![thumper cam 350 hp thumper cam 350 hp](https://www.motortrend.com/uploads/sites/21/2008/08/hrdp-0808-01-ps-comp-cams-cams.jpg)
I know of a couple guys going mid 6's in the 1/8 mile with a Thumpr cam, and I've personally installed 4 of them in engines myself. That being said, if this is a cam you like, by all means go for it.I'm curious as to how many of the folks who talk down the Thumpr cams, have actual experience with them? Have any of you guys ever been around one, or ridden in a car that has one in the engine? I think I already know the answer, as if you had you might change your mind about them.
Thumper cam 350 hp series#
But the above example is just one of many that you can find on the web where the power output of the Thumpr series has been put to the test.and come up a bit short.īut then, by Comp Cam's own statements, that was never the purpose for the design of this cam. In addition, I don't claim to be any sort of engine or cam guru. I understand that it is always problematic to compare different dyno tests done under different conditions with slightly different engine modifications. That's 77 HP more than the low end Thumpr and 42 HP more than the high end Thumpr. The XR276HR, on the other hand, produced 412 HP at 5600 RPM. You'll have to judge for yourself the impact of that difference.Īs shown in the link above, the three Thumpr models produced from about 335 HP to 370 HP at 5600 RPM. One difference that should be noted, is that the Thumpr used hydraulic flat tappet while the Popular Hotrodding test used hydraulic roller rockers. The only major difference was the substitution of the Comp Cams XR276HR grind for the Thumpr.īoth dyno tests were done by Westech (so probably the same dyno), both were started with a basically stock 350 crate motor (290 HP), both utilized RHS 64cc heads, and both utilized a 750 cfm carb. Popular Hotrodding did their own dyno test of a 350 which was basically set up the same as the Thumper Dyno test.
![thumper cam 350 hp thumper cam 350 hp](https://static.speedwaymotors.com/images/charts/282126004.gif)
While CompCams does not provide side by side dyno comparisons, heres a quick one I put together.
![thumper cam 350 hp thumper cam 350 hp](https://i.ebayimg.com/thumbs/images/g/wAkAAOSwpBpdIDv6/s-l200.jpg)
The Thumpr results also include the addition of a 750 Holley to the set up, while the "stock" results use a smaller 650 Holley.īut even that doesn't give you a very good picture of the Thumpr in comparison to other cam grinds.
![thumper cam 350 hp thumper cam 350 hp](https://i.ytimg.com/vi/FNIw0DM_vDs/maxresdefault.jpg)
The only trouble is that you need to read the specs closely to discover that those numbers don't compare apples and apples. In fact, at first glance these results look to be promising, about a 35 hp to 55 gain for a 350 crate engine at 5600 RPM depending on the Thumpr model chosen. In all fairness, I think the above quote is probably just a bit of poor ad writing because the dyno test results posted by CC do show a horsepower gain over a stock cam.
Thumper cam 350 hp install#
".Maximizing the rough-idling characteristics.without negatively impacting the power output.? To my knowledge that's the first hi-perf cam grind I've ever seen whose claim to fame is that it doesn't actually reduce your engine's horsepower when you install it. "The reason that the new Thumpr Camshafts have such an aggressive exhaust note is that the lobe profiles and grind characteristics chosen by the COMP Cams' engineers produce a combination of early exhaust valve opening, long exhaust duration and a generous amount of intake and exhaust overlap to maximize the rough-idling characteristics of the cams without negatively impacting the power output or streetability." Notice here that the selling point is not torque or horsepower as compared to other cams. In fact, one of the most frequent questions fielded when customers call our CAM HELP tech line is "what cam will give my engine a mean-sounding idle?" In response to this popular demand, the COMP Cams' engineering team proudly introduces the Thumpr series of camshafts." "Let's face it, few things serve to grab our attention at a car show or cruise night more than a car with a thumping, high performance idle. They follow that with an explanation of their motivation in creating this particular cam series. The tag line for the cam (as shown here in CC's advertising) is "BE LOUD. Rightly or wrongly, Comp Cams has adopted a marketing strategy for this cam series that emphasizes the bark over the bite.