Black & Green modding thread (1998 Civic DX Coupe base)

[jedi_sol]

Originally Posted by Vansquish

I applaud your efforts at improving your fuel economy, but unfortunately you've also created a car that is an extremely dangerous device for you and others around you on the road.

1. Your tire inflation pressures are 15-25psi over the acceptable maximum inflation pressure limit for any 175/50/13 or 175/70/13 tire on the market. That's a blowout waiting to happen. The highest available 175/50/13 or 175/70/13 maximum pressure for any tire of the sort on the market is 44psi, fyi.

2. Your lowered suspension, despite improving your aero-capabilities make it much more likely that if you do end up in a collision, you will not survive unscathed. Your crash-bar height at the front, at the rear, and as far as the side-impact beams are concerned is now significantly lower than that of the vehicles around you. The net result is that if you have a crash, your car will effectively pass partially underneath the other car in the incident, drastically increasing the likelihood of serious injury or fatality for you and your car's other occupants.

Us eco modders like to live in the danger zone.

[California98Civic]

Originally Posted by jedi_sol

Us eco modders like to live in the danger zone.

Mwhahahahaha!! "Look ma! ... both hands, and slow!"

[Vansquish]

If your suspension hasn't been modified, then your wheels are having similar impact on your crash-bar height.

A 175/50/13 tire should have a height of about 19.9", or more usefully, a radius of 9.95". The original wheel/tire package on your car was a 185/65/14, meaning a diameter of 23.5" (radius of 11.75").

So, what does this mean? Obviously you're playing the semantics game. OK, your suspension hasn't been modified, but you've effectively lowered your car by slightly less than 2 inches (11.75-9.95=1.8"), thus lowering your crash bar height by an equivalent amount.

I'm not arguing that you're a bad driver, or that you're driving in an unsafe manner, I'm suggesting that the car itself is no longer able to withstand impacts the way it was designed to.

The most likely (and problematic) impacts are the ones over which you have no control.

As for the overinflation, I'm sure the subject has been discussed ad nauseum on here, so I'm sure you have a reasonable basis for your argument. My justification for saying that your 60psi over-inflation is unsafe was based on the listed maximum inflation pressures, for the tire type, size, speed-rating, and load capacity.

Additionally, with a tire so over-inflated, your braking distances will be negatively impacted, as will your ability to make evasive maneuvers if necessary. Of course, some of this will be negated by the fact that you're running smaller-diameter wheels which carry less angular momentum and less lateral inertia.

[jedi_sol]

Dont know why you keep picking on California98Civic? if you browse all of the project cars on this form with your frame of mind, you're going be in for a HUGE SUPRISE.

all of the top mpg achievers on this site employ the same tactics: lowering the car, gutting the interior, over inflating tires, etc....

are you going on their threads slapping their wrists too?

are these tactics safe? no they're not safe, but like California98civic says, texting or driving while on the cell phone and speeding is more dangerous to everybody on the road.

[California98Civic]

Originally Posted by Vansquish

If your suspension hasn't been modified, then your wheels are having similar impact on your crash-bar height.

A 175/50/13 tire should have a height of about 19.9", or more usefully, a radius of 9.95". The original wheel/tire package on your car was a 185/65/14, meaning a diameter of 23.5" (radius of 11.75").

So, what does this mean? Obviously you're playing the semantics game. OK, your suspension hasn't been modified, but you've effectively lowered your car by slightly less than 2 inches (11.75-9.95=1.8"), thus lowering your crash bar height by an equivalent amount.

I don't know what you game is, but again, you simply are not reading at all, or are reading poorly. The tire size you list is not my tire size. My front tires are the stock 185/65-14s. So your point is moot. It's not semantics to point out that you're wrong on the basic facts.

Jedi-sol here offers you some good advice:

Originally Posted by jedi_sol

if you browse all of the project cars on this form with your frame of mind, you're going be in for a HUGE SUPRISE.

all of the top mpg achievers on this site employ the same tactics: lowering the car, gutting the interior, over inflating tires, etc....

are you going on their threads slapping their wrists too?

If you don't mind, "Vansquish," maybe you could take your critiques of lowered suspension onto a thread for a car that actually is lowered? I'd like to have my build thread back.

[Blue Angel]

Subscribed!

There's some great info here and I can't wait to see the results of your on-going testing. My Cruze is a sedan body style as well, so your results with the box section are particularly interesting. It weighs about 1000 lbs more than your lightened Civic, so the only way it even stands a remote chance of keeping up with your car would be on the highway... around town your car must be pretty efficient!

Interesting that your 5-speed VX transmission gives you 2.4% taller OD gearing than my 6-speed Eco. Your 0.702 5th and 3.250 final give you 2.2815 vs. my 0.61 6th and 3.83 final at 2.3363. The Cruze has a very short 1st gear though, kina necessary given the small 1.4L engine and relatively high curb weight.

Funny that Honda learned the high gear ratio trick so long ago, and their current fleet of Civics has such short gearing...

[California98Civic]

Originally Posted by Blue Angel

There's some great info here and I can't wait to see the results of your on-going testing.

Cool. I got the rails I need for the bellypan, taking jedi_sol's suggestion in post #16. And I have some left over wood baseboard trim I'll use to supplement. And I recently installed these Raybestos H6001 brake drag reduction clips. I like 'em, but I don't know how much of a benefit they really are. A certain brake drag sound during EOC is gone, though:

Originally Posted by Blue Angel

My Cruze is a sedan body style as well, so your results with the box section are particularly interesting. It weighs about 1000 lbs more than your lightened Civic, so the only way it even stands a remote chance of keeping up with your car would be on the highway... around town your car must be pretty efficient!

If I am willing to very radically hypermile, I easily cross 70mpg on the city streets. But the taller gearing of the '93 CX/VX transmission, in truth, is not as ideal for city P&G as the shorter first three gears of the '98 DX trans were. I suspected as much, but I really wanted the capacity to cruise on the freeway more. Occasionally, it has seemed attractive to me to experiment with swapping individual shorter gears into my DX trans, as I play with the extra VX final drive I plan to try and swap into it. But I have a big learning curve ahead for just the FD swap, so ...

Originally Posted by Blue Angel

Interesting that your 5-speed VX transmission gives you 2.4% taller OD gearing than my 6-speed Eco. Your 0.702 5th and 3.250 final give you 2.2815 vs. my 0.61 6th and 3.83 final at 2.3363. The Cruze has a very short 1st gear though, kina necessary given the small 1.4L engine and relatively high curb weight.

Totally interesting. I did not know the Cruze Eco gearing was THAT tall. And they sqeeze 138 hp outta that 1.4L. I was already interested in the little car, now I'll have to obsess over it a little this evening.

Originally Posted by Blue Angel

Funny that Honda learned the high gear ratio trick so long ago, and their current fleet of Civics has such short gearing...

I know, right? So disappointing. But I think part of the explanation is the US market's drivers, who expect "power." To some degree, they gear the manuals short in order to sell to people with the fantasy of a street racer in their heads. Another part of the explanation might be that they have been increasing the tire/wheel sizes steadily on the civic. In 1993 the VX/CX came with 165/65-13s (or something close to that) and the new Civic comes with 195/65-15s, which makes the effective gearing quite a bit taller. And the HF does not come in a manual (another bummer). It's standard, conventional automatic has some fairly tall gearing though (0.525 fifth and 4.44 FD).

james

[Blue Angel]

Originally Posted by California98Civic

And I recently installed these Raybestos H6001 brake drag reduction clips. I like 'em, but I don't know how much of a benefit they really are. A certain brake drag sound during EOC is gone, though

I'll have to check into those! Do you find you have any extra pedal "take-up" or slop after installing them?

Originally Posted by California98Civic

If I am willing to very radically hypermile, I easily cross 70mpg on the city streets. But the taller gearing of the '93 CX/VX transmission, in truth, is not as ideal for city P&G...

70 MPG? WOW

P&G isn't advised with a turbo engine since shutting down under power leaves the turbo spinning at speed in a HOT housing, with no oil flow to lubricate the bearing and no coolant flow to cool the housing... not a good plan for long term reliability.

Originally Posted by California98Civic

Totally interesting. I did not know the Cruze Eco gearing was THAT tall. And they sqeeze 138 hp outta that 1.4L. I was already interested in the little car, now I'll have to obsess over it a little this evening.

Yep, that super tall 6th is the Eco's trump card. The standard Cruze manuals come with a 0.74 6th gear, same as the Eco's 5th gear.

Now that you mention tire sizes, the Eco has a 26.3" tall tire (215/55-17), so the effective gearing is pretty tall. At 60 MPH that little turbo motor is only spinning ~1857 RPM.

Originally Posted by California98Civic

I know, right? So disappointing. But I think part of the explanation is the US market's drivers, who expect "power."

When I worked for Transport Canada we had an Acrua EL (fancy Civic) that would rev 4000 RPM at 120 km/h (75 MPH)!

[California98Civic]

Originally Posted by Blue Angel

I'll have to check into those! Do you find you have any extra pedal "take-up" or slop after installing them?

No extra pedal take up that I have noticed, but I was not paying attention. They're ridiculously easy to install. But even easy is too hard if they're not effective. And I just can't know for certain. Seems logical that they benefit at some level.

[jedi_sol]

Originally Posted by California98Civic

No extra pedal take up that I have noticed, but I was not paying attention. They're ridiculously easy to install. But even easy is too hard if they're not effective. And I just can't know for certain. Seems logical that they benefit at some level.

so as far as you can tell, the wheels dont seem to turn more "freely" due to less brake drag?

i was thinking of getting a set for my STI to help with coasting.