SPF Headers and side pipes

[Dana E.]

The later model Superformance stepped headers and stock side pipes aren't as bad as some would have you believe. Just thought I'd throw that out there.

[Silverback51]

A picture on an engine dyno prove what?

And I'm not trying to be an ass, but I'm confused what you are trying to say.

[Pman1961]

Dana....what comparisons did you do? Sidepipes on and off? I went with Performance Engineering modified pipes 3" baffle no packing on my SPF with 445sbf. The sound alone is worth any performance I may have gained. Of course you gotta like loud! My buddy picked up 38hp (don't know if flywheel or rear wheel horsepower) per Olthoff using the Firefly pipes over the stock pipes. Our motors are very similar constructed with the exception he has 427sbf. I'm happy with my pipes but those Firefly's are beautiful pipes!

[Hydramada]

Ron Roberts ( Specializing in Superformance after market ) makes some beautiful side pipes in addition to being one heck of a nice guy. I could not be happier with the sound, the quality of the construction or the aesthetics of these stainless steel pipes. Performance improvements were an added bonus but not the main goal. I elected to go with ceramic coating rather than polished pipes.

[Dana E.]

Perry,

I compared the Superformance pipes (mine have a 2.25" flow path), Gas-N polished stainless steel pipes (beautiful pipes but have only a 2" flow path.....more on that later) against the dyno headers with no mufflers, which were a 1 5/8" X 1 3/4" stepped header. I ran the tests with the motor set up as it would be run in the vehicle: water pump, alternator, K&N 2 1/2" tall oval air filter, PCV valve, crappy Oregon pump gas and compared the readings with a run with dyno headers and no air cleaner in place. The SPF and Gas-N pipes were side by side to about 4700 RPM when SPF pipes pulled ahead slightly. The Gas-N pipes did catch back up on top. The average HP loss with the SPF pipes, not counting the loss with the air filter installed, was about 25 HP....and it was closer than that at the horsepower peak. Both sets of side pipes are fairly quiet.

[Pman1961]

Dana, I was under the impression the stock sidepipes per previous posts have a 1.875" baffle. I can understand why the results are as you stated. Been curious what the results would have been with a comparable pipe to mine. I know you've got a new sweet motor. What were the results of the dyno?

[madmaxx]

Wow, more details, can u post dyno charts. Chassis or engine dyno. Gas n go ate gouergeous

[Pman1961]

Dana....back to the Gas-N pipes. I called them when they began offering pipes for the SPF. Since I was increasing my power output with my new combination by 200+ hp I was looking for pipes that were not to restrictive. I recall at the time and maybe still today they did not offer a combination with a 3" baffle or even 2 1/2". Gas-N makes a nice looking pipe and offered at a great price but I wanted larger baffles is why I went with Eric at Perf Engr. Like Mr. Hydramada...I prefer the ceramic coating look and did not wish to deal with the upkeep of stainless. I'm sure I'll start something with that quote but just my humble opinion. Didn't you build and is this on the dyno the 427dart block with KCR heads after the 393w?

[Dana E.]

Originally Posted by Pman1961

Dana....back to the Gas-N pipes. I called them when they began offering pipes for the SPF. Since I was increasing my power output with my new combination by 200+ hp I was looking for pipes that were not to restrictive. I recall at the time and maybe still today they did not offer a combination with a 3" baffle or even 2 1/2". Gas-N makes a nice looking pipe and offered at a great price but I wanted larger baffles is why I went with Eric at Perf Engr. Like Mr. Hydramada...I prefer the ceramic coating look and did not wish to deal with the upkeep of stainless. I'm sure I'll start something with that quote but just my humble opinion. Didn't you build and is this on the dyno the 427dart block with KCR heads after the 393w?

Perry,

I orderd, and was told I was getting 2 1/2" Gas-N pipes. What I received was 2" pipes. I talked to the guy that builds the pipes and he says these 2" pipes will easily handle over 600 horsepower and you don't need to go 2 1/2" or larger. They seem to be no worse than the stock pipes at the low 500 horse level. We'll see if Gasn-N comes up with the 2 1/2" pipes for me. Yes, that's my 427 on the dyno. With the too small 750DP, Air Gap manifold, 2 1/2" K&N oval air filter, alternator, water pump, etc., it made 494 HP through the mufflers.

[DanMartin]

Dana, we really must meet up some time (I'm local!)

Very interesting stuff...

BTW: There's a place south of Hillsboro on 219 that sells straight gas (E-0).

[ACademic]

Does anyone know where Gas-N or Ron Roberts sources their mufflers? Are they using Classic Chambered or some other brand? And does anyone have YouTube links to either the Gas-N or Rob Roberts pipes on a car? Hearing is believing.

[madmaxx]

go to you tube and search gas-n, some guy with a factory five did exactly what you are asking.

[Rare Iron]

Originally Posted by ACademic

Does anyone know where Gas-N or Ron Roberts sources their mufflers? Are they using Classic Chambered or some other brand? And does anyone have YouTube links to either the Gas-N or Rob Roberts pipes on a car? Hearing is believing.

Neither are buying from me.

Dana - 2" muffler cores will "easily handle" 600 HP? That is not true at all - not even close. You will see a very significant HP & torque loss through that size core with 600 HP. I wouldn't recommend using a 2" core muffler on ANY V-8 - not even a 289 2-bbl '66 Mustang.

[Dana E.]

Dana - 2" muffler cores will "easily handle" 600 HP? That is not true at all - not even close. You will see a very significant HP & torque loss through that size core with 600 HP

I'm just relaying what the builder told me: the collector, the exhaust gas temperature and velocity all play a part in how well the exhaust system works. I can't comment about the 600 HP level, but at the 500 HP level, those 2" cores were down less than 20 HP at the horsepower peak (5900 RPM) compared to the dyno headers with no mufflers. Looks like the guy just might know what he's talking about. Someone with an honest 600 HP motor will have to bolt on a set of these pipes and see what results they come up with.

I wouldn't recommend using a 2" core muffler on ANY V-8 - not even a 289 2-bbl '66 Mustang.

In the case of the GAS-N pipes, those 2" flowpath mufflers work pretty good and are somewhat quiet. They do look good and have a bit of a "crackle" to the exhaust sound.

I'm supposed to be getting a set of 2 1/2" core Gas-N pipes. I may do a before and after muffler test on a chassis dyno with the new pipes.

[mattpatt]

It's been a while and I came across this thread. Just some more info for folks. I have SPF #3033. It came with 2" mufflers (as near as I can tell by measuring the ID of the mufflers). The engine is a KC 427W (just a basic induction - 780 Quick Fuel, Air Gap manifold). Attached (I hope I did the attachment right) are the fly wheel HP/Torque curves at KC compared to the rear wheel measurements (inertial dyno in 4th gear). The torque lose across the band is about constant and doesn't show much evidence of "choking" from the exhaust (i.e., more loss as the rpm increases). The total loss across the band is about 26%. Assuming around 20 hp peak hp loss the rest of the losses account for about 20%. I would have expected more like 15% so maybe the pipes have a bit more loss (or maybe the dynos account for difference)? Anyway, it's plenty of power for me with a reasonably flat torque curve and I'm sure my neighbors wouldn't appreciate the car being louder than it already is (I set off 6 car alarms coming home from breakfast last week).

Matt