HELP! Recently acquired CTSC kit from 2003-wanting to transplant in my 1995...HELP!

[charlee]

HELP! Recently acquired CTSC kit from 2003-wanting to transplant in my 1995...HELP!

I recently acquired this kit: http://www.nsxprime.com/forum/showthread.php/194706-Comptech-high-boost-S-C-set-up

and plan on running it in my 1995 NSX. My babied 100k motor is in tip top shape that has never been abused, tracked, or boosted. My car currently has the 99 headers, and a comptech exhaust. I consider myself an expert backyard mechanic since I have done sr20det, vg30dett, KA24DE, RB20DET swaps, umpties jobs of head gaskets, clutches, timing belts, and clutch and timing belt on my C30. So I am mostly confident with turning wrenches.


I believe this kit is the original Lysholm blower that came with the initial CTSC kits. I also believe it includes the 86mm "high boost" pulley. Below are evidence to suggest these assumptions.

AEM F/IC w/ Harness for 95-05 NSX (tuned for this set up by SOS)
Comptech fuel lines and rails with adjustable fuel pressure regulator
R/C 550 injectors
High boost pulley with correct belt
Comptech Targa Brace
Alternator w/extension
Brackets and pulleys
Lower intake Manifold
Lysholm 1600 S/C
All aftermarket bolts and Hardware (beside what is reused from OEM parts)

From seller: Checking out the SOS website and they state their high boost pulley's. The 86mm is 3.38inches and 91mm is 3.58 OPTIONS

Whipple-based pulleys available:
•86mm (Comptech "high boost")
1. 3.0L NSX: approximately 9 psi
2. 3.2L NSX: approximately 8 psi

Autorotor-based pulley available:
•91mm (Comptech "high boost")
1. 3.0L NSX: approximately 9 psi
2. 3.2L NSX: approximately 8 psi

•86mm (Comptech "higher boost")
1. 3.0L NSX: approximately 9.5 psi
2. 3.2L NSX: approximately 9 ps

In wanting to use all components coming from this kit, the SOS walbro 255 fuel pump NSX kit in my 1995 NSX:

What concerns should I have?
Are there other parts/components I have not considered?
Will I need a tune (since the seller's AEM F/IC has one on it for his 3.2 2003 NSX)

Your help and expertise much appreciated.

 

[Jinks]

Don't use the Walbro fuel pump. I'd get the supra denso pump. Or you can just buy the low boost components. But either way, tune it. I was wondering who scored that kit for sale. Looked like a sweet deal. I knew it would sell in hours. Which still goes to show, ct products are awesome and hold value just like our cars. Happy boosting, you'll love it.

 

[jwmelvin]

HELP! Recently acquired CTSC kit from 2003-wanting to transplant in my 1995....

I would put an AFR gauge in first thing. That's your front line for detecting problems. A logging setup is nice but you can log through the FIC (limited amount internally and more when a laptop is connected). Once setup I would look at the AFR with the existing tune and see how it looks. Creep up on engine load slowly. Sorry just realized you have an NA1. I would have it tuned. No worries to start it up and drive to the tuner. Best to keep out of boost and that's very important if you don't have an AFR gauge.

With the higher-boost pulley, your blower will generate more heat. That's the downside. A number of us use water or water-methanol injection to manage heat, even with the low-boost setup. I run around 7psi. Injecting water before the blower increases boost a bit (likely by reducing leakage in the rotors?) but uses a lot more water than injecting after the blower. Your setup is nearly identical to mine but I inject water before the blower and my motor is a NA2.

Edit: for the fuel pump, plenty of people have had good success with the Walbro. I used a Deatschwerks DW200 based on ddozier's recommendation. It has been perfect for me. If you have to replace the pump anyway, then I would probably use a new one since the labor is the majority of the expense. But I'm not clear that you have to. With the FIC and larger injectors, you don't have to run elevated fuel pressure so I imagine the OEM pump will work. Again, monitoring AFR is the key to knowing.

 

[charlee]

I would put an AFR gauge in first thing. That's your front line for detecting problems. A logging setup is nice but you can log through the FIC (limited amount internally and more when a laptop is connected). Once setup I would look at the AFR with the existing tune and see how it looks. Creep up on engine load slowly. Sorry just realized you have an NA1. I would have it tuned. No worries to start it up and drive to the tuner. Best to keep out of boost and that's very important if you don't have an AFR gauge.

With the higher-boost pulley, your blower will generate more heat. That's the downside. A number of us use water or water-methanol injection to manage heat, even with the low-boost setup. I run around 7psi. Injecting water before the blower increases boost a bit (likely by reducing leakage in the rotors?) but uses a lot more water than injecting after the blower. Your setup is nearly identical to mine but I inject water before the blower and my motor is a NA2.

Edit: for the fuel pump, plenty of people have had good success with the Walbro. I used a Deatschwerks DW200 based on ddozier's recommendation. It has been perfect for me. If you have to replace the pump anyway, then I would probably use a new one since the labor is the majority of the expense. But I'm not clear that you have to. With the FIC and larger injectors, you don't have to run elevated fuel pressure so I imagine the OEM pump will work. Again, monitoring AFR is the key to knowing.

Thank you. My 95 is obdII, so does this make a difference. Regardless, a tune seems to be most appropriate and mandatory? Most I've talked to recommend the walbro.

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Don't use the Walbro fuel pump. I'd get the supra denso pump. Or you can just buy the low boost components. But either way, tune it. I was wondering who scored that kit for sale. Looked like a sweet deal. I knew it would sell in hours. Which still goes to show, ct products are awesome and hold value just like our cars. Happy boosting, you'll love it.

Thank you, how much for the denso pump?

 

[Jinks]

I think the denso oem supra pump runs about 260. I do not run one, but have been told to run nothing but that on high boost. Also, Jwmelvin knows his shit about the ctsc.

 

[RYU]

Denso (Supra), Deutschewerks, or Aeromotive all make good fuel pumps. I run the Denso "Supra" pump but it's a relative dinosaur by today's standards. It draws a lot of amperage but it's consistently tried and true and bulletproof. I have very very strong hate for the Walbro 255. Not only are there a lot of fake 255s but mine failed less than 1yr. After learning new curse words by having to remove the gas tank for a 2nd time I will never use a Walbro 255 again. FWIW, apparently their newer generation pumps are better.

Managing heat can be approached in stages on the CTSC. I track my car under insane heat loads and the water/meth solution (see my build thread below if interested) has worked amazingly well. It also has a nice side effect of keeping your engine free of carbon deposits. The methanol and H2O steam acts like a cleaning agent. Cooling is not necessary for safety if your F/IC is tuned properly. However, to prevent heat zapping power loss, you need some way to cool the IAT. I would recommend you don't tune for meth. This means do not have your timing tables rely on the methanol octane. This way, if meth runs out or a pump fails or whatever, your F/IC will read high IATs and pull back the timing safely. jwmelvin's solution allows the use of the factory OEM cover. However, if you spray post blower you cannot. I've found spraying post blower is most efficient by using less water/meth and cools more effectively, but you need to be careful about where the spray nozzles are positioned in the charged air. At your high boost levels, having an equal spray of meth/water into each cylinder is even more important. Spraying pre-blower allows for the best mixture but it also heats up the water/meth molocules and there is debate about the meth eating up the supercharger twin screw coatings. If I had your car, and it's a street car, i'd get everything installed. Get it tuned by a talented tuner (worth their weight in gold) and let him know you might decide to spray ONLY water later on. Move forward from there...

You can also run an aftercooler. It is more complex. More expensive and certainly heavier if weight is a concern. In prolonged aggressive driving it will heatsoak and it does rob the car of some boost pressure as well. The way the aftercooler is sandwiched only exposes half of the heat exchanger to be cooled. If it the heat exchanger core fails it will introduce coolant into your combustion chamber. Though it has it's advantages. It's a set it and forget it solution (don't have to constantly fill the methanol/water tank) and for a street car it's a effective solution. You cannot use the OEM engine cover with this solution as well.

Lots of pros and cons when it comes too cooling. There is no one perfect solution on the NSX. Lots of knowledgeable folks already on this thread so ask away.

Btw.. now is a good time to replace that belt to a Goodyear Gatorback belt. They are cheap.. buy a new one. On a high boost application belt slip is a big concern. The Gatorback is the only belt i've used that resist slippage the best.

 

[Jinks]

^^^^ What Regan said. Even on a low boost, my Napa auto parts belt squealed like a pig entering a bbq pit. Changed up to a Goodyear gator back belt and all is smooth and quiet. No squeal, no issues. But I am a novice to the whole boosted ctsc thing, I am sure you will get a plethora of information here.

 

[jwmelvin]

My 95 is obdII, so does this make a difference. Regardless, a tune seems to be most appropriate and mandatory?

Yes I would get a tune. A few hundred dollars well spent. And read and consider everything Ryu and Ddozier have written. Like Regan said, ask away. Some of us have a bit of experience and others have a lot more. With OBD2, the NSX offers enough data to permit tuning the FIC and yet is primitive enough to that the FIC works well. I think that's primarily because the NSX does not apply fuel trims during open-loop operation, so your fuel maps actually work as intended.

 

[charlee]

Denso (Supra), Deutschewerks, or Aeromotive all make good fuel pumps. I run the Denso "Supra" pump but it's a relative dinosaur by today's standards. It draws a lot of amperage but it's consistently tried and true and bulletproof. I have very very strong hate for the Walbro 255. Not only are there a lot of fake 255s but mine failed less than 1yr. After learning new curse words by having to remove the gas tank for a 2nd time I will never use a Walbro 255 again. FWIW, apparently their newer generation pumps are better.

Managing heat can be approached in stages on the CTSC. I track my car under insane heat loads and the water/meth solution (see my build thread below if interested) has worked amazingly well. It also has a nice side effect of keeping your engine free of carbon deposits. The methanol and H2O steam acts like a cleaning agent. Cooling is not necessary for safety if your F/IC is tuned properly. However, to prevent heat zapping power loss, you need some way to cool the IAT. I would recommend you don't tune for meth. This means do not have your timing tables rely on the methanol octane. This way, if meth runs out or a pump fails or whatever, your F/IC will read high IATs and pull back the timing safely. jwmelvin's solution allows the use of the factory OEM cover. However, if you spray post blower you cannot. I've found spraying post blower is most efficient by using less water/meth and cools more effectively, but you need to be careful about where the spray nozzles are positioned in the charged air. At your high boost levels, having an equal spray of meth/water into each cylinder is even more important. Spraying pre-blower allows for the best mixture but it also heats up the water/meth molocules and there is debate about the meth eating up the supercharger twin screw coatings. If I had your car, and it's a street car, i'd get everything installed. Get it tuned by a talented tuner (worth their weight in gold) and let him know you might decide to spray ONLY water later on. Move forward from there...

You can also run an aftercooler. It is more complex. More expensive and certainly heavier if weight is a concern. In prolonged aggressive driving it will heatsoak and it does rob the car of some boost pressure as well. The way the aftercooler is sandwiched only exposes half of the heat exchanger to be cooled. If it the heat exchanger core fails it will introduce coolant into your combustion chamber. Though it has it's advantages. It's a set it and forget it solution (don't have to constantly fill the methanol/water tank) and for a street car it's a effective solution. You cannot use the OEM engine cover with this solution as well.

Lots of pros and cons when it comes too cooling. There is no one perfect solution on the NSX. Lots of knowledgeable folks already on this thread so ask away.

Btw.. now is a good time to replace that belt to a Goodyear Gatorback belt. They are cheap.. buy a new one. On a high boost application belt slip is a big concern. The Gatorback is the only belt i've used that resist slippage the best.

Whoa, tons of info here. Will cooling be of a concern if I am only driving on the streets and not going to be boosting for a continuous amounts of time?

Also,what is the part # for the gator belt?

 

[goldNSX]

Will cooling be of a concern if I am only driving on the streets and not going to be boosting for a continuous amounts of time?

You will be fine. This is v1.0 of CTSC by the shape of the blower. With high-boost components. Why not starting with low-boost? It's simpler and safer and doesn't need a good tuner like you NEED one while going with hi-boost and AEM.

One question though: did you get the boost-a-pump-module and the CT FPR as well? They are not pictured.

 

[jwmelvin]

I have a boost-a-pump and CT FPR for sale if you want them but I think you are much better off with the RC injectors and FIC. Much better. Going low boost is fine, you just put a larger pulley on the blower. Don't impair your improved fuel setup.

 

[RYU]

You don't need additional cooling on a street car.

Good suggestions from folks here on trying low boost first. I would echo that.

I'm not trying to make your CTSC more complicated than it should be. If you had the stock CTSC fueling it's 100% bolt on. However, you bought the F/IC kit which is an upgrade but now it requires a custom tune to operate properly. I can't emphasize enough the importance of a good tuner.

 

[elijahcole92]

You will be fine. This is v1.0 of CTSC by the shape of the blower. With high-boost components. Why not starting with low-boost? It's simpler and safer and doesn't need a good tuner like you NEED one while going with hi-boost and AEM.

One question though: did you get the boost-a-pump-module and the CT FPR as well? They are not pictured.

He has a hi-boost setup (includes rc550s, fpr, etc), therefore he doesn't need the boost a pump module or the CT ecm trickery device, as they are only used on stock ecu, stock injectors, stock pump low boost kits, as it keeps CARB regulations.

OP, if you already have a Walbro 255 it's not necessary to replace it. The walbro 255 is the most sold, most common aftermarket fuel pump, and though there are some failures (likely because there are so many more out there than other pumps) 99% of the time you'll be fine. (or maybe i'm misreading and you are still on stock pump)

Also i would recommend at least a higher flowering intake filter, or the CT box. Personally i am running Prospeeds CAI, but i wouldn't recommend buying from them...ever.

If you wanted to run meth/water at some point for cooling you could also run dual maps on the FIC and use a on/off switch to trigger the map switch as well as trigger the meth pump. I am doing something very similar on my aem v1 as i don't want to run meth/water all the time (90% street car) but only when i'm tracking the car or doing heavy multiple gear pulls. This way you get the safety of not having to depend upon meth for octane/knock resistance, but can also have a map for meth and gain the benefits of cooler IAT, more timing, more hp

 

[goldNSX]

Yes, I know. But my suggestion was to start with the low-boost Setup and go from there. That's why I asked for the CT ECM and FRP. With them you could easily start with the low-boost setup. You just take over the stock injectors and install a good fuel pump whereas the 'boost a pump'-module from CT is not needed.

Of course you can also start with a low-boost setup while using the AEM but you need a good tuner then. But then it's not far away of the hi-boost setup if want to go this route. Low-boost is just fine for me, so I stay low-boost. To each his own.

 

[RYU]

For the record: I'm quite happy with the 7lb boost on my Autorotor. It's detuned now to 350wHP/250lb-ft but it feels healthy and so far been bulletproof for 5yrs+ of street and track duty. 350wHP is the sweet spot for the NSX chassis IMHO.

Good luck with your CTSC setup [MENTION=11788]charlee[/MENTION]

 

[charlee]

You will be fine. This is v1.0 of CTSC by the shape of the blower. With high-boost components. Why not starting with low-boost? It's simpler and safer and doesn't need a good tuner like you NEED one while going with hi-boost and AEM.

One question though: did you get the boost-a-pump-module and the CT FPR as well? They are not pictured.

In trying to use all the parts that came with this setup, I want to save and minimize having to source other parts. I will be ordering the pump suggested by Chris at SOS. Its Here: https://www.scienceofspeed.com/inde...-high-pressure-fuel-pump-nsx-fitting-kit.html

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For the record: I'm quite happy with the 7lb boost on my Autorotor. It's detuned now to 350wHP/250lb-ft but it feels healthy and so far been bulletproof for 5yrs+ of street and track duty. 350wHP is the sweet spot for the NSX chassis IMHO.

Good luck with your CTSC setup [MENTION=11788]charlee[/MENTION]

Thanks. I would normally go with the standard levels that originally came with the CTSC kit, but given all the components included, I am getting greedy and want to use all of it.

 

[jwmelvin]

I'm quite happy with the 7lb boost on my Autorotor. It's detuned now to 350wHP/250lb-ft ...

Did you detune by using a less aggressive timing map or by some other means?

 

[charlee]

These values came from SOS

Whipple-based pulleys available:
•86mm (Comptech "high boost")
1. 3.0L NSX: approximately 9 psi
2. 3.2L NSX: approximately 8 psi

Autorotor-based pulley available:
•91mm (Comptech "high boost")
1. 3.0L NSX: approximately 9 psi
2. 3.2L NSX: approximately 8 psi

•86mm (Comptech "higher boost")
1. 3.0L NSX: approximately 9.5 psi
2. 3.2L NSX: approximately 9 ps

What is the stock pulley size that came with the original kit?

 

[RYU]

In trying to use all the parts that came with this setup, I want to save and minimize having to source other parts. I will be ordering the pump suggested by Chris at SOS. Its Here: https://www.scienceofspeed.com/inde...-high-pressure-fuel-pump-nsx-fitting-kit.html

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Thanks. I would normally go with the standard levels that originally came with the CTSC kit, but given all the components included, I am getting greedy and want to use all of it.

I think it's more about pushing your motor that hard (especially without cooling) for little incremental gain. It's just your threshold of comfort.. that's all. Overall the stock CTSC kit is relatively bulletproof but those failsafes are questionable in your setup now due to the introduction of high boost and the F/IC and new injectors.

Did you detune by using a less aggressive timing map or by some other means?

It's mostly "detuned" at near peak RPMs. Most of the powerband is still conservatively optimized for all the parts in the middle to run off horrible 91 CA winter blend gas. How? About .5 points on the AFR towards the rich. The last 500rpm before redline for example, I flood the engine with fuel to reach roughly 10.75 AFR. The timing at full boost (8psi) is reduced. I have about 2 degrees of additional timing taken out before the engine starts to knock on 91 octane. I'm curious how it will do on E85 or race gas.. but i'm not motivated enough to push the timing more. Any more timing and it feels like we're doing something weird like stretching the timing belt or something. I also dropped my redline from 8200 to 8000. High flow cats are also installed on the high side of my exhaust setup which reduces some flow with the benefit of quieter/smoother tone for tracks like Laguna Seca. It was wide open upon hitting VTEC before.

On meth with more timing, bypassed/open exhaust, etc... I'm about 380wHP on a conservative Superflow dyno on the summer blend 91. I'll probably hit 380wHP on a Dynapack with my conservative tune as it sits now. Dynos can be finicky. The car feels amazing though!!! Throttle response and all the important stuff for a driver's car are all dialed in (for now LOL)

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[MENTION=28830]jwmelvin[/MENTION] - i'm still learning this but there's a lot of nuances in the tune that can maximize, say.. for example, throttle response in mid-turn. It's been a whole new learning experience for me and thank goodness my "tuner" is a good friend who will take time to explain the concepts. Right now i'm trying to learn how to introduce those cool pops and gargles upon upshift like on the new cars. It's been a futile effort though. Difficult w/o full control of the throttle body and other stuff. Maybe DDozier know how they accomplish that. It's so cool sounding :biggrin:

 

[charlee]

Yes I would get a tune. A few hundred dollars well spent. And read and consider everything Ryu and Ddozier have written. Like Regan said, ask away. Some of us have a bit of experience and others have a lot more. With OBD2, the NSX offers enough data to permit tuning the FIC and yet is primitive enough to that the FIC works well. I think that's primarily because the NSX does not apply fuel trims during open-loop operation, so your fuel maps actually work as intended.

This is great information and good to know. So in a way is fail safe.

 

[Jinks]

This is great information and good to know. So in a way is fail safe.

To add a bit here Charlee, it may be a good idea to go low boost first. Reason why is because you get used to the power. For the first few months your like, oh hell yeah! Then it grows on you and your looking to upgrade to another 50 ponies.
Just some food for thought. But either way you choose, you already chose wisely. The ctsc is a foolproof way of adding a significant amount of performance for the novice or even the full blown track racer. I love ct products and hope they make a big comeback to bring back the glory days of Acura performance.

 

[charlee]

He has a hi-boost setup (includes rc550s, fpr, etc), therefore he doesn't need the boost a pump module or the CT ecm trickery device, as they are only used on stock ecu, stock injectors, stock pump low boost kits, as it keeps CARB regulations.

OP, if you already have a Walbro 255 it's not necessary to replace it. The walbro 255 is the most sold, most common aftermarket fuel pump, and though there are some failures (likely because there are so many more out there than other pumps) 99% of the time you'll be fine. (or maybe i'm misreading and you are still on stock pump)

Also i would recommend at least a higher flowering intake filter, or the CT box. Personally i am running Prospeeds CAI, but i wouldn't recommend buying from them...ever.

If you wanted to run meth/water at some point for cooling you could also run dual maps on the FIC and use a on/off switch to trigger the map switch as well as trigger the meth pump. I am doing something very similar on my aem v1 as i don't want to run meth/water all the time (90% street car) but only when i'm tracking the car or doing heavy multiple gear pulls. This way you get the safety of not having to depend upon meth for octane/knock resistance, but can also have a map for meth and gain the benefits of cooler IAT, more timing, more hp

Thank you for chiming in. I will be ordering the walbro 255 from SOS. I will never be tracking so hard pulls are far and few in between therfore cooling is not priority.

I wi definately be getting a tune. From looking at my kit, where is the best place to install the fpr?

 

[jwmelvin]

This is great information and good to know. So in a way is fail safe.

I would say that an improved tuning solution is an approach to engine safety but is not necessarily a fail safe. "Fail safe" means that in the event of a failure, a safe condition will be reached.

Many criticize the F/IC because it is a piggyback and cannot control the engine to anywhere close to the same extent as a standalone ECU. It is, however, a big step up in control compared to the fuel-pressure-based tuning of the base CTSC. Control improves both power and safety. Fuel-pressure-based tuning will often run either rich or lean in certain parts of the map, and your only ability to control that is to move the entire map one way or the other. With the F/IC, you can target various parts of the map (the fuel map is the grid of fuel provided for each combination of rpm and engine load) to make sure that the engine is operating with the desired AFR and retard the spark timing to move away from the regime of detonation/knock. Thus, safety is improved by avoiding overly lean AFR (and overly rich AFR that degrades the lubrication film) and by avoiding detonation. Power is improved by optimizing the AFR.

With a standalone controller (or some more sophisticated piggybacks), one has access to many more parameters. Therefore, it becomes possible to actually create a fail safe, where if engine parameters move outside what is deemed acceptable, the system may be put into a type of limp mode or shutdown. I have limited knowledge of standalone ECUs but have done some reading on the Megasquirt.

Some variation of a fail safe is actually possible with the F/IC, by combining it with the appropriate sensor-data system like the Zeitronix ZT-2. The ZT-2 has an output that the F/IC can use to switch maps. Because the ZT-2 can be set up with a number of parameters to control the output, it could trigger a shutdown or limp-mode map if it has access to the right sensors (temperature and pressure come to mind, along with a combination of AFR and load). I do not know of a more convenient AFR logger and data system than the Zeitronix, and have [MENTION=4799]DDozier[/MENTION] to thank for pointing me to it.

I have not implemented the fail-safe system I describe here, as I was using the ZT-2 output to enable my water spray only at higher IAT, although now have moved my water spray to a controller of my own design, which receives all data from the ZT-2 and controls both the pump and a solenoid, so I can use the solenoid duty cycle to limit the water flow rather than just slowing down the pump, and freely control the spray rate. Please pardon the digression. My point is to try and explain what the F/IC is and what it is not, within my understanding (and I welcome any corrections or debates). For me, it is a massive improvement over the base system. I do think that if I didn't have other needs for my money, a standalone ECU would be good. I still need to pass OBD2 emissions, however, so I at least need a functioning system for that (i.e., I would still want the F/IC just to periodically pass emissions with my stock ECU even if I had a standalone).

 

[Fuoss484]

The fuel Pressure regulator was mounted where the latch for the engine glass cover is. It will have an extra long bolt, a plastic spacer, and a mounting plate.

 

[gesundlich]

Want to buy a complete, low mileage Science of Speed Laminova aftercooler kit? No matter how hard or how long i beat on the car, i NEVER saw AIT more than 35 deg F above ambient (on a 3.2 CTSC high boost kit as measured post aftercooler core with AEM AIT sensor). Mine was just removed by SoS in lieu of a twin turbo kit : ) Currently sitting at their shop waiting for a new owner. If you choose to add an aftercooler, this is the time... Before you install the supercharger... As the aftercooler assembly fits between the blower and lower manifold. PM me if interested.

Re: the Walbro GSS342... I've used this same pump in my NSX (switching to the Walbro 450 for flex fuel), two in my GTR, two in my Supra, 4 different STi's and 2 WRX's and never had a single issue with one. Ever. Ymmv, but i wouldn't worry about using one. I HIGHLY recommend hard wiring your fuel pump (SoS makes a nice hard wire kit) if you use ANY aftermarket fuel pump, as all of them draw more current, some much more than others. You'd be amazed as how much resistance the stock wiring offers and can hinder an aftermarket pump's output.