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Thumpr cam

1870 Views 52 Replies 25 Participants Last post by  mrpaticular
I want to get a thumpr cam to wake up my big block a little bit. Yes I understand that this cam isn't as good as the XE series, but I really want that sound and anything is better than the original GM one. Motor is a 1993 454 that is stock besides a Performer 2-0 intake, 4011 800cfm carb and headers. Would the Mutha thumpr work or should I go with the thumpr? I know the biggest one will make it run like crap for sure

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I want to get a thumpr cam to wake up my big block a little bit. Yes I understand that this cam isn't as good as the XE series, but I really want that sound and anything is better than the original GM one. Look like I have 3 options? Motor is a 1993 454 that is stock besides a Performer 2-0 intake, 4011 800cfm carb and headers.

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One thing is for certain a thumper isnt going to wake up your BBC they were created for sound . Thats not what moves a vehicle Torque does. Next why would you want to buy an Xe series cam they have hasd lobe wear problems for decades and they still do. everything in engine building has to do with the correct combination of parts to achieve the desired results go faster . What you have to figure out your compression ratio static and dynamic and then buy a cam that will work for you . If its some of that cackle and thump thump sound buy a cam cut on a 108 lobe center witrh a short duration . Call isky up tell them eactly what you have and be honest they will tell you what to use and you will move fast and have your sound but the right way. Buying something just for the sound just wastes gasoline and makes no power for the fuel burned. You can do what you want but the advice i gave you is real world and solid . Remember i am not trying to sell you something or telling you what you want to hear so you buy something . Inform yourself ask around you will find out i gave you good advice from an old time engine builder. Alex
 

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One thing is for certain a thumper isnt going to wake up your BBC they were created for sound . Thats not what moves a vehicle Torque does. Next why would you want to buy an Xe series cam they have hasd lobe wear problems for decades and they still do. everything in engine building has to do with the correct combination of parts to achieve the desired results go faster . What you have to figure out your compression ratio static and dynamic and then buy a cam that will work for you . If its some of that cackle and thump thump sound buy a cam cut on a 108 lobe center witrh a short duration . Call isky up tell them eactly what you have and be honest they will tell you what to use and you will move fast and have your sound but the right way. Buying something just for the sound just wastes gasoline and makes no power for the fuel burned. You can do what you want but the advice i gave you is real world and solid . Remember i am not trying to sell you something or telling you what you want to hear so you buy something . Inform yourself ask around you will find out i gave you good advice from an old time engine builder. Alex
I also forgot to mention i think 800 cfm may be a bit too much what would have helped was car info Chevelle Camaro etc. transmission rear end and tire size everything has to work in unison to run nice . Alex
 

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There is scant dyno data with these cams but ill say that with Howard's, Isky, Clay Smith, Straub, Camking, etc.... lots of choices that will undoubtedly deliver deliver sound AND performance.

Provide a few details about your combo and perhaps you can get steered towards a cam that meets your sound goals and then some.

Personally, I run the Clay Smith 229/241 "old school" cam in my 460. It not only sounds bad to the bone but delivers in the torque/hp dept as well.
 

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Discussion Starter · #6 ·
Thanks for the information. I would absolutely go with a better cam but I am working on a budget and I am planning a complete overhaul for the motor in the future. At that point I will need to get another cam to match the new heads and pistons. Right now I need something to replace the rusty old cam, it won't be powerful so I want it to at least sound good.

I really just need to know which of the two I should go with for now
 

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Take the 227/241. At least you'll have a slim hope of chirping the tires, ha.....but if not, you'll sound good attempting it.
And hey, if that's what you want, go for it.

Any idea of your engine's compression ratio?
 

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Don’t Waste your $$$ on a Thumper cam, and Rusty Cam? You’ll want to buy lifters & springs to match the New cam, then do it all over again?
 

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Discussion Starter · #15 ·
Probably be much slower with the Thumper cam in a stock low compression 454. You will need a cam specifically made for 8:1 compression.
Could I up the compression a bit using new pistons? I can squeeze another few hundred into my budget, not new heads though. If yes then I might consider a different cam like everybody reccomends

Sorry im new to this
 

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do you understand the complexity of changing valve lift on this engine with non adjustable rocker system? that's not an insult- just not as easy as older Chevy V8's, maybe look for a lower lift cam with a tight LSA
 

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One thing is for certain a thumper isnt going to wake up your BBC they were created for sound .
Oddly, they don't dyno all that bad, the data is out there. Go for the smallest one if you must, but I may add two things AND what PCB Bob said above, that would be a deal breaker.....

1. I don't prefer lump unless it runs 10s , butt that's me I am sort of a "nazi" about some things ( well I'm Ukrainian so ) its my opinion, so disregard that

2.) IMPORTANT! "Heart surgery" isn't something I'd do nilly-willy on a rat, There is a risk of cam lobe/lifter failure, now more than in 1990 . Then what?

Me, I'd drive it until I could do it properly. A "rusty " cam may change that advice tho. I hope you were just embellishing.

If you simply can't help yourself and you MUST, DO NOT buy off the shelf from a box store. Get with Mike Jones, aka Cam King and at least get good parts. With a4 speed you best use good springs, as the risk of overrevving is there. Mike can dial in limpy if you want it, adn make it work with 8:1.

You know, sometimes an 8:1 454 with a decent cam is surprising. I know mr 4 speed's womans 69 Chevelle run 12's with an 8:1 454 and a Summit cam. So its not like it wont work!

 

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Thanks for the information. I would absolutely go with a better cam but I am working on a budget and I am planning a complete overhaul for the motor in the future. At that point I will need to get another cam to match the new heads and pistons. Right now I need something to replace the rusty old cam, it won't be powerful so I want it to at least sound good.

I really just need to know which of the two I should go with for now
I'd save and increase the budget and do it right the first time. We average no 1 a week calling with a flat tappet that has gone bad and customer is rebuilding engine and going hyd roller. GM 602 Crate engine cam and lifter failure is through the roof right now.....these come with new GM flat tappet lifters from GM...
 

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I'd save and increase the budget and do it right the first time. We average no 1 a week calling with a flat tappet that has gone bad and customer is rebuilding engine and going hyd roller. GM 602 Crate engine cam and lifter failure is through the roof right now.....these come with new GM flat tappet lifters from GM...
I must not pay attention enough. I thought gm went away from flat tappet lifters in their crate motors. Especially in big blocks
 

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You know, sometimes an 8:1 454 with a decent cam is surprising. I know mr 4 speed's womans 69 Chevelle run 12's with an 8:1 454 and a Summit cam. So its not like it wont work!
[email protected] 111 MPH w/3.42 gear and 87 octane
Engine is probably 15 years old now.
Less than $2k into the build.
Wheel Tire Car Land vehicle Vehicle
 
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