Nah,it's cool,I was just being more than slightly sarcastic (and just a bit cynical to boot),as both those things are well within my nature.
Cliff & I do this sorta thing from time to time,I dont take it seriously,doubt he does either.
Look,the compression ratio thing is'nt a deal breaker,that was just me throwing out a potential option to consider,as it seemed you were being more than a little hesitant to pull the trigger on the 6X's due to the stated CR you mentioned.
I figured the KB/Icon forgings might be just enough to help ease your fears a bit.
See I'm not rabid about things like CR,I may state my general thoughts/opinions,but I dont feel any subject is as "set in stone" as some others seem to feel they are.
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Originally Posted by Nicks67GTO
My initial plan was to go this route. 400ci, 290cfm Kauffman heads, 10.5:1 compression with a 236/244@.050, .550/.550 lift solid FT cam on a 110 ls {made up cam specs}. I figured that would get me around 500hp @ around 6000 RPM, 500tq around 4000 rpm with a fairly flat curve. I figured it would idle around 850rpm and run hard. From everything ive gathered here i was wrong.
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Yeah,first thing first that kinda solid cam would be waaayyy too small for that sorta deal.
It would take a solid cam up closer to 245° to 250° intake and 250° to 255° exhaust duration to have a chance in hell of making 500 hp from 400 cid engine like that.
And that's gonna have a fairly lumpy idle likely too.
That 400 cid combo would'nt make as much torque as the big inch 468 combo will,but run anything hard enough and it can tear up the drivetrain parts no matter what engine is in front of the given driveline.
Honestly,those 6X-4 heads are a fairly safe bet if the price is right,and if your remotely concerned about the CR deal,that's easy enough to fix if you really want to,see silly me that's why I asked the questions I did (is it already built/or just being planned),instead of just dictating some sorta mandatory manifesto for all to follow on CR for street cars.
The other thing is cams,ahh yes,cams,well the problem there is one can easily think they're getting one thing,when in fact they're getting something completely different,so when I hear terms like "throwing cam at it" I get more than a bit leary of where that talk is gonna take a fella.
It takes a huge change in IC event timing to make the sorta difference that rates the "best" to "worst" choices on a combo like this.
Typically your talking about a range of like 15° to 20° of intake closing difference.
That's a
LOT.
An 041/RAIV style hydraulic is gonna close the intake @ like 81° ABDC.
A cam like the SD ol' faithful is gonna close the intake @ like 72° ABDC.
A cam like the Crower #60243 is gonna close the intake @ like 70° ABDC.
And a cam like the XE274 is gonna close the intake @ like 63° ABDC.
All are pretty close @ .050",but they're worlds apart on the actual
seat/advertised intake closing event timing.
But unless you really understand cams,and you dont watch the actual valve event timing,it's easy to lose sight of all that.
And me personally,I dont like to use the cams to "crutch" any compression ratio choices,that is not unless there is simply no other possibly choices/options to address the compression ratio situation itself.
Not to "bleed off" high compression.
Nor to "pump up" low compression.
Pick them both wisely,and you should'nt ever get into trouble.
If I were gonna look for solid flat tappet cams for something like this,I'd probably look at the Crower #60311 solid (IC 74° ABDC),and as a side note that solid cam is actually
very comparable to the SD racing ol' faithful HR cam if one looks at the actual valve events and such.
Of course the solid FT cam would require 1.65 rockers to match the lift of the HR cam with 1.5 rockers,but other than that they are a dead heat in most all respects.
I'd bet $$$ those two cams dyno'd in the same engine would be within 10-15 hp of one another.
And I could'nt tell you which one would be the winner either.
So there is more than one way to skin that cat as well.
Me,I see this sorta thing as a infinte number of possibilities.
While others seem to choose to see but a few of those.
Which is fine really,different strokes for different folks.
(pardon the pun,,,yeah I know that was rrreeeaaalllyyy bad...)
Bret P.