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Hey all! I got an ls1 04 A4 GTO. LT headers, catless x-pipe through mufflers. Just got a cam swap and tune. Cam is 281 283, .595 .598, 112 lsa. Tuner's idle was set around 850 in P/N which runs great and has good cam lope sound. In gear was the problem. R/D was at 875 which made fighting the car coming to a stop. Too much pull on those stock brakes. I dropped my in gear idle down to 650 and it holds steady in gear. No surging or dying plus it sounds better sitting at a light for instance. Is this a good goal or should I look to have it set lower and add airflow? Drivability feels much better on 650 btw.
 

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Lower? shoot 875 sound low to me. Big cam cars should be around 900-950, your cam is at the line of mild to big cam. I'd think 800 would be the lowest. The stress you put on the engine trying to keep running at the lower RPM is gonna have long term effects. With a 112 LSA and under 600 lift your idle should be smooth. 650 is under stock idle speed and you should be bumping up for a cam. If your brakes won't hold, I'd check those out
 

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Ahh okay. I think my mistake was I didn't really realize how big of a cam it was. This is my DD as well and now I got this huge cam in it. It does feel quite a bit faster up at the higher rpm's but damn it pulls so hard.... If I touch the gas in reverse it'll shoot up to like 20 mph coming out of a parking spot. Do I need a different torque converter? I have an upgraded 4l60e with better internals and a lifetime warranty which came with a different one. Not sure what the difference is......
 

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Needs a converter then raise idle speed back up. The correct torque converter will solve your problems.
 

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Ahh okay. I think my mistake was I didn't really realize how big of a cam it was. This is my DD as well and now I got this huge cam in it. It does feel quite a bit faster up at the higher rpm's but damn it pulls so hard.... If I touch the gas in reverse it'll shoot up to like 20 mph coming out of a parking spot. Do I need a different torque converter? I have an upgraded 4l60e with better internals and a lifetime warranty which came with a different one. Not sure what the difference is......
Yeah, just noticed you're A4. I must have skipped that when I first read, get a torque converter for the cam you got. It will fix your problem and unlock more low-mid end power. High mid and top end will most likely be the same
 

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Lower? shoot 875 sound low to me. Big cam cars should be around 900-950, your cam is at the line of mild to big cam. I'd think 800 would be the lowest. The stress you put on the engine trying to keep running at the lower RPM is gonna have long term effects. With a 112 LSA and under 600 lift your idle should be smooth. 650 is under stock idle speed and you should be bumping up for a cam. If your brakes won't hold, I'd check those out

Under 600 lift on a 112 doesnt mean a smooth idle. the lower the lobe separation angle the more chop all things the same. 650 is too low too though IMO.

Like the other guy said, get a converter in there and you'll be good. At least find put what's in it now since you said its different. A 3600 stall speed would be solid and not too annoying for a DD.
 

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Hey all! I got an ls1 04 A4 GTO. LT headers, catless x-pipe through mufflers. Just got a cam swap and tune. Cam is 281 283, .595 .598, 112 lsa. Tuner's idle was set around 850 in P/N which runs great and has good cam lope sound. In gear was the problem. R/D was at 875 which made fighting the car coming to a stop. Too much pull on those stock brakes. I dropped my in gear idle down to 650 and it holds steady in gear. No surging or dying plus it sounds better sitting at a light for instance. Is this a good goal or should I look to have it set lower and add airflow? Drivability feels much better on 650 btw.
Man no one goes by advertised duration anymore. What’s the duration at .050? Under .600 lift I’m imagining it’s not a very big cam. My cam is 222/233 and I idle mine at 650 rpm. My 228/234 I had idling at 700-720. I notice that lazy or inexperienced tuners will set idle high because they can’t easily get it to idle lower. I have a couple tricks for that. Actually one thing I do, I told a guy about it that has been tuning much longer than me and knows more than I do, he started doing it. What I do is set my base rpm and then manually lower the rpm while logging and dial in the ve as low as I can idle it. Then I go higher than base and dial it in. Then I do the same with the timing to get the strongest idle and highest vacuum and then back the timing a smidge so it can control it.
 

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Rockin the Bakken
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Man no one goes by advertised duration anymore. What’s the duration at .050? Under .600 lift I’m imagining it’s not a very big cam. My cam is 222/233 and I idle mine at 650 rpm. My 228/234 I had idling at 700-720. I notice that lazy or inexperienced tuners will set idle high because they can’t easily get it to idle lower. I have a couple tricks for that. Actually one thing I do, I told a guy about it that has been tuning much longer than me and knows more than I do, he started doing it. What I do is set my base rpm and then manually lower the rpm while logging and dial in the ve as low as I can idle it. Then I go higher than base and dial it in. Then I do the same with the timing to get the strongest idle and highest vacuum and then back the timing a smidge so it can control it.
^^^^I'll be trying this^^^^
 

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Mine idles at 750 with cam and 3200 stall.

Stage III LS6 heads/cam | Cam - [email protected], Lift .568", LSA 114
Fast LSXr 102mm | LPE 100MM MAF | 105MM Accufab TB
3200 Stall

 
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