427 SBF

89 Fox 427 said:
Also, I have already had to cut my carb vent tubes because the drop base caused the top of the air cleaner to hit them
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Badd_Dadd said:
Well that's a fuck up
Click to expand...
  • Rich Fuel Mixture:
    When the vent tubes are blocked or too short, the float bowl can't properly vent air as fuel flows in. This leads to a buildup of pressure, forcing fuel into the engine even when it's not needed, resulting in a rich fuel mixture.

  • Fuel Flooding:
    The increased pressure in the float bowl can cause fuel to overflow into the engine, potentially causing it to stall or be difficult to start.

  • Vapor Lock:
    In some cases, the increased pressure and lack of venting can also lead to vapor lock, where fuel boils and forms vapor bubbles, disrupting fuel delivery and causing engine issues.

  • Poor Engine Performance:
    The overall effect can be a poorly running engine, with issues like hesitation, stalling, and rough idle.
In short, the vent tubes are crucial for maintaining the correct pressure balance within the float bowl and preventing fuel from being overfilled or forced into the engine prematurely.
 
Patriot Racer said:
  • Rich Fuel Mixture:
    When the vent tubes are blocked or too short, the float bowl can't properly vent air as fuel flows in. This leads to a buildup of pressure, forcing fuel into the engine even when it's not needed, resulting in a rich fuel mixture.

  • Fuel Flooding:
    The increased pressure in the float bowl can cause fuel to overflow into the engine, potentially causing it to stall or be difficult to start.

  • Vapor Lock:
    In some cases, the increased pressure and lack of venting can also lead to vapor lock, where fuel boils and forms vapor bubbles, disrupting fuel delivery and causing engine issues.

  • Poor Engine Performance:
    The overall effect can be a poorly running engine, with issues like hesitation, stalling, and rough idle.
In short, the vent tubes are crucial for maintaining the correct pressure balance within the float bowl and preventing fuel from being overfilled or forced into the engine prematurely.
Click to expand...

I now (eventually) will have them tied together like Dom posted in another thread
 
Steve439 said:
Yeah, I'd like to run something better but I have no room.
I had cut my vent tubes too.
Straight across with a pipe cutter... :banana:

Some of this stuff doesn't agree with what is intuitive.
The air cleaner on tri-power Corvettes has about half the filtering area of the normal 14x3.
I wondered for years if that's what caused the 15 HP drop when they put tri-power on the '67 vs '66.

Nope, a guy I trust on the Chevelle forum dynoed a tri-power motor with and without the air cleaner.
The HP loss wasn't worth worrying about.

It would be really interesting to see if using a single plane and reducing the height of the element to fit gains HP.

That combo Brian posted a bit above looks to be .7 higher than a Performer RPM.
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Id assume exhaust ports aren't in stock location.

I find it odd that most heads that size are only good to .600 lift without upgrades. I guess I assumed people often ran more than .600 lift at that size head but clearly I'm wrong
 
89 Fox 427 said:
Id assume exhaust ports aren't in stock location.

I find it odd that most heads that size are only good to .600 lift without upgrades. I guess I assumed people often ran more than .600 lift at that size head but clearly I'm wrong
Click to expand...
Never ever have I ever bought assembled heads.
Always build them to what the junk under em need
 
89 Fox 427 said:
Id assume exhaust ports aren't in stock location.

I find it odd that most heads that size are only good to .600 lift without upgrades. I guess I assumed people often ran more than .600 lift at that size head but clearly I'm wrong
Click to expand...

Wow whee, I googled it, It looks like it has stock exhaust ports:

Intake Port Location:
Standard
Exhaust Port Shape:
Square
Exhaust Port Location:
Standard
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www.trickflow.com

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Free Shipping - Trick Flow® Twisted Wedge® 11R 227 Cylinder Heads for Small Block Ford with qualifying orders of $109. Shop Cylinder Heads at Trick Flow Specialties.
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You can call me a pup, but both of my cams are right about .600 net.

I don't need the extra horsepower for the street and I love reliability.
 
Briansshop said:
I've bought/run assembled AFR and TFS heads many times. Sometimes need a spring change only. Have a set of the TFS 11R 227s,just waiting on the short block assy.
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You don't ever run anything n/a. You got a build thread here for it?
 
Here are the cam specs I have in my 10.5:1 406 SBC, runs on Super Unleaded, goes 10.5 @ 128 @ 3400lbs.
.679/.630
278/286
108 LSA

That is with 1.5 rockers. Idles smoothly at 1000, can probably idle at 800 or so if I wanted to, but it is in a race car now so no need. We slow it down for 11.50 Index Racing. Go through the traps at 7000 rpm (1/4 mile).
 
This is the cam in my 14.7:1 420 SBC. I shift around 7500, go through the traps at the same.
It has been to 8500 on nitrous and was perfectly happy! :)

.765/.731
266/277
107 LSA

Funny that this cam has less duration than my other engine.
Idles beautifully at 1000. I have been 9.4 @ 148 @ 3200 lbs with that car going 8200 through the traps.

Even though it has less duration, this thing is way snappier, way louder than the other engine. I guess it's the compression.

Both cars are muffled.

BTW: The first cam is an off the shelf cam from Lunati. The second cam is a custom grind I got through LSM. I have a friend that is good at designing cams, he did the one for my engine, I love it!
 
Mike Beck said:
Here are the cam specs I have in my 10.5:1 406 SBC, runs on Super Unleaded, goes 10.5 @ 128 @ 3400lbs.
.679/.630
278/286
108 LSA

That is with 1.5 rockers. Idles smoothly at 1000, can probably idle at 800 or so if I wanted to, but it is in a race car now so no need. We slow it down for 11.50
Click to expand...

Are those @.050 duration numbers? Take care. Tom Worthington
 
Tom396 said:
Are those @.050 duration numbers? Take care. Tom Worthington
Click to expand...
Yes. I don't even have the total duration numbers for the cam in my engine, it's not on the cam card.
In fact, the cam card from LSM is a joke. Nothing like a cam card from Comp, Lunati, or Bullet. I have used stuff from all of them.
 
Patriot Racer said:
  • Rich Fuel Mixture:
    When the vent tubes are blocked or too short, the float bowl can't properly vent air as fuel flows in. This leads to a buildup of pressure, forcing fuel into the engine even when it's not needed, resulting in a rich fuel mixture.

  • Fuel Flooding:
    The increased pressure in the float bowl can cause fuel to overflow into the engine, potentially causing it to stall or be difficult to start.

  • Vapor Lock:
    In some cases, the increased pressure and lack of venting can also lead to vapor lock, where fuel boils and forms vapor bubbles, disrupting fuel delivery and causing engine issues.

  • Poor Engine Performance:
    The overall effect can be a poorly running engine, with issues like hesitation, stalling, and rough idle.
In short, the vent tubes are crucial for maintaining the correct pressure balance within the float bowl and preventing fuel from being overfilled or forced into the engine prematurely.
Click to expand...
Was that you and I at barona where we had an issue with fuel sloshing out on the hit from the vent tubes? Maybe it was Richie.. been a while. Ran some 3/8 fuel line from vent to vent and cut a hole in the top of the arch.
 
Mike Beck said:
This is the cam in my 14.7:1 420 SBC. I shift around 7500, go through the traps at the same.
It has been to 8500 on nitrous and was perfectly happy! :)

.765/.731
266/277
107 LSA

Funny that this cam has less duration than my other engine.
Idles beautifully at 1000. I have been 9.4 @ 148 @ 3200 lbs with that car going 8200 through the traps.

Even though it has less duration, this thing is way snappier, way louder than the other engine. I guess it's the compression.

Both cars are muffled.

BTW: The first cam is an off the shelf cam from Lunati. The second cam is a custom grind I got through LSM. I have a friend that is good at designing cams, he did the one for my engine, I love it!
Click to expand...
My old 636 was 268/276 with 108 lsa in on 104 icl.
I think big heads and overlap make noise, lol. Guys at the dyno said it was the loudest engine they'd heard, buttering me up, lol.
New cam is 278/284°, 837 lift, 112°/113° lsa on 109 icl from jones.
 
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Hollow65 said:
Was that you and I at barona where we had an issue with fuel sloshing out on the hit from the vent tubes? Maybe it was Richie.. been a while. Ran some 3/8 fuel line from vent to vent and cut a hole in the top of the arch.
Click to expand...
It wasn’t me. I’ve never had that issue. I read a post on YB where a guy fixed that and picked up 2 tenths.
 
Mike Beck said:
Here are the cam specs I have in my 10.5:1 406 SBC, runs on Super Unleaded, goes 10.5 @ 128 @ 3400lbs.
.679/.630
278/286
108 LSA

That is with 1.5 rockers. Idles smoothly at 1000, can probably idle at 800 or so if I wanted to, but it is in a race car now so no need. We slow it down for 11.50 Index Racing. Go through the traps at 7000 rpm (1/4 mile).
Click to expand...

I would expect my really amazing cam guy to be more in the .629/.636 with 236/242 ish and maybe 108-110 for this boring little street car. My heads flow well but not amazing (promaxx 210cc/56cc) and i figure I'll never know the true hp number because I won't wind it up enough to know (and the dual plane will castrate the top end which I'm ok with). At least I can say it's got more in it.

I just made those cam numbers up to try and be part of the conversation, please refrain from shitting on me
 
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89 Fox 427 said:
I would expect my really amazing cam guy to be more in the .625/.630 with 234/242 ish and maybe 108-110 for this boring little street car. My heads flow well but not amazing (promaxx 210cc/56cc) and i figure I'll never know the true hp number because I won't wind it up enough to know (and the dual plane will castrate the top end which I'm ok with). At least I can say it's got more in it.

I just made those cam numbers up to try and be part of the conversation, please refrain from shitting on me
Click to expand...
There’s ALWAYS more in it! 😝
 
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