Bcam to Xcam
 

sup guys, quick question, i got a B cam right now in my 347 thinkin bout switchin to Xcam for the added 7 or 800 rpm. i have the Y303 heads an to my knowlege the springs are good till bout .550 lift an i dont really feel like changin springs. so rules out alota the comps out there so i was thinkin the X. whatya guys think??

I wouldnt do it. I would just put 1.72 rockers on the B-cam that you have righ tnow.

Skyler

With the hyd. roller cams you are all done at 6,200 rpm regardless of the cam, especially the E,B,X,F cams. The lifter are just to heavy for more rpm and the cam profile is all done at 6,200 rpm's. Even tried lighter solid roller lifters on the hyd. roller grinds and still no more power past 6,200 to 6,400 rpm's. The reason why is that almost all cam grinders make the profile to fit the capabilities of the stock hyd. roller lifters, let alone the stock PCM is all done at 6,250 rpm anyway. There are ways around it but it costs a lot more money.

I saw a dyno test that had the X-303 up by 5 ft/lbs of torque at the torque peak and 10 hp at the top as well. It would have been less of a difference had th B cam been run with 1.7's but the extra lift of the X cam with a decent set of heads would probably make the swap worthwhile. Personally, I'd go with something like a comp cams XE 270 HR and 1.7's (.544 lift and a split duration). This is the cam that I'm thinking of going to, the B-cam is ancient technology wise.

I kind of agree with Sky on this. When I put my 1.7's on with my B cam, I noticed a huge difference. I would have to dig out the dyno sheets to get exact numbers, but it was a very significant gain.

A different cam altogether may do you more good, but throwing the 1.7's on is a very easy job as compared to changing out the cam.

retarding your B cam will move the powerband up about 400rpm or so, I did it to mine and noticed a big difference.

well as it is right now the cam with my combo makes good power till bout till bout 5800-6000, which i guess is pretty good but i guess i cant get much more than that accoring to u guys so ill prolly just stick with the B. thanx guys ;)

347
Bcam,RPM air-gap intake, gt40 heads, pullies, all MSD, crane rockers, BBK equal shorties, 750 edelbrock carb, flows, hurst shifter,

Anyone wanna guess what it ran on street tires an 3.27's? see how much u guys know:cool:

Well I've seen 347's run 14's and I've seen 347's run 10's. so theres alot more to consider than what you've listed.

BUT my guess, on street tires its probably about a 12.3@110 or so?

That motor is just beggin for some better heads and a good cam.

12.3's with 3.27's woulda been nice lol however ur mph was pretty close. best 60 ft. was 2.20.. what other info u want?

tranny, weather, track altitude....

well looks like its time to start focusing on getting the power that you already have to the ground. That 60ft is absolutely killing your times. The gears, although not nearly ideal, aren't your biggest setback right now, its traction.

Is your suspension stock?

With good traction, (ideally a pair of slicks) that should easily be an 11sec NA car.

the weather? i dunno maybe round 65 70 that day.. im from Mich. so weather is pretty inconsistent . the suspention is basicly stock, control arms front an rear all stock, i got subframes an urethane bushings thats bout the extent, although i got 4.10's an an auburn posi unit on the way. an ya bad 60's, wont hook for crap haha