I already have a 4-bolt main all forged short block and was wondering what type cam should I run with an s-trim. I noticed that some guys run solid while others stick with the XE grinds. The car will only be driven every other weekend, it will be garaged otherwise. I am lookly to make the most hp that I can, driveability is no prob as it will be for takin out on nice weekends to taunt stangs. So what do you guys think. I am trying to get all the parts so I can get started when I return to the states from my deployment.

thanks, Charlie

 

With the current state of HR technology there would be very little reason to go SR unless you were building a race car. The more agressive HR lobes have nearly as big an "area under the curve" as comparable duration SR lobes. So, a "big" HR cam and a "small" SR car are pretty comparable. If you are planning on running up to the 7,000rpm range, or more, than you need a SR in order to be able to utilize enough spring pressure to control the valve train at these high revs, as well as allowing lobes with enough duration and lift to support the high rpm.

I was considering a switch to SR this year, but am going to stay with a HR setup for the reasons above. Basically, I don't need the SR so why put up with the hassle of periodic valve adjustments and the costs associated with the switch over.

Rich Krause

 

Yeah thats a good point, I think that I will go with a big HR cam. Do any of you guys have suggestions on what size or which manufacturer. I was thinkin of goin with a compXE grind.

 

The only other point I would mention with respect to SR vs. HR is drivability. If you are staying mild or this isn't an issue then the hydraulic roller will be fine, but if you want a high effort but very streetable NA motor a SR has quite a bit of potential. For instance I have driven a 250/254 SR 396LT1 and a 396LT1 with a 306 as well as extreme230/236. The 250/254 solid roller car was easily the most streetable of them all - with a capped borla it sounded virtually stock (well, stock with an exhaust and headers) - it also made ~30+ more rwhp than the 306 based setup (the extreme ran into the common valvetrain issues), and had much more area under the curve - 70 more ft-lbs of torque at 2500rpm.

Now there is alos a distinction between streetable and daily driver - a SR can work in the later category, but will just be a bit more maintenence intensive. You will also need to watch your spring pressure, etc. as I have seen quite a few SR street setups have issues with breaking lifters - strangely enough, the com's seem to be the worst about this - both the base and the endureX. Individual who broke both of those is currently running some of the GenVII's and they seem to be fine (for much longer than the other two together managed) - but then they are some 1k+ lifters, so they better last


Chris

 

You want the "Doc" cam back, or are you cookin up something new?