[TA454]

Originally Posted by Velox65

Get a pair of these for a 421 and run em against a BBC and we'll see who win's

it was tried. yes they did work good but not good enough!!
still had the same problems of size limitations,duribility of the internal components.

[7T2]

WOW- how interesting...
i spent the day flow benching a couple of different BBC heads. an edelbrock performer rpm and a open chamber rect iron head.
impressions:
the first thing are the visual differences between the "good" intake port and the "not so good" one. 40cfm worth of difference @ .700". the 26 degree primary intake valve angle requires such a deep chamber-no wonder theyre all 110+cc. the valves are huge. conventional wisdom says for better breathing. but the valves and chambers overlap the cylinder walls even on a 4.5" bore fixture.
ive never flowed bbc stuff before, but they sure do look intimidating at first glance. the rect port has a huge opening, but the port design doesnt follow the valve cant? it only flowed marginally better than the much smaller perf rpm 335 vs 320(again good port). 4.25 bore.

ive gotta hand it to you TA454, you take all the guff and come right back in when the bell rings. that in itself deserves respect.
but i gotta ask the burning qwuestion:
if a canted valve pontiac head-big valve covers and all-became available. with out-of-box matched flow #'s of brodix, merlin,etc- at the same or better price-using off the shelf valvetrain componentry; would you put a poncho back in your TA?
jim

[TA454]

Originally Posted by 7T2

but i gotta ask the burning qwuestion:
if a canted valve pontiac head-big valve covers and all-became available. with out-of-box matched flow #'s of brodix, merlin,etc- at the same or better price-using off the shelf valvetrain componentry; would you put a poncho back in your TA?
jim

If i had to start from scratch. With no usable parts -Buying everything from the ground up. As long as dollar for dollar. The durability issues were addressed(No risk of lifter bore breakege, forged crankshaft availibility,ect..}
sure i would. But the forged cranks will NEVER be cost effective compared to the chevy. The stock pontiac block will allways have a tendancy to break the lifter bore.

Besides with the GM crate engines it is a no brainer any more. It is not worth building an engine yourself anymore.Hopefully my next move will be a GM 572. In a few years.

[7T2]

just pulled these #'s from my handy summit catalog. a gm perf parts zz572 lists for 13g's + s&h. its complete from carb to pan. 620 hp on 9.6cr. hyd roller. world products has a 675hp entry w/alum heads for $11,5
comparing those hp #'s to www.butlerperformance.com, they have a carb to pan 650hp entry for 11g's +s&h. but its a stock block and cast crank. fewer cubes and probably not as durable as a new gmpp block. but if you upgrade the stock poncho for a new ia or kre- the difference in price would probably be about $12-1400 more, since you dont have to pay for all the block prep and 4 bolt caps, line bore, etc. if youve seen the race boards lately, you know that IA is set to release a group of forged cranks this summer. 4-4.5" stroke for $11-1400 target.
add these two upgrades in and you have a 540ci poncho that should have the same durability as the chevy- for about the same price!
lets face it, 13gs is alot of money- if youve got it...
can you hook a brother up?????????????
jim

[TA454]

1400 is what the complete rotating assembly cost for my current 496.

"lets face it, 13gs is alot of money"

Notice i said "hopefully" in refering to the 572 . In reality it is what it is and most likely it is staying. If anything might lower compression to make it more streetable/less dependant on race fuel.

[7T2]

okay,
summit forged bbc 4.25(496) strokers are $750. rebuilt 7/16" bolt hi po rods are probably cheap $200 or so, and 1.415" pin ht stroker pistons are around $4-500. summation agreed.
plan b- forged ia stroker $1250(median) 6.7" h-beam rods-$500, 450g flat top ross-$500. difference of about a grand....but!
what design rods are included with the $1400 bbc pkg? are they 6.7"?
are the pistons lightweight 450g?
certainly-as you stated, the dominating factor is the "start from scratch" supposition. if you had to buy a poncho block and prep, then these prices are irrelevant.
so do you have any poncho engine parts from your t/a?
jim

[TA454]

My rotating assembly consist of an Eagle stroker crank ,Eagle H-beam rods i think they are 6.8 long, JE SRP pistons. I did upgrade the kit from standard rings to C&A ZGTF for an extra $100.
As far as the original parts I traded a non running 455 and 4 speed for my first (90,000 mile)454 and turbo 400 straight out of a suburban.

[7T2]

was that the street/strip rotating assembly or the competition assembly?

[TA454]

the competition assembly

[7T2]

alright then, lets go to the eagle specialty products catalog (ive got a '05-'06 issue since im a dealer for eagle). hmm, the competition rotating assemblies p/n 11012 is the small solid 18cc dome for 10.5 to 1 cr; p/n 11013 is the hollow 43cc dome for about 12.5 to 1.
WOW! you got an incredible deal for $1400!
says here either of those assemblies lists for $2,218.75. jobber is $1775.00.
did you get that several years back? or was it some kind of "blow out" sale? anyway, if you can still get that kind of deal- this eagle dealer is ready to ditch the factory direct and start buying from TA454.com.

[TA454]

Originally Posted by 7T2

alright then, lets go to the eagle specialty products catalog (ive got a '05-'06 issue since im a dealer for eagle). hmm, the competition rotating assemblies p/n 11012 is the small solid 18cc dome for 10.5 to 1 cr; p/n 11013 is the hollow 43cc dome for about 12.5 to 1.
WOW! you got an incredible deal for $1400!
says here either of those assemblies lists for $2,218.75. jobber is $1775.00.
did you get that several years back? or was it some kind of "blow out" sale? anyway, if you can still get that kind of deal- this eagle dealer is ready to ditch the factory direct and start buying from TA454.com.

Whatever dude my motor was built back in 2001 what is your point.i dont have to justify my choice to you or anybody. So if you have a point to make just come out with it.

[disc0monkey]

people are making over 1000hp on a oem crank by blowing 22psi with twin turbos

[JSAauto]

Originally Posted by disc0monkey

people are making over 1000hp on a oem crank by blowing 22psi with twin turbos

A cast crank huh?? I don't think so. And if someone did or does, it won't last long. Any pro engine builder will tell you that. Ask Rodney Butler... he'll explain it to you.