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Flow to Go!
Mar 16, 2005
MagnaFlow Performance Exhaust
Rancho Santa Margarita, CA 92688
Johns Customz & Performance
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Flow to Go!
Here is our starting point bone stock small-block. From the air cleaner all the way to the exhaust manifolds and beyond it is pretty much as-delivered 40 years ago.
After removing the factory manifolds, John at Johns Customz chases the threads in the head as a precautionary measure.
With a relatively empty area the right bank headers slide in with minimal effort. Sufficient clearance is allowed so that you can run regular size spark plugs.
The left bank installation proved to be a bit more challenging as we needed to loosen the motor mount to lift the engine slightly. With that, things went pretty much as expected.
With the header in place we used a combination of the provided bracket and the factory alternator bracket to hang it and secure the rear of the power steering pump in place.
With everything topside in place and torqued to specifications, we went downstairs and hooked up our exhaust pipes to the collectors. John and Paul matched up the stock pipes to the new header collector outlets. This muffler clamp "forest" is a temporarily fix to let us drive the car over to the dyno.
Back on the dyno we saw an extra 10hp and 14 ft. lbs. of torque with the header-only installation running through the original pipe and mufflers.
Here is our starting point or should we say our curvy mess of a system as we got started at MagnaFlow's Tech Center. The Hooker Headers added horsepower but were jammed into an antiquated set of pipes and mufflers.
The first step was to clear the underside of the car of the old ratty system. Jose got out "our" favorite tool, a sawzall, and made quick work of ridding the car of past sins.
To get a better look at the complete system we put all the parts together on the floor. Note the smooth contours and even bends to aid gasses out the back quickly.
A close-up of the Tru-X crossover shows just how smooth this feature is over conventional H-type crossover systems. The extra vacuum that is created helps pull exhaust gases through the system for increased flow while controlling sound levels.
The Tru-X and intermediate pipes fit the bottom of the car like a glove.
The only modifications needed to the car for the system is to drill out the hanger holes from 5/16" to 3/8" to accommodate the new bolt-style muffler hangers.
Now we're getting to the good stuff as Jose slides the first of the mufflers into position. Like our trial fit outside the car, it is a good idea to get each component in place before tightening anything up.
Jose is about to do the only cutting and adjusting needed with the MagnaFlow Crossmember back system. Two pipes with 45-degree angles are provided to allow hook up to any header system. Designed with one length longer than the other--check fit each way, measure twice, and cut once.
With the front of the system intact we moved to the over-axle pipes. Installation Tip: Notice the level on the muffler to insure that the system is level from both front to back and side to side.
The MagnaFlow Crossmember Back system comes with three different exit locations. We choose the over-the-axle and out-the-back as opposed to out-the-side that we had been running. Guess we just felt it looks "cooler."
The last step before everything gets tightened up is to add the polished stainless steel tips. Again with attention to details, Jose aligns the tip to the bottom of the bumper and then checks to insure that everything is level.
The final finish is the trick branded MagnaFlow stainless steel tip that lets you tell everyone what's down below. Of course, once you crank it up they know anyway.
The transition from the headers through the collectors and through the Tru-X cross-over pipe is smooth and clean. The pipes where welded to the collectors and all other joints were secured with the ultra-trick clamps that are provided with the system.
Looking from the third member forward the drastic improvement is obvious. Plus, there is plenty of clearance around all the underside components. The end result looks so good it is a pity we can't park the car on its roof to better show off this new system!
Here are the dyno results from our Flow To Go project from the PRIMEDIA Tech Center DynoJet. We went from 147.2hp to 165.2hp for an 18 hp gain. Actually we think we just plain ran out of engine, as this system was ready for more--so where did I put that 383 stroker?
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