heya guys

i just wondering everytime i WOT the car, i keep getting this black crap on my rear bumper but it wiped off easily

is it from running to rich or oil ??

is it right that new built engine will normally burns oil for a while ??

thanks

 

i never burned oil with me new built engine...

and typically it could be either fuel or oil... ive seen more fuel though then oil

 

oh ok

additional info : im running straight thru exhaust with no cat, if that helps

 

Get used to it...My car is NA and half of my bumper is black..Its the price you pay for not having a cat/having a modified exhaust/being turbo charged.Turbo motors use a LOT more fuel at WOT hence the carbon on your bumper.

 

so its normal , i aint have to be worry ???

 

No need to worry. As long as you check your oil and its not using it at an accelerated rate, then no problems.Its just fuel.

 

i do burn some oil

i remember before i drop the car to get tuned, i had the oil level between the 2 holes on the dipstick

when i picked it up it was almost empty that vtec didnt even kick in, i top up about a litre of oil to get to the FULL mark

car probably did about 20-25 pulls on the dyno tho, is that normal to burn that much oil ??

 

Not really...Have you dont a compression test? Is the motor stock(internals)? Does it smoke blue or white excessively or does it smoke a little at start up after its been sitting over night?

 

yeah compression is 190-200psi

when i start it in the morning it just blows steam, no black or blue smoke at all

altho i could see a greyish colour smoke when im at WOT from the rear view mirror

other than that motor is going very strong, it makes 355whp on 13psi

 

I wouldnt worry then...How many miles(or km's) are on your motor? dohc vtecs will use a little oil anyways, especially when turbod.

 

On a properly tuned car there shouldn't be that much soot on the bumper. I can see a little bit for high powered setups, but not on a mild setup. At about 450whp my bumper would get darkened when I was running real right, about 10:1 but one I retuned it to 11-11.5:1 hardly any would end up on my bumper. Get it tuned.

And greyish colour smoke can be anythnig from too much fuel to slight oil to slight head gasket issues.

 

Or it can be really black if you havnt washed your car in 3 months and drive 200 miles a week like me

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tchleung &raquo;</TD></TR><TR><TD CLASS="quote">On a properly tuned car there shouldn't be that much soot on the bumper. I can see a little bit for high powered setups, but not on a mild setup. At about 450whp my bumper would get darkened when I was running real right, about 10:1 but one I retuned it to 11-11.5:1 hardly any would end up on my bumper. Get it tuned.

And greyish colour smoke can be anythnig from too much fuel to slight oil to slight head gasket issues.</TD></TR></TABLE>

if i have a slight headgasket problem , wouldnt i be losing water ???

im not losing water at all

 

boink

 

Wax the **** outta that bumper...and keep up with it from time to time..so u dont ruin ur clear..!

 

im not asking how to clean it

i just wanna know if i should be worrying cuz i keep getting this black soot all over my rear bumper

 

its just the soothe and crap from not having a cat...depending how ur muffler is put on and how close it is to the bumper...u can usally do pretty good...if the tip is out past the bumper a lil..

 

I get it too and my a/f was around 11.8. I also use a chambered muffler so I think the crap collects in there and when you really get on it it blows out all over the place.

 

Agreed... also, lean it out a bit... just not too much

 

ok sounds like its a pretty common thing to happen on honda cars, i can stop worrying now then

thankie

 

Do you know if the tuner has it running closed loop? If its closed-loop (not correcting AFR when cruising) then you're probably running rich constatly. That extra 10% fuel isn't being burnt properly, and that's the **** that sticks to your bumper.

Its not the worst thing in the world, I consider bumper soot more of a turbo right-of-passage thing more than anything.