Well, yes you could, but seeing as you can buy good second hand B303's for about $60, and a set of used cobra rockers for $100, why would you ? Roller cams rarely wear out. And those Cobra roller rockers ? I've had a set I bought used for $125 with 100K miles on em ten years ago that show no signs of wearing out. You'll get more benefits from the roller rockers than just the increased ratio (1.6 to 1.7) alone. Cooler oil temps, decreased friction from the swich to roller trunions over the sled fulcrums are benefits you won't get from a different cam grind. Oh, and there are no dumb questions. Ask away. You may get a few dumb answers though.:-X04

Where do you suggest we purchase a set of used roller rockers? Ebay, craigslist??

Can we use the same set of pushrods or will we need to purchase a different set?

Thanks again for all the information.

Buy em where you find em. Haven't looked for any lately, so I couldn't tell you where. Or buy a new set of Crane Energizer pedestal 1.7's. These are the same rockers as the Cobra's, which were made for Ford by Crane. Use the same pushrods,(6.25" for a roller 5.0) but I would replace these as the roller pushrods do not spin in service(cause the lifters don't spin) and tend to wear to a somewhat knife edge on the rocker ends after 100K miles. I tend to shop around when I can, I never had an unlimited budget for anything related to this, there are always good deals to be had for those who have the time to do a little parts hunting.

Cobra rocker arms
 

I bought a set of the "Cobra" pedestal mount roller rocker arms a couple years ago from eBay. Although they were okay, several of the pedestals were cracked, presumably from someone tightening down the 5/16" Allen head cap screws way too tight. The pedestals also varied in working height by up to .020". Luckily I was able to order a new set of 16 pedestals for less than $20.

I was still pleased with my purchase, but learnt that one must be vigilant when dealing with used parts as people will cause the strangest damage to parts.
:-drink

It's a wonder they didn't twist the bolts off. 25 ft/lbs is all they need.

You want to be careful adding 1.7 rockers to a high lift cam, coil bind sets in at a little over 0.500", and besides that E7TE and GT40 heads stop increasing airflow at about 0.500" lift so pushing the valvetrain past this point isn't really buying you anything. On heads that have been ported to flow at higher lifts aftermarket springs are required but they aren't just a simple bolt-on either, the springs seats often have to be cut to get the proper installed height and sometimes the valve guide bosses have to me machined down to make room for seals inside these double spring sets. IMO if you select a cam with anywhere close to 0.500" lift you're getting 95% of the heads potential and it's not worth the extra cost to get those last few ponies.

The gt40(p) head, B cam and 1.7 cobra rocker are a time proven combination. Ford Motorsport sells a matching spring set that is recommended to accommodate the other parts.

go to jegs and look at comp cams thumper cam.




it designed for what your trying to do.

The 1.7's work fine with a B303 on stock E6 and E7 heads and springs. . No coil bind.