LS3 F35 cam Issues
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LS3 F35 cam Issues
I have a 13 C6 that is a full build of Heads, Cam, Intake. The heads are Gwatney 281cc ported, the intake is the Gwatney Rod-mod ported ls3 manifold, and the cam of course is the Texas Speed F35 Stage 4 Camshaft. It has a random misfire/breakup at 1700-2100rpm when over 75% throttle. It is only at this rpm. I have changed the coils, plugs, wires, crank sensor, MAF, and map sensor trying to find out what the issue is. My AFR gauge is reading a great 13.9-14.1 afr’d during the breakup with no change. Can ANYONE HELP please with this situation? Is it simply because the cam is to big? I have had 3 dyno tuners tell me all the same exact thing.
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From: Cape Coral, Florida
Best to take your car to a diagnostic shop where they can put a scope and scan tool on it and see what’s going on !!…I see you already fired the parts canon with no success !!..what part of the country are you located ??
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It has been to 4 shops and everyone keeps saying the Cam, it’s just a bit odd to me is all. I was curious if anyone else has been through the same thing. The car doesn’t throw any lights or anything like that so there’s nothing to diagnose as far as that goes. I am in NC also.
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Race Director
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Safety Car
Joined: Sep 2007
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From: South Florida
Out of curoisity did you drive any big cammed cars before deciding on the F35? It's a pretty big cam, if 3-4 shops are all saying the same thing.... you're probably gonna have to live with it unless you wanna keep throwing more and more money to tuners. Big cams come with quirks, some worse than others.
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Burning Brakes
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From: Raeford NC
tossing a random misfire code? or has a noticeable miss that you can hear/feel
Where in NC are you I'm in the Fort Bragg area and tune a lot of stuff I can check it out if you're localish. Or recommend someone who can.
Where in NC are you I'm in the Fort Bragg area and tune a lot of stuff I can check it out if you're localish. Or recommend someone who can.
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Out of curoisity did you drive any big cammed cars before deciding on the F35? It's a pretty big cam, if 3-4 shops are all saying the same thing.... you're probably gonna have to live with it unless you wanna keep throwing more and more money to tuners. Big cams come with quirks, some worse than others.
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I am from Statesville-Mooresville area, it’s not throwing any misfire codes due to the cam being so large it’s impossible to use this data. It 100% is very noticeable, as in you can audibly hear it and it will physically feel like a breakup/misfire. Again only at 75-100% throttle from 1700-2100 rpm. I really think it is a turbulence issue possibly. I had to remove the accordion style throttle body couple and install a smooth boot in its place so I’m curious if this may have caused some turbulence. Very strange issue that no tuner has yet to be able to answer. All tuners have been big tunes for NC and all say the same thing about the cam. We just recently noticed the MAF data is quite wild at the time of it happening and I can’t help but wonder if this is possibly a issue. During the stutter/breakup the car is keeping good AFR’s so it’s very conflicting.
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Burning Brakes
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From: Raeford NC
all MSD? Msd wires are what I had issues with on both a CTSV and C6. Put OEM on and never had an issue again with the CTSV a few years later I got my corvette and it came with MSD wires, and it was the same thing. I kept having issues so I put new OEM wires on and they were fine, ended up switching to firecore also were fine. I'm just tossing out issues I've had over the years. Without the car in person, it's impossible to troubleshoot.
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all MSD? Msd wires are what I had issues with on both a CTSV and C6. Put OEM on and never had an issue again with the CTSV a few years later I got my corvette and it came with MSD wires, and it was the same thing. I kept having issues so I put new OEM wires on and they were fine, ended up switching to firecore also were fine. I'm just tossing out issues I've had over the years. Without the car in person, it's impossible to troubleshoot.
Burning Brakes
Joined: Apr 2016
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From: Raeford NC
Let us know how it goes. I have a vararam on my car and it's had 4 cams now. I've also tuned a few vararam f35 cars. What lifters and pushrods did you get? Heads milled at all? Checked the rockers?
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I’m running Johnson 2117R lifters and 7.425 chromoly Texas speed pushrods. CHE Bronze Trunion as well and rockers are solid. The heads are not milled, they are 281CC Gwatney heads, Gwatney ported-Rod mod ls3 intake manifold. (Tons more) but all of that is the most relatable to the subject.
Safety Car
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From: South Florida
I’m running Johnson 2117R lifters and 7.425 chromoly Texas speed pushrods. CHE Bronze Trunion as well and rockers are solid. The heads are not milled, they are 281CC Gwatney heads, Gwatney ported-Rod mod ls3 intake manifold. (Tons more) but all of that is the most relatable to the subject.