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Digging through the piles of paperwork on my vette, finally found what cam is in it.... Thinking about changing to a ***** thumpa...what do you all think?
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
I would look for a Extreme energy, Nostalgia Plus, or Factory Muscle if you are looking to drive it and have the vacuum systems work...https://www.compcams.com/cam-series
Digging through the piles of paperwork on my vette, finally found what cam is in it.... Thinking about changing to a ***** thumpa...what do you all think?
What do you think of the current cam and what is your motivation to change it? Since you have the specs on it, you are in a good position to evaluate another cam's profile for how characteristics and performance will be changed with a swap.
"All sound and no power".. not necessarily.
The largest Thumpr is almost equivalent to the Oldsmobile Stock Eliminator Cheater cam from the '70's. It was,( is, still available to buy) 243/262 @ .050 and on a 107* LS too, a lot of races were won with it also, (and YES it thumps hard). But the thumprs will waste fuel and power if you have great exhaust flow like in an AFR SBC head could in a street car application.
Howards Cams Rattler cams are also on a tight LS @ 109* and may make a better more streetable cam. Lunati's Bootlegger cams are a 108* LS.
Digging through the piles of paperwork on my vette, finally found what cam is in it.... Thinking about changing to a ***** thumpa...what do you all think?
You are literally considering going from one end of the scale to the other, 114* to 107*, you'd notice a big difference if the same cam was on a 110*. I used a normal circle track cam in our stock car (350 ci) and it was 234*/244* @ .050 and on a 106* LS and you'd think it was much larger when at idle , it sounded very mean - and it was. Not street friendly tho' !
Thumper Series Cams are a great stereo sound effect for less knowledgeable car enthusiasts.
Or, in laymans terms. All sound no power. Save your money.
And I hope you have one hell of a short-block and rear gears to go with all that duration.
I hear that regurgitated quite often....as mentioned....they have made some serious power for what they are...and some "custom" cams mimic the specs. They generally have a large 'soft" exhaust lobe which causes a lot of overlap (for sound)...but in some combos that can help. Yes..that overlap will hurt vacuum a lot if you need it.
LSA is a byproduct of the lobes. You can "rock" the curve around a little by changing it...but it's entirely possible to have a "tight" LSA cam and have pretty darn good manners. Depends on the size of the lobes and how aggressive they are. I've got a 106* LSA solid flat tappet in a blown 408" engine that fires instantly and idles clean with incredible response. All "wrong" if you listen to some folks...perfect if you validate what others have done. It's got some pretty aggressive lobes.
Since you have a big block (cubes?) and a tunnel ram.....I'm not sure if you're more worried about power or sound? What's the rest of the combo? Compression, heads, carbs, trans, gearing?
I hear that regurgitated quite often....as mentioned....they have made some serious power for what they are...and some "custom" cams mimic the specs. They generally have a large 'soft" exhaust lobe which causes a lot of overlap (for sound)...but in some combos that can help. Yes..that overlap will hurt vacuum a lot if you need it.
LSA is a byproduct of the lobes. You can "rock" the curve around a little by changing it...but it's entirely possible to have a "tight" LSA cam and have pretty darn good manners. Depends on the size of the lobes and how aggressive they are. I've got a 106* LSA solid flat tappet in a blown 408" engine that fires instantly and idles clean with incredible response. All "wrong" if you listen to some folks...perfect if you validate what others have done. It's got some pretty aggressive lobes.
Since you have a big block (cubes?) and a tunnel ram.....I'm not sure if you're more worried about power or sound? What's the rest of the combo? Compression, heads, carbs, trans, gearing?
JIM
You are correct and let me rephrase my "no power" statement. The Thumper Series can make power, lots of power. But it's for street use. Its the cam that gets a lot of attention when you pull into a car show. It has the sound of something really big & powerful. Lots of show.
However, those weekend warriors that hit the tracks every weekend would not be using a "stereo" cam like that. Its not for serious bracket racing and the like.
To each their own.
If you want to hear some sweet sounds out of your Corvette try finding a good Chambered Exhaust system. I have a high compression 427 and it makes sounds like side-pipes but the "noise/Music" comes out the rear of the car. I also have another Chambered system on a 1988 with it's L98 engine making a whole 255 hp. With the chambered exhaust people are pretty sure I have modified my L98 because it sounds ferocious with the burble from the factory cam. I get a lot of nice compliments on the sounds of either of the Corvettes as the exhaust system was a great move.
When I buy a camshaft, I buy it to make Power, I have never bought a cam because of the sound the engine makes with it. With either of the two Corvettes with Chambered Exhaust I can speak in normal tone with a passenger. It is easier to hear inside the C4 as it is a coupe but my C3 convertible it is difficult to hear anything but the engine while accelerating. Under cruise conditions I can hear a passenger even with the top down.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
Cheap doesnt equate to good quality...never has. I definitely understand the limits of a budget though.
Luckily i can now afford higher quality parts and am willing to wait to afford it. I just dont want to buy cheap parts anymore because they usually need to be replaced sooner than later. Which adds up.
Cheap doesnt equate to good quality...never has. I definitely understand the limits of a budget though.
Luckily i can now afford higher quality parts and am willing to wait to afford it. I just dont want to buy cheap parts anymore because they usually need to be replaced sooner than later. Which adds up.
You definitely have to be aware of false economies
Nostalgia+ LS6 replacement from Comp gets a big thumbs down. Had two of em, one failed when SM oil came out in 2005 and I wasn't paying attention. Second one never ran well. Thumper cams? Don't do it. You will hate it. The cam specs you're showing are ok for hydraulic, too small for solid I'm running a Crane solid, 236/248 duration at .050, 114 LSA, about 550 lift on both. Very close to the factory L72/71/LS6 cam. I'd recommend it or a repop factory solid lifter cam on 114 LSA any day of the week for a street driven car.
Not ever doing hydraulic on a big block again. Tried a couple of Comp hydraulics. XE 274H ran ok, almost like the factory solid, but flat out fixed at 5500brpm, Luke shutting the key off. It floated valves at 62 to 6300 no lead revving. The solid cam blows right through 7000 without a sputter. Runs strong to 6200 through factory exhaust manifolds.
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
I learned the hard way...and it applies to all expensive hobbies....bicycling, skiing, kayaking, mountain climbing, competitive Shooting and of course women, i mean cars
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
IVe got that LS6 cam in the box...what oil are you talking about and what didnt you like about the cam....im going to start a new thread so i dont hijack this one. I will post a link
IVe got that LS6 cam in the box...what oil are you talking about and what didnt you like about the cam....im going to start a new thread so i dont hijack this one. I will post a link
Cam discovery
