427 SBF

Low & slow said:
D

Did he say why the cam was done at 7000 rpm , lack of duration? Or intake valve closing to soon ?
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The other cam was a custom comp cam, all they did was add 10° to a crane cam I was using, lol.
268/276 @ 050, only 636 lift (comp cam)
Heads and intake hadn't been ported either.
 
BOSS#1540 said:
Yes, set up to shift at 8200 and cross at 8600. It doesn't have much more duration and about the same overlap as the cam I was running, which was supposed to be 4-8000rpm but was done at 7000. Old one was 108 lsa, +4 , NEW ONE is 112/113 lsa +4
I talked with mike lots, he's very helpful, but I'll leave that stuff up to him, lol.
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He's a pretty smart guy.
A few years ago he posted a great description of how to calculate the .050 difference between a solid and hydraulic cam.

Which, if I remember correctly, was exactly the opposite of what Vizard said. :LOL:
 
BOSS#1540 said:
Figure 8's on some fine grit on a flat hard surface and see it's contacting everywhere or has a high spot. Check both sides.
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We had to make sure heatsinks were flat in a product we made for years. Had a piece of glass with 220 grit sand paper glued to it and did figure-8's with each one. Amazing how warped they got after machine work. Didn't take long to flatten them, just a few thou. The sandpaper lasted a very long time. Glass is always flat, not all surfaces are.
 
Patriot Racer said:
No MUTE warning?
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His version of a Rick Roll! :)
89 Fox 427 said:
23 at .050 is correct
76 at advertised

I still don't understand the 113lsa in my combo
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The wider LSA typically gives a smoother idle with more vacuum, and is usually better up at high rpm. I don't totally understand that, but if you look at NHRA Prostock stuff, they use a very wide LSA.

Get a new lifter from Amazon and take it apart and stack washers and crap in there to make a solid lifter out of it. I did that with a pair of old lifters so it didn't cost me anything.

On hydraulic rollers I let them soak in oil overnight at a minimum then do the oil can into the side hole. It's messy, but at least they are coated in oil and ready to drop-in.
 
Finally took the wifeys engine fully apart, This piston was HAMMERED! Three were broken, this one the worst. Phucking thing was still running good, but she said it was running about 10* more than she was used to when she entered the burnout box, and I had to adjust the idle screw to bring it up to where she liked it.

Idle screw = viagra? Maybe............ :)

Anyway, be careful with timing and compression on pump gas! I cc'd the heads and the calculator shows we were around 11.5:1 compression. The amount of damage really surprises me. There is over an inch of top ring GONE! All those aluminum pieces of piston and hard steel rings left that engine without ever touching a spark plug! The added heat came from this cylinder, that top ring is seized, the rest of the rings in the engine were still rotating freely.

odZCv8g.jpg
 
89 Fox 427 said:
The rest of you ballers would have paid for next day air.

My broke ass had to settle for 2nd day
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Wider lsa has less overlap, filling your cylinder better at low rpm vs high rpm, maybe, lol. Volumetric efficiency? Scavenging has a lot to do with filling your cylinder also. Cylinder head efficiency.
My 414 in the bronco has a hyd roller from howards and it's 112 lsa @ +4 and it was all about low end tq.

Was this cam matched to your previous heads/combo ?
 
Mike Beck said:
Finally took the wifeys engine fully apart, This piston was HAMMERED! Three were broken, this one the worst. Phucking thing was still running good, but she said it was running about 10* more than she was used to when she entered the burnout box, and I had to adjust the idle screw to bring it up to where she liked it.

Idle screw = viagra? Maybe............ :)

Anyway, be careful with timing and compression on pump gas! I cc'd the heads and the calculator shows we were around 11.5:1 compression. The amount of damage really surprises me. There is over an inch of top ring GONE! All those aluminum pieces of piston and hard steel rings left that engine without ever touching a spark plug! The added heat came from this cylinder, that top ring is seized, the rest of the rings in the engine were still rotating freely.

odZCv8g.jpg
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Pfft, 11.5:1 😆🤣😭😉, try 12.8:1, lol.

I did the same, lifted a ring land from a lean carb on longest runner #1, piece closed plug gap so instant miss. 2nd time didn't even know, ran fine, lots of power and still 185psi (should be 220) 😆. Took head off and said holy fuck, the top of my piston is gone 😳

Edit: that was with 31° and Cleveland 🤮 quench chambers. Quite a bit involved to run high cr on pump 93
 
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BOSS#1540 said:
My 414 in the bronco has a hyd roller from howards and it's 112 lsa @ +4 and it was all about low end tq.

Was this cam matched to your previous heads/combo ?
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It was matched to the new combo. Though my request was I wanted a rough idle you could hear from across the intersection. I sure don't need top end power here. Average tq across the curve is really what's important. Not concerned about it falling on its face up top

The cam in the video sounds almost as terrible as the surge in a blower car, fuck that.
 
89 Fox 427 said:
It was matched to the new combo. Though my request was I wanted a rough idle you could hear from across the intersection. I sure don't need top end power here. Average tq across the curve is really what's important. Not concerned about it falling on its face up top

The cam in the video sounds almost as terrible as the surge in a blower car, fuck that.
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So you want a smooth lumpy idle 😉
 
Mike Beck said:
We had to make sure heatsinks were flat in a product we made for years. Had a piece of glass with 220 grit sand paper glued to it and did figure-8's with each one. Amazing how warped they got after machine work. Didn't take long to flatten them, just a few thou. The sandpaper lasted a very long time. Glass is always flat, not all surfaces are.
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I use a freshly ground flywheel for that stuff, with sandpaper glued like you do.
 
Mike Beck said:
The wider LSA typically gives a smoother idle with more vacuum, and is usually better up at high rpm.
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Well who the fuck wants that? 🤣

Maybe I need to continue to watch more videos but I have yet to see a dyno video or test where going tighter lsa lost power in the midrange until they went really tight, like 104 tight
 
Your cam is pretty big for a street cam, you might have enough overlap to get a lopey idle.

Take a look at the overlap of one of the medium size Thumpr cams (~230 intake) and see how the overlap compares to yours.
 
I want to say, if I haven't already.. I trust that this cam is going to be great for my setup. I just find the numbers to be strange in comparison to the other suggestions I came across
 
You know what they say about opinions........

They are like assholes, everyone has one! Well, most everyone......... Opinions yes, butt holes, not always.........

I think you would like a 110 LSA for what you are doing. But if you already paid for a cam and have it in your hands, STICK IT IN! :)

Try it and see how you like the combo. I have worked on NHRA Stock Eliminator cars, they have a crazy narrow LSA to make them move, they have NO top end! Their stock heads/intake/carbs/throttle bodies are so restrictive they have to make everything they can by the 330ft, after that there isn't much happening.

The EFI A & B Stockers I tune will go to 7500, but they also S T R E T C H the rules a wee bit.......... I can't talk about it, it's like Vegas, what happens there stays there. I just tune the engines I am given, I pass no judgement on how they get them to do what they do. ;)
 
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