Hi all... Looking for opinions. About to begin a 302DZ buildup. Obviously the 30-30 mechanical is the correct stick to use, but a hydraulic, or maybe even a hydraulic roller might be good to avoid valve adjustments. My fear is that a 302 needs to wind up tight in order to make power, and a hydraulic,even if a roller, may not be able to buzz to 7k plus like the good old mechanical. I'm sort of thinking out loud, but would appreciate other thoughts and ideas. I've even toyed with the idea of a mechanical roller. Goal is an honest 400 HP at the flywheel. It will be a weekend driver, not a trailer queen.

Thanks!:thumbsup:

Hey BelAir,

I'm thinking you'd want to stick with the solid or solid roller, because as you have already hinted to, you need to wrap these little motors up to make them cook. So I don't think you'll be tapping into all of the motor's potential if you go hydraulic. Just my thoughts at least.

Hi all... Looking for opinions. About to begin a 302DZ buildup. Obviously the 30-30 mechanical is the correct stick to use, but a hydraulic, or maybe even a hydraulic roller might be good to avoid valve adjustments. My fear is that a 302 needs to wind up tight in order to make power, and a hydraulic,even if a roller, may not be able to buzz to 7k plus like the good old mechanical. I'm sort of thinking out loud, but would appreciate other thoughts and ideas. I've even toyed with the idea of a mechanical roller. Goal is an honest 400 HP at the flywheel. It will be a weekend driver, not a trailer queen.

i'd go with solid roller and a set of shubeck lifters that's the key to 400+ fwhp in a dz302. adjusting valve lash sucks but it's a small price to pay in order to have a high horsepower 302. if it's a weekend driver you'll probably only need to adjust them once or twice a year, not a big deal really.

Hi all... Looking for opinions. About to begin a 302DZ buildup. Obviously the 30-30 mechanical is the correct stick to use, but a hydraulic, or maybe even a hydraulic roller might be good to avoid valve adjustments. My fear is that a 302 needs to wind up tight in order to make power, and a hydraulic,even if a roller, may not be able to buzz to 7k plus like the good old mechanical. I'm sort of thinking out loud, but would appreciate other thoughts and ideas. I've even toyed with the idea of a mechanical roller. Goal is an honest 400 HP at the flywheel. It will be a weekend driver, not a trailer queen.

Thanks!:thumbsup:
I would go with the original solid cam and enjoy it. Top end will be a lot better with it.
Also, I drove mine alot and only needed to adjust the valves once a year.
Schoon

Please do a search here b/c we periodically beat this to death!

AND I personally love the little high-strung buggers myself!!

I have a real big soft-spot in my heart for the little short stroke motors that you can wind up until your Buddy looks over and ask's you, "When are you gonna shift the sucker??"....

I'm gathering parts now for either a 292 or a 301 myself just for the fun of it. I'm gonna shift it above 8,000 rpm!!

pdq67

PS., and it's gonna be old-school "shade-tree" all the way just like my first one was that had the great little old Duntov -097 solid cam in it!!

Why build a 302? Valve adjustments are 10k mile maintenance, or more often for the hobbyist.

Huh?

Way back when lots of people swapped the '346' mechanical for the '151' hydraulic cam used in the L79 350/327. It was engineered for an 11:1 motor and will buzz to 6500 no problem.

400 hp and 7000+rpm is asking a lot from a "streetable" 302. Todays' NHRA stock class 302s dyno around 425hp with a non-stock cam and race-only blueprinting. Stock heads max out around 6500 rpm but lots of guys wound them past that. In stock form more rpm does not=more power, the main reason so many 302s ended up with spun bearings and scuffed pistons.

Refer to the MCR 302 build up done almost 20 years ago: 326 hp@6400.

Huh?

Way back when lots of people swapped the '346' mechanical for the '151' hydraulic cam used in the L79 350/327. It was engineered for an 11:1 motor and will buzz to 6500 no problem.

400 hp and 7000+rpm is asking a lot from a "streetable" 302. Todays' NHRA stock class 302s dyno around 425hp with a non-stock cam and race-only blueprinting. Stock heads max out around 6500 rpm but lots of guys wound them past that. In stock form more rpm does not=more power, the main reason so many 302s ended up with spun bearings and scuffed pistons.

Refer to the MCR 302 build up done almost 20 years ago: 326 hp@6400.
Thanks for your opinions guys. I'm leaning more towards mechanical roller that is slightly hotter than the 30-30 cam, at about .504 lift and 247/254 duration at ".050". Should be good to 7K, and pick up some HP due to frictional losses. It also runs a much tighter lash of .012, as opposed to the "real" .026 of the 30-30, so less clacking, and probably more power.I'll also "pocket port" the heads , and back cut the valves for better flow,which should really wake things up. The famous (or infamous) Desktop Dyno says the combo described should make 440HP @ 7200 with open headers and single plane manifold, 10.5 CR, 2.02, 1.6 valves, 780 carb. I may go with a Z/28 intake though, since I'd like to try to keep a more original look. William, which buildup is the "MCR"?

That was the Sep '87 issue "Planning For Performance". Same issue with the famous Jim Luikens interview, parts guy at Berger Chev in the day.

Since I had to dig it out actual numbers were 327hp@6750 with '346' cam; 347hp with the '140' cam. But the dyno photos show headers, no alternator, fan or air cleaner. Plus it had aftermarket pistons and had been honed with a torque plate.

we're going down to maryland within the next few weeks to pick up an engine that was built by jerry mcneish. it was dyno tuned to ~425 horse and I believe the peak power was made at 6800 rpm. he said with a different cam the engine could have put out another 40-50 horse but would have been totally UN-streetable. can't wait to hear this run - I'll take a video and post it when I can. probably a couple mos away.

How do I attach a media file? I've got a great dyno run of a screamin' 302!

I think Tony's little 302 motor made 465 hp on the dyno before he found out it had a bad cylinder..

Do a search here b/c the info is here...

pdq67

Jerry is Da Man!

No one knows 1st gens better or loves them more. In a hobby rapidly being taken over by poseurs and fast-buck artists he hasn't changed one bit in the 15 years of our acquiantance.