I can rev my fa 20 to 15000 rpm then?

If you de-stroke it to 1.06L and upgrade and rebalance everything sure.

4) RPM: For guys planning serious builds that want more RPM out of the motor the piston style DI pump is a major issue, I shouldn't even have to go into detail about why.

Nice reading comprehension, first of all I clearly stated it's the pump that's the issue. Second the fact that you think a single stroke takes microseconds (that's one millionth of a second btw) tells me just how clueless you are on the topic.

I also clearly stated that many applications benefit greatly from DI, and F1 may be one of them although it took a rule change in F1 for them to switch (and they used to rev higher). Comparing our DI system to that of an F1 car is laughable, we probably couldn't trade our cars in exchange for their DI pump.

I won't bother with the rest of your rebuttals I'm sure any reasonable person can see I already posted the real world relevant test data countering your points that you seem to have ignored completely.

Go do some real world testing and quit regurgitating stuff you read on google you don't know anything about.

This is very interesting OP other than the bickering. I don't fully understand how removing the DI (which I'm sure toyota spent a great deal of money to put in for a reason) is making better power but I'm open to new ideas. I am definitely on board for updates and new information on this. From your dyno charts it looks like you trade power below 4500 for top end power, do you see this smoothing out for those of us with daily drivers?

You have to understand that the OE manufactures put tons of money into fuel economy and emissions not power density which is what we are after. By all performance standards the FA20 is a joke, in the 70's you could buy a 260whp naturally aspirated 2 liter 4 cylinder engine that ran on pump gas. In 45 years manufactures haven't forgotten how to do that, they just cater to the masses. Your average person buys based on mpg. On top of that they have to meet strict emissions standards. That's where the money is spent.

I can't say I know what you mean for "do you see this smoothing out for those of us with daily drivers"

If you mean can it be corrected with tuning or something along those lines than to be perfectly honest no, it definitely can't. The DI system has a definite advantage at low RPM and medium to high load. This could be fixed with a built motor but that's another story all together.

I figured as much, and that was exactly what I meant. I also understand the fuel economy emissions thing. Kinda send like they could have more or less copied Hondas F20 and made the same power without the expense of DI. But I'm no engineer, I just want more power and the cheaper I can get it the better. From what it looks like, in the future I could buy a set of plugs and a tune, maybe some bigger injectors and be able to run much better power if I'm following this all properly... or is this FI only?

Also, what made you guys think... "You know what? This direct inject makes this engine different than all the other subies... let's get rid of it and see what happens..." I'm not hating, I'm just curious. It's a pretty crazy idea. But that's how shit gets done. I'm sure everyone thought the idea of direct inject was pretty ridiculous when that got started too but it seems to be doing well

Honda to be honest is a much better R&D company, Subaru has been behind the ball for a long time (how long can you really have a fuel distribution problem and not fix it). The main advantage Honda has is their VTEC system. It allows a car to get great fuel economy and emissions and then have a radical (over 300 degrees duration) cam profile. It's miles better than variable cam control in terms of performance, the F20c cylinder head is drastically better as well.

Honestly we started the project back when everyone was blowing DI seals and wiping cam lobes left and right. It had nothing to do with wanting to make more or less power, the first few months these cars were out it seemed like it might be a bare necessity for track guys and although we never had a problem with ours (probably because it was tuned the day we bought it) we wanted to make sure we never would and other guys had a viable solution.

At the time I was certain that at worst half a point lower compression would make the DI a moot point. It was obvious Toyota didn't gain anything with it based on the factory power output and to be honest terrible drivability from the factory. I was honestly a little bit surprised that it was actually better without the DI but it does make sense from an engineering standpoint.

As for using it on an NA car, I can't say that we've tried that. My hunch is that you wouldn't gain anything and would probably still lose power down low. I will undoubtedly try it at some point and post up the results but as of right now I couldn't recommend it.

Well I'm looking forward to updates. Please keep us posted

We do still do ECUTek, however we stopped tuning BRZEdit on anything but NA cars. ECUTek is just to much better at this point.

By all means call or stop by anytime. If you want a ride in the shop car you better do it quick before we start on the next project ;)

Serious understatement. Huge amounts of research was/is done to minimize the amount of time and air flow before the TWC reaches light-off temperature and the O2 sensor(s) provides useful feedback. The bulk of preventable emissions happen during that early part of the driving cycle.

OEMs are really creative at dealing with this... with injection methods, stratified combustion chambers, valve timing, knock-based control, and some really impressive prediction algorithms that emulate the O2 sensor behavior as things warm up. All to meet the Tier 2 (etc) targets.

There's still plenty of value in these complex systems, but Carolina Dyno seems to be focused on supporting reliable race cars with high power density. To make high-power DI reliable, you're diving into the deep end of combustion chamber modelling (which is a dark art even with the right software). Couple that with the early issues we had with the DI system, and I'd be hitting the eject button too.

Keep up the good work OP, and know that the silent masses enjoy your posts.

And for the sake of the forum:
60 secs/min * 2 rotations/cycle / 10,000 rotations/min = 12 ms

You generally don't want to run injectors over 80% duty cycle, so the open time will be between 0 and 10 ms. You also have to consider the 0.5 - 1.5 ms latency of injector opening for most systems.

Don't forget that's milliseconds. 12ms = 12000us (microseconds).

You're exactly right about the startup emissions. Combustion modeling for DI has a long way to come and even if the software was there, small shops like ours would never have access. I haven't had that luxury since school. To be honest though the oems put to much faith in models and not enough in testing.

Any progress on this?

The DI delete or the shop car? Nothing new on the delete but we've posted a bunch of shop car updates lately.

Probably why the power hasn't climbed for an engine like this :)

Don't let negative comments get you down. Just do what you do and ignore the rest. Smart people will come to you, idiots won't

The perfirmance of the DI delete. And observations you have made on the deletion as compared to keeping it?

Honestly we probably won't have any further updates because we won't have anything to compare to. We will never have DI back on our car so until a customer chooses to do a before/after test when they install it on their car the results I've already provided are likely to be all there is.

We will continue to run without DI as long as we have the car so we will put testing and miles on it but won't have any kind of side by side comparison of what it would do with DI in the same conditions.

From what I've seen and tested I just can't see any reason to run it. No one has shown anything remotely impressive as far as power/liter that tells me there is any advantage and all of our personal testing showed it was a net loss. That's all the reason I need to take that headache out of a race car.

I would be interested to see the results of no DI. Running just the ports would certainly simplify a standalone ecu choice.

If you want to test a set and provide your results including logs & dyno or trap speed results I'll send you a free set. I've seen you post on various forums and know you would provide a proper analysis if you were interested.

I am going DI delete on my engine, which will have Carillo rods, custom CP pistons and a dry sump strapped to it.


The combustion chambers are being welded up and reshaped. We just need to decide what to do around the squish area and what design to go with for piston crown?


I'm looking for a little advice if there's any out there?? I look forward to my PM box being filled by Carolina Dyno??

What is your power goal? Naturally aspirated or FI? What kind of racing will you do with it?

Ditching the DI puts you back into a world that has been fully developed. CP knows what a piston needs to look like for any PI application and any decent cylinder head shop should know what to do with the heads. You're not reinventing the wheel so the answer should be pretty cut and dry based on your intended use of the motor.

Hi, I will be going for something around the 500 whp level. I will be going to CP pistons and am having the head work done by Race Developments here in the UK. He knows exactly what to do and has been reshaping CC's all his working life?


I really look forward to the results..

Well, I've made the bungs and had them welded in. The inlet seats are now being replaced as they "may" have moved, so better safe than sorry.


Pistons are on order from CP without that horrible triangular hollow and no sharp edges.


Re-profiling of the combustion chambers is next on the list then we're done. I think I may be the first to do this eh??

I'm all for new ideas and stuff but wouldn't it have been easier and cheaper to just swap an EJ25? I'd very much like to see before and after power numbers if possible

One of my DI's crapped out on me the other night when we were tuning. This is when we started thinking about deleting it as well. I'm not a tuner and don't have much knowledge or experience in tuning. But with the help of Steve Kan at PRT Performance, we built my motor.

After clogging or blowing one of my DI's we started thinking about this. Just don't really know how it would affect the engine and the performance. Steve suggested that we set the overlap to 100 (don't even know what that means). I would love to hear more about this from you @Carolina_Dyno

In the mean time, I'm going to replace all 4 DI's just so i can have her back up and running. Haven't felt the power of my car in a long time. Steve thinks maybe the paper element from the fuel filter might have clogged it up. We did an ohm test on the bad injector and a new injector and they both read the same. We powered up the old injector and it was pulsing and a bit of fuel came out too. We were kind of stumped on what happened, but we went ahead and replaced it with the new one anyways. Steve feels the car still doesn't feel the same, so I'm replacing the other 3 today. But again, would love to speak to you more about how you're deleting the DI's!!

Just FYI on my build:
11.5:1 CP Pistons
Carrillo Rods
FBM Stage 2 head with Stage 1 cams
FBM Turbo Kit (Modified)
custom intercooler and routing
3" DP and straight pipes
ID1300
PTE5858
Aeromotive FPR
E85 lines and fittings
Integrated Engineering Surge tank with a Bosch 044 pump inside
Walbro 485 pump in the oem hanger
Return fuel system
Running strictly E85
*Installing a fuel lab 75 micron fuel filter after the surge tank today*

We put out 522 whp on a dyno dynamics on the stock motor and 452 on our mustang dyno

We're still finishing up the tune after we get the new DI's in this wknd. We did 404whp on 17psi on the mustang dyno before the DI crapped out

ok just read thru the thread (even all the bickering) guess i won't be deleting it anytime soon.. don't feel like rebuilding this motor again LOL but I definitely would love to hear more regardless! and about other things yall are working on :)

Everyone swaps the engine out for something or other. I want to build my FA20 to see what it can do. You should congratulate me for having the balls, ( or stupidity)? to do this!!

So, if we're gonna do this, we best do it right. Make it like there were never any holes for DI in the first place and also get pistons made by CP without the DI recess.


First things first, plugging the holes..
http://i494.photobucket.com/albums/r...te%20bungs.jpg
I turned up these to press into the head and sit at the bottom of the chamfer so they look cool. The long thin shaft is a nice snug fit in the injector bore.


From the outside..


http://i494.photobucket.com/albums/r...s%20fitted.jpg


Here we are from inside..


http://i494.photobucket.com/albums/r...fitted%201.jpg


Welded up, polished back and new seats fitted and cut. The heads have also been skimmed.


http://i494.photobucket.com/albums/r...20complete.jpg


All this work is done by Race Developments in Gloucester. Tim really knows what he's doing with all this stuff!!

Holy Legit!

And here is the finished article ready for you to collect. A shame we didn't weld the ports up but hey ho.
The new non-DI pistons might be with me before Christmas with luck :thumbsup:

Fancy welding the ports then Tim?? I know how you LOVE welding Ali!!

Awesome work @Nigelr32

I hate it. Literally. Aside from drinking beer it's the least profitable thing I do and thing that makes me sweat the most hahahaha

The new custom CP pistons are nearly here. as soon as I have them, we can all see what they look like.

And here they are!!


CP Pistons, one off design by Race Developments Gloucester


http://i494.photobucket.com/albums/r...%20Pistons.jpg

Beauties, what the compression ratio on those?

With the head mods, 9.5:1

are those the thick CP pins I can't tell in the bag but if they are not I would consider the thicker pins.
You have way to much work in this to risk a pin failure or piston cracking from a thin pin.
Sweet build anxiously awaiting results.......

They sure are uprated. Stock FA20 CP pin vs our uprated ones.

i have the upgraded JE pins. big difference between them and the ones they came with. worthwhile upgrade