Added 4/22/94

SplitFire Plugs

No noticeable improvement in power, acceleration, or fuel economy.  A few Saturn owners as well as service technicians (as read about on the newsgroup) have reported problems with SplitFire plugs.  I had no problems for the time that I used them, but have since switched back to normal plugs.   I did notice that each plug's center electrode edge tended to wear and round off quite quickly (possibly due to Saturn's ignition & coil system?).  In my opinion, at $5 per plug there are better ways to spend your money.  I won't be using them again.

I never realized how bad the stock Firestone Firehawk tires were until I tried these.   These tires were rated #1 by Consumer Reports, and even beat out Goodyear Eagle Aquatreds which cost twice as much.  I wanted to stick with a medium tread life all-season tire that was the same size as stock.  I ordered up a set of these from the Tire Rack for under $250, which is quite a bargain.  No noticeable increase in noise or change in ride quality.  But in cornering, on snow, on wet pavement, or on dry, they were quite an improvement.  Their treadwear number was very close to the stock tires, so I expected them to last just as long.  As these tires got down to about 1/3 of their tread, their snow & wet performance dropped off and became very much like the stock Firestones.

Added 7/25/95

3/2000:  After driving on Gingerman Raceway's road course with the Nitto tires that replaced these, I'm even more impressed with the level of performance I'd received with these Dunlops.  For around $55 each, they're one damn good tire for snow, rain, dry, and even the occasional day out on the track.

Added 8/1/95
  

GTS Tail Light Blackouts

Yes, I realize that these really aren't a performance enhancement, but boy do these things really look nice.  They come with industrial-strength Velcro to attatch them to the stock lights.  I ended up using a few dabs of silicone to attatch the smaller inner two pieces because the Velcro made them stick out from the reflector panels way too far (about half an inch).  They didn't nearly stick out that much from the actual tail lamps.  I tend remove the outer covers for everyday driving, and put them on for the occasional cruise around town or during car audio competitions.  If you're considering putting a set of these on, make yourself aware of the laws in your particular state.
  

This was the first real improvement that I added to my car (after the audio system, of course).  I remember finding SPS's site a few years ago and following the link to Hotshot Performance's web site.  They had a sound clip of what my car sounds like with one of their intakes, and that was all it took to sell me.  Now, I'm not the type that likes an obnoxiously loud car or likes to attract too much attention.  The sound of the engine with the intake alone is amazing, especially with the gas pedal on the floor.  It's probably best described as a deep throaty roar under hard acceleration.  And the best part is that it's not even noticeable at idle or cruising speed.   The chrome finish really looks great in the engine compartment and shows that it's definitely not stock.

Dyno charts of the intake alone show a loss of a few horsepower at lower RPMs, and gains of up to 5.8hp above 5000 RPM.  I can't say that any power loss my car experienced was noticeable - maybe that was due to the incredible sound that I now enjoyed.  With the other modifications I've made, I'm sure that the intake adds to the net gain in horsepower.  SPS now sells this intake with K&N filters, but I decided to keep the black foam filter that I received with it and replace the blue silicone hoses with black to better match my engine compartment (as the engine is viewed at the car audio competitions that I attend.) 

Added 8/6/96

Click HERE to hear a Saturn
with a HS Performance Intake (52k)

Pic courtesy SPS (thanks!).

Added 8/2/97

Pic courtesy SPS (thanks!).

Borla Stainless Cat-Back Exhaust System

About a year after installing the Hotshot Intake, I found this exhaust system on the web used and picked it up for a great price.   I probably wouldn't have bought it new, as it does run a bit more than many other performance add-ons.  The fit and construction on this system are great - I can see why it has a million-mile warranty.  I could definitely feel a power increase after installing this system, even at lower RPMs.  There seemed to be more low-end torque, as I could now be rolling at about 10 mph in first gear, tap the gas, and easily chirp the tires.  I don't remember being able to do that previously.

This system also dramatically changes the exhaust sound, and the engine really doesn't sound like a 4-cylinder any longer.  It's quite deep and has a bit of a burble at idle and during engine braking like many larger V8's with low-restriction exhaust systems do.  It does make the exhaust a bit louder at idle, and quite a bit louder during hard acceleration.  There is also a low constant drone at highway speeds.  The day I put it on I felt that it was louder than I wanted - it took me while to get used to but now it's just fine.

SPS dyno charts show power & torque improvements at all RPMs, with a max gain of about 8 horsepower.  Hey, every bit helps and it definitely adds up.

You can hear a recording of my 94 SC2 with this exhaust system (plus Hotshot header, Random cat, & Nitto tires) HERE.

UPDATE:  This exhaust system is no longer made by Borla for Saturn S-Series cars.

The brace seems to make understeer during high-G cornering more predictable - a crack in the pavement or uneven road is less likely to make the front end suddenly slip and momentarily lose traction when at higher RPMs.  There is very tight 180 degree, 25 mph highway offramp near my home and the brace made a noticeable difference at higher speeds.  It also makes the front end feel less skittish on rough or uneven road surfaces.  This addition made the engine compartment look a lot nicer, especially after I took the time to buff and polish the aluminum.  This is a nice piece if you really like spirited drives on twisty roads or if you're going with lowered springs and/or sway bar & bushing upgrades.

Added 7/28/97

Pic courtesy SPS (thanks!).

4/2000:  On 1991 cars, the design of the cam cover & oil fill cap will require you to undo and lift one side of the brace in order to add oil.   I found this out when I swapped my '94 cam cover with one off a '91 (I don't recommend that you do this as it will require machining due design differences in the top motor mount - a fact that I didn't know until the '91 cam cover was already polished and ready to go on).  There are now more manufacturers that offer different strut tower brace designs that won't affect oil cap access in this way on older first gens.

  
Added 4/19/98

Pic courtesy SAP (thanks!).

In SPS's dyno charts, this header appears to be the single part that gives the most horsepower & torque gain.  Installation was a bit time-consuming, as the air conditioning compressor has to be removed and moved out of the way (which can be done with the coolant hoses still attatched).  Be sure to get a new gasket to go between the header and the head.  I made the mistake of using the old one and had to redo the job because of leaks.  Use gasket sealant on the downpipe flange as well.  I was surprised and a bit concerned about how close the downpipe came to the underside of the engine - there was only about 1/8 inch clearance between them.  No problems so far though. SPS dyno charts show power & torque improvements at all RPMs, with a max gain of about 7 horsepower.

UPDATE:  Many people who have installed this header have had problems with the weld joints cracking.  Since the bracket that holds the stock manifold downpipe to the underside of the engine will not fit the new header downpipe, most people will leave it off and won't bother to fabricate a new one.  When the engine twists on its mounts under torque, it will place a lot of stress on the weld joints if the bracket is not in place.   If you're going to go with this header, be sure that a bracket is installed on the downpipe in front of the flex joint!  You can see a picture of a bracket that I made for under $3 in about a half an hour HERE.

7/98:  Well, the header finally cracked at the weld joint on the Y closest to the block (pic HERE) .  It doesn't feel or sound like it is blowing exhaust, so the crack must still only be through the outer weld.

8/15/99:  The original paper gasket between the header primary and secondary pipes disintegrated and blew out - most of the damage was probably done by the insane track time during the 1999 SPC Rally.  I bought some hi-temp gasket material from a local auto parts store and made my own (since the car really sounded like crap and I didn't want to wait for one to come in the mail).

8/26/99:  The second gasket gave way while out on the track at my second Gingerman session.  When I returned, I ordered a replacement from SPS.  This one was a beautiful copper piece that's sure to outlast the previous two (pic HERE).   The bolt holes did need a few millemeters of material removed in order for it to fit properly.

7/2/2000:  After checking with SPS multiple times during the last year, they finally had a replacement header primary (top half) in stock.  The new piece was supposed to be redesigned and improved so it would be less likely to crack like my old one had.  The crack and exhaust leak from the old primary had recently become worse and was now easy to hear.  Upon removal, the crack was more visible when viewing the header from the rear (see pic HERE).
   The new primary felt a bit heavier and looked nicer.  The ceramic coating had more of an appearance of chrome than the old piece.  Unfortunately, there were problems visible also.  The bolt holes to join the top half of the header to the bottom half needed to be drilled out a bit to remove slag and allow the bolts to fit without using a hammer to put them through.  The gasket mating surfaces looked uneven, and there were drips present from the coating that was applied.  And worst of all, the tube on exhaust port #1 (closest to the left side of the engine) had a more gradual downward bend than the old primary.  The air conditioning compressor bracket no longer fit over the new header primary!
   After several hours of work with a dremel and a saber saw (using cutting discs & very good blades), I was able to cut a hole in the bracket's 1/8" thick metal that would allow the bracket to fit over the header (see pic HERE).  What a pain in the ass.  I would suggest not buying one of these 'new and improved' Hotshot headers if you have air conditioning because it won't fit without a lot of grief - unless Hotshot is able to provide a replacement air conditioning compressor bracket that will clear the header primary.

10/1/2005:  Winters with a lot of snow and road salt have taken their toll on the wire braid that covers the flexpipe section - see a picture HERE.  There do not appear to be any leaks caused by this, so it appears to be cosmetic only.  Even though the header has been on the car for over 7 years, I would not have expected the wire braid to have rusted out like this.  After all, I have a OEM Saturn header on my 92 SC, which is now 13 years old and its wire braid over the flexpipe is barely showing any rust at all.  This is further proof that the OEM header's materials and construction are significantly better than any aftermarket header on the market.

11/2006:  After doing some recent work where I was crawling around under the car, I can see that the header downpipe is on the verge of rusting completely through in two different places.  In addition, I can see the start of a new crack in the primary which was supposed to no longer be a problem with the "redesigned" replacement primary that I'd purchased in 7/2000.  I picked up a '92 OEM header which will replace this Hotshot header sometime in the near future.  The OEM piece has proven to flow similarly to any aftermarket, and has significantly better fit and build quality.  They will generally outlast any aftermarket pieces as well.  I have one of these on my '92, and you can read about it HERE.

7/2008:  The most-recently replaced Hotshot header primary (redesigned to prevent cracking) has cracked. In addition, the exhaust sound has been growing steadily louder over the past 6 months or so.  When I crawled underneath the car to take a look, I could see that time and weather had taken their toll.  Not only had the braided wire covering the flex section completely rusted away, the flex section itself had several holes rusted in it.
    

Click any of the thumbnails above for a larger version.
  

Random's cats looked like the best engineered that I found in the research that I did (and they probably were the most expensive as well).  I figured that since I was going the extra distance to get an aftermarket converter, I wanted one that was really going to make a difference.  The information package that Random sent me was top-notch, including results on flow tests for stock converters versus their high-flow converters which actually clean the exhaust better than stock.  They offered direct replacements for many cars, but Saturn was not one of them (although now they do offer a direct-fit for Saturn).  I took measurements under the car of the space available, the stock unit, the header outlet size, the Borla's inlet bolt pattern, and they welded up a custom cat to bolt right up and had it to me within 2 weeks.  The price wasn't bad for the work that they did, and these suckers are really built solid.  I had a hard time tightening the inlet U-bolt tight enough to prevent leaks because the inlet tubing was so thick.  I later replaced the U-bolt type clamp with a band clamp which made a much better seal.

The effect of these two items (header & cat) on performance still surprises me to this day.  I now noticed quite a bit more low-end and mid-RPM torque.  I can be doing about 20 mph at 3500 RPM in first gear, tap the gas (without touching the clutch), and break the tires loose. The sound of the Borla exhaust at that RPM along with the short high-pitched squeal of the tires until they finally grip is quite an impressive sound, and feels pretty good as well since the car is already moving at a typical city traffic speed.  The lower RPM gain surprised me - from what I'd heard, increasing the exhaust diameter and lowering backpressure was supposed to yield upper-end gains at the expense of a bit of the lower end.  I was expecting to lose a bit off the line, but that was definitely not the case.

Added 4/19/98

7/98:  The constant high-RPM vibration during the autocross held at the Saturn Plant during our Spring Hill Trip '98 seems to have knocked loose one of the 'brick' elements inside the cat - this could be heard as rattling & vibration at certain RPMs as well as a clunk when I shut off the car.  Random put together a new one and cross-shipped it for me - all happily covered under warranty.