I've gathered much of this information from other people over the years. Most of this is opinions I've formulated myself from experimentation and talking to people over the net (Dean Marcum, Adam Hintgen, Alan Jordan), so dont take this as the set in stone rule of upgrading. If you'd like to add something, or correct me, feel free to email me at bishop@ma70.com

• Exhaust. There are quite a few options here, and they depend on your budget and how much work you're willing to put in.
  • Cat-back systems/muffler:
    • For those of you who don't mind spending some money for quality, you can get a pre-built system such as Greddy, HKS, Apex-I, Blitz, Random Technologies or Pacesetter offers. 3" exhausts are fine if the muffler has a little bit of restriction. Cat-backs like the Blitz NuR Spec R will flow too much and might result in a loss of low end power.
    • You can also custom build your own exhaust system. Buy your choice of muffler. Here you need to make a choice. Personally I bought the cheapest high-flow muffler I could find ($25 for a 2.5" inlet, 2.5" outlet). If you want something that sounds better, you might try a Dynomax Super Turbo or an A'PEXi N1 muffler.
      • You can get a 2.5" receiving muffler which will hook up easily to your catalytic convertor (cat). Or if you're getting rid of the cat, you can use the pre-cat flange. Or you can get a 2.75"-3" receiving muffler and figure out how you want to convert the stock 2.5" to whichever size you choose. The larger size will be better for top end torque, but you will probably lose some low end. If you plan on doing any internal engine work or getting 275+hp, you should probably go for the 3".
      • After you've chosen your muffler, get a muffler shop to run you some corresponding size pipe from the cat or test pipe to the muffler.
    • Third option would be to get a cat-back exhaust system from a Turbo MK3. This wont give you the most hp, but you may get lucky and have a friend who is upgrading his or her Turbo's exhaust system and they will give you their old one. Some people have had fitting problems, but when I did this (before my custom setup) it fit perfect for me. Plus it sounded really good. But it wasnt giving me very good top-end torque, so I switched to the custom built setup. Personally I wouldnt do this unless it was free.
    • Get a high flow cat if you are worried about emissions, and run 2.5 or 2.75" pipe from there to your muffler. Otherwise, get a test pipe made and replace the cat with it. To do that, get a muffler shop to make you about a foot of pipe with two flanges on either end. Or you can shove a 2.5" pipe into your hollowed out cat. The main thing is to get rid of the stock cat. It's very restrictive.
  • Headers - AFAIK, there arent too many options here.
    • Doug Thorley - I have no first hand knowledge of this header but it's supposed to be the best one available.
    • Jim Hall - Supposedly these are perfect fits, port matched for better flow, and ceramic coated, but I cant confirm that as his site is rather vague. Obviously you can only get this from Jim Hall. I havent done any business personally with him, but I've heard good and bad things about him. His website is supposed to be here, but it goes down occasionally, an alternate here has pretty much the same stuff. *Recent news* I hear Jim Hall just modifies the Pacesetter to fit and is still as easy to get in contact with as Elvis. Pacesetter - I've heard good and bad things about them. My personal experience isnt too great though. They seem of solid design, but the flange that goes onto the exhaust ports has too much metal on it, so it doesnt fit. A little grinding will fix that. The paint on the header burned off in five minutes of installation, so if you get this header, dont install your O2 sensor until the paint has burned off. Moving further down the line, the collector tubes dont line up correctly with the remaining portion of pipe that goes to the cat. That needs be lined up correctly, and welded to keep a good seal. The second piece of the header is total crap. The pipe size is ridiculously small. I suggest getting a muffler shop to cut the pipe right after the two pipes on the Y join so that you can run no less than 2.5" from there to the cat. Also, the O2 sensor housing is way too far down the line. Its right next to the flange for the cat!! And there was metal in the way of the O2 sensor even fitting in the flange (a little bashing with a screwdriver fixed that). Since the N/A MK3 doesnt have a heated O2 sensor, you need to get a muffler shop to relocate the O2 sensor housing further up the line. I got all that fixing done at a muffler shop for $60. Also, its a good idea to have the header ceramic coated to keep engine bay heat down. This ceramic coating can run you $100-$200 depending on where you get it done, what particular material they use, and how they do it. A cheaper alternative will be to wrap the headers with exhaust wrap to keep the heat down but this may cause the header to rust quicker if not properly coated. ThermoTec sells wrap and some paint like coating to prevent moisture from getting in. It doesnt look as good as ceramic coating, but it's much cheaper. A piece of advice though, use gloves when installing header wrap. You could go without coating or wrapping, but engine compartment heat will rise enough to downgrade performance.
    • Paeco - I have no knowledge of this header other then that it exists.

Intake

• Air Filters
  • K&N FIPK - almost everyone has this filter, domestic and import owners alike. It flows very nice, looks good, is reusable, and gets rid of the airbox (a major airflow restriction).
  • Apex-I Super Intake - not too many people have tried this one. K&N is just so well known. Its very similar to the FIPK, but it has a extra filter area in the front of the filter, whereas the FIPK just has a chrome plate. This could be bad for performance as it reduces the area inside the filter, and creates turbulance. They are also reusable like the FIPK.
  • Blitz SUS Power - It is stainless steel mesh, so it gets my vote for coolest looking. It will not filter well. This filter is reusable.
  • HKS Super Mega Flow - this is a foam type filter. They have been known to fall apart (very bad). The general consensus is that it flows better than the FIPK, but filters horribly. People with SMF's can expect to find lots of grime in their intake tract. They are also not-reusable.
  • Greddy Airinx - this is also a foam type filter. Unlike the HKS unit, it is cleanable. They dont have a listing for the MK3 N/A on their website, but I know one of them will fit the N/A. I am pretty sure the one for the 2nd gen RX7 will fit. My K&N FIPK fits the 2nd gen RX7 as well as the 86.5-92 N/A's. This foam filter is extremely cheaply made. It looks like packing foam and glue.
  • K&N dropin - this is meant just to replace the stock airfilter. It doesnt replace the stock airbox like the above do, but its about 1/4 the price. If you are on a tight budget, this is probably the way to go. You can remove the stock airbox and attach the filter directly to the AFM. Most people just cut the airbox so as to leave just enough to hold the airfilter in place.
• Cold Air Mod
  • Get some kind of rubber or metal hose that will flex in 3" diameter. Any rubber house in your area should have 3" rubber hose. Pep Boys sells a plastic hose with metal rings in it that bends really well. You can get metal flex hose from a home repair store. You will also need some locking ties to hold it in place.
  • Since N/A's are made exactly like the turbo's just without all the turbo equipment, we actually have two places to run a cold air hose into the air filter so you may as well run two hoses. This mod works best with the air box already removed (works good with the FIPK installed). You'll notice on the left side there is a little black or gray plastic panel with some wires coming from it. You can remove that panel and run a cold air hose in through there. I ran one hose from the lower grill and one from the upper grill. Removing the engine cover on the passenger side under the headlight will give you more room to work with.
  • You can also go a little further and isolate the AFM/air filter from the rest of the engine bay with sheet metal or something that will block off alot of heat. Wrapping or ceramic coating all the intake piping will help too.
• Intake piping
  • The purpose here is to get rid of the stock intake resonator. This will increase air flow a little, to make the engine bay look better, and you may hear more air noises. The cheap way will be to just buy a section of 3" pipe from a muffler shop. Trim the first rubber intake hose so that the ribbed section is gone. You may have to trim a little more off to get the pipe to fit inside it. Before cutting the smooth section, try to stretch the rubber hose and then putting the pipe in. Make sure the AFM will also fit inside the rubber hose. WD40, or some kind of lubricant may also come in handy here. After you get that to fit, shove the metal pipe into other small curved section of rubber hose that fits on the throttle body. Getting new hose clamps will make it look so much better. Check out my finished product: Cant beat this for $15!
  • As a variant, you can get a muffler shop to mandrel-bend the 3" pipe so it curves instead of using the end rubber hose. If you do that, you will need to get a small section of rubber hose to connect the throttle body to the pipe. This will flow a little better, but someone who can do mandrel bending is fairly hard to find.
  • There are companys out there that sell pre-made intake pipes. Joe (last name undisclosed) tells me the 94-00 Civic will fit with very slight modification done with a Dremel. Cut off 5" and it will fit perfect. He bought his for ~$50, see a picture here There is also a particular year Accord that will fit, but doesn't look as good IMO.

Free mods (or nearly free)

• Fuel mods - The AFM is set for the factory specs. After you've done intake and exhaust mods, you may or may not need more fuel. There is a good tech tip on how to do this here I recommend having some sort of A/F gauge to determine whether or not you need to do this mod. Running too much fuel will make you slower.
• Timing - Factory setting is 10btdc. If you run high octane gas, 91-93 octane, you can increase your timing to 14-16btdc. To do this, short the T and E1 in the diagnostic box (just like you're checking engine codes). Using a timing light, check your timing. It should be around 10 degrees. Now, loosen the screw on the distributor that allows it to rotate. While watching the timing, rotate the distributor until the timing reaches what you want. Then tighten the distributor back down. Its not recommended that you go over 14 degrees unless you have some way to see detonation or if you just don't care like me :) The stock N/A computer is very slow to respond to knock and increasing your timing that much can cause damage if you do not have an alternate means to pick up inaudible knock.
• Charcoal canister removal. The charcoal canister is the black cylinder that sits on the passenger side in the back of the engine bay. It filters excess gas pressure so that it can be vented to atmosphere safely. You can leave the line unplugged and very little gas fumes will come out. Or, if you are worried about fumes, run some more rubber line from there to a hole in the frame rail straight down from where the canister used to be. Its covered with a plastic cap. Remove the charcoal canister. Plug up the vacuum line that goes to the AFM bracket to the thermostat housing bracket to the throttle body. You might as well remove all those lines and plug it up as close to the throttle body as you can. This wont really do much except give you a little more space to put stuff (its a decent location for a PCV catch can).
• PCV mod - this isnt much of a hp mod, its more of preventive maintenance. Normally, excess crankcase pressure is vented through the PCV "system" into your throttle body. This is mostly oil vapor which will coat your TB and intake manifold. Basically find a catch can like Jegs or a really slick unit like GReddy's. Run the hoses that go from each of the cam covers into the single line into the TB to your catch can. Make sure you plug up the TB hole. You dont want any air leaks. Some people have put little K&N breathers on the valve covers, I tried this and made a huge mess. I don't recommend trying it.
• EGR removal. Once disabled it should stop dumping exhaust gasses into the intake. It's easy to disable, just pull the vacuum lines off it. The best way to do it however is to completely remove the system. It's pretty hard to do without removing the head so you might want to wait until you have the head off for some other purpose. You'll just need to remove everything connected to the EGR and put a block off plate on the back of the head and another plate on the intake plenum. John Lunsford sells a decent set of block off plates, or you can make your own easily.
• Short shift mod - ok, so this isnt a hp mod, and it can be done before anything else, but its just so cool I had to put it here. Go here to find out how to do it. While you're at it, get some Redline Lightweight Shockproof tranny fluid. Drain the old tranny fluid and pour the new stuff in the shifter hole, be careful not to spill in your interior, tranny fluid smells. Shifts will be smoother with the Redline fluid, and your tranny will last longer. Redline MTL is also a good fluid if you can't get the lightweight stuff. An alternative to the SOGI short shift is to buy a real short shift kit like the C's or the Supra Sport unit. Shifting with a real short shifter is much nicer, I've run both types and the real short shifter feels and shifts much quicker.

Fuel Control Electronics - if you're serious about getting maximum performance out of your N/A you will need some sort of fuel control device along with a few gauges.

• GReddy e-Manage - the king of all piggy-back style electronics. It will modify your fuel delivery via AFM and via direct control over injector duty cycle. It can also modify timing, data log, etc. You'll need either a laptop or a GReddy e-01 to control it. The e-01 will also datalog extra information so I'd recommend getting one. One of the best things about the e-Manage is all of it's maps are 16x16, that means you can control fuel and timing at different RPM's and vacuum points. All the other piggybacks tune only wide open throttle and low throttle.
• A'PEXi S-AFC - mid-grade AFM based fuel modifier. Has a few bells and whistles, looks flashy.
• HKS S-AFR - cheapest AFM based fuel modifier on the market. Very simple to use and effective. No bells and whistles at all, just a good solid unit.

Gauges - I'm going to list by gauge type recommendation. The brand isn't as important, just remember you get what you pay for. I prefer GReddy gauges, but there are other good ones out there.

• A/F (Air Fuel) - one of the most common gauges out there. Most of them just read off your stock O2 sensor which is NOT accurate, all narrowband O2's are inaccurate. Examples of this type of gauge is Autometer, Cyberdyne, K&N, etc. GReddy makes a very accurate narrowband gauge, however it needs to be professionally calibrated to ensure accuracy. You can pretty much be sure if the gauge isn't over $300 then it's not wideband. FJO and AEM both make good wideband gauges.
• Boost/Vacuum gauge - this is actually a handy gauge to have on a normally aspirated car. Knowing engine vacuum will tell you how healthy the motor is, and if there's a problem you can sometimes determine it by the amount of vacuum. You can get away with a really cheap one if you want.
• EGT (Exhaust Gas Temperature) - not as useful as it is in a turbo car. It is nice to know but not vital.
• Fuel pressure - not really that useful.
• Oil pressure/temperature - both are moderately useful for knowing the health of your motor. Stock oil pressure gauge is inaccurate and very slow to react.
• Water temp - very useful since the stock gauge is horribly inaccurate.

Ignition - while the turbo's ignition system is pretty decent, the n/a's can use some improvement once you've done all the bolt-ons. On the dyno I gained no power with the ignition on or off with my mods. Checking for increase in spark it was VERY noticeably stronger with the HKS unit but there was no extra power to be had. There are many choices here since its pretty much all universal. All of them except the HKS system require a tach adapter and a extra high performance coil.

• Ignition control
  • HKS Twin Power - While this one is initially the most expensive, you wont need to buy more stuff to make it properly work with the Supra. It taps two wires off the coil and then has a ground wire. Very easy to connect and you can unplug it if it were to ever malfunction.
  • Crane - Crane has a few different models. Pretty much any of their Fireball HI-6 series are good, depending on what features you want. Surf their page for more info. Once you install this unit, if it malfunctions your car won't run.
  • MSD - MSD has a few different models you can use. Pretty much any of the 6 series are good, depending on what features you want. Surf their page for more info. Once you install this unit, if it malfunctions your car won't run.
  • Jacobs - Having not heard much about them, I cant really say much about them. I do know they have ignition system for the Supra though. Once you install this unit, if it malfunctions your car won't run.
  • Accel - Accel makes a pretty decent coil you may consider if you get one of the other ignition control units that require one.

• Ignition wires
  • Crane makes a few different sized wire sets. Their wires are black.
  • Magnecor makes a set 7, 8, 8.5 or 10mm wires (black, blue, red and red respectively). I have the KV85's (8.5mm) and highly recommend them.
  • MSD makes a set of 8.5mm wires. Their wires are red. Some people complain about the quality of these wires, some people love them.
  • NGK makes a set of 8mm wires (could be wrong about the size). Their wires are blue.
  • From what I've heard, Jim Hall makes some really nice wires for the n/a MK3. Less resistance (good thing) than all the other wires. Some people have had problems with the boots on his wires though. As mentioned above, it's not advisable to try Jim Hall.
  • The stock wires are pretty decent, but if you're stretching for hp, you might as well upgrade.

• Spark plugs - general consensus is that the stock ND (nippodenso) plugs are good. NGK's are decent also, if you can't find either you can try Autolites which seems to work pretty well. Get copper plugs for more spark, platinum for more life, iridium if you've got money burning a hole in your pocket. At less than $2/each I recommend coppers. Do NOT get any Bosch plugs.

Rotating mass weight saving - eliminating rotating mass is good for torque.

• Find a driveshaft company in your area. Just getting rid of the center support bearing is 5-10lbs! I had an aluminum one built by a guy in my town. Stock weighs ~34lbs, one piece steel ones geneally weigh ~22lbs, my aluminum weighs ~11lbs. Sometimes you can find various people selling them on the net, you just have to search around.
• Lightweight rims - Lightweight rims are a big help as the stock rims weigh a lot. The 3rd gen RX7 has lightweight rims on it that will fit on the Supra and can also fit a wider tire for more traction.
• Underdrive/lightweight pulleys
  • Unorthodox Racing Underdrive Pulley - These are the only underdrive/lightweight pulleys I've heard of for the Supra. This is actually a bad mod for your engine. The crank pulley acts as a harmonic dampener, and the Unorthodox pulley has no such thing. This will tear your engine up eventually. A possible cure for this is to have your engine perfectly in balance.
• Electric fan - Perma-Cool makes a fairly cheap electric fan that moves lots of air and you can wire up a cut-off switch. I recommend the adjustable thermostat or a thermostat from another company as the fixed 170F thermostat is a poor design. Black Magic, Hayden, Be-Cool, Flex-a-lite all make fans that will fit but I highly recommend the Perma-Cool over those. Anyone who makes a 14" or 16" fan will work on the Supra just so long as the CFM is high enough. The ability to force the fan on or off is great for drag racing and cold winter days. If you're going to be forcing the fan off you'll want to make sure you have an aftermarket coolant temp gauge, the stock one is useless.
• Lightweight flywheel - this is probably the hardest mod to install in the weight saving section as you need to drop the tranny to do this. If you are doing this mod, you may as well replace your clutch if you havent in a while.
  • Unorthodox Racing makes a lightweight steel flywheel for the Supra.
  • Fidanza makes a really nice 10lbs aluminum flywheel with replaceable clutch area.
  • HKS used to make a lightweight steel flywheel for the Supra. Maybe you can get lucky and find one.

Clutch - with increased power, your stock clutch is gonna start slipping.

• ACT makes a full faced organic, a 6 puck and a 4 puck clutch. 6 puck and 4 puck are unsprung and definitely for race applications only.
• Scott Mech used to make nice clutchs for any Supra. He'd custom make it to whatever driving needs you have. Its about the cost of any other good clutch, depending on application. However I don't know how to get in contact with him anymore.
• RPS can make a clutch for the N/A Supra. Alamo Motorsports sells RPS and might be able to help. The TRD clutch is just a stage 2 RPS. I'm currently using a RPS Stage 3 with no problems. Pedal feel is slightly stronger than stock. Stage 2 is upgraded pressure plate with organic disc and the Stage 3 is upgraded pressure plate with 6 puck sprung alternating carbon fiber and copper. It will chatter a little after completely broken in but it's not nearly as bad as the ACT 4 or 6 puck.
• SPEC makes a few nice clutchs for the W58. Adam Hintgen had great luck using them on an N/A tranny with ~450rwhp (turbo conversion).
• Centerforce seems to have a bad reputation around the Supras group, but around the domestic groups Centerforce is well thought of. I had a Centerforce Dual Friction in my car for a while, and after about 5000 miles it just stopped gripping. Pedal feel is just like stock. Centerforce makes 3 different clutches for the MK3 N/A. They have the CFI rated at 30% more grip than stock, the CFII rated at 60% more grip than stock, and the CF Dual Friction rated at 90% more grip than stock.

Adjustable Cam Gears - you can get a few hp out of ACG's. You will need a dyno to tune them correctly. You can use gears from a 7mgte or 7mge.

• HKS made a ACG for the 7m series. It was discontinued.
• AEM makes an ACG that works well, available in three colors. Some people have had slipping problems with them at high revs but supposedly AEM has changed their design. Alamo Motorsports sells AEM.
• TRD (Toyota Racing Development) also makes ACG's for the Supra.
• Unorthodox makes a decent looking set available in 3 colors.

Cams - I don't know of any pre-made cams for the 7mge. You can use 7mgte cams but they won't be designed for normally aspirated use. Companies like Crane will custom grind a cam to your specs. Some will even recommend a particular cam grind.

Internal Engine mods - these are general internal engine mods, I.E. they work for any car.

• Porting and Polishing - increasing flow increases efficiency.
  • Pretty much any port and polishing shop can work on the AFM, throttle body, intake manifold and exhaust manifold. You may want to take your cylinder head to a reputable shop in your area.
  • Gude Performance sells a ported and polished head for the Supra. I dont know of anyone who has used these people.
  • Extrude Hone will do a seriously bad-ass job of making everything flow better. They run an abrasive liquid through intake manifolds, exhaust manifolds and your cylinder head. This can get expensive real quick. $365-675 for the intake manifold/throttle body, $500 for the exhaust manifold, and $900 for the cylinder head. Personally I wouldnt spend that much money, but it you really need more speed....
• Increasing compression - there are a few ways to do this. Anyway you do it, you'll have to take the cylinder head off, so you may as well put a MHG (metal head gasket) in.
  • Mill the block to max spec, try to take a minimal amount off the head so you don't change the combustion chamber shape. To install a MHG you'll have to mill both to make them flat and smooth.
  • Get compression increasing pistons. This is probably a better way to go, albeit a little bit harder to install.

MHG (metal head gasket) - with more power, you will put more strain on your motor. HG's are a known weak point on the Supra. Even N/A's have this problem. If you can tune your car very well or aren't running increased compression you can probably run the OE HG with ARP head bolts and never have any problems.

• GReddy makes a 83mm (stock) and a 85mm bore the following thicknesses : 1.0mm, 1.5mm and 2.0mm
• HKS make a 86mm bore in the following thicknesses : 1.0mm, 1.2mm (stock), 2.0mm and 3.0mm

Suspension - besides helping your launch, an upgraded suspension will give you lots of fun.

• Coil-Overs can be expensive, but for AutoX and Road Racing there is no alternative. You can use coilovers from a JZA70, MA70 or MA71 chassis.
  • Cusco makes a few different sets. I don't know much info about them.
  • HKS makes a set. 25 way adjustable, both rebound and compression. Corner height adjustable. Alamo Motorsports sells them.
  • Tein makes a few different sets. The Flex are 25 way strut rebound and compression adjustable, corner height and spring pre-load adjustable. The Flex coilovers are meant to be used on daily driven cars, they are soft enough for daily driving but handle like coilovers. Tein RA and HA are strut adjustable and corner height adjustable but are meant for racing only, they're too stiff for daily driving.

• Springs - there are two basic types, progressive rate and linear rate.
  • ST (Suspension Techniques) makes a linear rate spring. They will work great for about 2-3 years before the rears start to sag (recent design change may have fixed that).
  • Tokico makes a linear rate spring. They recently changed their design and now the fronts will sit a good 1" lower than the rear causing excessive scraping and general annoyance at the un-levelness of the car. Spring spacers will solve this.
  • Eibach makes a progressive rate spring. Very choppy/bouncy feeling unless you have a really serious strut. These springs may prematurely ruin a weak strut.
  • TRD makes a progressive rate spring.
  • Intrax makes a progressive rate spring.
  • GReddy makes a progressive rate spring.
  • H&R makes the worst set of springs I've ever seen. Weaker than stock these springs will slam your vehicle onto the ground and tear up your undercarriage.
  • B+G (B&G?) makes a crappy set of springs also. A couple years ago I had the opportunity to put them on my car for free but after seeing that I could compress them 50% by hand I passed on that deal. Supposedly they have changed their design.
• Struts - if you have TEMS and want to keep them, you'll need to get TEMS replacement struts (i.e. Tokico Illumina II). Otherwise enjoy the money saving and get non-TEMS.
  • Tokico makes TEMS (Illumina II) and regular (HP) struts. In my opinion they are the best struts you can get for the price.
  • ST makes non-TEMS struts.
  • Koni makes a manually adjustable strut. Pretty beefy and a good alternative to TEMS.
  • TRD makes non-TEMS struts.
• Anti-Sway bars - this is probably the most enjoyable suspension item. Installation of a good set of sway bars will keep the car from leaning so much in turns making weight transfer faster and allowing you to corner quicker.
  • Addco makes a set.
  • Cusco makes a set which have the same specs as the ST's except for metal content which is unpublished. They sell for about 2-3 times as much as the ST's.
  • ST makes the most commonly used sway bar. I've been using them for no years with no complaints.
  • Whiteline makes the biggest sway bars for the MA70. I have no first hand knowledge of them but hope to try them soon.
• Upper Pillowball Mounts
  • HKS makes a set of purple anodized front and rear, TEMS compatible with some customization.
  • Tein makes a green set.

Email me bishop@ma70.com

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