View Single Post
  #59 (permalink)  
Old 12-01-2010, 08:03 PM
ERA Chas ERA Chas is offline
CC Member
Visit my Photo Gallery

 
Join Date: Oct 2003
Posts: 4,078
Neutral     
Default

Quote:
Originally Posted by zrayr View Post
...for a street driven FE 427, at what point do power modifications begin to seriously degrade longevity & reliability? 500 HP, 550 HP, 600+ HP ?
Z.
Z,
I really like your car. And I offer my own experience to help you decide the answer to your question. But after that I have to address the rampant nonsense which has jacked your thread. Forgive me-"I can't stands n'more" as Popeye used to say.

I've pushed 550 HP at 427 inches around the streets and track-for a long time. Since '03 when I installed Shelby heads, it's run 11's at the track, had 4 valve adjustments (.600"+ SFT cam) and no broken parts. Goes to 6800 when I feel like it and I've had to change a clutch disc in '09. Since the previous disc in '95. Considering the performance, I'd say that it's reliable. You decide.

Brent, why are you fencing with our nerd in the shop class?
Time for some 'Mythbusting' and I'm here to help.

Patrick, or would you prefer Mr. T? You're a very intelligent and resourceful guy. But your real talent is manipulation. You know:
A. If you repeat fallacies often enough to a less discerning audience, they will become 'fact'.
B. Spouting posts and threads from the net without your own experience and brow-beating others to support your stance is BS.
C. Rod's 600 is STILL a lot more than your 450-pipes, pumps or an 800 pound gorilla in his car not withstanding.
To wit:
I watched 3 DTS dynos run 3 engines a day. Dynos were calibrated annually by DTS. Those engines had no (mechanical) fuel pumps, water pumps or alts. On rare customer requests we ran a water pump or alt. The back to back loss of a water pump was 5 to 8HP at power peak. An alt. was 2 to 4. Dunno for sure but I don't think a fuel pump is more than 3 or so HP. All the dyno headers were very efficient and went into 2 large corrugated tubes which went out of the building and into a pair of Flowmasters. Like you, here's a little support from Stewart if I have no credibility:
http://www.stewartcomponents.com/tech_tips

See that at 150GPM, the HP consumed is 8.8 for a SBC.

My own Cobra experience is more telling. Firstly, you can thank me for your Stainless Specialties pipes. In 1989, I called Lou and asked for a set of Cobra stainless sidepipes.
He said; 'What's a Cobra?' and ' Show me what it looks like and I'll make 'em for you'. So I sent one mild steel ERA pipe to NC and Lou suggested I came down for a talk. I did, we did and the deal was I buy the doming die and I get the prototype set of pipes to have and to--test. Having them fit perfectly and look beautiful, I put Lou in touch with Peter and the rest is history as they say.

But I was aware that sidepipes eat HP and in a year or so I told Lou I wanted to find more. He too realized that the original 2" core was hurting so he whipped up a new set with a 2.75" core. But I told him to cut and flange the collector for a small turnout for the track-true open headers. He said fine provided I chassis dynoed a comparison. And now on to that:

When first machined and built my 427 made a best of 530 with non-ported iron med. risers, my then OE water pump and Hooker 1.75" dyno headers (too small by .250") Also had stock iron (1.73) rockers.
In '03, I bought and installed Shelby Stage II's and Sharp roller rockers and stands. I've maintained that they added 20HP to the combination. And then I went to Matt Grillo's chassis dyno which Mike Ashley's Pro Mod had pegged at 2000HP the week before.
First tests were the early sidepipes, then the new version and then the open headers.
First set: 402WHP
New set: 457WHP
Open headers: 462WHP
The amazing thing is not the 55HP gain over the first design, but rather that the second design was only 5HP away from open headers. And of course all the primaries are 2" pipe unlike the build dyno tests.

So, as I questioned Sharapa in his dyno thread, the parasitic losses are no where near 26% as you're preaching to Rod and less than the 22% he and his friends have seen.
My numbers work out to 17.5 to 18.5% consistently. And the local IRS Cobras I've seen are comparable. A live axle car may be less-the big transmission gears in Richmonds and TKOs can add to loss -so we can only generalize.

So please stop perpetrating myths-it doesn't help make other guys smarter or understand things better. And quit harassing Lykins-he's done a thousand builds and tests. He's trying to make a buck and share his time and experience. And don't get all kissey-face with him either.
__________________
Chas.
Reply With Quote