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  #16 (permalink)  
Old 12-20-2012, 05:17 PM
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rawr? Dont run him off right when hes about to help me lol.

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  #17 (permalink)  
Old 12-20-2012, 05:27 PM
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Quote:
Originally Posted by F-BIRD'88 View Post
Its real simple. The dynamic compression ratio is based on simplictic intake valve closing point.
When for 1 is very hard to accuratily establish.
I call BS. The mfg will give you the intake closing point down to minutes and seconds if you ask for it and it's not that difficult for a home garage builder to find 1 degree.

Quote:
Originally Posted by F-BIRD'88 View Post
2. the RUNNING engine's real in cylinder pressure has nothing to do with the cranking compression.
when its running at speed.
I call BS. Show your scientific data to support that statement.

Quote:
Originally Posted by F-BIRD'88 View Post
In the real world, engines do not operate in a tightly controled environment.
Gas quality changes, operating temps change, air inlet temp changes widely.
The knock tolerance of a engines varies widely based on the actual operating conditions at any one time.
I call BS. What are you going to do, reach out into thin air and pick a cam?

Quote:
Originally Posted by F-BIRD'88 View Post
As a general statement engines that operate in the real world with more than 10.5:1cr that are not computer electronic controled will be knock sensitive on even good pump gas reguardless of the cam used.
When things get hot they get hot.
I call BS. What data do you have to back up what you say?

Quote:
Originally Posted by F-BIRD'88 View Post
For every internet guru that claims that you can do this and that there are 4 guy who found out how the real world really works.
You don;t pick a cam based on simple dynamic compression ( theory).
I call BS. Where's your data to prove what you're saying?

Quote:
Originally Posted by F-BIRD'88 View Post
You cannot predict the cranking compression based on published cam specs.
These are not the true running open close specs of a RUNNING engine.
I call BS. Where's your data?


Quote:
Originally Posted by F-BIRD'88 View Post
Your cam picks are always lame and wrong fo both power and .....
I call BS. Sounds like one punk's opinion to me.

[quote=F-BIRD'88;1625176]
Your power estimate are always wrong and lame based on over simplistic $20 computer programs and wrong inputs./[QUOTE]

I call BS. Sounds like one punk's opinion to me.

Quote:
Originally Posted by F-BIRD'88 View Post
In short you are full of BS,,,, SIR. have a nice day.
Again, BS. Just one punk's opinion.

That seems to be all you have is opinions with nothing scientific or mathematical to back them up. I call BS on your entire agenda.

Just for the record, I have PM'd you in the past and tried to make friends. My PM was never answered, leaving me to think that you are just a punk who is devoid of honor and integrity and chocked full of BS opinions.
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  #18 (permalink)  
Old 12-20-2012, 05:47 PM
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Originally Posted by 0trbo4myCHEVUICK View Post
rawr? Dont run him off right when hes about to help me lol.
Nobody is runnin' me off. Stay tuned.
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  #19 (permalink)  
Old 12-20-2012, 05:48 PM
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Originally Posted by F-BIRD'88 View Post
I have enough friends... thanks.... I don't try to be popular.. Just here to help a few, who ask,, based on the real world and
how it really works.
Then back up what you say with science and math and quit raggin' on my stuff.
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  #20 (permalink)  
Old 12-20-2012, 05:54 PM
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I see a lot of new cars with 12:1 CR and mazda uses 14:1 for both gas and diesel economy engines.None of those cars are running lumpy cams? BMW has a lot of 11:1 and higher engines.
Maybe tech is not that far off? He uses friendly and conservative numbers.
I like to debate with him.
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  #21 (permalink)  
Old 12-20-2012, 06:01 PM
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Originally Posted by F-BIRD'88 View Post
Here is some data for your that pretty much matches what happens in the real world.
Daytona Sensors LLC - Tech FAQ Engine Tuning
Thank you for the article. I read it. While it addresses air fuel ratio and spark timing, it stops short of explaining what camshaft timing needs to be used to complement the max 10.5:1 static compression ratio. Could a guy supposedly use any cam he feels like using? That's what the article suggests. In other words, you could use a cam that closes the intake valve at 20 degrees and have the same results as another cam that closes the intake valve at 60 degrees. I call BS. If that's your "real world", I call double BS with sprinkles.
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  #22 (permalink)  
Old 12-20-2012, 06:07 PM
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Quote:
Originally Posted by F-BIRD'88 View Post
i don;t "rag on your stuff" I don't knock what your say reguarding DCR just cause I don;t like you. and I don't not like you.

But your advise based on this inaccurate over simplistic application of a over simplistic theory

Is what I like to call..... WRONG...
Not all the experts and engineers that I read call it wrong. You are the only person I see calling it wrong. I call BS. You have no data to support your opinion. Just keep raggin' on my stuff and I'll keep on raggin' on your stuff.
You are about to find me relentless because I'm now pizzed-off.
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  #23 (permalink)  
Old 12-20-2012, 06:16 PM
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OMG! I feel sorry for the poor car hop girl at the drive in that gets the combo wrong! wrong tomato:cheese ratio with the wrong amount of onion rings.Wont get enough quench with a small rootbeer.Have to watch the compression in order to get the bun at the correct installed height. The roller skate wheels are the wrong diameter causing poorly matched RPM for the distance to the kitchen.
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  #24 (permalink)  
Old 12-20-2012, 07:05 PM
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anybody have the capability to computer simulate the 355 vs 406 combos? I am curious just how much the theoretical numbers would differ and at what revs the action would happen at. So far only one guy has posted about an actual experience w/ a vortec headed 400.. and honestly its sounding pretty good to me. The rest have just said "no gains" or "less rpms than a 355" or "you need change everything" I need to know what 51 cubes would actually change.. when using MY stuff.. lose 500rpms? 1000 rpms? gain 15lbft? 40lbft? help me out here.

clearly there is some other unfinished off topic business goin on here..
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  #25 (permalink)  
Old 12-20-2012, 07:37 PM
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350 vs 400. With the 400, you are looking at an extra 40lb. ft of torque and an extra 40 horsepower, with the same cam as the 350, all of which will occur lower in the RPM range. You can also cam up a step or 2 with the 400 which will handle a larger cam. Peak Hp will be 400-500 rpm lower in the 400. Torque will be good right from idle with the 400. A 350 has to rev up to 2500 to start making good torque. 1 3/4 headers are good for a 400. 1 5/8 headers are probably better suited to a 350 street motor 400 hp or less. 3 in exhaust is a little large. for the 350. 2 1/2 may give better torque on the 350. 3 in exhaust may work fine with the 400.

It is all about hte combination of parts working together. larger exhaust is good for high rpm power - all out racing. smaller headers and exhaust work better for a street driven car. I hope this is helpful.
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  #26 (permalink)  
Old 12-20-2012, 07:48 PM
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Quote:
Originally Posted by cr480r View Post
anybody have the capability to computer simulate the 355 vs 406 combos? I am curious just how much the theoretical numbers would differ and at what revs the action would happen at. So far only one guy has posted about an actual experience w/ a vortec headed 400.. and honestly its sounding pretty good to me. The rest have just said "no gains" or "less rpms than a 355" or "you need change everything" I need to know what 51 cubes would actually change.. when using MY stuff.. lose 500rpms? 1000 rpms? gain 15lbft? 40lbft? help me out here.
clearly there is some other unfinished off topic business goin on here..
OK, this is just my opinion.
L31 heads, as good as they are, are still heads that were designed by engineers to feed a 350 cubic inch engine up to about 5000 rpm's. 350 cubic inches theoretically passes 506 cfm @5000 rpm's. 400 cubic inches theoretically passes 509 cfm @4400 rpm's. So, you might make the argument that the L31 heads on a 400 are theoretically done at 4400 and could stall at rpm's over that.

I'm aware that other members of this board will suggest that L31 heads will make power to XXXX rpm's and that's fine. I'm just trying to make some sense to the OP.
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  #27 (permalink)  
Old 12-20-2012, 07:51 PM
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Quote:
Originally Posted by vinniekq2 View Post
OMG! I feel sorry for the poor car hop girl at the drive in that gets the combo wrong! wrong tomato:cheese ratio with the wrong amount of onion rings.Wont get enough quench with a small rootbeer.Have to watch the compression in order to get the bun at the correct installed height. The roller skate wheels are the wrong diameter causing poorly matched RPM for the distance to the kitchen.
Thanks Vinnie, LMAO.
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  #28 (permalink)  
Old 12-20-2012, 07:55 PM
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Quote:
Originally Posted by cadillacdave1 View Post
350 vs 400. With the 400, you are looking at an extra 40lb. ft of torque and an extra 40 horsepower, with the same cam as the 350, all of which will occur lower in the RPM range. You can also cam up a step or 2 with the 400 which will handle a larger cam. Peak Hp will be 400-500 rpm lower in the 400.
even if there was zero HP gain, and I gained 40 lbsft at launch rpms... thats worthwhile IMO..
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  #29 (permalink)  
Old 12-20-2012, 08:03 PM
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Quote:
Originally Posted by techinspector1 View Post
OK, this is just my opinion.
L31 heads, as good as they are, are still heads that were designed by engineers to feed a 350 cubic inch engine up to about 5000 rpm's. 350 cubic inches theoretically passes 506 cfm @5000 rpm's. 400 cubic inches theoretically passes 509 cfm @4400 rpm's. So, you might make the argument that the L31 heads on a 400 are theoretically done at 4400 and could stall at rpm's over that.

even with a tiny 216 duration cam all my vortec 350's pulled well past 5000. the 230 duration combo would pull my lifted fullsize 4x4 truck to 5900rpms in fourth gear.. In my expereince they easily support 6500rpm shift points on a well cammed 355. So if a 400 would peak 5500 and hang on til 6000 thats plenty for me if it charges out of the hole harder..
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  #30 (permalink)  
Old 12-20-2012, 08:13 PM
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Quote:
Originally Posted by cr480r View Post
even with a tiny 216 duration cam all my vortec 350's pulled well past 5000. the 230 duration combo would pull my lifted fullsize 4x4 truck to 5900rpms in fourth gear.. In my expereince they easily support 6500rpm shift points on a well cammed 355. So if a 400 would peak 5500 and hang on til 6000 thats plenty for me if it charges out of the hole harder..
Just because it revs to an RPM does NOT mean it makes power there. A lot of people think that just because they can "feel it pull" at a certain RPM then it must be making big power. That's part of the reason everyone that owns a sbc with an aftermarket muffler is making 500+hp, they just hope and wish and think about the power until it's magically there.
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