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Old 12-13-2016, 11:48 AM
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Need help in cam selection

Ok so I'm not very familiar with lift and all that detailed stuff. I love working on motors but I just barely did my first 350 swap so I'm still very new to this. I want to beef up my 350 a little, it has 991 heads, rpm air gap intake, holly 4175 650 cfm electric choke carb. I wanted to know if this is a good kit that I found on Amazon and if my heads will work with it.
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Old 12-13-2016, 12:52 PM
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That appears to be a good camsfaft and matching components. It will be good for a 3,700 - 3,900 lb car with a stock automatic transmission and 3.08 rear gears. The compression ratio should be held from 9.0:1 to 9.5:1.

All you need is a tachometer. The peak torque of the engine should be at 3,200 - 3,600 RPM with 5,000 RPM shift points with a 4-speed and 3.36 rear gears.

Last edited by MouseFink; 12-13-2016 at 01:05 PM.
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Old 12-13-2016, 04:01 PM
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Ok so I have it in my 77 Chevy with the 700R4 tranny np 208 transfer case and stock rear 12 bolt and stock 10 bolt front. I think the truck is around 4000 to 4500 pounds. Would this still be a good investment? Even with the 991 heads? And it won't cause any problems with these heads right?
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Old 12-13-2016, 04:41 PM
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That is a very mild cam. The duration #'s listed are most likely advertised and not @ .050" lift. What I would consider an RV cam. What you would really want to know is the duration #'s at .050" lift, and the LSA or lobe separation angle. The LSA will determine where the power is made more so than actual lift. I would guess that cam is going to fall in the 200-215 (or less) duration at .050", and may have an LSA from as low as 112 all the way up to 119.

It is a perfect cam for a 4x4 vehicle used for off-road use, or light towing.
I ran that exact cam in a '69 Camaro with a 6 speed manual trans and it barely had any lope, or rumble, to it.

Keep in mind those lift #'s are LESS THAN a factory hydraulic roller cam in a 4.8L engine. Very mild.

You are wanting to know if that is a good cam.. It would be better if you knew exactly what you wanted out of the motor, and then you add the parts necessary to get there. If you want some lope to it-NO, that is not a good cam. If you want torque right off idle all the way up to 5500-you found just what you need. The only thing I would comment on is that your RPM Air Gap is stealing some of your low end torque. You would have been better off just staying with a smaller intake, or something less high RPM oriented such as a regular Edelbrock Performer, or Weiand. That cam and that intake will work together, but it is not optimal. With that cam, I would recommend a smaller intake. Or, since you already have the RPM, you could step up to a bigger cam... a bigger cam will make more HP up top, but at the expense of a loss of torque/hp right off idle. So, smart money would be that cam with a smaller intake and you should have a torque motor with the trade off being that you won't have a high rpm screamer. The intake you have now will just start to come into where it works best/makes the most power, right as that cam starts to sign off.

Here is some reading on intakes if you have time. Dual Plane Intake Manifold Comparisons - Hot Rod Network

Please keep in mind that this is just my opinion and that there are many smarter folks who post here who may offer a different opinion.
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Old 12-13-2016, 07:11 PM
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So would this one be better? For all around performance?
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Old 12-13-2016, 07:22 PM
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Do you know the manufacturer of these cam kits? I'm asking because the add doesn't give any information about the cam profile. I think these are off shore cams and they may not be made of the best materials. When the lifters and lobes go flat who do you call?
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Old 12-13-2016, 07:27 PM
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It says it's from a business called Engine Parts Center they have 97% positive feedback in their lifetime.
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Old 12-13-2016, 08:13 PM
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Disagree with Transmech. Edelbrock Performer RPM will make more power under curve from 1500 to 6000 than any other intake manifold you could bolt onto the motor. Frieburger has proved this on the dyno. I do not like the Air Gap because I have had reports of drivability problems in cooler weather. The intake charge of fuel and air needs the warmth of the motor in the intake manifold to help break down the air/fuel mixture into a fog that is ignitable in the motor. If big clumps of fuel make their way into the motor through a cold manifold, they cannot be burned and the motor will lurch and buck (drivability problems). Use only the regular Performer RPM or the Weiand 8150 on a street motor. Now, if you want to use an Air Gap at the drag strip, knock yourself out, but don't use one on the street.

Agree with OldTech. Never buy cam or cam parts from anyone but the cam grinders themselves. The cam and associated parts are the most stressed parts in the motor and you must guarantee that you are installing ONLY THE HIGHEST QUALITY PARTS. I like Howards, Iskenderian, Lunati, Crane, Crower. Further, I do not recommend using a flat tappet cam anymore. The oil manufacturers have removed the Extreme Pressure lubes that they used to use in the oil and it's a coin toss as the whether or not the cam will survive. Please read through this tutorial that I wrote several years ago concerning the steps to take to try and make a flat tappet cam survive in today's world.
http://www.crankshaftcoalition.com/w...ips_and_tricks
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Old 12-13-2016, 08:20 PM
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need help in cam selection

I would use this camshaft with a set of these Aluminum heads. https://www.summitracing.com/parts/p...make/chevrolet https://www.summitracing.com/parts/h...make/chevrolet https://www.summitracing.com/parts/hup-gm25hd/overview/ I hope you have flat top pistons with a deck height of .025. You will need this Vortec intake manifold. https://www.summitracing.com/parts/edl-7116/overview/ This is the camshaft I would run in my truck. https://www.summitracing.com/parts/h...make/chevrolet Use them 991 heads for boat anchors!

Last edited by camarodriver67; 12-13-2016 at 08:33 PM.
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Old 12-13-2016, 11:02 PM
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whats inside your engine? Why do you want a new camshaft? Your intake is ok, the heads are nothing special in any way. Do you have a good exhaust system? Camshaft is near the bottom of the list to buy without other good parts to support its efforts,,,
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Old 12-14-2016, 08:50 AM
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The motor is stock with dished Pistons I think. It has headers with a 3 inch exhaust. What should I look to buy first then? Heads and like flat top Pistons? These are the heads I'm looking at getting for it. Are they a good choice?
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Old 12-14-2016, 09:27 AM
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I ran the edelbrock rpm air gap intake on my previous build and trust me techinspector1 knows his stuff as he has helped me many times over with issues in the past and still does. The weiand 8150 or edelbrock rpm intakes are really good intakes and also the summit brand name high rise intake is actually the weiand 8150 high rise intake but just with the summit name on it as I have gotten one before for someone and noticed the 8150 number casted into it. You will get better results with it over the air gap.
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Old 12-14-2016, 10:07 AM
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Quote:
Originally Posted by 77chevyk10 View Post
The motor is stock with dished Pistons I think. It has headers with a 3 inch exhaust. What should I look to buy first then? Heads and like flat top Pistons? These are the heads I'm looking at getting for it. Are they a good choice?
Since you are buying the heads bare, here is a better deal. Same or better quality head, a couple hundred dollars cheaper. $400/pair rather than $300/each for the Flo-Teks
SBC Small Block Chevy Straight Plug Aluminum Cylinder Head Set 64cc 2.02/1.60 | eBay

This is the ProHeader import casting, also used by Assault Racing and a few others. It's a copy of the Dart Pro-1 Platinum Series 200cc,.... you may decide that is a bit too much runner volume for your needs but I thought I'd at least give you the option.

I have no idea whose import casting Flo-Tek is using, nobody seems to know for sure.
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Old 12-14-2016, 01:19 PM
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Quote:
Originally Posted by ericnova72 View Post
Quote:
Originally Posted by 77chevyk10 View Post
The motor is stock with dished Pistons I think. It has headers with a 3 inch exhaust. What should I look to buy first then? Heads and like flat top Pistons? These are the heads I'm looking at getting for it. Are they a good choice?
Since you are buying the heads bare, here is a better deal. Same or better quality head, a couple hundred dollars cheaper. $400/pair rather than $300/each for the Flo-Teks
SBC Small Block Chevy Straight Plug Aluminum Cylinder Head Set 64cc 2.02/1.60 | eBay

This is the ProHeader import casting, also used by Assault Racing and a few others. It's a copy of the Dart Pro-1 Platinum Series 200cc,.... you may decide that is a bit too much runner volume for your needs but I thought I'd at least give you the option.

I have no idea whose import casting Flo-Tek is using, nobody seems to know for sure.
I just read that no one knows where these come from. Any info on these would be good. Like a company name? Experiences eith them? The price is appealing but I live by the motto you get what you pay for.
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Old 12-14-2016, 02:28 PM
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I do believe they are procomp heads which has a reputation to be good for some and have no issues and some other people have had nothing but problems with the quality of the castings but you would want them bare so you can get some good quality parts.
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