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SR20DETs

"Red-Top"+ S13 Motor / Early Model 180SX Motor+ 205 hp @ 6,000+ 203 ft.lbs @ 4,000+ T25 Turbo+ Called a Red-Top because of its deep red valve cover

"Black Top (S13)"+ Late Model 180SX Motor+ 205 hp @ 6,000+ 203 ft.lbs @ 4,000+ T25 Turbo+ Same thing as a Red-Top but newer and has a black valve cover

"Notch Top / S14 SR / Black Top"+ S14 Motor+ T28 Ball Bearing Turbo+ 220 hp @ 6,000+ 203 ft.lbs @ 4,800+ Called a notch top b/c of the variable valve timing bulge on the valve cover, valve cover is also black

"S15 Motor"+ S15 Motor+ T28 Ball Bearing Turbo + 250 hp @ 6,000+ 6-Speed Tranny

"GTi-R Motor"+ Sunny GTi-R Motor+ Garret T28 + 227 hp + Individual Throttle Bodies+ AWD layout... meaning its FWD when swapped.

Modifying the SR20DET

When modifying a turbo motor the first thing that comes to mind is raising the boost. There are several things that must be taken into account for before you raise the boost.

1.) Verify the engine is intact and still has good compression via a leakdown test. 2.) Break the motor in for at least 500 miles on stock boost before you begin the torment of raising it.

After those steps we can assume, for the purpose of the FAQ, that we have a healthy stock SR20DET.

3.) Fuel ... stock fuel injectors are 370cc and can hold the general 1 bar of boost, however upgrading to larger injectors isnt a bad idea and is a must for a larger turbo. Keep in mind that the SR20 uses SIDE-FEED and not TOP-FEED Injectors. For 1 bar of boost it is required that you upgrade the fuel pump to a 190/255Lph Walbro or a 300Z TT Fuel Pump. The 300Z Fuel Filter also is a very good and cheap mod. Keep in mind you dont absolutely need a 255Lph fuel pump ... it supports 490 hp. You can save 20 bucks and get a 190Lph fuel pump that supports 425 hp.

4.) Intercooler (FMIC) ... a proper intercooler such as the Blitz LM or GReddy V or R SPL FMIC will provide a much lower boost temp which will allow you to safely run higher boost levels detonation free. The stock intercooler should not be trusted above 10 psi.

5.) Exhaust (Cats, Cat-Backs, and Downpipes) ... exhaust helps the turbine breathe more effectively and will thus help spool-up because the backpressure is reduced considerably. Exhaust also plays a role in cooling the turbine to safe levels because it allows exhaust gasses to transverse the turbine faster and more efficiently. A 3" exhaust is the standard for SR20 catbacks and downpipes. If you find it necessary to utilize a catalytic converter then you may have to check it once a month to insure it hasnt become clogged with unburnt fuel. A clogged cat can cause excessive backpressure and can create several problems. A test pipe will net you good horsepower gains and a better spool-up with the cost of low-end torque.

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Gauges ... a boost gauge is essential from now on. This is to ensure you are running the correct boost. Other gauges include EGT, Water Temp, Oil Temp/Pressure, etc. Those are nice to have but arent 100% necessary until you upgrade the turbo.

Clutch ... the stocker wont handle the upped boost very well. Its advised you upgrade to a good aftermarket upgraded clutch.

*------------------------*Now that we have a well fed, chilled, and breathing monster its time to up the steroids.

6.) Boost Controller ... SCC recently tested boost controllers and the cheapest electronic one was the best and the easiest! The greddy profec-B was the best unit tested. I would suggest buying either the Profec-B or a Blitz Dual Solenoid ID series controller to avoid boost spikes (over boosting) and turbo damage. The Boost Controller works by controlling the wastegate solenoid which controls the wastegate whos job is to divert gas to or away from the exhaust turbine.

7.) Turbo Timer ... before the boost wasnt really enough to justify a turbo timer because a simple 20-40 seconds of idling before you turn off the car would suffice. Now that you are pushing the turbine to its effective limit you will need to always remember to let it cool to avoid oil coking and bearing damage. The easiest way to do this is to have a turbo timer installed. It allows the car to run with the key out of the ignition for a set time.

8.) A/F Controller ... this will be a key tool later on in the game. It allows you to change your fuel enrichment levels and to notice rich/lean areas and correct them. Its a good failsafe tool and allows you to gain a few HP and prevent detonation due to lean conditions.

9.) Radiator ... this would be a good thing to replace so that your $2000+ motor doesnt go to scraps. Units can be had out of Silvias, Single Turbo Mk. III Supras, Turbo Volvos, and other cars. You can also purchase a Greddy, PWR, or custom radiator which will look awesome and provide better cooling than the other OEM units.

10.) Turbo Upgrade ... Several to choose from in this catagory. Ranging from GT2530s, T28s, GT2835s, even up to the huge T66 and T72s. There are several things to look at when selecting a turbo. Compressor wheels and exhaust turbines should be withen similar specs ( the exhaust turbine should be about 1.1-1.4 times larger than the compressor ), this ensures quick boost response and optimum efficiencies for the compressor. Different turbos also support different Hp levels... a GT2835 supports around 380-410 hp depending on the trim and a/r ratios that you select. A/R ratios are a measurement of the housing circumference vs. the radii of the wheel. A .54 A/R will have a quick spoolup but will have less flow top end. A .84 A/R on the other hand will spool a little slower and provide good flow top end. A 1.04 A/R will spool even slower and provide even better top end flow. Its all a choice you will have to make ... lag vs. top end power. Larger turbos such as the T66, T72s, and anyone sick enough to use a T51R or a T88H will require the use of nitrous to spool them anytime this century. Compressor trims move the efficiencies around on the maps. A higher trim will have better top end turbine speed efficiency (meaning more efficiency at higher boost) but often can mean more lag because of lower efficiencies at lower speeds. A lower trim will have good efficiency down low when boost begins and is near top boost but will fall off a bit when max boost is achieved (assuming you exceeded the compressors range, (ex. Stock SR T25 pushing 16psi).

Items incured with turbo upgrades: 1.) Manifold2.) Turbocharger3.) External Wastegate (unless an internally wastegated turbo is selected)4.) Larger Injectors (Ex. Nismo 555cc, again this is a sidefeed system)5.) Downpipe may or may not have to be modified6.) Stronger Pistons/Rods (a good idea if exceeding 350whp)7.) Metal Headgasket (a good idea if exceeding 300whp) 8.) Larger MAS (Z32 or Nismo, via Re-map or S-AFC) or a MAP Sensor (via Standalone)9.) Standalone Management or ECU Re-Map 10.) LSD and Wider Tires 11.) A few other misc. peices12.) For larger turbos an oil cooler wouldnt be a bad idea13.) Sleeving the Block for 400rwhp or more

10.) Some Other Mods ... 1.) Port, Polish, Extrude Honed Intake Manifold or Aftermarket Manifold2.) Port, Polish Head3.) Camshafts4.) Nitrous5.) Nitrous Intercooler Fogger System6.) Water Spray / Alcohol Spray 7.) Water Injection8.) Larger Exhaust 9.) Stroker Kits 10.) Sleeving the Block 11.) Lightwieght Flywheel12.) Multi-Plate Clutches13.) Aftermarket LSDs14.) Single Peice Aluminum Driveshaft15.) Upgraded Halfshafts

ETC. ETC. ETC.