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Discussion Starter · #1 · (Edited)
Hey Guys.
I have been pondering for months wether to use a cam I already have or to try something a little tamer. Engine is a 490 cube BBC. I have home ported factory iron 088 rectangle port heads.(GenV version of a 990 head) I have calculated the static compression at 10.3:1 with my chamber size and piston dome. I will be running an Offenhauser tunnel ram along with fender well headers. Car would be my 55' Gasser Wagon and should be about 3600 or so lbs. I have 4.56:1 axle gears with a 4speed as well. The cam I have is an Engle solid roller RJ83 with 304/304 deg adv. duration 264/264 deg. 0.050 duration and 670"/670" lift with a 110 Deg Lobe centre. The Engle description is pretty vague " Street/Strip, Bracket racing, large circle track, heavy jet boat racing. Powerband 3200-6500 RPM" I have talked to Engle and they said it would be on the far end of street able but could work. They can do a smaller regrind for $120 but I am on a tight budget and I would have to drop down south of the border to ship away and get done. Also our Canadian buck sucks right now. I am sure it would end up being about $220 with shipping and our dollar exchange. This car will be for street and strip but I don't expect it is going to be a comfortable cruiser. I have my 66 Skylark GS for that. I want a serious rowdy and loud big block I can drive on the street to scare people. I bought this cam used with less than 200 miles on it. The previous owner had it in a 69 Camaro street/strip car with a similar engine but 11.5:1 compression. He said it was totally drivable on the street. He only swapped it out as he was doing a complete pro touring overhaul of the car and was planning some long road trip driving. My father in-law says I should just stab it in and see what I end up with. It seems to me it should be street drivable. I was always told from my Dad and his hot rodding buddies that when picking a cam you go through the catalog and pick the cam description that seems closest to what you think you want then choose the next smaller one. In this case going from the catalog I would want the cam just smaller than this one. It is not like this will be a daily driver so even if I don't like it I figure I could pull it back out and do a regrind later. Just wondering what all you opinions might be so I can make a decision on which way to go. Thanks.
Greg
 

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My answer would be based on what transmission and rear gear ratio you'll be running. If your car has an automatic, or gear ratio of 3.73 or taller, then I'd say not to use it. If it's a stick, and has 3.90 or lower gears, then I'd give it a try. That cam will be tough to use on the street without a very high stall converter in an automatic, and very low gear ratio. Wont be much fun, even with the right ratio, and converter running an automatic.
 

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Personally, I'd say run it. I have always been a bottom of the page cam type of person though, so take that for what its worth.

If the plan is to have a mean and nasty big block to cruise the streets with and you'll be avoiding highways and long cruises, I think it would be fine. The minute you want to take that car on a long road trip, it won't be as enjoyable (ask me how I know). But a local stoplight-to-stoplight car, local car shows, and weekend racer if you want it, it'll be a fun car. Go for it. If you hate it, you can always save the money and swap it later.
 

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Unless its a roller I would not run it, you will be adding a second wear pattern, and it may fail in short order, the first break in is critical, then with a different block and lifters you will be repeating the process, adding a second pattern to the cam lobes,witch may work out, may not, just as you always put a used lifter back in on the same cam lobe when doing repairs, just think if it fails all that hardened metal goes threw your engine, plus you don't sound like your sure that its the cam you want for a street ride, plus what Vall says you can do it with the 4 speed your running but an auto trans is a whole new can of worms....... Also cams don't scare people 6-71 Blowers scare people
 

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Discussion Starter · #5 ·
My answer would be based on what transmission and rear gear ratio you'll be running. If your car has an automatic, or gear ratio of 3.73 or taller, then I'd say not to use it. If it's a stick, and has 3.90 or lower gears, then I'd give it a try. That cam will be tough to use on the street without a very high stall converter in an automatic, and very low gear ratio. Wont be much fun, even with the right ratio, and converter running an automatic.
The car will be a top loader 4 speed and 4.56:1 rear gear with 29" tires. That should be sufficiently low gearing to pull through quickly. I agree, I would not consider this cam for an auto in street use at all. With a steep rear gear and big stall converter it would be possible to use at the strip but would be completely useless on the street.

Road Angels
Unless its a roller I would not run it, you will be adding a second wear pattern, and it may fail in short order, the first break in is critical, then with a different block and lifters you will be repeating the process, adding a second pattern to the cam lobes,witch may work out, may not, just as you always put a used lifter back in on the same cam lobe when doing repairs, just think if it fails all that hardened metal goes threw your engine, plus you don't sound like your sure that its the cam you want for a street ride, plus what Vall says you can do it with the 4 speed your running but an auto trans is a whole new can of worms....... Also cams don't scare people 6-71 Blowers scare people
It is stated in my original post that the cam is a solid roller. I agree, I would be extremely reluctant to re-use a flat tappet cam for those same reasons. I have reused roller cams before with no issues. Thanks for the input guys. I am trying to keep this relevant to my application, with consideration to what are my current planned components. I have listed most details in the original post. I also agree 6-71 blowers make a great impression but that it will be out of my price range. This motor should be sufficiently radical for my intended application.

Greg
 

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My bad I only remembered the solid part of the cam info when I read the post thinking flat tappet, listen to your Dad's advice it's solid no pun intended, yea blowers are bucks but being speed freak my self the only thing that makes the hair stand up is the sound and feel of the 68 camaro with a big block that every once in a while, will pull up next to me at a light when I am in town, I can feel him coming
 

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Sounds like a great cam for the 4 speed and 4.56 gears. A roller cam is no problem at all. Even using used roller lifters, with a new cam, or vice versa, is fine. I've never built an engine with a roller cam, but my next build, or next cam I'm going to give one a try.
 

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It sure saves the headache of worrying about the flat tappet break in, with having to add zinc and other stuff to your oil, and keeping the revs high at first start up and break in
 

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Discussion Starter · #9 ·
It sure saves the headache of worrying about the flat tappet break in, with having to add zinc and other stuff to your oil, and keeping the revs high at first start up and break in
Yes it is nice not to have to worry of the whole cam break in deal. No break in valve springs or additives to deal with either.
 

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Discussion Starter · #11 ·
Post a video of the engine running when you get to that point. I want to hear it run...
I will sure try to get a video posted. Might be some time though. I have years of work to get done yet. I have been collecting stuff to build an engine run stand though. I may just put that together and do the first runs and tuning on the engine run stand. I always wanted a run stand to fire my stuff up on once in a while.
Greg
 

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Discussion Starter · #12 ·
Do you guys think it will be tough to get the carbs to idle well with my offenhauser tunnel ram and edelbrock carbs? I do not have power brakes in the plan so I am not concerned with low vacuum running this cam. I am concerned it may be a little tough to have good carb signal for idle and low speed. I do have a tuning kit and I have found the edelbrock/carter carbs are pretty easy to tune in the past. I was hoping the split plenum in the offenhauser "turbo thrust 360 power port" tunnel ram would help with the idle and low speed operation.
 

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I will sure try to get a video posted. Might be some time though. I have years of work to get done yet. I have been collecting stuff to build an engine run stand though. I may just put that together and do the first runs and tuning on the engine run stand. I always wanted a run stand to fire my stuff up on once in a while.
Greg
The real world doesn't run at the speed of the internet... take your time and enjoy the build. We'll still be around waiting to hear it run when it's ready.

I have no experience with getting the engine to idle with a tunnel ram, but I assume it can be done as lots of people have run them. Your idle just might be a little high, 1000 rpm or so.
 
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