SR20 Engine Upgrade Guide

[Ace]

Has your KA finally put you to sleep, or has the tired/slow revving truck motor seen better days??? If so, than you’re probably looking to take the next step in power, (and no, it’s not KA-T) which is obviously the SR20DET!

Just like the KA-T guide, this list is one primarily there for you to make the final call on what parts you decide to use on your car. I’ll try to provide basic info and give proper examples, but ultimately it’s your pocket book that is going to determine what part you get in the end.

This also isn’t intended to be a guide on how to swap one into your car. I will provide those links in the engine section below.

Now, on with the juice!

ENGINE: SR20DET

First off, we’ll start with some specs on the different engines and the sort (Sourced from Heavy Throttle)

*S13 Redtop Engine*
180SX 91-93 and Silvia 91-93
Displacement: 1998cc (2.0 liter)
Cam type: DOHC 16 valve, chain driven cam sprockets
Bore and stroke: 86mm x 86mm
Compression: 8.5 : 1
Horsepower: 205ps at 6000rpm Torque: 203 ft/lbs at 4000rpm
Stock boost: 7 psi
Throttle body bore: 60mm
Turbo specs: Injector size: 370cc/min
Compressor: T-25, 60 trim 56mm BCI-1 compressor.
Turbine: T-25, 62 trim 53.8mm 0.64 A/R turbine housing.

*S13 Blacktop*
180SX 94-98
Displacement: 1998cc (2.0 liter)
Cam type: DOHC 16 valve, chain driven cam sprockets
Bore and stroke: 86mm x 86mm
Compression: 8.5 : 1
Horsepower: 205hp at 6000rpm Torque: 203 ft/lbs at 4000rpm
Stock boost: 7 psi
Throttle body bore: 60mm
Turbo specs: Injector size: 370cc/min
Compressor: T-25, 60 trim 56mm BCI-1 compressor.
Turbine: T-25, 62 trim 53.8mm 0.64 A/R turbine housing.

*S14 Notch top*
Silvia 95-98
Horsepower: 220hp at 6000rpm Torque: 203 ft/lbs at 4800rpm
Turbo specs:
Compressor: T-28, 60 trim 60 mm BCI-1 compressor in T-04B housing
Turbine: T-25, 62 trim 53.8mm 0.64 A/R turbine housing.
Center Section: Ball Bearing
Variable valve timing system and a different turbo are the significant changes from the S13 SR20DET engines. S14 uses 'low port' intake design vs. S13 'high port' design.

*S15*
S15 Silvia 99+
Horsepower: 250ps at 6000rpm Transmission: 6 Speed, Close Ratio
Injector size: 480cc/min
Turbo specs:
Compressor: T-28, 60 trim 60 mm BCI-1 compressor in T-04B housing
Turbine: Inco turbine wheel. Cast divider wall between turbine discharge and wastegate.
Center Section: Ball Bearing
Additions: 6 speed manual transmission. The 6 speed cannot be used on the S13 and S14 motors, and uses a different driveshaft. Speed sensor is located in the differential.

As with all engines, the newer the better when it comes to the SR. This doesn’t mean that the s13 redtops are bad engines, it’s just that they are slowly becoming older and older, hence making it more of a requirement to rebuild all s13 engines, or at minimum change seals and bearings, but you should do this even with newer engines.

With the SR becoming more and more popular, the sources for engines have increased ten fold. With this increase however, comes the countless scams that can be found online and especially on eBay. While we’d all love to find a ‘perfect low mileage’ redtop for 1300, it just doesn’t happen. While deals can be found/hand, it’s more than likely that you won’t find a complete redtop motor set for less than 2,000 dollars. Obviously you may be able to purchase them junk and rebuild them for less, but this is just a ‘ballpark’ estimate for a true ‘drop in and go’ engine.

With all JDM engine swaps, it’s usually a case of high cost=high quality. Because of that, the following places are the ONLY places you should get your engine from. These places all have great customer service, and will not lead you wrong:
1.Heavy Throttle, of New York ( [Only Registered Users Can See LinksClick Here To Register] )
2.Phase 2 Motortrend, of Southern California ( [Only Registered Users Can See LinksClick Here To Register] )
3.Enjuku Racing, of South Florida ([Only Registered Users Can See LinksClick Here To Register] )
4.SR20Store, [Only Registered Users Can See LinksClick Here To Register]

Again, while there may be others that are good, these 3 are time tested and proven to deliver the goods.

As with all engines, I highly suggest purchasing an OEM gasket rebuild kit for both top and bottom ends. New OEM bearings are another thing to replace. Other things to change while the engine is out of the car are the water pump and oil pan.

SWAPPING KA FOR SR
Again, I said earlier that this wouldn’t be a swap guide, mainly because there are already good ones out there. Below is a list and description of where to go for what when it comes to your engine quest: Probably the best swap guide on the net, direct from Heavy Throttle: [Only Registered Users Can See LinksClick Here To Register]

TURBOCHARGERS:
As the quest for more power continues, one of the next stops is upgrading turbos. With proper mods, S14 T28’s are known to put cars into the 270 whp category, however some people will still thirst for a faster car. S15 Silvia turbos could put 300whp with equal mods.

Now if you’re looking for something aftermarket, and or new, there are many good options. For those looking to stay t2 based and retain stock manifolds, there are 4 (well 5 kind of) great upgrade turbos: HKS GT-RS, Garrett GT28RS (Disco Potato), and the newcomer, Garrett GT2871r (Either .64 or .86). The HKS GT-RS and the Disco Potato are fantastic torque monsters, and are noted for their lightning spool ability. Fun street turbos, these will give approximately 320-330 peak power with appropriate mods at 18-20 psi. Not a lot, however it’s the instant spool ability that sells these turbos. 10 psi on a disco will eat up 12 on a t3/t4 ka, simply because of response.

The 3rd turbo (or 3rd and 4th) is the GT2871r. Now the .64 turbine version is slowly becoming the logical upgrade over the 28RS, as it provides damn near similar spool time, however where the disco falls of at 6000 rpm, the 2871 pulls hard to the limiter. With proper setups, the 2871 .64 is putting down between 360-380 whp at 18-20 psi. This translates to high 11’s on street tires in the 1320. The big brother to the .64 turbine is the .86 option. This turbo has a slight bit more lag/onset than the previous 3 (still not as bad as a t3/t4), but where this lacks in response, it makes up for in top end. 400hp whp dynos are common with the right parts. Lastly is the 3071r. This is the largest t2 available from Garrett. This will have similar lag to a t3/t4 setup, but provide more power than the 2871r .86. People looking for highway monsters, check here!

For those looking for t3 based turbos, there are many great upgrade choices. Obviously, the proven old guy of the group is the typical t3/t04e turbo. Found in countless varieties, it can be basically crafted to ones own personal taste. One of the most popular t3/t4’s out there is the Precision SC61BB. Regarded as the fastest spooling t3 hybrid, it’s proven to throw down huge numbers and make legends out of ‘wangan’ (highway) rollers. Fear not Garrett standbys: Garrett has just release ball bearing CHRA upgrades for those that already have old units. These upgrade options should make for VERY interesting times when those begin to convert over. GT3076 and GT30r’s also provide big power, and are great t3/t4’s for those with the peak power craving.

Again, while other turbos may be available, such as GT35, GT32, and T66’s the fact of the matter is that those going that route aren’t new guys, and have more than enough knowledge to go that far.

As before, purchasing a turbo isn’t tricky, but down to preference. Want fast spool, response and the ability to drop your sisters panties quicker than the football team captain, go gt2871r .64! Want power that will make you a highway KING, and get you pussy you never knew available before, follow the ‘go big or go home’ mantra and get yourself a SC61BB.

Interested in getting one, check out the following:
[Only Registered Users Can See LinksClick Here To Register]
[Only Registered Users Can See LinksClick Here To Register]

Also be sure to check other for sale forums for great deals on these turbos.

MANIFOLDS and TURBO EXTENSIONS:
Manifolds are always a topic of discussion for those looking for great power. Obviously manifold choice is co-dependent on turbo selection, so be sure to get the correct flanges for your setup. Those opting for t2 based fun; you can keep the stock OEM cast manifold on there for durability and proven performance. There are also countless bottom mount t2 tubular turbo headers to choose from. HKS, and JIC are many of the choices to go from. Remember, while Name Brand is proven to last longest without cracking, one can always opt for cheaper alternatives like the Megan racing if looking for the look, and bang for buck.

T3 based ballers will have to look no further than Full Race or Peakboost for manifold options. While pricey, they are both regarded as being the best.
Lastly, if you’re looking for aftermarket turbo extensions (also known as o2 housings, or J pipes), look no further than the Greddy or HKS housings. High quality, with split tracts for wastegate gas and normal exhaust, these units are dyno proven to be the best. Cheaper alternatives are available, but go with the best on this one.

[Ace]

DOWN PIPE AND EXHAUST:
Unlike other aspects of car parts, exhaust pipe generally is exhaust pipe, irregardless of price. HOWEVER there are differences, between mild steel (which will rust), stainless (which won’t rust), and Titanium systems. I’d suggest staying away from mild steel exhaust components, simply to stay away from rust. Titanium is also nice, but not worth the cost unless you are looking for FULL weight savings. 3” pipe is also a must (or bigger if possible) for the best gains from your setup.

Companies like RSR, HKS, and ApexI all offer fantastic systems that you can choose from. RSR ExMag’s are regarded as being the quietest of the bunch and offers the same performance as its’ louder competitors. HKS HiPower is regarded as being one of the louder setups in the bunch, so be aware for unwanted attention with this setup. Again, 3” is the main goal here, so sound aside, all systems are equal. Even the lesser priced Megan systems are great choices here.

WASTEGATES:
The simple choice for all external gate setups under 350whp is the awesome Tial Sport 38mm wastegate. Offered with many different boost pressure springs, its’ certainly the choice for average users, to those who compete on a serious scale. Turbosmart Ultragates also work wonderfully, but will cost you a lot more. There are also lesser cost alternatives, like those offered from Turbonetics…but simply put they are junk.

Those who t28 based setups with internal gates, will probably prefer to step up to an HKS actuator to ensure good boost levels.

Lastly, the question of open dump vs. reroute comes up. For those looking for the most power, you should dump into the open. The downfall of this way is the awful open exhaust noise. For those looking for a stealth setup, reroute your wastegate dump!

CAMSHAFTS + VALVETRAIN:
Cam’s are not only dependent on your power goals, but are also dependent on what SR you have. While S13 Redtop and Blacktop engines can run any cam combination desired, the s14 and s15 engines have VTC and require VTC friendly cams, or eliminating the VTC system altogether.

All things considered, and with many a dyno to back it up, Jim Wolf Technology ‘S3’ cams are by far the best all around cam for power. Providing awesome power all over the power band, this is considered to also be the most popular SR cam in the world (For both Turbo RWD and FWD SR, as well as N/A versions!!!) .Featuring .442” of lift, and a 260 degree duration on both intake and exhaust cams, it’s hard to beat. Again, that is my opinion only, so take it how you wish. Others believe S4’s are great turbo cams, but those who think that are also using t3 based snails.

Question for more top end power? Take a look into Jim Wolf “S4's” or “C1’s”. Also be sure to consider the HKS Step 2’s. When running certain high end cams, like the before mentioned, you also upgrade your valve springs and retainers to JWT, Grex or similar. All JWT “S” series cams are safe on stock valvetrain.

With all other things, there are still more options out there, but if you’re reading this you aren’t creating a world beater either (hey, we all have to be honest with each other ya know) Solid valvetrain kits are available, but certainly not for anyone’s daily driver. Jim Wolf Tech and Enthalpy have also both concluded that 7800 rpm is a sufficient redline for SR engines, therefore Raising it any higher would certainly require Rocker Arm Stoppers and a spring/retainer upgrade for their engines.

For the big cam list, as well as some comments from SR gods, click here: [Only Registered Users Can See LinksClick Here To Register]

[Ace]

ECU/ROM TUNES:
This is an area that can certainly be debated until the end of time. The two clear choices (and only choices IMO) are Jim Wolf Technology and RS Enthalpy. Clarke at JWT has been tuning Nissans longer than most of us have been alive, while Scott has been an SR20 mastermind for Southern Florida. It is known that Enthalpy tunes have across the board made between 15-30 more WHP peak than JWT tunes (who is on the more conservative side). Both options will work fantastic, are truly plug and play and is simply down to your personal choice.

Now there are always those looking for cheap ways (aka shortcuts) in their turbo setups. Enter the ApexI “Super AFC” and the Greddy “Emanage”. Both of these management options will work, but will require tuning in order to get the right result. Both options in my opinion are simply cheap ways out initially. Once people get them tuned ETC, it would have simply been cheaper in the end to go JWT or Enthalpy.

However, the SAFC can be used as great tuning tool in conjunction with a JWT ECU. Again, this will put your setup on the edge of fuel safety, but will get you the extra ponies you’re looking for.

Lastly, there are always standalone options. I’m not going to dive into these options, but you will undoubtedly get the most power from these avenues. AEM EMS, Haltech and the sort will require tuning (and some require complete rewiring of all factory wires.) This choice should be a choice for turbo experts, and are not something to even consider for a first turbo setup. Again, these options are very expensive and will need to be tuned.

FUELING:
Any turbo setup is need of a bigger and better fuel pump. As with 90 percent of all aftermarket turbo kits, the Walbro 255lph pump is the way to go. While some have used Z32 pumps and the sort, you can’t beat the reliability and results of the Walbro.

Injectors are narrowed down to pretty standard options. For those not wanting to upgrade fuel rails, stock injectors are the way to go for those staying below to stay below 250whp. Nismo 550cc injectors can be used for those looking to stay under 350whp. The main disadvantage of the larger side feeds is cost.

For those looking to upgrade fuel rails for larger more free flowing setups, there are 3 quality choices for those who are also upgrading to top feed injectors. Jim Wolf, JGY, and HKS offer awesome fuel rails for your platform. When using these fuel rails, you will need to also use top feed injectors, like the venerable MSD 50lbers and 72lbers. For those staying under 350whp, stay with the 50’s. For fewer than 450, use the 72’s.

As far as FPR’s, the NISMO FPR is the way to go when using JWT and JGY Rails. You can also use remote lined FPR’s such as Aeromotive units, but you will need a rail plug for the FPR spot.

MAF’s: The two most popular (and only options as far as I’m concerned) are the Cobra MAF and Z32 MAF. Both are fantastic, and both can be readily found or used. JWT Tunes use either choice, whereas Enthalpy uses Z32. Both are good up to 500+ hp, but the Cobra requires a special circuit for usage above 350whp.

INTAKE MANIFOLDS:
Once you crest that magical 300 whp mark with your SR, it’s time to begin looking at intake manifolds. Again, in the interest of cost and availability, the Greddy Intake Manifold is king. While JUN and other Japanese tuners offer upgrades, there are very few (if any) street driven SR’s using one of these manifolds. The Greddy manifold is both affordable and good looking, while at the same time fattening that turbo power band. While TopSpeed offers a knockoff, its construction is not equal to the Greddy manifold. With a HUGE plenum to help push that hot air in the engine, it’s the obvious upgrade when aiming at the 300+HP club.

BLOW OFF VALVES:
This is another option that rests on you the user! Things to consider are a BOV that recirculates, as that will work best on Nissans (or any MAF application for that matter). The Greddy Type S and new Type RS work fantastic as recirculation valves. The HKS Super Sequential now also has adapters to work in recirc applications as well.

INTERCOOLERS/HOTPIPES
Being that SR powered Silvia’s are so common for tuners in Japan, there are many I/C kits available to US customers with swaps. The most popular by far is the Greddy VSPL, as its great quality and great priced. HKS, and Blitz also offer fantastic intercooler kits. Going custom is always an option, but these kits are so well tested and designed that only a fool would pass up these.
Remember however, that when purchasing these kits, NONE of them come with hotpipes. Also take into consideration if you are running an aftermarket intake manifold, as you will need a special pipe to mate up with the manifold (Such as the Greddy coldpipe kit). While Greddy offers a 2” replacement for the OEM piece, other companies like Heavy Throttle and Enjuku offer aftermarket 2.25 pieces with the option of having BOV flanges pre welded on. You certainly can’t beat the price for a pre welded aluminum hotpipe. Remember though, GT2871r and GT3071r turbochargers will require a 2” to 2.25” elbow form turbo outlet to hotpipe to fit.

OIL PANS/COOLERS/FEED/RETURN
Being that the SR20DET is turbocharged factory, there is already OEM feed and return lines for those opting to stay with OEM t25 and t28 systems. Those who upgrade to GT28RS or above in the T2 family, or T3/T4 should consider the Taka premade stainless braided lines. They come with Earls fittings to boot.

Being that the SR is extremely oil dependent, Greddy has gone ahead and created a perfect cast aluminum option for upgrade. Being that it has a larger capacity and baffle plates inside to prevent slosh, its’ the clear upgrade on ANY engine swap. At bare minimum, at least change to a new OEM stock pan, as the one on the engine undoubtedly is bent from shipment. While cheaper knockoff parts are available, their poor construction and shoddy design have kept them from getting to popular. Some have even leaked through the pan itself due to the cast aluminum being to porous.

Oil Coolers are also another safety upgrade/mod for your engines. While Greddy and others offer sr20det specific kits, there is no reason on why it’s double the cost of the Earl’s Sport Compact cooler kit. Most prefer the Earl's kit due to cost and that it is custom fit for the car at hand. Greddy is proven to fit, but so have the custom Earl's kits for half price.

CLUTCHES:
This is another option to be left up to user. The best choice in terms of drivability with clamping force is the JWT Z33 Flywheel and Clutch. Yes, I did say 350z. The JWT flywheel has the holes for both applications. 1200 clamping force is awesome. Did I also mention it’s on a full sprung clutch DISC! Yes, no pucks here!

ACT Also offers great options in use with stock flywheel.

The biggest thing is your cash. I’d rather spend more money on the JimWolf Setup, and have a clutch nice enough for grandma to drive, rather than deal with the clattery mess we call 6 puck unsprung discs. Remember our cars are our toys, so there is no reason to be mad at ourselves by installing a race application clutch.

GAUGES:
The best option, for price and performance is Autometer. While others may be better, I just don’t see the reason to spend triple on a gauge. I’d suggest Boost Pressure, Oil Pressure, and Water Temp. There is no need for an A/F Ratio gauge when using a JWT or Enthalpy tune, however, for those who aren’t, the ONLY option to go is the PLX M300 or M500 Wideband system. The best part about this system is that the wideband sensor can be used in place of the stock sensor, while providing wideband output to your gauge and narrowband output to the ECU. DO NOT DO NOT DO NOT rely on a simple A/F gauge that you can get at AutoZone. They are nothing more than a fancy fireworks gauge with no precision.

EXTRA/TURBO TOYS:
As with any turbo setup, there are always little extras to make boosting even more fun. Electronic boost controllers are the most obvious fun toy, and the Greddy Profec Type S is the only way to fly. Upgraded radiators with electronic fans are another good upgrade, but not needed for normal boosted fun. Turbo timers also are nice functional little tools that work well.
While not part of the engine system, a Limited Slip Differential (LSD) would be another must have upgrade for your 240. 1.5 is best for street, while a full 2 way is best for drifters.
Lightweigh pullies and smaller pullies are also things to consider, or at least the water pump pulley. SR pumps can cavatate at higher RPM, so underdriving the pump will prevent this.

WOWZERS

Well that’s all I have at this point. I’m sure I’ll think of more later on, but this should give you a good idea of what to look for and what works. Obviously there are other things that you could add to this list, but I tried to keep it aimed at affordable items that anyone/everyone should have.
As with all engine upgrades, pleaes be sure that you are capable as a driver, and that your car is able to handle allt he power. No use in having 300 whp and oem discs up front and drums out back. Your car is only as strong as your weakest part, so if you have piss poor stock brakes, than your car will not live up to it’s full potential *Trust Me*. Nothinig is worse than hauling balls and not being able to bring it back down to a managable speed.
As always, happy boosting and enjoy the SR. With research comes knowledge, so never forget to read as much as possible about your new toy