Tested: PRL Motorsports CivicX RACE Downpipe

Well, after not getting any results worth talking about using my high octane fuel PRL has dubbed as my “secret sauce”, it was time to go back to low octane fuel and see what this downpipe could do — if anything. As much fun as it is to just push the motor and turbo to it’s full potential using the best stuff you can throw at it — testing on the average every day fuel most people will use is more realistic. And well — nothing gets more real than running this car on 87 octane, probably the lowest octane you can get in the USA (I’ve seen a few remote locations with 85 or 86 octane, but that’s really rare).

The results were pleasing.


I feel that I have to explain a little bit of the innards of the ECU here, so some of the results will make sense. For anyone installing the PRL downpipe and expecting some results with either the factory tune or one of the basemaps with their tuner of choice, you need to understand where some of the “gains” are coming from.

The CivicX ECU doesn’t use a standard turbo wastegate for boost control — it uses an electronic wastegate run by the ECU. This is more complex and actually very cool. Most “standard” boost control systems use a boost solenoid (mac valve or similar) and when you ask for, say, 20psi, it tries to target that immediately and let the turbo wind up as fast as it can.

This is not the case with the CivicX. Honda uses a “slope” or “ramp” style boost control. Essentially it knows “X” wastegate position means “Y” boost and will actually “ramp” or “spool” the turbo at a fixed rate to get there. This induces artificial turbo lag. I believe this is done in part to protect the CVT trans and possibly to protect the motor — as this little turbo has the potential to “wind up” (spool) VERY quickly if it’s unleashed.

So why is this distinction important? Advertising that anything will make “peak torque sooner” is actually not quite true. In repeatable and consistent tests peak torque is always the same spot as that is where the ECU finally lets the turbo reach it’s target boost. If we didn’t have this control in the ECU I can imagine peak torque being 2200-2500 rpm on this motor with this downpipe.

However, since the ECU is programmed for a STOCK downpipe, when you install an aftermarket downpipe (PRL’s in this case), the exhaust flows more freely and as a result the turbo will TRY to make more boost than the ECU wants and at potentially a little different “ramp” as the wastegate control in the ECU isn’t compensated for this new part.

So what did I find? When I tuned the car stock on 87 octane bone stock, I targetted 18.4psi and the boost level stayed very close to target boost. To try and give us 1:1 results at the same boost level, I actually had to target 17.5psi to get the same boost level I had before installing the downpipe. You can see this in the side by side comparison in the image to the left. I forgot to get this dyno comparison off the dyno computer before I left the shop, but keeping boost the same we saw 8-9whp on the top end and 10-20wtq gained. Keep in mind this is over our “stock tuned” 87 octane test — so we’d already worked on the timing map and fueling a bit as well. You’ll also note as we put load on the car before starting the pull — the turbo was already making almost 2psi more than before the downpipe — this will come into play later.

What does this mean to YOU? If you’re running the same tune with a freer flowing downpipe you will artificially increase the boost level a bit. This will have gains on lower octane fuel as you’re not at peak turbo performance on the stock downpipe on lower octane fuels. Just understand where those gains are coming from — it’s not all just the “tune” at this point. The ECU *will* try to normalize the boost control and bring it back down to the target as the pull goes on (as you can see it happening).

The Install

The PRL items, as always, are quality pieces. Very well done items and fitment on our car was like a glove. No rattles, no rubbing. If you don’t have a lift the install will be a bit more entertaining. On my lift it took about 2 hours to get the stock items off and this one installed. The studs in the turbo can be interesting — PRL broke theirs. I managed to get mine off without any breakage or stripping with the use of some magic lube.

Some pics, of course.

So What About The Toon?

Note: blue is HP, yellow is TORQUE, orange is BOOST.

So let’s try to give it a bit more boost and see what happens? Increased the boost level about 1psi (don’t want to go crazy with 87 octane) after adjusting the timing map and such — and the results were nice. 20whp and 30-32wtq gained.

Torque came in sooner too, right? Of course — if we didn’t have the “ramp” based boost control it would of come in even sooner, but we got maybe a 200-300 rpm improvement because the turbo just wants to GOOOO with the free flowing downpipe, even if the ecu doesn’t want to let it! Peak torque however — was still the same spot. This should never really change as long as the load & ramp rate of the pull is consistent (not all dynos can control this — and certainly load will vary on the street).

But hey, let’s try to give it a little bit more. In the dashed line we increased boost a bit more (with a few other changes), and as you can see the gains were marginal — a bit more torque, but top end HP actually suffered a bit. We’re now at the limits of the fuel and I was starting to see the knock limit approaching very rapidly — don’t want to run here long term at all for reliability’s sake. But hey, overall we still saw 5-8wtq more which amounted to 35-40wtq through the mid range and we still picked up 20wtq up top.

So if you want to run on readily available fuels and not go hunting for race gas or some sort of “secret sauce” (lol), then PRL has a great RACE downpipe. Expect to see diminishing returns in how much HP you can make with better fuel — on 93 expect maybe 8-10whp more with this downpipe. Of course more torque as well — if your clutch can take it.

Vs Bone Stone?

Don’t really need an explanation I think?

87 octane fuel.





Where can you get all these goodies? Right here, along with tunings and custom tuning!


What About Dat Short Ram Intake Doe?

Back to Honda today…

If there is one question on the interwebs that bugs the crap out of me, it’s definitely “What intake should I buy?”. Really? Come on! In this day and age Google knows that answer. So I’m not going to talk about what intake you SHOULD buy, but what intake you SHOULD NOT buy.

Short Ram Intakes Suck

Now I do realize this is a bit of a generalization as there are some exceptions (namely SRI’s designed to point at fresh air and are directed completely away from any heat sources).

Generally the SRI style intakes commonly found on the 8th and 9th gen platforms all point the filter/inlet at the back of the engine bay. This is just plain dumb. Some people will argue that the intakes do “make power” and the manufacturers claim absurd (and unrealistic) “gains” from this style of intake.

The actual FACT is these style of intakes breath hot air from the back of the engine bay — fresh air rarely, if ever, makes it to the intake and it’s pulling very hot air from an area of the engine bay where the exhaust manifold is emanating a generous amount of heat. Hot air does not make power — in fact it creates a scenario that is unsafe for optimal engine operation and you have to “dial the tune back”, something I’ll address in a bit.

The Snorkel Mod

This is a fun mod — I’ve seen this a lot and some places claim to do this to try and create “conditions similar to the street when the car is moving”. So at the heart of it they know these intakes breath hot air. This is just a cop out to “make numbers” — gotta get a print out to race the dyno sheet online, right? I don’t care about “numbers”, if my dyno generated absolutely no numbers and just a power curve I could still do my job. We sell tunes, not numbers. Let that sink in.

So what do they do? They point the IMG_0953intake out of the engine bay to artificially reduce intake air temps (“IATs”). Sorry to break it for you — this doesn’t mimic actual road driving even remotely. I actually see IATs dramatically increase in “normal” driving conditions — as high as 40-60 degrees over ambient with these style intakes.

So let’s use the tool at our disposal — the dyno — to get empirical data on how the engine is affected by changing the position of this style SRI.

The Test

vs_stockThe car in question is a 2013 Civic Si w/ said SRI, catted Full Race DP, RBC swap and stock exhaust. The change over a completely stock car looks like so. Overall not a bad gain, and as always, the RBC sacrifices mid range over the stock intake manifold.

Now that we have done the “tuning” to extract power, let’s see how intake vs_in_engineplacement affects power. We turn the SRI back into the engine — but leave the hood open, and do a subsequent pull (making sure engine conditions are at steady state — meaning we don’t have a heat soaked car with a high ECT, we make sure we start at the same temps as a high ECT will cost power as well and render our test meaningless). The chart to the left demonstrates this change — all we did was lay the intake back in the engine bay — and we lost on average 10-12whp and 10-14wtq! Really?? What???? WHY IS THIS??

shut_hoodBut it gets better, what happens we if shut the hood? Whoops — looks like we lost another 5-8whp and 5-6wtq just full_vs_shuthoodshutting the hood over our previous pull. The left chart demonstrates how much we lost overall — as much as 20whp! No way, right? Yes way!

Why Does This Happen?

This is actually quite simple — when you tune a car, particularly on the dyno, you are tuning in as close to steady state conditions as possible. You do this so when you make changes in the ECU (“Tune”) you can verify your changes have some sort of impact on the way the motor runs. Whether this is good or bad. You also have to make conscious decisions on how you want to leave the motor running long term — these should be intelligent decisions as they will dictateiat not only long term reliability but how well the motor runs in dynamic conditions which the ECU does have to account for.

So why the power loss? Quite simply, Intake Air Temps went up and the motor got warmer air as conditions changed. The read outs to the right indicate what the intake air temp (IAT) was on each pull. As the IAT went up, we had a respective drop in power. Will this drop in power continue to get worse as IAT climbs further? Absolutely.

In fact, as IAT climbs, the motor will run hotter and less “stable” (to put it in simple terms), which will create situations in which the motor can “knock” or “detonate” — which is an unsafe condition where your combustion event is no longer in a safe and controlled burn and will destroy your motor if left running in this state. The ECU allows us to account for this timing_reductionbehavior — by reducing time and/or adding fuel. An example of this is in the table to the left. Does reducing timing hurt power? Absolutely. Is it necessary? When the motor could potentially see unsafe running conditions — absolutely. You want to protect the motor as much as you want to make power.

Tuning Tool

Now back to those dyno “numbers”. A dyno, any dyno, is a tool. You can take your car to 15 dynos and get 15 completely different “numbers”. You can always “make more power” when you stick a car on the dyno and make changes in steady state conditions — especially if you disable any of the dynamic compensations the ECU will apply to protect the motor. Factor in strap down variances (particularly on roller style dynos) and your numbers will potentially be all over the place from day to day, dyno to dyno, etc.

I use the dyno as the tool it was meant to be. Making power is awesome — fun even, but at the root of it, the correct PARTS will make power, and will potentially make better power in fluid day to day conditions as well. The tools at my disafr.pnposal will let me find where the motor runs best, runs safest, and how it responds to the changes I make.  Tests like finding out what AFR the motor runs best at — and what AFR it actually starts to lose power (from either running too hot, or “choking” on the fuel). Yes the plot to the right is an N/A 9th gen, the AFR it loves to run at might surprise you — it definitely isn’t 13.88.

In Conclusion

It’s easy to hit the plus key on your keyboard and keep on pumping timing into the motor to “make power”. It’s all fun and gains til it melts a piston or throws a rod and the oil pump “failing” gets blamed for the motor going out. We’ll be having none of that here — a lot more to tuning than “making power”, sorry.


I’m The Best Tooner In The World!

Because I made X amount of power or I made Y amount more power than Joe Bob Smith!

Now that I have your attention, it’s time to get serious.

This blog has been a bit quiet since I’ve been busying moving into the new shop, getting the new 4WD dyno setup operational and all that MoTeC development (more on that another day… you guys following our FB, YouTube & Instagram have probably seen some of it)!

What I wanted to discuss and address today is a small scope of what “tuning” is and what role “making power” plays into it — with some practical examples.

What is Tuning?

A lot of people bring their car in or buy a tune and want to make more power. I have to break it to you — this is the lowest form of tuning. A trained monkey can run a car on a dyno, smash on their laptop and make the dyno graph go up. None of this is any indication the actual calibration (“tune”) was done properly or any intelligent decisions were made.

That’s the biggest part of it — using the dyno (or datalogs, or street, however you’re doing the tune) as a TOOL to make intelligent decisions about how you are going to leave a motor running long term.

Today’s example is brought to you buy a 2013 Civic Si w/ just a Takeda intake. The vehicle runs quiet enough that you can very easily distinguish any scary situations (knock especially) and isn’t so radical that pushing the motor a bit too much will cause damage from a few test pulls (the Honda community has long been spoiled by very strong motors that take abuse for a long time before going BOOM).

Making Power

Something I’ve iterated to people over and over — parts make power. The tune wraps it all up and an intelligent tune will leave the car running SAFE and reliable for a long time. Can a tune make power? You bet. Will a tune make power? Sure. Will the tune make power SAFELY? Um…

I love having our Dynapack at my disposal — I can make minute changes in the tune and see the difference. So let’s take a look at a practical example of making power safely.

All the fueling and VTC were already tuned up to this point and we’re in the “sweet spot” here. On this initial graph we also found a power curve (for the sake of a concise discussion we’re just sticking to the top end of the power curve) t1_morehat’s what we can call “clean” — dyno says the curve is clean, ECU is reporting no knock, and your senses are telling you all is OK. This is the solid curve in the next two graphs and we’ll call it our “baseline“. So let’s try a minuscule change — 1 degree more ignition timing. Hm.. looks like we found 2-3 more hp (dashed curves). But wait… it also knocked on this pull, not only via the knock detection in the ECU — but your ears hear it too. But it’s making power — sure not a lot, but it’s making power!1_less

Well, let’s go the other direction — let’s try 1 degree less. Interesting — now we’re making 2-3 hp less (as much as 4hp less) than our “baseline”.  So if we factor in the “gains” we saw in the previous test, that means we’re now down about 5-6hp on “max power”. Hm… how about we go back to our “baseline” and 1_less_finalgive it a short cooldown (as the engine got a little heat soaked during tuning — this is normal and expected during a session). We’ll compare this pull to our “1 degree less than baseline” pull which arguably for most people is “safe” (more on that later…). and what do we see now? Well crap, we’re down like 6-8hp in some areas. This is a lot of power N/A, especially for a car with just an intake!!! Right? RIGHT?


Decisions. Decisions. Decisions.

This is were some intelligence and decision making comes in. Effectively what we’ve found with just those three pulls is the knock limit, actual audible knock and a spot just under the knock limit. We’ve also proven that you can absolutely make power  while knocking, or at the knock limit, and a small cooldown will make a few more HP.

Keep in mind this is all done in a controlled environment — our conditions have not changed during the session. We’re not seeing varying loads or acceleration rates (someone doing a hard pull getting onto the freeway or down the straight on a road course…). We’re definitely not seeing extreme weather swings (super cold to super hot). What makes “best power” and is “clean” on a dyno today, may be beating the motor up tomorrow… what about if it gets to triple digits outside and the intake is pulling charge temps into the 140*F? Does this change how the motor runs? Does this impact how the tune should “adjust” or “adapt” to these conditions? Absolutely — in fact I have yet to see a single ECU that doesn’t let you build in compensations to ensure the engine runs safe in all conditions. Does this affect the power the motor makes? Absolutely, you can see radical swings in power!

So ask yourself, where SHOULD you leave the motor running? Should you leave it right at the knock limit simply because it didn’t knock in the datalog and your ears didn’t hear any (not every car will be quiet enough for you to hear detonation…). Or is a safe point going to be somewhere that might be what we consider “leaving a lot on the table”?

Hell I only showed the difference two degrees makes… and this may not even be the “safe” spot to leave the car at long term. What if it’s 3-4 degrees of timing under absolutely max power? How much are we “leaving on the table”? Is this necessary to ensure the motor is safe for what the owner of the car is going to be doing?

My job as a reputable tuner is to leave the car running safe for years to come — in all the elements and any conditions. So I know what I would do, and I know exactly why I do what I do.

The Dyno Phenomena

This brings up an interesting point — people get blinded so much by peak power figures on a dyno sheet that they forget what tuning is for. A dyno is a tool and not there so you can race your dyno sheet — it’s a tool to get a job done. You can always “make more power” when loading a car on the dyno, any dyno. Only an incompetent tuner will leave a car running on the knock limit. But hey, if they do — a little while later it was just “bad fuel” that got you, right?

There’s a difference between a proper and correct tune — and “making power”. You’re not uncovering Egypt’s secrets by “making power”. So sad, right?

Bro You’re Running Rich!

I love this topic — it’s probably one of the most common online aside from people racing their dyno sheets online and arguing about “bro that’s low you should be making X power”. LOL.

Yes, LOL.

Although there IS a point where it’s too rich — all motors have a “sweet spot” they like to run in as far as fueling under full load (dependingfueling on fuel). Here’s an example that shows the motor run at 12.2 AFR, 12.8 AFR and 13.5 AFR (roughly). Note the torque curves on the left… almost identical. Fuel curves on the right graph. The timing map remained the same on all 3 pulls, as did VTC. Only variable changed was fueling used. On the orange plot (13.5 afr) we had some light ping — which again did not affect power output.

So what fueling would you run?

The Tooner Phenomena

Now I am sure this is going to ruffle some feathers and some might even dust off their pitchforks — so be it. It has to be said — living and breathing cars, modifications and tunes day in and day out you see some outrageous things come your way. I am going to break it down into two simple categories — food for thought and enthusiast beware.

The Expert Tooner

This is the guy that has a shop or works for a shop — they have a dyno and you would think they would know how to use it. In fact, some of them do know how to use it very well, and the break down begins with the fact they understand very little, if nothing at all, about EFI tuning and/or the engine management software they are using. Hell, they might even be working at a shop that has a stellar reputation!

They are able to post up amazing numbers on said dyno, but the vehicle will just run terrible either the moment it leaves, or a couple days later. When the car comes back to them — they cannot figure out the source of the problem and will at times chase mechanical gremlins that do not exist.

One prime example of this is a customer with a 2012-2015 Civic Si — said customer had some work done at his location and the vehicle posted up absurd power figures on pump gas (93 octane) — nearly 500hp. Anyone who has any experience with that platform will raise an eyebrow — maybe it’s possible? Highly unlikely with how knock prone those motors are. But hey, the customer was initially quite happy with the numbers — and then the bad news. After a couple of days the car would be completely gutless, and any attempts to have that behavior remedied kept failing.

He finally got a hold of me and we went over what was going on — turns out he was an existing customer of mine that had a tune for his car whnegative_timingen it just had bolt ons. After reviewing his turbo datalogs, it turns out it was running 17-18psi of boost and -2 to -6 degrees of timing (yes, NEGATIVE). It doesn’t take a rocket scientist to figure out this does NOT make power. In fact — it makes about a whopping 200 horsepower with all that boost, not anywhere NEAR the claimed dyno figures.

And yet it continues to get worse — part throttle closed loop feedback was disabled, the primary O2 sensor completely disabled, VTEC point untuned, VTC mapping completely untouched. No excuse for any of these items to be the way they were — so where was the break down? Upon inspection of the actual calibration — the tune file was basically nothing more than the calibration for his vehicle with simple bolt on parts. Quite literally the injector scalar (how big the fuel injector is) was adjusted and the fuel map was roughly skewed upwards in boost — nothing else in the calibration was setup anywhere close to how a turbo calibration should be done to get a reliably running vehicle. You read that right — he was running MY N/A tune on his car with a turbo. You can imagine how well that works.

So how did it make power on the dyno? Quite simply — with every flash of the ECU its “learned” parameters were reset and under boost the motor was seeing effectively naturally aspirated ignition timing. Wait, won’t this cause detonation? Absolutely — this platform does not have active knock feedback logic, only having a very slowly learned correction (which works poorly on modified vehicles to begin with) and the motor will definitely make power.

So the sum of his “expert” tune was nothing more than a couple of hits on the dyno with a calibration that was ripped (stolen) off the FlashPro when the vehicle came in for work to be done.

But a couple days later — the ECU goes limp mode to protect the engine. In this case — the owner of the vehicle was very lucky. We dialed the boost back to 11-12psi and tuned the car properly and it hasn’t had a problem ever since.

The Noob Tooner

You know who I am talking about here — they are all over social media and online forums. They will make you promises and whisper sweet nothings via private messaging systems to get your attention and make your wallet a little bit lighter. I have seen examples of them even claiming:

  • Tune just like “so-so” (enter tuner name here) for the same amount of $$$.
  • It’ll be just as good or better than “so-so”.
  • “So-so” is terrible and they’re better.

What skills, experience and accomplishments do they actually have? Well it’s quite simple:

  • They purchased a laptop.
  • Downloaded some free software.
  • And in many cases: stole a base file they are now using as their “source of truth”.

Yup — that’s right: all it takes to claim to be a tuner extraordinaire on the internet is a laptop and the ability to transform drivel that would normally flow through their lips into text via their fingers rapidly clacking away at their laptop keyboard.

Even better — in many cases they’ve even purchased a tune for their own vehicle from an established tuner. This has happened so many times I have lost count — I am more than happy to share examples with the reader privately.

But you bet they will be all over the internet trying to snag their next victim — sometimes advertising their services, sometimes trying to stay under the radar and snag their victims via the amazing stories they like to tell via private message.

And at the end of the day — they have little to no experience (you will see stuff like “I tuned my car”, “I tuned all my friends”) and no accomplishments of any kind. Of course they will claim that they “have to start somewhere”. Anyone sign their vehicle up as R&D when they paid for a tuning service?

Amazingly enough — they will always have someone “vouch” for them and their “skills”.

So What?

This is a vicious cycle — I’ve seen it so much that I just shrug and let our business and our work speak for itself.

But be warned — the tooners of the world will throw timeslips, dyno sheets and vouches at you all day long and in their minds it gives them completely credibility. Sure — going fast and big numbers are fun, but it paints a very poor picture of any experience or ability to tune a car properly to do anything beyond that. When you have a vehicle you need to drive day in and day out, there is a lot more that goes into setting up a tune than dyno numbers and time slips.

The goal is to hopefully share some insight with the reader and maybe prevent another case of Tooner Attacks. Ultimately it is up to every enthusiast to do their own research — and I encourage you all to do so.

Tested: 2006 – 2011 Honda Civic Si Hybrid Racing Cold Air Intake

Years after the release of this intake I finally had the chance to do a true before and after impartial test of this intake. One of the biggest hyped intakes on this platform — and it really does work.

Now this is a TRUE test of this intake, not your “average test” where they slap on the intake and tune the car and everything that changed was “gains” from the intake. No… just no. All the big intakes require custom tuning or in many cases the car just won’t even run. To combat this inability to “baseline” the car after the intake was put on, many will skip an important step and just slap the intake on and tune the car — not a valid test in any sense.

The simple, yet more involved process:

  1. Baseline the car as it comes in.
  2. Completely tune the car (not this 4k rpm+ rip it and ship it trash for peak #’s).
  3. Install the intake.
  4. Completely tune the car with the intake.

We’re looking at more than just peak numbers, we want to see the whole curve to observe gains and loses throughout the power curve. Between step’s 2 and 4 we now have a valid comparison for the power the intake was responsible for.

So, today our victim was Randy. He purchased the Hybrid CAI from me and turns out his car was a completely stock 2011 Civic Si. Perfect!

I baselined the car completely stock, then plugged in the Hondata FlashPro and stock_vs_stocktuneddid a full tune on the stock car. The results are as follows. Dashed plot is completely stock, solid plot is after the vehicle was tuned. As you can see, pretty good gains across the board just from tuning a stock vehicle — if the vehicle isn’t tuned prior to parts testing, these gains would of been lumped in with the part, which is simply not accurate.

Max got the stock intake torn out and the Hybrid CAI installed. Istocktuned_vs_intaketuned went back in the car and on the laptop for more tuning. Here are the gains the Hybrid CAI facilitated (with more tuning of course) over our previously TUNED vehicle.  Aside from the small loss between 2500 and 3000 rpm, the Hybrid CAI is a stellar performer across the rest of the power curve, with gains as low as 1700 rpm.

So there we have it, unequivocal proof the Hybrid CAI makes power. What were the overall gains from tuning and the intake over a stock car?


Deatschwerks DV2 1500cc Injector Review

Deatschwerks announced their DV2 line of injectors — 1200cc and 1500cc variants — not too long ago. I was fortunate to be one of the first to get the word about these injectors from DW and I was excited to get my hands on both sets to do some testing on my shop vehicle.

Foremost, I want to talk about the 1500cc variant — I’ll touch on the 1200cc set briefly later.

The test vehicle is a 2001 Honda S2000 powered by the F20C on an AEM Infinity stand alone. The fuel system is very simple — the OEM Honda fuel return system with completely stock fuel lines, with a Walbro 485 fuel pump in tank, an AEM FPR and AEM fuel rail sitting over the Deatschwerks DV2 1500cc injectors.

My goal? To make over 600whp (on a dyno that baselined 195whp for the car bone stock) with a Comp CT4x-5862 turbocharger.newmotor_20psi_pump_vs_24psi_e85

Mission? Accomplished. On E85 the vehicle put down over 600whp at 24psi and 525whp on 20psi running 92 octane pump gas.


That is fantastic power for a very simple setup — it’s a 2.0L bottom end with a 58mm turbo and only “drop in” fuel system upgrades (no plumbing new lines, etc).  The only fault in the fuel system is the high fuel pressure at idle — I’ll touch on that later — and the injectors have performed amazing nevertheless.

I am able to run a very wide range of power without swapping parts — no injector swaps, etc. The injectors DW supplied me have been more than plenty for my goal, with room to push to 700hp with a higher base pressure and a different pump/fuel line setup (the Walbro 485 doesn’t do so hot at high base pressures).

Unlike the 2200cc injectors we have been stuck with in the past if you wanted to do a 600whp+ flex fuel vehicle, the 1500’s don’t have the drivability nuances we’ve become so accustomed to — no insanely unstable idle due to the pops and misfires, no weird shuffling at light loads or on deceleration. Even on pump gas — where it is virtually impossible to get a set of 2200cc injectors to behave without running the vehicle at a super rich target lambda.

On E85 the 1500’s have a very slight pop at idle . On pump gas — they are a little “poppy”, but not so much that it deters from the idle or attracts unwanted attention to the car stop light to stop light. Much more than acceptable — they actually make the car very enjoyable to drive without having to put up with drivability nuances. In fact, whether it be on pump gas or E85 — squeezing the throttle rewards you with a smooth powerband, strong spool and very predictable power delivery without the odd “oops the motor missed” as you touched the throttle.

And if the biggest fault I can find with the 1500’s is that on deceleration in rare situations running pump gas I’d get some shuffle — I can easily blame it on the high fuel pressure at idle & low load. With the Walbro 485 in tank, the fuel volume is so massive the small factory return line can’t keep up when the engine doesn’t demand a lot of fuel — this increases the fuel pressure to over 70psi on this car, resulting in effectively a 1900cc injector in these situations. Yet — I was still able to fix the shuffling with a tuning trick, without going to the same extremes as a 2200cc injector.

Better yet — a fuel return line upgrade will bring the fuel pressure down to actual base pressure and clean up that behavior. This isn’t something I’m wanting to do on the car as I have not found it to be necessary — the drivability is fantastic and I just don’t want to change a thing at this point.

Short comment about the DV2 1200cc injectors: they are perfect. In every aspect. If you’re not looking for 600-700hp they’re a great choice as well. I made 575whp on E85 on the 1200’s squeezing them to 100% duty cycle.

Whatever you’re looking for — both injectors are fantastic and I would definitely recommend.  As with all the products I’ve tested and support, these injectors are on the VitTuned Store.