Longevity & Reliability vs. Power

[RodKnock]

Uh, so, what's your point? There's nothing new here. No new ground covered.

I see something that says sidepipes are the biggest power robbers and I had mine cut off and replaced with allegedly higher flowing/less restrictive pipes.

[patrickt]

Originally Posted by RodKnock

... I had mine cut off and replaced with allegedly higher flowing/less restrictive pipes.

But you didn't have the numbers checked. That's unlike you to just take a set of numbers "on faith." Uhhh, what do you think those horsepower numbers for a 610 engine less 25% turn out to be?

[madmaxx]

FWIW an engine which does not run or is not reliable or as important cannot be trusted is no fun. I like Kirkham reply, keep it under 5.5K rpm's, if you need more power then go more cubic inches. Valve train is the weakspot. The lighter the spring pressures, ie milder the cam, the better the reliability. Speed kills not only people but also engines. I would much rather have 600 ft-lb of torque and 400 hp than 600 hp and 400 ft-lbs of torque. 99.99% I am driving WELL under 100 mph, torque is fun.

[blykins]

zrayr,

Feel free to give me a call. Advice is free. 502.759.1431 There are a ton of parameters and variables associated with horsepower, reliability, and longevity. Again, 5500 isn't a magic number....neither is 5000 or 6000. There's not really a set standard to what will live forever and what won't, but most engine builders have an excellent handle on what works and what poops the bed.

[patrickt]

Originally Posted by blykins

Feel free to give me a call. Advice is free.

... and it's worth every penny of it. Seriously, zrayr, Brent is top notch. If I had known hiim 5+ years ago I would have had him build my FE.

[ERA Chas]

Originally Posted by zrayr

...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.

[patrickt]

Uhhh, ok then... "thank you" for my pipes, and if I want kiss Lykins, that's my own business.

[RodKnock]

Originally Posted by patrickt

Uhhh, ok then... "thank you" for my pipes, and if I want kiss Lykins, that's my own business.

Always call for back up.

[rodneym]

To the experts (EXPERTS!!!):

Doesn't it stand to reason that if you have a set of pipes (no matter the brand, let's just keep them constant in this example), and you have 20-25% HP loss on average (expert opined), wouldn't you get a higher percentage of HP LOSS on a 800 HP engine vs a 400 HP engine? Remember, the headers and pipes are the same for both engines in this case. It would seem to me that the same headers/pipes would do more choking on a higher powered car.

Or is the difference negligible?

[blykins]

Yes, you're correct....

If you start at 500 fwhp and lose 20%, you've lost 100 and you're down to 400.

If you start with 700 and lose 20%, you've lost 140 and you're down to 560.

And I believe that if a certain size exhaust system is restrictive to a 500hp 400ci engine, it's going to be even more restrictive to a 700hp 500ci engine.

[patrickt]

Originally Posted by rodneym

To the experts (EXPERTS!!!):

Doesn't it stand to reason that if you have a set of pipes (no matter the brand, let's just keep them constant in this example), and you have 20-25% HP loss on average (expert opined), wouldn't you get a higher percentage of HP LOSS on a 800 HP engine vs a 400 HP engine?

I think you're absolutely right, and I think Keth is being painfully honest in his post. I know Barry R. is busy with his cammer (from the FordFe thread), but it would be interesting to get his input on it, as well as Jerry C.'s input.

[zrayr]

Originally Posted by ERA Chas

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.
....................."

thanks for reminding me. Yes, your answer is to the point, and well taken. I was hoping to hear this side of the discussion. thanks for taking the time ......

Z.

[RodKnock]

I'm not ready to believe that there's a linear relationship like that without some dyno testing using all the same equipment, but for the engine.

[patrickt]

Originally Posted by RodKnock

I'm not ready to believe that there's a linear relationship like that without some dyno testing using all the same equipment, but for the engine.

Absolutely correct. The loss will not be linear, it will be exponential. The larger the engine, the larger percentage of loss.

[rodneym]

Originally Posted by patrickt

Absolutely correct. The loss will not be linear, it will be exponential. The larger the engine, the larger percentage of loss.

That's what I was getting at. All pipes being the same, you might get 20% loss on a 500 HP build and 25% HP loss on a 700 HP build. So you would lose 100 HP on the first engine and 175 HP on the second (just an example).

[blykins]

Yep.

Take a 302....you can run a 1-5/8" header tube on that one....try running 1-5/8" headers on a 557

[patrickt]

Yep, Rod... I'm going to have to start drawing you graphs. I am just loving this thread.

[RodKnock]

Couldn't you design, let's say, and 850 HP SOHC engine, employing concepts of quench, piston/chamber design, cam and EFI technology, etc., etc., that would lose less HP through the sidepipes, as a %, than other 850HP FE engines? Are all 850 HP FE engines created equal.

[CobraEd]

When I upgraded from my original PoS Classic Roadsters sidepipes to a custom set of stainles pipes, I picked up a ton of power. I did not dyno it but seat of the pants was day and night. Anyway, . . . I now have 4" oustide diameter stainless glasspack sidepipe mufflers with 3" inside diameter. We keep talking about hp losses of sidepipes, but it is hard for me to imagine that I am losing a lot with a straight thru 3" ID glasspack. The case is about 30" long, it is not a shortie. It sounds very good to me


.

[zrayr]

so the consensus is, consistently hitting a 6000 rpm redline in a 427 FE will put cross country reliability at risk.

Z.