domesticated : 1993 Accord SE

[Domesticated]

I'm looking for a functional baffled catch can for around 100 or less, any recommendations?

[Domesticated]

Scales are here, I don't have time to measure the car tonight, hopefully tomorrow. Really curious to see where my weight is currently at. Started at 2955 with full interior. Way heavier than I expected lol. I figure I still have another 100lbs I can take out. (rear door glass and motors, a lot of sound insulation, and swapping out carbon components)

[baracuda]

Scales are here, I don't have time to measure the car tonight, hopefully tomorrow. Really curious to see where my weight is currently at. Started at 2955 with full interior. Way heavier than I expected lol. I figure I still have another 100lbs I can take out. (rear door glass and motors, a lot of sound insulation, and swapping out carbon components)

I'm curious to see what weight distribution comes in at, 2955 does seem up there since Wikipedia has it set at ~2700lbs. I wonder if that weight is official from Honda(as everyone claims the coupe weigh more then the sedans.), or if we can find what the official claimed curb weight from Honda when it went on sale.

[Domesticated]

I borrowed a set of scales two years ago before I stripped the car and it weighed 2955. The distribution is somewhere on a previous post in this thread, possibly September of 2014.

I have data from where a CB was measured by my work 25 years ago. Don't remember the model, but it had 14s and no rear bar and it weighed 2877 completely stock.

[Domesticated]

My current weight is

773 749 60.2%
515 492 39.8%
50.9% 49.1% 2529

I still have 50lbs in rear door windows and a whole bunch of sound insulation. Bit that's 426lbs dropped.

[Domesticated]

[Tishock]

Yes the red ones. Also the axles! The coil overs are currently FnF and the rear lowers are FFC (I've actually seen the weights of those posted somewhere).

[Domesticated]

Thanks!

Some updates on my maths. I measured all the kinematic hard points in the suspension and updated my ride frequency calculator.

I measured a few more parts, but the way the math works out 20lbs of added corner weight only changes the ride frequency by 0.02Hz, so I think my figures are close enough.

By the data I have from an SPMM test my company ran when the Accord was new (data can be found in my signature) and my calculator, the stock ride frequency was 1.19 front and 1.52 rear with a ride ratio of 1.27 and spring rates of 37N/mm front and 32N/mm rear. These numbers make a ton of sense as my current prototype at work rides a lot like a stock CB and it's ride numbers are nearly identical.



So given my vehicle weights, corner weights, tires, and springs from the FnF coilovers, my numbers are:
Ride Data
Tire rate--------------------- 12000 lbf/in - 2101.5 N/mm
Front Spring Rate ------------- 670 lbf/in -- 117.3 N/mm
Rear Spring Rate-------------- 335 lbf/in ---- 58.7 N/mm
Effective Front Spring Rate--- 415 lbf/in ---- 72.7 N/mm
Effective Rear Spring Rate---- 231 lbf/in ---- 40.4 N/mm
Front Ride Rate---------------- 401 lbf/in ---- 70.2 N/mm
Rear Ride Rate----------------- 226 lbf/in ---- 39.6 N/mm
Front Natural Frequency------ 2.34 Hz
Rear Natural Frequency ------ 2.19 Hz
Ride Ratio---------------------- 0.94

These rates are high for the weight of my car if it were a street car. They are on the low end of tuning a car for pure mechanical grip with no aid of aero for what my car used to weigh. The ride frequency drops by 0.20Hz with the stock weights. I think I'm going to multiply the original ride frequencies by 2, but keep the ride ratio the same. The ride ratio of this setup is pretty terrible, which explains why the car feels so unbalanced.

I'm going to double check my measurements, but it looks like I'll go with the Eibach 700lb/in fronts and 650lb/in rears

Ride Data
Tire rate ------------------- 12000 lbf/in - 2101.5 N/mm
Front Spring Rate ------------ 700 lbf/in -- 122.6 N/mm
Rear Spring Rate ------------ 650 lbf/in -- 113.8 N/mm
Effective Front Spring Rate - 434 lbf/in --- 75.9 N/mm
Effective Rear Spring Rate --448 lbf/in --- 78.4 N/mm
Front Ride Rate ------------- 418 lbf/in --- 73.3 N/mm
Rear Ride Rate -------------- 432 lbf/in --- 75.6 N/mm
Front Natural Frequency --- 2.39 Hz
Rear Natural Frequency -----3.02 Hz
Ride Ratio ------------------- 1.26

[baracuda]

Thanks!

Some updates on my maths. I measured all the kinematic hard points in the suspension and updated my ride frequency calculator.

I measured a few more parts, but the way the math works out 20lbs of added corner weight only changes the ride frequency by 0.02Hz, so I think my figures are close enough.

By the data I have from an SPMM test my company ran when the Accord was new (data can be found in my signature) and my calculator, the stock ride frequency was 1.19 front and 1.52 rear with a ride ratio of 1.27 and spring rates of 37N/mm front and 32N/mm rear. These numbers make a ton of sense as my current prototype at work rides a lot like a stock CB and it's ride numbers are nearly identical.



So given my vehicle weights, corner weights, tires, and springs from the FnF coilovers, my numbers are:
Ride Data
Tire rate--------------------- 12000 lbf/in - 2101.5 N/mm
Front Spring Rate ------------- 670 lbf/in -- 117.3 N/mm
Rear Spring Rate-------------- 335 lbf/in ---- 58.7 N/mm
Effective Front Spring Rate--- 415 lbf/in ---- 72.7 N/mm
Effective Rear Spring Rate---- 231 lbf/in ---- 40.4 N/mm
Front Ride Rate---------------- 401 lbf/in ---- 70.2 N/mm
Rear Ride Rate----------------- 226 lbf/in ---- 39.6 N/mm
Front Natural Frequency------ 2.34 Hz
Rear Natural Frequency ------ 2.19 Hz
Ride Ratio---------------------- 0.94

These rates are high for the weight of my car if it were a street car. They are on the low end of tuning a car for pure mechanical grip with no aid of aero for what my car used to weigh. The ride frequency drops by 0.20Hz with the stock weights. I think I'm going to multiply the original ride frequencies by 2, but keep the ride ratio the same. The ride ratio of this setup is pretty terrible, which explains why the car feels so unbalanced.

I'm going to double check my measurements, but it looks like I'll go with the Eibach 700lb/in fronts and 650lb/in rears

Ride Data
Tire rate ------------------- 12000 lbf/in - 2101.5 N/mm
Front Spring Rate ------------ 700 lbf/in -- 122.6 N/mm
Rear Spring Rate ------------ 650 lbf/in -- 113.8 N/mm
Effective Front Spring Rate - 434 lbf/in --- 75.9 N/mm
Effective Rear Spring Rate --448 lbf/in --- 78.4 N/mm
Front Ride Rate ------------- 418 lbf/in --- 73.3 N/mm
Rear Ride Rate -------------- 432 lbf/in --- 75.6 N/mm
Front Natural Frequency --- 2.39 Hz
Rear Natural Frequency -----3.02 Hz
Ride Ratio ------------------- 1.26

I know some of these word . So what I gather is this setup for your car would make it ride almost as comfortable and true as stock while being more aggressive in handling? Are you planning on pairing the FnF shocks & sleeves with the eibach springs and do you expect any fitment issues if so? This is by far one of the most legit setups I have ever seen come through the accord tuning crowd, your education and work history put you in a very unique position. Thanks for sharing

[Domesticated]

Warning: Huge generalization ahead. The ride frequency is a rough estimate of comfort. Tire and dampers also matter a lot, but the lower the ride frequency the better potential you have for ride comfort, but inherently worse handling.

Upping the ride frequency makes the car ride much stiffer and increases harshness. It will ride much worse than stock. It will also increase steering efforts a bit. But, keeping the ride ratio as close to stock should make the car feel about as balanced as original. There are two big assumptions here, my measurements are all accurate within reason (which I believe them to be), and the original ride ratio had the balance I'm looking for. Starting at the original ride ratio will be a better starting point than picking random springs. It may not be what I want or need, but the Honda engineers did do a lot of work so I'll start there.

I will be offloading the FnF dampers most likely. The spring balance is crazy wrong and if I assume the dampers were actually developed for those spring rates then they will also be wrong for what I need. My final coilover setup will be:

Bilstien B6 Monotubes converted to take aparts
Penske Valves and Pistons (I'll do my own damper tuning)
Eibach main spring (not sure on diameter or length yet, need to talk to ground control but I'm guessing 2.5" OD and 7" length)
Eibach Coupling Spacers
Eibach Helper Springs (so I can retain rebound travel)
Ground Control Sleeves

Not sure what I'm going to do about the top mount just yet.

I'm considering make a coilover kit tuned specifically for CB's. Choosing spring rates will be easy, but I'll need a donor car to actually do the damper tuning on for each package available.

[Domesticated]

After talking with the Viper Dynamics engineer, I need to revise my ride frequencies for my car and not keep the original ride ratio. I'll update later when I can find some information I need.

[Grumpys93]

I feel like I'm too dumb to read your thread. I love the research your doing for our chassis, I plan to really concentrate on your thread this Sunday while I'm on a 24hr watch. Hopefully I can understand what your saying, because this is for sure interesting stuff.

[Domesticated]

A ride ratio of 1.1-1.2 is preferred for running a street car because most ride events occur at 50-70 mph. I'll want a ride frequency closer to 1. It's gonna ride like shit on the street, but will be balanced at 100-120mph.

Today I got the power steering working without leaking, the ride heights adjusted, and the alignment dialed in. Conveniently for me I have Pilot Super Sports and the end of the measuring tape fits tightly in one of the little sipes in the tread. I get accurate repeatable measurements. Buttoned up a few odds and ends and then went to do a tuning run. Laptop is dead lol. Gotta charge it first then onto tuning.

[Domesticated]

She's coming along great! Slowly working out all the little kinks. But suspension is aligned and ride heights set. Power steering is working better than ever (new rack, rebuilt pump, I need OTRs and I either need to tighten the yoke or replace the I shaft. Did some tuning. Map is cleaning up very well! Once I get it as close as I can I'll take it to a tuner to have the spark and fuel fine tuned. Today was an awesome day. For the first time in two years my car just "worked". A lot of work coming together.

[Raf99]

She's coming along great! Slowly working out all the little kinks. But suspension is aligned and ride heights set. Power steering is working better than ever (new rack, rebuilt pump, I need OTRs and I either need to tighten the yoke or replace the I shaft. Did some tuning. Map is cleaning up very well! Once I get it as close as I can I'll take it to a tuner to have the spark and fuel fine tuned. Today was an awesome day. For the first time in two years my car just "worked". A lot of work coming together.

Great news man! Hey, do you know if I can hook a laptop up to my S300 and simply pull the "map" (file) down from the ECU?