CR-Z Si - Building the Real Hybrid Hot Hatch

Welcome to the build thread for my 2011 Honda CR-Z 6MT. I acquired this little car a few months ago and have fallen in love with it. This thread will document my mods and journey with this cool little hybrid/hot hatch/CRX revival.

There are some major design pitfalls but lots of hidden potential with this car. From the factory Honda could have done so much more with it, but didn't. This would have been a great base model to a CR-Z Si but on it's own of course it left too much on the table.

My plan is to make it into a proper, true successor to the CRX Si; the CR-Z Si. I have owned several CRXs and Civic hatches so I know the lineage quite well. The CRX and hatches and various submodels brought fuel-saving technology like CVCC, lightweight and basic design philosophy, and a sporty chassis together to create the legendary cars we know and love. The CR-Z does something similar with a small 4-cylinder engine augmented with an electric hybrid motor, snappy transmission, perfect weight balance and great looks. I want to bring out the potential by upgrading the engine and chassis to Si-spec. Not only that but also upgrade the hybrid system with lithium batteries and boost the electric motor output from 10kw (14hp) to 30kw (40hp).

I'm really smitten with this little car. It's one of the best looking Hondas of all time IMO and the handling is just great. I really am shocked at how well it handles out of the box. Of course I could swap a K series or something but that is just so basic. I really am looking forward to the hybrid system modding and building a little screamer of a 1.5L at the same time.

Things I love about the CR-Z:

-The looks

-The MPGs

-The handling

-The snappy 6-speed transmission

-Good brakes

-Comfortable

Things I don't love so much:

-God it's slow

-IMA (hybrid) assist is too weak and doesn't last long enough

-The final drive is too tall. Good for MPG--bad for rowing through the gears

-No LSD

-The doors are freaking heavy and the door stops barely hold them

-Impossible to see out of when trying to change lanes

-So slow

So far I have done some fixes and some mods and I have lots of plans. I will start to document them here. 

First things first I baselined it. I cleaned up the interior and polished the headlights. It's really clean!

It came with a shorty K&N intake and Megan fart-pipe muffler. Both had to go. I hate the noises they make and the looks. I installed a stock airbox and did the "Spoon mod" i.e. removing the internal baffles. Supposedly that allows more flow.

I also installed a slick AEM cat-back exhaust: https://amzn.to/3K3ijzA

Then I adjusted the valves and changed the spark plugs.

Cool project, excited to see where this goes

Yes! I've always wanted to see one of these get built. I'm a fan of the looks as well and looking forward to seeing the process.

These are great looking cars and seem to have a lot of potential. I'm looking forward to watching.

I wanted to get a good performance baseline before I start modding the car so I can see what works and what doesn't. I used my Dragy device, a little GPS gizmo that works with a smartphone to measure 0-60 and 1/4 mile and other performance metrics with extreme accuracy. The Dragy is supposedly as accurate as you can get without actually going to a drag strip: https://amzn.to/34OM9ru

I bought a Flashpro and Zeitronix E85 content sensor kit. I had read that Flashpro allows E85 ethanol input, but it's only on some models. Apparently the CR-Z version does not support it and I didn't learn this until after I bought and installed it  In this case I'll just have to run two maps, one for ethanol and one for gas. Luckily E85 is super plentiful and cheap in my area.

The stock redline is 6500 so I bumped that up to 7200 RPM. You can start to hear the valves float above 7400ish and the power drops considerably after 7k anyway. Also the IMA system throws error codes and drops out for 30 seconds if the engine goes above 7000 RPM for more than a few seconds (no bouncing off the limiter just for fun ). 6500 is just too low and when revving out in first gear you always hit the limiter. Other than that I just tried to clean up the AFR to be 13:1 at WOT and added a couple degrees of timing.

I live in Colorado at 5400ft elevation so times are slow compared to published times FYI.

Baseline runs:

Run 1: stock ECU, stock airbox, AEM exhaust. No other mods or changes. 91-octane fuel shifting at 6500 RPM
Run 2: Flashpro tune, same otherwise. 91-octane fuel shifting at 6500 RPM
Run 3: Flashpro tune, same otherwise. 91-octane fuel shifting at 7200 RPM

Run 1: 0-60 - 12.96 sec, 1/4 mile - 19.04 sec @ 69.38 MPH
Run 2: 0-60 - 12.25 sec, 1/4 mile - 18.60 sec @ 71.59 MPH
Run 3: 0-60 - 11.91 sec, 1/4 mile - 18.56 sec @ 71.9 MPH

Pretty good results for just a ECU tune!

I added a couple little things that I like to add to all of my cars. First is Drop Stop. I dropped my phone down in between the seats and the console on the way home from buying it. It was lost until I got home and had to use a flashlight to find it. Not anymore!

Drop Stop: https://amzn.to/3refL9k

Speedy-fill gas cap. A requirement when running E85 haha!

Gas cap: https://amzn.to/3GrtYGg

My dog loves this car. He fits so happily in the back area.

Or the front keeping guard while I'm at the pull-a-part

The wheels have old pastidip or something on them that I've been trying to get off bit by bit. At least they are in nearly perfect shape! No curb rash or anything. Apparently these are super light 16" wheels, they weigh only 15 or 16lbs I think. It also came with great BFG all-seasons to get me through the winter and brand new brakes all around. The PO insisted!

So all BFGs are getting those Rival-esque shoulder blocks that go into the sidewall? I was sitting in line somewhere and saw some forgettable crossover with tires like that and was like, "Someone put Rivals on that?" But no.

A common mod to these cars is to install the Honda Fit GE8 intake manifold and also camshaft. I didn't figure out about the camshaft until after I had already installed the intake manifold. More on that later...

I wanted to add a little paint to the intake just cuz I could. I was going to do wrinkle red, but everyone does that. So I thought maybe wrinkle blue....but then it dawned on me! It's a hybrid, I should paint it GREEN! Hahaha of course. So I hit it first with some wrinkle grey and then went over the top with Platinum Green. Definitely none other like it!

I also started running E85 fuel and re-tuned the ECU and ran some faster times!
 

Previous best (91 octane, CR-Z intake): 0-60: 11.91 sec, 1/4 mile: 18.56 sec @ 71.9 MPH
New best (E85, GE8 intake): 0-60: 11.04 sec, 1/4 mi: 18.10 sec @ 73.55 MPH

Lastly I installed these awesome CR-Z logo projector door lights. They are sooo cool! Link to buy: https://amzn.to/3fizijk

The prius guys have talked about making adjustments to how the atkins cycle motor runs and hotrodding them.  Not clear if that's applicable here but love where this is headed.  Are they motor swap friendly while retaining the hybrid?  Wondering what the hot hybrd assist would be like one on of the k motors...

The same day I installed the Honda Fit intake manifold I read that the Honda Fit GE8 also has a different camshaft. The CR-Z ZF1 cam only opens 3 valves at low RPM and then all 4 at higher RPMs. The Fit uses all 4 valves on both sides of the cam and also has more lift. Together this is worth 10-15 hp with a tune. It also is the reason for the HP difference between the CR-Z (112) and the Fit (117). This camshaft made a noticible improvement in all around power and torque. It is especially noticible at higher RPM as the motor now freely revs to 7000 RPM very happily. On the highway in 5th or 6th gear the extra torque is very noticible and makes it much easier to cruise without having to downshift for every hill or pass.

Oh well, I am getting good at removing the intake and adjusting the valves at this point 

Pulled the cam and rocker assembly from a 2013 Honda Fit:

Fit on the left, CR-Z on the right.

I dialed in my AFRs and ran some new times. We broke in to the 17s! Yeah baby!!! 

Previous best (E85, GE8 intake, CR-Z cam): 0-60: 11.04 sec, 1/4 mile: 18.10 sec @ 73.5 MPH
New best (E85, GE8 intake, GE8 cam): 0-60: 10.78 sec, 1/4 mi: 17.96 sec @ 74.4 MPH

In reply to 84FSP :

I do not think the IMA hybrid trans is compatible with the K-series but that would be really cool if it was! When I bought this car I was also in posession of a K20Z3 and 6-speed but resisted the urge. I really want to see what I can do with this car. It is a normal cycle engine, not Atkins cycle like the Prius. There is a guy named Peter Perkins who is pioneering the way in the Insight and now CR-Z community of hotrodding the hybrid system. He has boosted an Insight and CR-Z both to 30kw (40hp) assist! About the same torque boost also. That combined with a nice n/a build should make this car a lot more fun! If not there is always a supercharger or turbo kit, both are available.

J1000 said:

Welcome to the build thread for my 2011 Honda CR-Z 6MT. 

 

Things I love about the CR-Z:

-The looks

-The MPGs

-The handling

-The snappy 6-speed transmission

-Good brakes

-Comfortable

Things I don't love so much:

-God it's slow

-IMA (hybrid) assist is too weak and doesn't last long enough

-The final drive is too tall. Good for MPG--bad for rowing through the gears

-No LSD

-The doors are freaking heavy and the door stops barely hold them

-Impossible to see out of when trying to change lanes

-So slow

 

Fix your atmosphere and you will fix most complaints! 

These are not fast cars but your mile high 0-60 is painful. IMO the gearing on these is about perfect, you are just down on power. Compare to fit or insight.

Check out the HPD catalog for a supercharger clutch and LSD! Seems like Honda did make an unofficial si through HPD.

The hatch is super useful, I swapped my crz for an Acura TSX and am frustrated in the utility downgrade.

I'm curious what your plans for hotrodding the ims system are. 

Be gentle with the exterior door handles, they break and new Honda parts are expensive and not improved.

Honda makes a center console/arm rest that mounts where the rear cupholder is. I found it improved comfort 

Interesting you are going after rpm with stock cams, I always felt the engine didn't want to rev (at sea level). 

20kw more assist on that tall geared low torque motor should be a HUGE help. I'm assuming it's mostly made through increasing torque  in first 3000 or so RPM's?

Very cool! Especially excited to see the battery improvements.  Are you in the Denver area?

I was always intrigued by the CR-Z and very nearly purchased one (got to the initial negotiation stage but backed out when they wouldn't budge AT ALL on the dealer addendum). Pretty awesome to see that they can be pretty easily perked up - might make a good runabout beater when I have to start going into the office again...

Loving this. Wife loves crz in general, this might be my excuse to get one. 

So in the meantime before I upgrade the battery I wanted to do a couple charge/discharge cycles on my IMA battery. It is Nimh chemistry which is old tech, but tried and tested. Nimh batteries can be brought back to nearly their full original capacity and power by doing charge cycling on them. The process is to basically use a very small trickle amperage to fully charge the cells, and then use a small discharge current to bring them all the way down to 0v. The process takes several days as you are supposed to charge for 24 hours/discharge 24 hours and then repeat 2-3 times. You can discharge them by using a simple incandesent light bulb. I shortened the process a little bit with two lightbulbs instead of one and still ended up with the computer showing I had 75% usable capacity which is the most the computer will allow.

First things first I got this little gizmo from Peter Perkins called the OBDIIC&C. It plugs in to the OBD port and can show all the battery and IMA system stats like voltage, amperage from battery, motor amp draw, 12v system voltage and draw, battery temperature etc etc. Really cool. It also measures the Usable Capacity and State of Charge (SoC). It also can force the battery SoC to low, medium, or high. In this way you can force the car to think it has a full battery and give maximum assist power for a short period of time (2 minutes or so) or you can force it to think the battery is very low and it will start charging the battery at idle. With these tricks you can slightly overcharge the battery and discharge it further than the car would otherwise allow. At the moment it provides minimal benefit, but with a custom battery it can unlock more performance.

If you want to learn more about the OBDIIC&C check out this thread: https://www.crzforum.com/threads/crz-obdiic-c-obdii-command-control-display.94444/

Here is my OBDIIC&C, you can see on the top row U75 which shows that I have 75% Usable Capacity after my battery charge cycling.

I wired some small wired directly to the battery terminals for trickle charging and future use:

The setup (my wife thinks I'm crazy):

In reply to daytonaer :

Yeah well unfortunately that's what I got  If I go up into the mountains for twisty roads it gets even worse. I grew up driving 1.5L Hondas and 1.6L Miatas so what can I say I'm used to it  Knocking off 2 seconds from my 0-60 is totally worth it!

The HPD stuff is cool but expensive. I'd rather have a turbo than centrifugal blower also. I'm not so much "going for revs" as just gaining a little breathing room. I want to autocross and it's going to be useful there too. 7000RPM is plenty I think.

In reply to MrJoshua :

Yeah that's what I'm looking forward to! The IMA assist actually lasts until 4500-5000 RPM before it starts petering out.

In reply to sobe_death :

Yep in Morrison

In reply to CLH :

Ummmm not so easy haha, especially 6-speeds. The prices are climbing too. I lucked out I don't think the PO knew how much they go for. It's a 2011 with 172k I paid $7000 but comparable cars were going for $10k+. Also the manuals are super hard to find in the first place.

J1000 said:

 

First things first I got this little gizmo from Peter Perkins called the OBDIIC&C. It plugs in to the OBD port and can show all the battery and IMA system stats like voltage, amperage from battery, motor amp draw, 12v system voltage and draw, battery temperature etc etc. Really cool. It also measures the Usable Capacity and State of Charge (SoC). It also can force the battery SoC to low, medium, or high. In this way you can force the car to think it has a full battery and give maximum assist power for a short period of time (2 minutes or so) or you can force it to think the battery is very low and it will start charging the battery at idle. With these tricks you can slightly overcharge the battery and discharge it further than the car would otherwise allow. At the moment it provides minimal benefit, but with a custom battery it can unlock more performance.

In R/C, we used to call this "Pushing" the cells.

J1000 said:

In reply to daytonaer :

Yeah well unfortunately that's what I got  

The HPD stuff is cool but expensive. I'd rather have a turbo than centrifugal blower also. I'm not so much "going for revs" as just gaining a little breathing room. I want to autocross and it's going to be useful there too. 7000RPM is plenty I think.

 

Sorry, by "fix" I meant artificially, with boost :-)

I have created an example of how one should NOT autocross a crz:

I've always loved these cars. I had a friend plow a bunch of money and time into one a while back. He ended out K swapping it in the end.

He moved across the country and parted it out to fund that.

Below is a link to his build

https://www.crzforum.com/threads/rustbuckets-build-thread.14083/

Will be following along.

In reply to daytonaer :

Haha nice! I am excited to try some auto-x I'm pleased with the handling. I had an EP3 before and the CR-Z seems to be about the same in acceleration but much, much better handling even stock with a lot of miles. 

In reply to R32Jordie :

That thing is sweet! I'm not going to lower mine at all the front bumper overhang is way too long and it scrapes on everything. I'm wondering if any bodykits have a shorter overhang or possibly the '16 model which has different bumpers.

I have some more hop-up parts for my Z. I searched around for cams and found a Cat Cams camshaft. It was supposed to take 2 months for delivery but ended up taking only a few days! So I wasn't ready for it and it's still on the shelf. I also got a Supercircuit header and midpipe to install to complete the exhaust.  I took the header in to get a ceramic coating, damn it looks nice!! They did inside and out. I'm a true believer in ceramic coating exhaust parts.

I am going to install both tomorrow as I have scheduled a dyno session for next week!

My Cat Cams camshaft p/n: 2503201 This is their "Sport street" cam for road cars so nothing too crazy.

Neither Cat Cams nor the company I bought it from gave me any break-in instructions for it. I've gotten custom cams before and usually they prescribe something. I am going to smear it really well with fresh oil before I install it and change the oil after a couple miles I think. If anyone has any other advice I'd be open to hearing it. I will let the dyno guy find the best RPM for VTEC changeover. 

Was a big day today!

Got my cam and exhaust installed and got to use my MCM fender guards for the first time! 

Got the valve adjuster nuts replaced with titanium ones. Hell yeah racecar! They are 2g lighter on my cheap scale that doesn't measure tenths. 2g x 16 = 32g of reciprocating valvetrain. Not nothing.

Used these nuts: https://amzn.to/323tqYf

And of course the beautiful downpipe:

It is much louder! Sounds really smooth though. I will have to take some videos.