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Discussion Starter · #41 ·
Surely the best way to restrict power is by tuning the vtc? It's all ready there, Fully variable and really effective.
i have a 200hp cap. Every 1hp i'm over, i need to carry 18lbs. Im under weight... precision and consistency is the key.

I need to hit 200hp as soon as possible and carry it as long as possible... SCCA STL K20Z3 legal motors still make +225hp (they have less lift, more duration cams... more compression, and a 44mm restrictor plate)

In the 8th gen there are several ways to detune (or a combination of ways to detune)... its DBW, so you can dial down the throttle body flap opening by rpm, you can restrict VTC, you can restrict timing, and/or you can run a restrictor plate.

If i rent a dyno for the day... i'm going to try every single way to get the best power curve possible. A restrictor plate is a tool in the tool kit... takes under 10 minutes to layout and cut 6 of them. takes a minute to swap out on the dyno.

yes... i have spent an entire day swapping headers and intakes on the B18C5... getting tuned... to find the best power curve my car can make. you can bet the farm i will do the same with detuning this car.

At the end of the day, my tuner (tunes a lot of road race car) said "you need to make some restrictor plates at 60, 58, 56, 55, and 54mm" ... so i do it.
 
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Exceptional build quality. Keep up the good work!

Peter
 

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i have a 200hp cap. Every 1hp i'm over, i need to carry 18lbs. Im under weight... precision and consistency is the key.

I need to hit 200hp as soon as possible and carry it as long as possible... SCCA STL K20Z3 legal motors still make +225hp (they have less lift, more duration cams... more compression, and a 44mm restrictor plate)

In the 8th gen there are several ways to detune (or a combination of ways to detune)... its DBW, so you can dial down the throttle body flap opening by rpm, you can restrict VTC, you can restrict timing, and/or you can run a restrictor plate.

If i rent a dyno for the day... i'm going to try every single way to get the best power curve possible. A restrictor plate is a tool in the tool kit... takes under 10 minutes to layout and cut 6 of them. takes a minute to swap out on the dyno.

yes... i have spent an entire day swapping headers and intakes on the B18C5... getting tuned... to find the best power curve my car can make. you can bet the farm i will do the same with detuning this car.

At the end of the day, my tuner (tunes a lot of road race car) said "you need to make some restrictor plates at 60, 58, 56, 55, and 54mm" ... so i do it.
If your tuner can't make a power curve that hits 200hp asap and stays their until it runs out of puff just by tuning the vtc table and ignition curves then in not sure what else they're missing.
 

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Discussion Starter · #44 ·
Exceptional build quality. Keep up the good work!

Peter
thanks... I spent a lot of time in the NASA tech shed talking to car builders and racers... I read a lot of Race Car Engineering and Grassroots Motorsports magazines... and with limited time to work on the car I have a lot of time to think about what i'm doing and plan it all out. There is a lot more to come. Right now things are just in place, nothing is finalized... and i'm a little over the wire routing... i need to clean that up.

If your tuner can't make a power curve that hits 200hp asap and stays their until it runs out of puff just by tuning the vtc table and ignition curves then in not sure what else they're missing.
I dont disagree... but if the tuner wants restrictor plates, you bring them. we have all day to figure out the best combination for the best power band.
 
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Discussion Starter · #45 ·
I tend to get a lot of questions about aero. I watch a lot of AJ Hartman and Race Louver youtube videos... No these are not Race Louvers, because i had to find the right dimensions for my car...

This test was done on the 8th gen civic by Norman Hayton (not me!) and confirmed by Nick Khors... the key is knowing the low pressure spots on your hood AND its relationship to your radiator.
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6 inches back on the hood, thats about flush with the radiator (i actually need to measure... because i know the fill neck is 2 inches or so from the back of the radiator. These are 6 inch grids FYI. Having it in front of the radiator does you zero good... so you need to look for the low pressure spot "at least" behind the radiator, if not 2-4 inches behind it, if possible. Sealing the core support and ducting the radiator improves things drastically...

in my old car i gained +5* of cooling and gotmore front down force (unmeasured) that seemed more consistent from lower speeds to higher speeds.
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Nicks beast mode car... he's been a wealth of information for my transition to this car.
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I think it will make over 200 with no vtc still. Most guys who have to limit power do it by TB restrictor plates.
The problem with a restrictor is your restricting the entire torque curve. The brilliance of the vtc is you can lower the volumetric efficiency in specific areas of the power band and still have optimized torque everywhere else.

If absolutely necessary you could retard the intake cam one whole tooth on the chain then you'll definatly be able to drop below 200hp with that much vtc retard. It would give you a usable vtc range of -15 to 35 degrees.

More valve- piston clearance and a huge VE reduction at -15 degrees cam timing.

Of course you'd need a full stand alone ecu to support this vtc range. I don't think any of the piggy back boards would be this adaptable.
 

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Discussion Starter · #48 ·
The problem with a restrictor is your restricting the entire torque curve. The brilliance of the vtc is you can lower the volumetric efficiency in specific areas of the power band and still have optimized torque everywhere else.

If absolutely necessary you could retard the intake cam one whole tooth on the chain then you'll definatly be able to drop below 200hp with that much vtc retard. It would give you a usable vtc range of -15 to 35 degrees.

More valve- piston clearance and a huge VE reduction at -15 degrees cam timing.

Of course you'd need a full stand alone ecu to support this vtc range. I don't think any of the piggy back boards would be this adaptable.
restrictor plates are just a tool in the kit for when we go to the dyno. i didnt have restrictor plates before, but i did pull my 62.5mm TB and put the stock 62mm TB on in the end... with the .5mm extra TB we couldnt keep the motor (B18C5) under 190hp without jacking up the curve.

I have an ECU restriction as well... they arent letting us go to full stand alones yet... H1 is the test bed for that rule change.
 

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Discussion Starter · #49 ·
Also i realized i didnt post my most useful modification to date (you know because its just sitting in the garage)... the stock hood prop is 100% in the way of everything and i shouldnt have to worry so much with it on windy days in the paddock.

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restrictor plates are just a tool in the kit for when we go to the dyno. i didnt have restrictor plates before, but i did pull my 62.5mm TB and put the stock 62mm TB on in the end... with the .5mm extra TB we couldnt keep the motor (B18C5) under 190hp without jacking up the curve.

I have an ECU restriction as well... they arent letting us go to full stand alones yet... H1 is the test bed for that rule change.
Hey its your project, I'm just thinking about how i would achieve the best results with the limitations.

B18c has more limitations, no dbw, no vtc. You're more limited to mechanical restrictions to limit power.

I like your pressure/vacuum distribution testing. It's nice to see real world results like that. Interesting to get positive pressure half way up the Bonnet/ guard intersection. I wonder if that's something to do with the air escaping through the gap there.

Is your tube inside the boundary layer? How do you make sure the venturi effect isn't skewing your results?
 

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Discussion Starter · #51 ·
Hey its your project, I'm just thinking about how i would achieve the best results with the limitations.

B18c has more limitations, no dbw, no vtc. You're more limited to mechanical restrictions to limit power.

I like your pressure/vacuum distribution testing. It's nice to see real world results like that. Interesting to get positive pressure half way up the Bonnet/ guard intersection. I wonder if that's something to do with the air escaping through the gap there.

Is your tube inside the boundary layer? How do you make sure the venturi effect isn't skewing your results?
I didnt run the test... i was going to run the test before i dismantled the car (i had a couple of weeks to get the car ready for the cage work before surgery... time was tight), but i found +4 identical tests on the 8/9th Gen Race Group... they all produced nearly identical results (with different measuring devices), so they either all made the same mistakes or the mistakes impacted things minimally... so i opted not to do the tests on my actual car.

reviewing the data from AJ Hartman and Race Louvers youtube channel.... the data also seems to align with that they have to say. Obviously they arent using 8th gen coupes, but the theories are the same.

SO... using the preponderance of evidence, i made an educated decision on where to place my louvers/vents.
 
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i need to clean that up.
but if the tuner wants restrictor plates, you bring them. we have all day to figure out the best combination for the best power band.
This 200 hp class rule is a hard challenge, depending on how it is tested. The influencing parameters are test bench, weather conditions: humidity, atmospheric pressure and as well the engine and fuel stuff. To give you an example, the difference of 30 and 100 % humidity at same pressure is around 3-4 lbft across engine speed bandwidth on a 2 Liter engine. I've seen on the same location pressure differences of 0.05 bar (0.725 psi). This is like having an engine at 95 % load instead of 100 %. An engine be set on spot to 200 hp without any risk of deviations. So the layout of it must be conservative with an decided offset to 200 hp.

I see like you following options for the tuner and priority:
  1. engine speed limit, full unrestricted torque until 200 hp - offset, fastest, safest, not best for straight's
  2. restrictor plate, restricted torque all over until 200 hp - offset, takes time to find, to set properly and cost increasing torque with increasing engine speed
My recommendation for offset to be safe on various test benches and weather conditions would be 7 hp or less, depending on the tuning weather conditions and a likely location of a NASA retest.

I would not going to use the VTC for following reason. The difference between 30 and 20 degree VTC at the end of the engine speed bandwidth (in the middle the difference are some 10 lbft, sometimes 90 % on the left side of high speed cam) are a few lbft and depends highly on exhaust temperature (= combustion speed = humidity). You would need to retard it hard and far down to meet the 200 hp limit. The VTC is PID closed loop controlled, reacts on different engine speed gradients differently. Low gear WOT shifting can get challenging with that as a limiter, especially when you shift faster then VTC turns back to setup value. I tune race engines with an piloting VTC advance during the shift event to have full torque back when next gear is in (around 40-60 ms), VTC needs around 10 ms for 10° on a stock ECU PID setup and SAE30 oil in warm condition. So piloting is necessary. When you retard it for peak power control it may be smoother then an engine speed limiter, but can give you a PITA on some slower tracks. I know, in theory the VTC is a perfect torque (= correspond to power over engine speed) controller, but in reality it is not precise and fast enough to utilise a fun to drive and responsive race engine. Most stock near K20 engine setups turn VTC in beyond 5800 rpm from 50° down to around 20° at around 7800 rpm or so. The limit on a stock near engine for 200 hp at flywheel may be reached around 6500-7000 rpm, which would mean to turn in at around 40°, which is not too bad for a VTC controlled torque limit. If the limit is rated at wheels, the story looks different as the turn in to limit peak power of VTC would happen around 7800-8000 rpm, where VTC is very insensitive and need a bigger amount of pilot control.

The other point is confirmation of the 200 hp limit. Do they trust you when you set engine speed e.g. to 7500 rpm, do they want to put the calibration under seal? Do they just need a print out of any dyno or a specific dyno? Do they need to have an attestor or not? The more they need, the easier the engine speed thing is to setup, as it is the fastest, safest and easiest. Your tuner should know this.
 

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Discussion Starter · #53 ·
Since you guys are a wealth of knowledge... here is the overview of what happens.

1. place high enough in a race or get randomly pulled (i'll get "randomly" pulled because i have complained about the following) and you go to the dyno for a compliance check.
2. The dyno will be a Dynojet using a SAE correction factor and smoothing of "5"
3. The results will be from the average of 3 pulls.
4. The hood must be open, the tires must be at 33psi, the car must be at an operating range of 160-210* (they will shut the car down if it goes over 210), they will use 4th gear or at a 1:1 ratio gear
5. Pulls are made from 2500 rpm to rev limit... if no rev limiter is present, the driver must declare a red line and the graph must show a declining curve at or just beyond that point.

My issue with the dyno rules:
5.10.5 states "Dyno pulls will be made in 4th gear or at a 1:1 ratio." ... there is no rule that says "the driver must ensure compliance in all other gears." The spirit of the rules is to be compliant in all gears, but it doesnt say you have to be.

On a B series car, its is very obvious that the 1:1 ratio is also 4th gear. In a K series car 1:1 is 5th gear... so with this rule i can be checked in either 4th or 5th. I KNOW people are tuning by gear, I had to do it with my B series car to be compliant in every gear... but I also have video that proves to me, my competitors are only compliant in 4th gear and they are over tuning at least 3rd and 5th. My tuner is also a racer, he will not let me only be compliant in 4th. I submitted a rules change request (that was denied with no reason given, they never give a reason) so i think they will dyno me after my first time out in the car... "randomly"
 
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Discussion Starter · #54 ·
Because of my gearing dilemma and covid 19 shortages of parts... I've had to cast a WIDE net to get parts and get things lined up. my DC5R gearing is from a 05-06 (thanks afhkparts.com , Ryan knows his stuff)... so that opens up the door for me to run the 5.46 FD instead of the 5.84 I was going to run with the Type S 6th ... i was able to find the 5.46FD at a new company Hybrid Hypersport ( Hybridhypersport )... so very fortunate to have friends of friends reaching out on my behalf!

I've purchased maybe $60 worth of parts from Tall Pines Racing (Tall Pines Racing) ... and he's spent too much time with me going over transmission options... but he is about to get my gear set for cryo and micropolishing... and i'll be ready to rip.

I feel very fortunate to have sponsors of friends willing to help out... its humbling to say the least.
 
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Discussion Starter · #55 · (Edited)
We had some surprise family guests this weekend so i didnt get everything ecomplished that i wanted to... such is life. I need to take advantage of every opportunity to get things moving and just enjoy the times with family in the mean time.

this car takes A LOT more work to get the engine out... Its either drop the subframe and send it out the bottom or pull stuff and get it out of the top. well i needed to pull the front end anyway... i'm measuring for the splitter mounts and installing aerocatch hood latches... SO we are going to try it out of the top. The biggest pains were the axles and the header... everything else is pretty straight forward... but with a engine harness with 3 times the plugs as a B series and a starter that has to be removed to unbolt the big wire... you know, no biggie.

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Honestly i'm 1 axles and two mounts away from removing it... the axle was being a pain and i was tired at this point... and i think i want to buy a new/modify my cherry picker leveler for this car... just to make life easier.

To get a sense of accomplishment and work a little easier i moved to the back of the car to semi wrap that section up. I need to route and plug in the brake light harness, mount the r*&n light, and wire up the battery.
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Pro Tips... every hole you drill, you need to seal with paint. Every time something can touch the paint... i wrapped in electrical fabric tape. These are also long bodied remote reservoirs ... so i decided to add some fuel tubing to reduce the contact and vibration to the body. Its not "facny" but it will do the job pretty well!
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Discussion Starter · #57 ·
A little light reading material for the holiday weekend... I doubt i'll get much done with the car but you never know when your kid brother (former Porsche mechanic) comes into town.

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Discussion Starter · #58 ·
Public Service Announcement: Diabetes is bad... do whatever you can to avoid it.

I spent most of the weekend adding hand rails to my inlaws home because my FIL lost a toe to diabetes. So not a lot of time on the car. BUT I did spend some quality time in the garage, thanks to my wife and her understanding!

I learned several things with my other car... one of them is plan out your use of lexan/poly methodically. second is... use rivnuts and not pop rivets. track side lexan removal should be as easy as possible and in a manner that shouldnt possible damage the lexan as its expensive.

The rear glass is the worst to do... it will take the longest to plan. you want to make sure you arent popping too many pinch welds and that you are putting rivnuts (or pop rivets if you really want) into flat metal. As always, seal your drilled holes with paint... AND if you use rivnuts, practice on flat metal and make sure your settings are good on your rivnut or pop rivet gun.

One of the biggest challenges of the rear glass is how to attach it along the bottom. Its a very thin metal, its not flat or large... missing or measuring incorrectly is easily done. On this car i decided to rivet aluminum tabs in to hold my rivnuts. it will give me a uniform look and make it easy to remove the glass if needed (and yes i have had to do it)
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This is what the rivnut should look like when compressed...
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If you are paranoid like me... or have ever had to deal with a failed rivnut... you add a little JBweld to the base so it wont fail after your race car shakes them to death.

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Also to match... i did rivnuts for the hood vents. yes i used a lot of rivnuts, but the shape of the hood dictated that. I'll post more pics once this snow goes away.
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I did some other things... like build the mount for the fire suppression bottle and remove my wing for sanding and painting... no... i dont have any pics of that yet. maybe later.
 

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Discussion Starter · #59 ·
I almost forgot... i made some changes sunday night after a conversation with a friend running Honda Challenge H1 with a K series hatch... he confirmed some things that some of the GLTC guys have noticed with their 8th gens.

I ordered U88A hasport inserts and the Unit 2 weld it yourself baffle system. I will be using it instead of the TracTuff baffled 9th gen pan. I need the U88A stiffness as I wont be utilizing the rear pan mount.
 

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The generation civic you have has a oem metal plate that goes to the upper front strut towers. I bought that oem piece for $5 just to have in case if I could recreate it but stronger. Since you have a cage installed, stitch welding in certain areas maybe something to entertain once you have everything up and running. Of course it would have to be determined if it is actually needed or not.

Project build is looking good bro.
 
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