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I caught this a while back- Comp has a line of "FSL" cams that are CARB-legal, and SUPPOSEDLY no tuning of the stock ECM is required.
It is aimed at the LS3 "family", but West Coast Engines is building a 5.3 crate motor with one of these (210/218, .541/.541, 118 LSA) that does NOT require retuning.
I fail to see how this is possible. Normally ANY cam change should be retuned unless the spec is VERY close to stock. I do realize that retuning voids CARB exemption, so I get that.
BUT how on earth will a 5.3 run with a cam like this without tuning?
Per California law, the only legal cam that can be installed in your vehicle is the one it was emissions rated with. These cams may still pass the exhaust sniff and not throw engine codes, so therefore they won't be obviously illegal by way of having an aftermarket tune
Strange, the summit page claims they are carb approved, so they may be legal by some other means but cam swaps are very frowned upon by Commiefornia
Per California law, the only legal cam that can be installed in your vehicle is the one it was emissions rated with. These cams may still pass the exhaust sniff and not throw engine codes, so therefore they won't be obviously illegal by way of having an aftermarket tune.
Strange, the summit page claims they are carb approved, so they may be legal by some other means, but cam swaps are very frowned upon by Commiefornia
You are correct, BUT Comp went thru the process to get this series exempted by CARB.
I just wonder how it would run even close to normal on a stock tune with this cam so much bigger than the LM7 cam (191/190,.456/.467, 114 LSA)
Tuning gurus, your help is requested....
AND/OR Brian or Joe from Summit....
Dude, I'm so glad I live in Washington, we have no vehicle inspections, no emission testing, no "points on your license", and no vehicle property tax, not to mention no state income tax.
Reading what you guys have to deal with in other states for swaps and inspections just seems absolutely crazy.
Dude, I'm so glad I live in Washington, we have no vehicle inspections, no emission testing, no "points on your license", and no vehicle property tax, not to mention no state income tax.
Reading what you guys have to deal with in other states for swaps and inspections just seems absolutely crazy.
I agree with all the above, PLUS you live in one GORGEOUS state!
Things CAN be done here, but you need to know how to keep it under the radar.
For example, milling and porting heads is unseen and undetectable. A "quiet" enough cam isn't seen or heard. SO FAR, tuning is OK, BUT there is a threat of detecting bitsum "errors" which could tattle on a non-factory tune.
I'm betting it will be Monday IF any of Summit's gurus chime in here.
FWIW -
"CARB Exempt" probably breaks down into more specific detail rather than a catch all. Here's an example from how Vivid Racing's website described the CARB Exemptions for a v6 cam. Would provide link but don't think they are a sponsor.
C.A.R.B. Exempt for Racing and Off-Road Only Vehicles?: Yes, but must be a race/competition only vehicle.
C.A.R.B. Exempt for Federally Certified Vehicles Manufactured Before 1967?: Yes, but must meet tailpipe emission standards for year of vehicle.
C.A.R.B. Exempt for California Certified Vehicles Manufactured Before 1965?: Yes, but must meet tailpipe emission standards for year of vehicle.
C.A.R.B. Exempt for Foreign Vehicles Manufactured Before 1967?: Yes, but must meet tailpipe emission standards for year of vehicle.
FWIW -
"CARB Exempt" probably breaks down into more specific detail rather than a catch all. Here's an example from how Vivid Racing's website described the CARB Exemptions for a v6 cam. Would provide link but don't think they are a sponsor.
C.A.R.B. Exempt for Racing and Off-Road Only Vehicles?: Yes, but must be a race/competition only vehicle.
C.A.R.B. Exempt for Federally Certified Vehicles Manufactured Before 1967?: Yes, but must meet tailpipe emission standards for year of vehicle.
C.A.R.B. Exempt for California Certified Vehicles Manufactured Before 1965?: Yes, but must meet tailpipe emission standards for year of vehicle.
C.A.R.B. Exempt for Foreign Vehicles Manufactured Before 1967?: Yes, but must meet tailpipe emission standards for year of vehicle.
C.A.R.B. Exempt for On-Road Vehicles?: No
I have not seen this and thank you!
Supposedly the Comp cam(s) in question are legal to replace the stock cam in those vehicles OEM with LS engines.
MY main concern is HOW can a 5.3 with this cam run right without a tune?
Yeah, compared to the 60's and 70's the air is much cleaner, and what miniscule amount MIGHT be added by hot rodding is inconsequential. Actually, most of us who keep the cats on and just change to a mild cam are adding nothing to any smog problem.
The whole how we ended up with catalytic converter thing is very frustrating. Also a lot of the environmental risk related to LEADED gasoline which was pretty bad for everyone when used on a large scale.
Los Angeles from 1975, definitely understandable why something had to be done back in the day.
We ended up back in 1975 with the catalytic converters in part because folks didn't keep the carburated cars/trucks with points ignition systems properly tuned up - so they burned dirty. One of the old car magazines maybe CarCraft did an article and showed how a correctly tuned carburator with HEI could pass the sniffer test. Cold start tuning was difficult but do able. However, it would take frequent tune ups to maintain that clean burn. Folks just weren't going to spend the money on frequent clean air tune ups and federal government was smart enough to realize that. So we ended up with that damned 🐈 😻 🐈⬛ 😺 cats. They kept the emissions clean on 1975 & up vehicles pretty consistently.
With a -1 degree overlap cam, with OBD2, an excellent tune, a well maintained Gen III LS1/LS6 can pass the sniffer test without cats 🐈 and easy to maintain, not at all like in the old days. So the air quality isn't damaged by that sort of responsibile rodding. Likewise, keeping the cats the air quality is protected again.
Last edited by 99 Black Bird T/A; Feb 26, 2022 at 07:59 PM.
The thing that infuriates me is that aircraft dump raw fuel in the skies but government is worried about a small amount of vehicle emissions.
Not as a matter of course... only if there is an emergency. They wouldn't waste expensive fuel like that with no reason. Human life >> money or the environment.
Thank you! I suspected that to be true. Notes in the description on Summit's site allude to that.
Plus, these cams are not far from the OEM LS3 cam (204/211,.550/.525,117 LSA), VS the Comp cam (210/218,.570/.541, 118 LSA) spec, so the tune should not be too far out of whack.
That being said, I don't see how West Coast Engines can say it will run in a 5.3L engine originally running an LM7 cam (191/190,.456/.467, 114 LSA) without a tune.
The plot thickens....
This cam is mild and have very wide LSA. It will run fine in LM7 without tune, doesn’t mean it will run optimally.
BUT in my opinion, not worth the effort due to low rpm torque loss.
Without tune and with emission-compliant stock exhaust, LM7 won’t gain that much on top end.
And there is a risk of not passing Cali emissions in LM7.
To play on the safe side, how about ported 706/862 heads, LQ4 cam, numerically-higher gear ratio and slightly higher stall speed?
This cam is mild and have very wide LSA. It will run fine in LM7 without tune, doesn’t mean it will run optimally.
BUT in my opinion, not worth the effort due to low rpm torque loss.
Without tune and with emission-compliant stock exhaust, LM7 won’t gain that much on top end.
And there is a risk of not passing Cali emissions in LM7.
To play on the safe side, how about ported 706/862 heads, LQ4 cam, numerically-higher gear ratio and slightly higher stall speed?
So a wide LSA more or less "keeps" it from needing a tune, though it would be better to do so, obviously.
I would not use that cam myself, but was wondering about the no-tune-needed aspect.
I would not be looking for top end itself, but more low- and mid-range.
I AM thinking of a bowl blend and multiangle valve job.
The early LQ4 cam is the LM7 cam, and the later LQ4 cam is the LQ9 cam, which I am considering a near-clone of (Cam Motion 4.8, Stage 2 truck cam, 198/202,.501/.501,114+2)
OR I'm thinking of the new Summit Torkinator (200/205, .550/.550, 113+4)
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Comp CARB-exempt cams- no tuning "needed"? 
