Design a custom cam for me thread
#41
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Been talking with a guy about playing with idle timing advance/retard to give the smaller cams that big cam sound. I'd look into this first before changing a cam for sound.
#43
Speedtigger - I have an EPS 226/230 on 113 LSA (2* overlap). When you said something in an earlier post about an in-between cam that would neither lope steady or idle steady, that's what I think about the cam I have. I'm anxious to hear if an additional -2* LSA (4* overlap) will lope like you want it to, since it sounds like we have the same requirements. When I initially talked to Geoff about the cam specs he recommended 226/234-113 but we ended up with a more conservative route - 226/230 (I wanted to err on the conservative side). I've read many times you can live with 5-7* overlap for a DD/street car and that's definitely what I'll be shooting for next time. My biggest question is - should you get more overlap by decreasing LSA (the direction you're heading) or increasing exhaust duration like Geoff suggested? Interesting discussion.
How is the power on that cam?
#44
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Don't fix it if it ain't broken.
Play with the idle and perhaps cutouts for when you want too feel more macho.
Nice ride, I just got a 64 vert Implala, last week, I'll be droping a 402 in there.
Play with the idle and perhaps cutouts for when you want too feel more macho.
Nice ride, I just got a 64 vert Implala, last week, I'll be droping a 402 in there.
#45
As for cut outs, I don't think so. That is not my thing. It is not really a muscle car thing either. If you like muscle cars, you like a good sounding dual exhaust and a rumpety idle. It is just what the experience is and it is unique and cool. Opening up cut outs on the street seems like something Joe Dirt would do to me.
Some cars just make nice convertibles and the impala is one of them. I bet you will really enjoy that car.
#46
TECH Senior Member
Noisy valve-train is a result of:
>Tired parts
>Improper push-rod length and lifter Pre-load
Look at that.
Yeah, the Impaler is a sweet boat, I just got lucky locating it at the right price. Cosmetically, it is cherry besides I want good wheels on it.
>Tired parts
>Improper push-rod length and lifter Pre-load
Look at that.
Yeah, the Impaler is a sweet boat, I just got lucky locating it at the right price. Cosmetically, it is cherry besides I want good wheels on it.
#47
All new parts and I have tried lifter pre-loads from high 60s to just over .100". I have a pushrod collection. I even pulled the heads and installed LS7 lifters. Slightly quieter, but still too much noise for me. Geoff at EPS told me that headers temd to make the sewing machine louder. Anyway you look at it, I find it very annoying. It reminds me of the old solid flat tappets when the lash is really loose. In a car that is as quiet as mine, it is super noticeable.
#48
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Adjustable roller rockers (quality ones).
Hydraulic rollers should do just that, roll on the lobes and not bounce off them. Something is not right in your valvetrain, but it ain't the cam choice.
Hydraulic rollers should do just that, roll on the lobes and not bounce off them. Something is not right in your valvetrain, but it ain't the cam choice.
#49
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"in a car as quiet as mine"
You said you could hear the motor? So your exhaust setup must be pretty tame? The reason I point this out is because even radical cams sound very tame when coupled with something like a Magnaflow exhaust. My car idling through my Magnaflow catback sounds damn near stock...an untrained ear would barely notice the cam. Open the 4 inch cut-out and it goes into dragster mode. As you quiet, you tame...they are one in each other. I don't think you will even notice the difference (idle lope) in cams now that I know your exhaust is quiet.
You said you could hear the motor? So your exhaust setup must be pretty tame? The reason I point this out is because even radical cams sound very tame when coupled with something like a Magnaflow exhaust. My car idling through my Magnaflow catback sounds damn near stock...an untrained ear would barely notice the cam. Open the 4 inch cut-out and it goes into dragster mode. As you quiet, you tame...they are one in each other. I don't think you will even notice the difference (idle lope) in cams now that I know your exhaust is quiet.
#50
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"in a car as quiet as mine"
You said you could hear the motor? So your exhaust setup must be pretty tame? The reason I point this out is because even radical cams sound very tame when coupled with something like a Magnaflow exhaust. My car idling through my Magnaflow catback sounds damn near stock...an untrained ear would barely notice the cam. Open the 4 inch cut-out and it goes into dragster mode. As you quiet, you tame...they are one in each other. I don't think you will even notice the difference (idle lope) in cams now that I know your exhaust is quiet.
You said you could hear the motor? So your exhaust setup must be pretty tame? The reason I point this out is because even radical cams sound very tame when coupled with something like a Magnaflow exhaust. My car idling through my Magnaflow catback sounds damn near stock...an untrained ear would barely notice the cam. Open the 4 inch cut-out and it goes into dragster mode. As you quiet, you tame...they are one in each other. I don't think you will even notice the difference (idle lope) in cams now that I know your exhaust is quiet.
#54
That sure seems to be the case, but I do not even know what to look at to investigate. New cam, new lifters, new PAC 1518s, new rocker arms with Comp trunion upgrades. I currently have .082" to .087" lifter preload and it pretty much sounds the same no matter if it is .060" or .100". If there is a gremlin, I would love to know where to find him.
#55
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Wow. I've been thru the exact same crap trying to reduce valvetrain noise. The bad news for you is that I already have an EPS cam! I have new LS7 lifters, PAC beehives (changed from EPS duals to reduce noise), tried 3 different pushrod lengths, Comp trunion upgrade, and a new Melling oil pump. Just last week I changed the oil pump o-ring just to make sure it wasn't pinched. It's the quietest now its ever been with about .080" lifter preload, but I can still hear some slight ticking. The only thing I haven't tried is different lifters, maybe Comp's are better.
#56
Wow. I've been thru the exact same crap trying to reduce valvetrain noise. The bad news for you is that I already have an EPS cam! I have new LS7 lifters, PAC beehives (changed from EPS duals to reduce noise), tried 3 different pushrod lengths, Comp trunion upgrade, and a new Melling oil pump. Just last week I changed the oil pump o-ring just to make sure it wasn't pinched. It's the quietest now its ever been with about .080" lifter preload, but I can still hear some slight ticking. The only thing I haven't tried is different lifters, maybe Comp's are better.
This is my first LS engine. I have to say, the power, durability and ease of working on them is amazing. Before I learned about LS engines, if someone would have said 364 cubic inches that idles smooth and makes 400+ rear wheel horsepower, I would have said: "with what kind of supercharger?". The only thing about this format that I don't like is the valve train noise. I guess I can only hope for a future solution.
#57
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Besides Comp (or other) lifters I have a couple more things to try to reduce the noise. When I pulled the motor apart initially the foam insulators on the bottom of the intake were rotted so I just pulled them. I'll replace them when I do the lifters. I'm also thinking about header wrap insulation, that might quiet things down a little too.
Predator-Z has a good point that the rollers should roll on the lobes & not bounce off. I think it might be a case of the lifter reaching the end of its travel due to leakage.
Predator-Z has a good point that the rollers should roll on the lobes & not bounce off. I think it might be a case of the lifter reaching the end of its travel due to leakage.