I live in the People's Republic Of California and I want to do some performance mods on my truck. Now that diesels have to pass a visual inspection, what is actually legal to do?

PS: **** California.

Bump?

Sit and watch it rust? Sorry, I would think one of the tuners that has a CARB number? Do any of them? Good luck maybe someone will chime in.

You can install a Cat-back system exhaust and intake with the C.A.R.B approved sticker on it, there is I believe only one tuner on the market that has a C.A.R.B. number attached to it and it is the Hypertech tuner, the hypertech is not a aggressive tuner by no means and it's suppose to be safe to tow in all three power levels. They have the older style(hypertech programmer III) and then the newer style(hypertech max energy) the difference between the two is that the max energy is internet updatability and it will remove the speed limiter. Both let you change for tire sizes. You can usually pick up used pretty cheap( $150-200) There are other tuners that have there C.A.R.B. approval pending (Banks and Edge products) and those are not legal for use in California accept on a off-road vehicle:cool: If you put gauges (pyro & boost) they should not say anything. There is an article in the latest (June 2010) issue of Diesel power that covers this in detail.

hope this helps,

JLew

You can install a Cat-back system exhaust and intake with the C.A.R.B approved sticker on it, there is I believe only one tuner on the market that has a C.A.R.B. number attached to it and it is the Hypertech tuner, the hypertech is not a aggressive tuner by no means and it's suppose to be safe to tow in all three power levels. They have the older style(hypertech programmer III) and then the newer style(hypertech max energy) the difference between the two is that the max energy is internet updatability and it will remove the speed limiter. Both let you change for tire sizes. You can usually pick up used pretty cheap( $150-200) There are other tuners that have there C.A.R.B. approval pending (Banks and Edge products) and those are not legal for use in California accept on a off-road vehicle:cool: If you put gauges (pyro & boost) they should not say anything. There is an article in the latest (June 2010) issue of Diesel power that covers this in detail.

hope this helps,

JLew

That's actually really helpful. Thanks.

I'm keeping the original cats for now, but putting dual straight-pipes on in the next month or two. I had an actual exhaust shop tell me what was legal in that regard. It's more the programmers and intakes that I was worried about. I don't want anything crazy, but I'd like to get my truck in the low-to-mid 400s when it comes to horsepower, and I don't see how I can do that without engine modifications.

http://www.hypertech.com/products-results.aspx
Re: CARB http://www.hypertech.com/fuel-economy.aspx

That's actually really helpful. Thanks.

I'm keeping the original cats for now, but putting dual straight-pipes on in the next month or two. I had an actual exhaust shop tell me what was legal in that regard. It's more the programmers and intakes that I was worried about. I don't want anything crazy, but I'd like to get my truck in the low-to-mid 400s when it comes to horsepower, and I don't see how I can do that without engine modifications.


The Duramax engine feeds both exhaust manifold into the turbo and then out of one downpipe going into the catalytic converter. You CAN go straight pipe (no muffler) but you won't be able to run 2 straight pipes from the motor all the way back...and also, they WILL crawl under to look for a CAT! I know because I had a smog check done when I purchased my truck this past February.If what you want is to have two tail pipes exiting the rear of the truck you would put a y-bridge right before the rear axle that is how the exhaust companies sell their dual-exhaust kits.

JLew

P.S. A aftermarket intake is not going to really help you at those hp levels until you reach 500+ hp I would keep the stock filter, it beter filtering anyways, and just use the tuner on the hypertech on the 90hp setting. that and a exhaust system would get you close to where you want to be...Also, get some gauges, EGT (pyrometer) and boost to monitor the exhaust gas temps.

I have had good luck towing with my Hypertech on level three. Taking a trip with a trailer to upstate NY in two weeks, love my Duramax!

You can do pretty much any mods you want...just be prepared to put it back to stock for the inspection.

I have yet to see a CARB EO number for any programmer/tuner for a diesel truck. I have seen several people claim they are CARB complient but none of these companies can provide an EO number. I suggest contacting any of the tuning companies that you are interested in and finding out if they have an EO number. If they do not have an EO number for the product you are supposed to fail. If you set the truck back to stock and remove the tuner they cannot tell.

The Duramax engine feeds both exhaust manifold into the turbo and then out of one downpipe going into the catalytic converter. You CAN go straight pipe (no muffler) but you won't be able to run 2 straight pipes from the motor all the way back...and also, they WILL crawl under to look for a CAT! I know because I had a smog check done when I purchased my truck this past February.If what you want is to have two tail pipes exiting the rear of the truck you would put a y-bridge right before the rear axle that is how the exhaust companies sell their dual-exhaust kits.

That's actually what I meant by dual straight pipes. Probably a bad choice of wording on my part.

P.S. A aftermarket intake is not going to really help you at those hp levels until you reach 500+ hp I would keep the stock filter, it beter filtering anyways, and just use the tuner on the hypertech on the 90hp setting. that and a exhaust system would get you close to where you want to be...Also, get some gauges, EGT (pyrometer) and boost to monitor the exhaust gas temps.

Sounds good. Thanks. :cool: