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By the way I too am a Mechanical Engineer.
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Rev Kits
Here is one I found real quick |
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I am sure it would just require a different spring, ....should'nt be too hard to find. The same manufacturer would probably be able to supply it.
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I haven't seen any.
The reason is probably because it's such a tight fit on a 302 block. You can't even pull roller lifters out without jerking the heads off first. You'll see different opinions about rev kits as a lot of builders don't use them. What is important for a high revving solid roller is adequate spring pressure and I start using stud girdles or shaft rockers starting around the 7000-7500 mark. Spinning an engine to 8000 rpm takes more than what most people realize. Making power at 8000 takes a LOT more head and cam than what most people realize as well. I wouldn't recommend a solid roller for the OP. I think it would be more expense and maintenance than necessary for what he's looking to do. |
I agree ,for most purposes a nice hydaulic roller cam in a 302 is more than adequate.Like I said 350 hp in a Cobra is plentyfor most applications.
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350 is plenty, 600 is perfect.
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Yes and even the OP's desire for 7000+ with power would be much better served with modern AFR's or similar with shafts or stud girdles and stiff springs-not a rev kit. And certainly not iron heads unless Brzezinski has a killer head design. Since he said top speed unimportant, at least a 3.54:1 or steeper would give him the zing he wants with such a combo. |
I agree Chas....a super high revver coupled with a 3.07 just doesn't allow for much fun.
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Forgot to mention; with steep gears, about a 16 pound flywheel would work wonders.
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BY the way check outthe dyno charts on this link........
Air Flow Research |
AFR makes very reputable products and I use their heads in almost all of my SBF stuff.
However, dyno tests can be manipulated to show whatever results you want. I personally don't buy into the rev kit hype, but if you take a head with inadequate spring pressure to start with, anything over that is going to show results. You can also gain 75-100 horsepower by using different valve springs. Seen it in person on my own engines. Just because you don't hear the stutter from a floating valve doesn't mean you're not losing control of the valvetrain. |
-and again, not for the 8.7 SBF the OP desires.
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The point is with the rev kit one does not need excessive spring pressure at the valve,which then is redirected down the pushrod to the lifter, creating a lot of pressure on all the inline components. Just as you said with the retainers and clips from Edelbrock, If all that they are controlling is the valve ,there is no lifter bouncing against a rising valve causing the locks to come loose. So I get the shafts and girdles... but that is overkill again. The rev kit ,Yes, was primarily for race only engines, but when one looks at the whole picture I think the benefits are many. I can tell you that with the mechanical lifters (rollers) that I have, I can hear that the only play is at the rocker( also rollers), at which a little play is absolutely needed, unless you run hydraulic, at which point without the rev kit the lifters and cam still are going to take more of a beating than with the kit. Hey ...what can I say ...I think the rev kit works great!!!:3DSMILE:
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Everyone has their own opinions.... ;)
But a rev kit without sufficient valve spring is going to cause just as much damage. I'm not aware of any Edelbrock head (maybe a Vic Jr) that comes setup for a solid roller camshaft. The standard spring pressure is sufficient for a flat tappet or a lazy hydraulic roller, but is not anywhere close to what's needed for a high revving solid roller. The rev kit is not helping you there. Some race applications dictate the need for 700-850 lb open pressures to spin high rpms efficiently. If you think you can get away with a rev kit and 300 lb springs, then so be it..... My comment about the retainers and locks was because they use pretty standard issue 7° stuff. Not Super 7 stuff and not 10° stuff. I personally don't feel that is sufficient, especially for 8000 rpm jaunts. |
BTW, Chas was trying to keep us on course, but I feel that we may be drifting a little from the OP's initial post. If you want to start another thread on rev kits, then that's cool.
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Would be nice to see if the OP is getting any value out of the great points you two are debating. I think it's all beneficial to what he's asking-don't stop now.
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Value? Yes, please keep it coming. I have plenty of time on my hands before I will need to settle on a balance of what I need/want/is achievable/can afford. So if 350hp is plenty, Brent, and 600 is perfect - and I know there's a little bit of tongue-in-cheek there - maybe I'm being misinterpreted there? When I say needs zing at high revs, does that translate to needs stacks of power at high revs? That's not what I need. I don't want to bend or break anything, including me, and 350hp in a light car sounds about right. Gearbox will be a wide ratio Toploader, so no overdrive and in conjunction with a 3.07 rear, should be OK for open road work. First gear from memory is 2.82, so will need a little clutch slip to move off, but then a decent turn of speed. I don't want or need a stump-puller first gear. And I'm not chasing blinding standing start times. More later. Thanks again for your interest and comments Cheers, Glen |
Yes, it was a little tongue in cheek. However, I see a lot of guys on here who have built an engine or bought a car, and in about a year's time, they're already asking what they can do for more power. The truth is that you get used to the car and you end up wanting a little more....
I'll stand by my recommendation of an engine (preferrably a stroked 302 if you want to stay with the traditional 8.200" deck height) that's cammed to make peak at around 5500-6000. Not going to a lower rearend gear will limit you on how much high rpm horsepower you can effectively use. If you build a car that's predominantly street driven, then you need to build an engine that will suit that lifestyle. Having an engine with a 7000 rpm peak only means that it will take it an extremely long time (relatively speaking and even more exaggerated with the 3.07 gear) to get into the powerband (what we call "getting up on the cam"). Up until that point, the engine will feel basically downright lethargic. Also keep in mind that an engine with more torque (comparatively speaking) will feel stronger to you (translate, seat of the pants, shove you in the seat) than a high-strung engine with a lot of horsepower in a high, narrow powerband and no power (and torque) down low. |
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