A4 & LS6 Power - Timebomb?
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Joined: Oct 2000
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From: Monticello MN
Originally Posted by pettrix
Can a stock 2004 A4 with stock converter handle the power of a LS6 (405HP) engine with headers? Or is it a timebomb waiting to go off? 
Ed
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I have heard that over 400RWHP and you have to start worrying about the staock transmission. But that information was no doubt anecdotal.
In any event, with 405bhp you should not have to worry too much. I should hope not. 405bhp considering 20% drive line loss for the A4 comes to 324 rwhp. Check my signature.
In any event, with 405bhp you should not have to worry too much. I should hope not. 405bhp considering 20% drive line loss for the A4 comes to 324 rwhp. Check my signature.
Last edited by '06 Quicksilver Z06; Sep 18, 2004 at 06:58 PM.
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A4 driveline loss is much less than 20%. Buried in a thread somewhere a member asked a Corvette engineer what the losses were. He said about 13 for the MN6 and 16 for the A4. A difference of 4% may not seem like much but its 4% free HP without doing any mods. 20% is from the old days when drive trains were inefficient.
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From: Monticello MN
Originally Posted by jim2527
A4 driveline loss is much less than 20%. Buried in a thread somewhere a member asked a Corvette engineer what the losses were. He said about 13 for the MN6 and 16 for the A4. A difference of 4% may not seem like much but its 4% free HP without doing any mods. 20% is from the old days when drive trains were inefficient.
Ed
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From: Monticello MN
Originally Posted by donscheffler
I have mine dynoed on Friday.
405BHP and 330RWHP. That is about 19%!
405BHP and 330RWHP. That is about 19%!
Ed
Last edited by C5XTASY; Sep 19, 2004 at 10:51 AM.
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From: Monticello MN
Originally Posted by donscheffler
You edited your message.
Really just have these mods.
Really just have these mods.
Ed
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From: The Arid Sunny Desert
Originally Posted by jim2527
A4 driveline loss is much less than 20%. Buried in a thread somewhere a member asked a Corvette engineer what the losses were. He said about 13 for the MN6 and 16 for the A4. A difference of 4% may not seem like much but its 4% free HP without doing any mods. 20% is from the old days when drive trains were inefficient.
Not too sure about that, in my case anyway. My vert was dynoed @ 279 RWHP before modding. I'm at 400 RWHP now on the stock A4 and hope it lasts a while. I have been doing tranny fluid changes 2x/year and replacing the fluid with Redline Synthetic. So far so good.
Last edited by Laguna Blu; Sep 19, 2004 at 08:06 PM.
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Originally Posted by C5XTASY
Interesting and, I believe, true. A friend had his 2003 A4 dyno tested prior to some mods and came up with 297 rwhp. Looking at a factory flywheel rating of 350 hp, that works out to a driveline loss of 15.14%. The dyno numbers of many 6 speeds on the Forum have been around 310, or so. That works out to about 11.4%. Pretty close.
Ed
Ed
Most of the stock A4s I have seen here dyno in the 280- low 290 range.
Most of the MN6s I have seen here are described in the low 290-low 300 range, bone stock.
Last edited by '06 Quicksilver Z06; Sep 19, 2004 at 08:08 PM.
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From: Monticello MN
Originally Posted by EB20003
Really? My A4, when it was basically stock, except for a Z06 airlid, dynoed at 282.6 RWHP. Looking at a factory flywheel rating of 350 hp, that works out to a driveline loss of 19.26%.
Most of the stock A4s I have seen here dyno in the 280- low 290 range.
Most of the MN6s I have seen here are described in the low 290-low 300 range, bone stock.
Most of the stock A4s I have seen here dyno in the 280- low 290 range.
Most of the MN6s I have seen here are described in the low 290-low 300 range, bone stock.
Ed
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And actually, there's not a damn thing anyone can do about driveline losses other than changing the type of transmission he uses.
What about lighter wheels and tires? How about higher (lower number, say 2.73) gears?
Most who know will tell you that going to lower gears (higher number) typically will result in lower dyno numbers with no changes in BHP. For example changing nothing else but going to say 3.90 gears from 2.73s can result in lower dyno nbrs.
If your friends A4 Anniversary edition dynoed at 297 rwhp, another explanation, among many possibilities for this high number, could be that his engine actually was underrated at 350 bhp. This has been known to happen on numerous occasions with various engines. The LS6 in the Z06 comes to mind. Many Zs are said to be underrated as are SVT Cobras..
In my case 1-.1926= .8074 282.6/.8074= 350
297/.8074= 367 bhp or 17hp above the rated 350.
I suspect the real answer will vary among cars.
Last edited by '06 Quicksilver Z06; Sep 19, 2004 at 10:28 PM.
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From: Monticello MN
Originally Posted by EB20003
What about lighter wheels and tires? How about higher (lower number, say 2.73) gears?
Most who know will tell you that going to lower gears (higher number) typically will result in lower dyno numbers with no changes in BHP. For example changing nothing else but going to say 3.90 gears from 2.73s can result in lower dyno nbrs.
If your friends A4 Anniversary edition dynoed at 297 rwhp, another explanation, among many possibilities for this high number, could be that his engine actually was underrated at 350 bhp. This has been known to happen on numerous occasions with various engines. The LS6 in the Z06 comes to mind. Many Zs are said to be underrated as are SVT Cobras..
In my case 1-.1926= .8074 282.6/.8074= 350
297/.8074= 367 bhp or 17hp above the rated 350.
I suspect the real answer will vary among cars.
Most who know will tell you that going to lower gears (higher number) typically will result in lower dyno numbers with no changes in BHP. For example changing nothing else but going to say 3.90 gears from 2.73s can result in lower dyno nbrs.
If your friends A4 Anniversary edition dynoed at 297 rwhp, another explanation, among many possibilities for this high number, could be that his engine actually was underrated at 350 bhp. This has been known to happen on numerous occasions with various engines. The LS6 in the Z06 comes to mind. Many Zs are said to be underrated as are SVT Cobras..
In my case 1-.1926= .8074 282.6/.8074= 350
297/.8074= 367 bhp or 17hp above the rated 350.
I suspect the real answer will vary among cars.
Ed
