Comp Cams Thumpr vs. Xtreme Cam Sound Comparison 

mutha thumper is the second one right mid teir

Get the right converter youll love how it drives SO much better. Stock stalls and lopey cams are a real disappointment

Yep its the cam

@@KGisthename Blowing the intake charge and torque right out the tailpipe lol. But it sounds good so...

UNless you gear that vette Id stick with a isky 270 or 280 mega cam tops. YOu need lots of torque that thumpr will disapoint

That's all it is for basically

I have a mutha thumper in a STOCK 454 bbc, with headers, intake. Pulled way harder then the extreme energy cam. I did same comparison. If your not afraid of stall the rattle. Let it thump

@@zombieking712 not true

@@adamstreitz5089 What was the specs of each cam? Look at it this way. The Thumper is basically a relatively mild intake lobe with lots of exhaust duration and some added LSA to keep things running. So you could get say a 232/246 LSA 112 for instance which will sound pretty rowdy in a 383 for example, but it will be relatively mild. And like most cams with a wide LSA, it will be soft down low and in the middle. High LSA cams like to RPM. Now make a cam that has a 230 intake, but 234 on the exhaust and a 108 LSA, and you can be pretty sure which one will make the most average power. The latter will obliterate the former no matter what you do with gears etc. They will sound about the same, but they will drive very differently, and the midrange punch in the 108 LSA cam will be brutal compared to the 112 LSA cam.

@@zombieking712 It's not all, but it is the main objective.

Havent heard of that grind in many yrs. Sounds similar to the hyd 280 mega cam Small solids most never even heard of but they are a blast on the st. Best running 350 I had was a 10.3 to 1 350 270 cfm head Isky 280 mega Holley 300-36 and a 650 double pumper. Holy cow that thing litup tires NOW! Even with the wrong 308 gear and a not sufficient 2800 stall. 750 was way too much carb

Tried a low (barely 10-1) build like that yrs ago and was disappointed. What works on thier dyno didnt add up on the st. Firm believer in compression gears makes all the difference in the world. You can literally hear it in the tailpipe while driving.

256 was a way better choice for him....thumpr, bootlegger etc need compression lots of initial timing, gears, stall to even work. Sad so many choose cams by a video and have no idea that most times they will be driving a turd .

@@gordocarbo yep agreed always check your squish and your dcr before you buy a cam

They don't recommend efi with the thumpr

@@briandcarey3110 Agree, totally wrong cam for EFI especially throttle body. WAy too much overlap

There has been dyno comparisons done by one or two of the engine masters guys. The thumpr cams surprisingly made a small bit more power and torque than the extreme energy series. Kinda surprising I know.

I would think the thumpr cam would make most of its power in high rpm

@@brendanscott5023 it tops out at 6200, it has a nice broad torque range surprisingly.

All things being equal, the "thumpr" cam will give it better performance!! It has more lift, more duration, and will raise the power ratio. More air/fuel mixture in, means more compression/power out. Unless he's got a stock converter, he will gain more performance from the larger cam.

@@brendanscott5023 It rally depends on your engine. But wide LSA cams which the Thumpers usually are, like to RPM.

With the thumper, you can have both. Anyone who tells you different, either hasn't tried one, or did not use the proper gearing, stall converter, carburetor etc.

@@evorider3689 You can run a lot less aggressive cam, and get plenty of power and sound. Thumpr is very inefficient. Many cams much smaller do the job better and still sound good.

@@gordocarbo I was explaining to @aljackson, that the Thumper cams do make good power! ( I know that from personal experience! ), and yes I am well aware that one can achieve plenty of power with a less aggressive grind, however a big part of what gives the Thumper cams the VERY lopey idle that car guys like so much, is the long duration, and as I'm sure you are aware, a cam with a lot less duration (like you are suggesting using instead of the Thumper) will not produce the extremely lopey idle that the Thumper produces, and that is what so many hot rodders crave! Yes the cams you are suggesting, will be more efficient, but they will not sound AS GOOD as the Thumper.

ThT why he should take out the thumper cam and put back in the extreme cam in.

@@w41duvernay Not a fan of those either. Ramps for a ft are too steep imo. Had 3 fail back to back, when they first came out. XFI280 roller, too. Unreal

Use another brand, or line of cams.

Not unless you want to lose power.

@@w41duvernay let's be honest man with an older car like that sound is always going to be better. That thumper cam made it sound like a real muscle car. Definitely going with that on my small block.

@@w41duvernay I wouldn't say that. Depends on the combo

Agreed put it back on it sounds like true American muscle with the the thumper

I agree put the thumper cam back in the extreme energy cam sounds like a Farmall H tractor

I definitely agree with that statement!

My old 350 made more torque overall power with the smaller Isky 280 than the XE 284. Geared right single patterns hit harder, just choose a realistic powerband. The extra 5-10 lbs you Maaaay get from teh XE isnt worth the accelerated wear on valvetrain parts.

We both know the answer and it wont be popular with novices

It is a great sounding cam that's for sure!

Is the vacuum decent?

@@johnsheetz6639 they have very decent vacuum when you use it with proper compression ratios.

Glad it worked out good for you! That's good advice also

Correct. avg st sb, 2teens@ 050 cams usually run best overall. GOod torque brakes easy to tune etc Like big cams too but it needs lots of supporting mods or its just a pooch that sounds good

and A LOT of initial timing. Ive heard people had to limit their mechanical advance to where they ran 20 degrees or more initial...

@@KingJT80 not so much really.

From my experience with the Thumpr cam the power came in at higher rpm like most big cams. For an average engine like mine I won't rev it high enough to really get all the benefits of that.

@@Jay-fb2lv Well compared to most people who just run 14 15 degrees initial on a street performance cam. its getting up there. one guys said he ran 24 initial and 36 total. cleaned up the idle and he didn't have to jack around with the mixture screws or the idle circuit

@@KingJT80 that’s because he didn’t have as much compression as he thought he had.

yep. Many overcam and their powerband isn't realistic on the street and then they get blown away from the stoplight with a stock motor. Lighter vehicles get by with it more but say a big car or 80's truck forget it.

@@drdjh2003 Well said!! Some of the best running st cars are mild torquey combos. Hard to beat overall. Lope doesnt mean fast thats for sure

Too much overlap idle circuit needs more tuning. Have 82 deg overlap 0 soot inside mine

Bad decision, esp for a heavy car. Im one of those fail stories...all same fast ramp cheap core crap. Even a roller went flat. Lope doesnt equal fast. You need torque for that car, easy on the overlap, duration. Youll go faster with going smaller to a point.

Thank you! Some day I'll start working on the body of that thing!

Get a vacuum canister. I'm running that cam also.

Yes

No, it means it will work well from idle to 5000 rpms, but will not achieve even anywhere near Max toque at idle, or just off idle. But you will have very strong low rpm torque!

You have the older high energy 268. The newer XE268 has 224-230@50

It depends on a lot of different factors! My friend has a 350 with a thumper cam and the car is a beast! A short duration cam will give you more low end torque and much better streetability, but the car will not be the beast that a car with a long duration cam will be, provided the car with the big cam has the appropriate gearing, compression, etc.

@@evorider3689 Last few items most car guys skip or cheap out on. Springs, supporting mods dont recurve the dist and wonder why thier car sucks.

Exactly!@@gordocarbo

There's always a better option for power.The Thumpers are for show more than anything.

I wiped out my solid roller cam and lifters. Not good for street, especially if you don't keep on checking lash and are idling it alot. Engines basically brand new. Now I'm looking for a hydraulic roller setup. That big Mutha thumper sounds badass. I won't be racing my 383, except racing to the fuel pump, so the heavy over lap and duration don't bother me. It's just for cruising

I ran a big mutha thumper in my sbc. It was a monster. It was in a 4 Dr. 2wd blazer and it ran 12's on street tires. The cam makes good power it's not only for sound

X pipe at a little before the center of the car

Valve overlap is the Cause for a lumpy idol the more valve overlap I.e. duration you have the lumpy it gets, Da dumpity Da dumpaty Da dump Da Dump 👌

@@boosted. you just said what the op said...

@@nsmturbo5902 Lobe separation is not duration or overlap

@@boosted. Overlap is the degrees that both intake and exhaust valves are open at the same time. That is determined by Lobe Separation Angle. I didn't mention anything about duration... All I said was you are both saying the same thing.

@@nsmturbo5902 true and the more duration the longer the valves hang open and the more overlap you have I guess we agree maybe didn’t understand what each other was saying

They need a a lot more initial timing and compression than people think. its a "big camshaft" the one he had was pretty big and if he didn't have 10:1 minimum its gonna suck. esp on vortec heads. if he had the smallest of the 3 aka the thumpr , it wouldn't have been that bad cause vortecs have sucky exhaust ports anyways so its needs that extra duration

He got to get the 279 thumper cam that the small one

@@KingJT80 what are your thoughts on a thumper in a 5.0 Ford? I have an f150 thats to nice to beat on so it gets driven to go get ice cream and to shows only...maybe deck the heads bump, compression port em to the max?

@@desmondpeak9931 yep

Thumpr cams are better suited to strip and racing applications. They actually make more power on the top end with a wilder setup. On a street setup they make the engine run like a fat pig at low RPM.

Little rich is better then a little lean though!

@@ZanesGarage true I finally got my truck to run pretty good it’s an old tbi 350 so it hates bigger camshafts but she eats it now

@@TheUndertoe Engine dont love to run rich...nor too lean.

🤣🤣👍 so true, if only idle quality was the direct key to HP produced!

Those two cams are so different its tough to compare. Id take the smaller one all day and 2x on sunday for an EFI driver.

It will make tons of vacuum thats a real good torque cam. 206 is a little better than stock but almost not worth upgrading from stock. THat 211ish to med teens @050 kicks butt on most st sbc, Lots of torque everywhere.

Its going to be more hassle tuning it. Those have a lot of overlap, not great with EFI. DOnt worry about lope just get the right one and do your tuning

Similar approach as thumprs actually. Comp owns them so no surprise theres a new line of cams with a catchy name. Harold B would never let stuff like that take place if he were still around...whatever floats your boat though

@@gordocarbo How do you figure Comp owns Howards? Because they dont! The rattler series is nothing new its name is from the Howards slingshot dragster that was called the rattler. The grinds have less duration than a thumper and the lsa is on a 109 a comp thumper is on a 107. Howards is made in the USA. I think you are getting Howards mixed up with Crane.

@@wildrosegarage4208 I said they own lunati not howards

Smoother cam just has a ton less duration and overlap. Trying to make a cam whose ramp is too quick is just gonna wipe out lifters and lobes..if you need more just choose a different cam or better yet toss a bigger crank in it

What would you recommend?

@@falcon6995 a stock 5.3 lol

@@RazorUltraPro11 you don't need a stock 5.3 lol just put a set of cheap 180cc aluminum heads and flat top pistons in a 350 and a 230s duration cam. Done 430+

Lol last guy said it kinda. Heads, man, heads. Whippy little cams like these aren't bad in any way, give a bit of extra bump in the power but then again so can a quality tow cam, anythings better than most stock choked up cams. The best part is being able to change how the motor acts. But none of it matters for power without heads. Get good heads first and you'll SIGNIFICANTLY increase how much power even a decent little cam can make. Heads are expensive even when theyre cheap, save up for a pretty nice set. Then you can get whatever cam you want and actually see it's gains.

@@-OokySpooky- yeah it always works better with better heads then you don't need as much cam duration.

Looks like a nice ol' Maverick!?!!

Maybe In a video some day! It's a stock 302 so it's nothing crazy

Nice ol' Comet actually! Same thing though lol

@@ZanesGarage My mom had one- hauled ass pretty good with a 302! I was about 10, so everything seemed to be fast- when my brother drove! :)

Oh yeah they're pretty snappy that's for sure! I'd love to build one into a real hot rod some day

Oh your right! It is an xtreme energy cam the one that i have linked but i must have made a mistake on the intro and said high energy. Good catch 👍

I've seen a couple say it works. Some say it doesn't.

The less vacuum at idle makes it run higher up on the base fuel table . The map signal will also be more irratic. You can tune around it but it's a lot harder. You can also use ALFA N VE COMBO to get around that too

Too much overlap, rediculous duration on exh and crazy tight lsa. Not gonna play well with EFI Just put the right cam in there it will run and sound just fine.

Yeah the smaller cam definitely feels faster and much more responsive. I need to hit the track with it to really test it out!

Your both right it was an old belt on a misaligned alternator! Fixed now 👍

Great job! It should sound real nice now and the tighter LSA will make more power for you.

So far it's great! Ive had it for years now. I had an ECU die a year or so ago on it but after contacting Holley I sent it back and it was replaced and taken care of. 👍

Comp doesn't recommend efi with the Thumpr cams

You can get a decent cam kit for a little over 200 dollars and that includes new lifters so it really isn't to bad. Now I replaced my whole bottom end so add in a crank, rods, bearings and pistons (reused the block). It adds up quick but I enjoy it so it's worth it to me!

A cam swap can be one of the cheapest ways to gain hp and or torque depending on what your after if you just wanna sound cool the mother thumper sounds great but unless your set up for a big looper like that you won’t gain much power and in some cases you may lose power.

Could one install that thumper cam in a carbed chevy 350 without any other supporting mods? I already have a edelbrock carb and head back exhaust.. just want that lope

@@joeyhurwitz2930 yes 100%

@@ZanesGarage No you cannot. The cheap lifters are the worst thing you can possibly use. I've seen as much as 35 hp loss due to crap hydraulic lifters, not to mention the bill down the road when one of them loses a bearing. If you upgrade your cam, getting such cheap lifters is insane. Lifters run in the 500-800 usd range, that's just life. No free lunch.

Sounds like an awesome build! And i think as long as your comfortable tuning those carbs and getting them just right then the Thumpr cam will give you that classic sound. If you don't want to worry about that stuff then I'd stick with one of the more mild cams. Good luck on it!

I went with the retrofit, to many horror stories about ppl whipping lobes off,

Choose another line of cams then.

I'm not sure what specs are considered "big" for big blocks so I can't really say but it depends on your heads/springs. The more duration, tighter lobe separation angle and higher lift a cam has will make it sound more radical.

The higher you go in lift the choppier it will be, I wouldn't worry about the sound, if you're running on the street I wouldn't go much further than .500 lift, you want it to have decent street maners if it's a street car, .500 is right on the edge of ragged, make sure your heads peak flow number top out around the same lift

Not enough information to recommend anything. Call a long time cam mfr with some old timers who ask a lot of questions before giving out cam grinds...or better yet your machinist will know exactly what will work...internets or guys answering a phone looking at cheat sheets is gonna net you a poor result

If you mean does it need to be modified no it doesn't. But depending on the engine you might have to notch pistons, change valve springs or upgrade rocker arms. That being said if it's dead stock you won't get all the sound, exhaust manifolds and restrictive mufflers will ruin the sound. As a side note you might have to change the convertor too, what happens is the new cam changes the torque curve and the car will lock up the convertor at idle and will push through your brakes at a stop light. Not trying to discourage just trying to inform

It will all depend on what springs, heads and pistons your engine has mainly. If your springs can handle the lift of the new cam and you have the piston to valve clearance you should be good. Try and get some info on your combo and you'll find the right cam for it 👍

You're the only one here that gets it ? Right. Just fun to sit at a lite and idle. And cruz.

@@TL-angzarr correct. I had my thumpr put in two years ago, but with stock springs and stock convertor. My headers were cut open after the y pipe prior to the cam. Even after adding a vacuum canister last year, my car still wants to go when in gear and brakes engaged.

I wouldnt. it will be a slug

I'd love to turn a comet or maverick into a drag car someday! This one is to clean to do that to it but someday!

Right duration and Lobe separation angle will make the biggest difference in sound and idle quality

From my understanding duration will give an engine a choppier sound and poor street manners. But the reason why is intake and exhaust valve overlap. So you can still have a short duration cam with choppy idle. Now the low vacuum from a bigger duration cam comes from when the intake valve closes. Basically all cams close the intake after the piston has already started it's way up on the compression stroke. Intake air still has momentum to force it's way into the cylinder as the piston starts going up. By keeping the valve open longer the piston is able to push air back into the intake lowering dynamic compression allowing you to run higher static compression without pinging on the same octane fuel at lower engine speeds.

nashvilleoutlaw yes what he just said, if you want to get the chop sound better make sure you are running 11:1 or more compression or you will pay the consequences and no you should not run LSA below 110 with electronic injection and all thumper cams are below LSA 107. Most modern fuel injection have LSA above 116.

No, its overlap. Its the intake charge trying force its way back UP to the carb....trying to make it not run essentially. Less is more on a true st car...lope is wayyyy over rated.

there are . Back when we were kids and people raced cars, trucks outside of our country town if you had a stockish car or truck and stuck a 292 cam in it, no gears , converter it was a dog. The vehicles with dual plane intakes, 268 HE comp cams were always solid performers, and great everyday drivers.

Gotta have decent flowing heads, everything has to match up

@@drdjh2003 True. That 218 high energy or Elgin Isky Crower version is the perfect st perf cam you can drive every day. They will run hard from idle no issues....ramps are not crazy "extreme" so the cams last too. Prefer pre 2000 grinds for most cams

You're best luck would be to call Comp or read around on forums for your combo. I ran a stock style converter with low stall and it definitely wanted more. Good luck!

Comp Cams Xtreme Energy Cam Part # 12-234-2 Lift: .447 Intake / .454 Exhaust Duration @ 050: 212 Intake / 218 Exhaust Lobe Separation Angle: 110

Thats the old RV type cam...lil better than stock but not a bunch.

Never taken it down the strip to find out. It's all stock as far as I know so it's not breaking in records lol

Yes, I'm running vortec heads on my engine that is in the video actually. They can be great heads I really enjoy mine.

96 and up 350sbc The old 80s or earlier centerbolt valve cover heads are NOT vortec..nor the 305. Lots selling used "vortecs" that are just crappy smog heads.

Yes I did I run a walboro 155 I believe. You need to have a fuel system that can run at 60 psi as well as a return line.

No one ever taught me and I'm definitely not an expert but the only way to learn is by doing it! (And messing up a lot)

Mr. E ant nothing to it but to do it man. Buy a how to build an engine book and read it. Make a list of the parts you want to use and research how they will work together before buying anything. My current build I'm working on is a 9:7.1 383 with AFR 195 heads and comp xr288hr. Shooting for close to 500hp in my El Camino that can still run 87 octane because I like to drive mine.

@@nashvilleoutlaw awesome. Good advice. I read everything about the 4 stroke of combustion and understand how they work internally, and that was at 16. I am 48 now. Maybe someday. Need a buddy to do that with me. More enjoyable.

@@mr.e1220 yea nothing like building a project with friends. I'll give you a couple of pointers on building an engine. Buy pistons with a small ring pack because engine will last longer and you get an extra 8hp or so up top. Cam will determine the compression ratio you need. Everybody talks about static compression, the measurement of piston travel from bottom to top dead center. Very few mentions the camshaft controls dynamic compression. That's the measure of where the piston is at intake valve closing and piston reaching top dead center. That is a big determination of what octane and static compression you can run because the intake valve closes after the piston is on it's way up. That leads into why low runner velocity and to big of a head are bad because the piston will push air back out of the cylinder with low velocity runners at lower rpm. There's you a few bread crumbs to follow lol

@@nashvilleoutlaw thanks 😊

Yes, it is. 72' with a 302 fun little cruiser

Sounds like somebody didn't have subframe connectors and upgraded torque boxes lol

No you dont who told you that? You can run stock mufflers no problem. Headers help

​@@gordocarbo You can have cutouts with stock mufflers. Do you know what cutouts are?

Thanks and I totally agree. Hopefully I'll get to test it at the drag strip some day soon.

the thumpr one sounds good

Comp doesn't recommend efi with the Thumpr cams, says so right on the page

I get that about the hype. They sound good but so far this new cam seems way more responsive!

Zanes Garage I’ll look into it! I caught wind of your channel from sniper efi videos and I’m staying for the content to come!

@@MRTX1500 please do not get a mother junker cam. They're ground for sound with NO PERFORMANCE

I bought a mutha thumper for my 83 TA 350/5 speed because of the hype from all the magazine types. Hard to tune, disappointing power with the best sound by far. I’ve had it 10 years but barely drive the car because the power band sucks in traffic. May do this swap but was thinking about going roller.

The Big Picture exactly why I decided to go back to the stock cam. I had it laying around. It only cost me some time but that was it