This portion of The Shop Truck restoration was made possible by Summit Racing Equipment. For over 40 years, Summit Racing Equipment has set and reset the standard for fast shipping, customer service, and tech expertise. Visit Summitracing.com to get your project started!
This needed to be done. Look for yourself:
That’s what came off the truck. And don’t forget these power-sucking rust buckets:
This was supposed to be an easy job. Cut off the old crap, remove the exhaust manifolds, attach some sweet new headers, and pipe the rest. We didn’t even need new catalytic converters, because the truck is considered an antique. We were definitely losing power with this old exhaust system, which leaked and featured a prominent crack in the small cat, seen above. Our last mechanic welded a plate over it as a backstop, but it was time to rip it all out and start fresh.
But this was not easy. It was not quick. It was not cheap.
On the flip side, it came out great. Here’s a little peak:
Except for the unmistakable sound of an engine lifter ticking in the background, I absolutely love the new exhaust note coming from the passenger side of this truck, and it’s a huge step in the right direction.
It’s a huge step in the right direction, but this article is a perfect way for us to underscore the true meaning of BlastCars.com — we are learning this stuff along with you. We don’t know everything, and it really showed this time.
The exhaust system
Summit Racing got on board to help with this job. To do so, the company sent us this kit and stood by to offer us their knowledge when we needed it — and we did.
The kit is pretty basic. In Massachusetts, emissions testing is not required on vehicles made before 1998. So, we’re able to use long-tube headers, mufflers (because we want the truck to sound good, not obnoxious) and piping all around. We could legally remove the old catalytic converters.
The kit is a great way to get started in exhaust, and headers reduce weight and add performance to vehicles. I was most excited to be adding headers to the truck. Every forum you read — even back when I had an Toyota Corolla — people drool over what long-tube headers can do for performance.
I also am a fan of the Thrush Turbo Mufflers. Especially after seeing them installed and hearing the exhaust notes. These are good mufflers for our truck.
A lot of hot A.I.R.
Raise your hand if you’ve ever heard of Air Injection Reaction.
Your dad, maybe. A 30-year-old mechanic? Possibly. Me? Nope.
Huh? What? But just put on the headers and we’ll be good, right? — That was me. Wrong again.
Air Injection Reaction, or Air Injection Reactor, known as A.I.R., became a standard anti-SMOG feature on a lot of cars in the mid 1970s.
You also have your Exhaust Gas Recirculation and Thermostatic Air Cleaner. A combination of these devices and others served to reduce auto emissions, but they robbed engines of a ton of power while adding a level level of complication to automotive mechanics.
Long-story-long, our truck has an A.I.R. system. The system includes small holes in the cylinder heads, which match up the ones on the exhaust manifolds. You can’t just bolt aftermarket headers over top. You have to remove the manifolds and tap and plug each of the eight holes in the eight engine cylinders.
I took to the forums for help, after the cheapest of three exhaust shops in Boston quoted me $1,000 to do the entire exhaust job — half the money spent just tapping and plugging the holes and installing the headers, and half the money spent on new hangers, any additional pipes, tail pipe fabrication, welding, removing the old cats and pipes, and installing the new system with new mufflers. That’s $1,000, and I was bringing in my own headers, mufflers, and most of the pipes already!
None of the mechanics I talked to seemed overly enthusiastic about taking on the job of plugging the holes in the cylinder heads, either. This is despite the fact that most of the articles online seem to indicate that this is a pretty standard get-around for 20th Century emissions hardware.
An exhaustive choice
Russ Capobianco, of Accurate Automotive and Performance in Hyde Park was my first choice for the exhaust job. The shop is known for their craftsmanship and excellent custom work, and Russ’s prices are reasonable. But even he seemed hesitant to start tapping holes into the cylinder heads of an engine that, admittedly, is going to need a lot of work as this project progresses.
I don’t know what we’re going to do, engine-wise, yet.
The team at Summit Racing suggested two routes:
1. Leave the 318 alone other than replacing some parts. If the engine is basically sound, it’s not worth the effort or the expense to tear it down to bore a 340 or 360 out of it.
2. If you want more cubic inches, you’ll be miles ahead by swapping in a late model Magnum 318 or better yet, a Magnum 360. You get better heads, better valve-train, and the option for factory fuel injection. It will probably be less expensive as well, especially if you stay with a carburetor.
Now, those are hugely different paths. Nobody is stepping up to donate an engine to us yet, and I don’t have the money to spend on either project right now (somebody please sponsor us!). So any money I spent — like $500 — tapping holes in the engine would likely be wasted, no matter what I decided to do with the engine later on.
Both Alan and Russ seemed to have a good picture for what I’m trying to do with this truck eventually. Russ, who already had spent a few hours with the truck on the lift, suggested I leave the exhaust manifolds and engine cylinders alone for now. He would take my other parts and fabricate a “true dual” exhaust system, with chrome tailpipes. The system would be “upgradable.” So it would be a great replacement for now, and it would be ready for headers when I decide to get the engine done.
We’ll save the headers for when we know what purpose they’ll serve.
So that’s what you see here.
Of course, staring at the underside of the truck also reminds me that I have to start worrying about the suspension system and the surface rust on the frame. Lots to write about!
What do you think?
Required by FCC: Autosales, Inc., dba Summit Racing Equipment, provided parts for this article free of charge. No other vendors and service providers mentioned in this article provided parts or labor for free or at any reduced price. All opinions expressed in this article are those of the author of the article, and were not influenced by any third party, regardless of parts or services provided.