[mach1deamon]

ok,after my cousin kept telling me to go with roller rockers i decided to go with it(i have to decide which ones to go with). so im thinking of replacing my stock valves while im at it. the ones im looking at are described as: 1.655" EXHAUST AND 2.041" INTAKE STREET SERIES HEAVY DUTY VALVES FOR 351C 351M 400 FORD - BOTH INT. AND EXH. ARE 11/32 STEM 4-GROOVE.
EXH. VALVES ARE STAINLESS STEEL 21-2N - 5.052" LENGTH. INTAKE VALVES ARE HI-TEMP STAINLESS & S.I.L. MATERIAL - WILL WITHSTAND 1600 DEGREES! OVERALL LENGTH 5.230".

what do you guys think? are these good to replace stock valves? will i have to replace anything else?

 

[MightyMach]

I like my Harland Sharpes. they were the cheapest 1.73 ratio rocker. I have heard that you are not gonna feel a differance in power with just the R.R. swap. How high do you rev the motor to? You may not even need them. Anyone else' take?

Jeff Given

 

[mach1deamon]

the only reason my cousin convinced me was becouse he pointed out the reported 15-30 hp gain with roller rockers. but now im getting curious....anybody got some further info on the subject? what about the valves? good idea? about reving the engine, i mostly just drive it once in a while and i dont really race it at the track. but i want it to have some balls when needed

and a decent time in the 1/4 mile(like a low 14).

 

[ausTOM]

If you frequently see over 6000 revs you will want to go with single groove valves. I have seen a lot of stripped grooves on multi grooved valves that have had a hard time.

 

[MightyMach]

what is all done to the motor? Let us know...maybe there will be a better way to spend your 210 Dollars.

Again....curious, how high are you revving your motor?

Jeff Given

 

[mach1deamon]

first, thanks for your help. ok as far as the motor, it has stock 2v heads with headers. a holley 750 vac.secondary carb sits on a holley street dominator intake. internal is mostly stock exept for a 268 comp cam i bought to replace the crane energizer it had. minor changes include a replaced stock fan with an electrical fan, the orginal coil replaced by a MSD "blaster 2". the exhaust includes dual 3 inch pipe with flowmaster mufflers. thats all i can think of,im trying to give you guys as much info as i can so if i forgot something let me now.
as far as reving the motor, i dont really know what you mean. i think your talking about the revolutions i go up to before i shift gears(right)? if so, i dot have an answer for you now becouse my rpm tach doesnt work and i bought one thats going to be installed next week(sorry should have mentioned it). im planning on shifting gears at about 5000-5300 rpms though,thats the plan now.

 

[1970coupe]

Dont cheap out on your 351c valves. I learned the hard way last year and lost my complete motor. Buy single groove,one piece valves(this is important) from a reputable company.
Brian

 

[mach1deamon]

im leraning more and more guys, i wasnt aware of the single and multi groves on the valves. this topic is not over for me yet, like i said im trying to run a decent time at the track(like a low 14)

 

[futurattraction]

If you're going to get into working your heads, you should go the single groove, stainless valve route. I've not personally experienced valve problems but I've read numerous instances of the factory 4-groove valves failing. There are bolt-down roller rockers (Ford Racing among them) available for mild/moderate aplications that won't require getting your heads machined for an adjustable valvetrain, which really isn't necessary, if you get the bolt-down type adjusted correctly. There are also rocker arm conversions that are on the market (Crane). At the very least, if you kept your stock rockers, you should get replacement 4V steel fulcrums/rockers to replace the aluminum fulcrums that came from the factory on your 2V heads (assuming they haven't been replaced). Another site you might be interested in looking at is the 335 Cleveland site (Boss 302, 351C, 400, Aussie 302, etc.).

http://www.network54.com/Hide/Forum/119419

Best wishes.
Scott

 

[mach1deamon]

thanks for the info. so what do you think mightymach?

 

[mach1deamon]

what do you guys think about the 1/4 mile time im shooting for?