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Discussion Starter · #1 ·
In June I purchased a 2011 Elise R with a BOE 300. We may have tracked down the cause of the raw gas smell on full acceleration: we need to replace the fuel injector spacers with the correct ones. The charcoal cannister appears to be intact, and the mounts are new style and unbroken.

The car also back fires when you let up on the gas at high revs, and BOE said that this could be due to a cat delete. It appears that my car has had the cat deleted.

I imagine that cats are deleted to improve exhaust flow and to reduce weight. What is the down side to putting a cat back in place? And are there people out there who have performed a cat delete and have spare used cats that they would part with?

I welcome all comments (I think)

Jon
 

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It might depend which box was checked at the time the REV300 tune was ordered. It could be ordered with or without cat. Are your exhaust headers stock? What muffler are you running? Are you logging any codes with obd? You might want to place a WTB in the Marketplace
 

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2006 Lotus Elise, British Racing Green
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I think deleting a cat would have more of an effect for track driving, since I think that's normally when your cat would get blown out and there is a benefit to not having one. From a street use perspective I think a sport cat is fine and that you aren't reducing that much power by having a decent sport cat. It also makes the car smell less bad haha.
 

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Raw gas smell is easily just the result of being cat-less. Part of what a cat does is convert unburned hydrocarbons to water and c02.

BOE did a study (somewhere on their site) where they found no meaningful difference in the different cats they tested. However, heavy track use can burn out a cat, but for street use decats are more for sound and fire. Which are perfectly valid reasons, haha
 

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The Blue Meanie - 2006 Polar Blue Elise & Bernice - 2010 Chilli Red Mini Cooper S
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As others have said, the cat wont last on track.

Without it, it shoots nice little fire balls though ;)
Rev400 w/ boe tune (no cat)

Thanks for the vid dude! That's sick! I just traded some CF side scoops for a cat delete pipe. Can't wait to be spittin fire!
 

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Discussion Starter · #9 ·
It might depend which box was checked at the time the REV300 tune was ordered. It could be ordered with or without cat. Are your exhaust headers stock? What muffler are you running? Are you logging any codes with obd? You might want to place a WTB in the Marketplace
The original car description says "2bular Exhaust". I know nothing about the headers: how would I tell? The CEL is not on and there are no stored codes.
 

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Well it's a plus you have no codes! You could post a photo of the 2tublar muffler and maybe members could ID which one it is. In the photo below is what the oem headers look like and if that exhaust shield is over it it's bound to be oem. Not sure if it's variations in tunes but I don't get backfiring at all while others do. To me it sounds like overly rich and the fuel's accumulating and then igniting.

Bicycle part Wood Automotive exhaust Auto part Muffler
 

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Thanks for the vid dude! That's sick! I just traded some CF side scoops for a cat delete pipe. Can't wait to be spittin fire!

Not sure how much a stock car will shoot them or not. The BOE tune runs on the richer side which will leave more unburnt fuel on lifting throttle (I am assuming).

I have a buddy with his own exhaust design (basically a straight-pipe) on otherwise stock car. I have seen him shoot a flame or two, but not as much as my car. He really winds up to the upper RPM (I dont push the upper RPMs with the boosted motor and never hit the rev limiter). I do know if you drive the stock version hard enough with headers and no cat a flame will pop every now and again. But you would have to be driving the car pretty hard.

I think the tune and increased fuel flow have a lot to do with the additional flames
 

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Discussion Starter · #12 ·
Well it's a plus you have no codes! You could post a photo of the 2tublar muffler and maybe members could ID which one it is. In the photo below is what the oem headers look like and if that exhaust shield is over it it's bound to be oem. Not sure if it's variations in tunes but I don't get backfiring at all while others do. To me it sounds like overly rich and the fuel's accumulating and then igniting.
I don't see any way of taking meaningful pictures of the exhaust without getting the car up on a lift. I will do that, but it will take a few weeks to arrange that. Thanks!
 

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I don't see any way of taking meaningful pictures of the exhaust without getting the car up on a lift. I will do that, but it will take a few weeks to arrange that. Thanks!
Look between valve cover and clam if you see that shield you have oem. You need to look down not up.
 
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I’d say your gas smell is coming from the no cat, I’m sc’d and running the mwr decat pipe… not sure if it actually added any power but it definitely feels less restricted and ofcourse it shoots flames
Tire Wheel Car Vehicle Cloud
 

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If you look at the welds of the pipe connecting to the header, it sure looks like the oem cat. I suggested that John take a closer look to see if there is heat shielding around the u bend as this doesn't look like an aftermarket pipe. I'm guessing that either the cat is bad or his car is just running super rich/some other problem. Maybe the previous owner had a lead foot and fried the honeycomb. Any thoughts why he has raw fuel smell other than blown cat?
 

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You should be able to contact BOE and with the VIN find what boxes were checked for the REV300 tune. They do ask if you use cat or not and tune accordingly. If they tuned for one and yours is damaged that might explain the backfiring?
 
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