker is not inexpensive.
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