|
 |
||
|
 |
|
|
||
Cams and exhaust: 174x8 and TBR vs. 153x1 and M4.
| Description | : | I get a lot of questions about cams and exhausts. A lot of the racers think they have to have the 174x8 because it is the "race" cam, and the TBR pipe because it has the "big" headpipes. Bigger is always better right? This chart shows otherwise. Up for comparison are 2 Hawks, both with 700cc kits and my Stage 2 heads and stock carbs with 3.0 jet kits and pod filters. Run .004 is the 174x8/TBR bike, and Run .053 is the 153x1/M4 bike. Now, I don't want you to get all caught up in exact numbers and stuff because the 174x8 bike "should" make a couple more peak hp, but its being held back by K&N filters. I do want you to look at the shapes of the curves and the midrange. Which bike would you rather race? That's right, the one with the so-called "street" cam.
The 174x8 cam is a product of a bygone era. The cylinder head technology then sucked, so the solution was to put more cam to it in hopes of increasing power. Well, it did increase peak power but at great expense to the midrange. Fast forward to the 21st century, and with 20 years of cylinder head technology applied we don't need that nasty 174x8 cam anymore. Big valves + little cam = big power spread. Also, this chart proves that the smaller M4 headers work fantastic. They help fill in the midrange nicely. Most of the midrange difference is the cam, but some of it is the exhaust. |
|
|||||
|
| Powered by Gallery v1.4.4-pl4 | RSS |