Felix C

Come on folks. Let it be. This was a damned good thread.

Not everyone wants to install gears. There is plenty of gear multiplication with a 3.42 rear and a M6.

Question is regarding the camshaft in question,-the one making 400/400--is it a fluke?

gojo

iTrader: (12)

https://ls1tech.com/forums/dynamometer-results-comparisons/238188-new-heads.html

Go here for an honest dyno graph. Terrific cam and it's for sale.

https://ls1tech.com/forums/lsx-parts-sale/364476-c5-parts-sale.html

Ragtop 99

iTrader: (7)

With an A4, you'll never be at WOT below the stall speed. Therefore torque below 3500 is not much of an issue.

Based upon your sig, it looks like you have stock manifolds and cats; so you need more help on the exhaust side and don't want a ton of overlap. Therefore, I like your last choice. I'd look at 220/228 115 +3 as another alternative.

JL ws-6

iTrader: (50)

You're 3rd cam choice is similar to the one that Eastside did for me.. you may wanan call them, I'm pretty sure that they have a couple in stock. Tell them Jason sent you... and you're looking for the cam that's in my car. You won't be dissappointed.

nuzee

iTrader: (2)

You know, I was a firm believer in that thought. But from my recent track testing of a newly installed TCI3500 stall, I'm changing my mind a little bit. I am able to pull 1.61-1.63 60 fts and lift a front wheel. I'm thinking that at least part of the 60 ft improvement is due to my "stump-puller" cam.

Based on some info I logged during runs, there is a small portion of time when the car hasn't moved yet and the engine is flashing to stall speed (~3600-3700) that stump-pulling torque is shifting the car's weight from front to back quickly> which aids traction> which lowers 60 ft> yada yada yada. I don't know if this is a fact or not, its just one of my thoughts. BTW, I seem to get better 60s by flash stalling rather than stalling it up.

Ragtop 99

iTrader: (7)

Nuzee:

I agree that as that there is a brief instance when the car is just starting to roll when you are simultaneously releasing the brake and pressing the gas and the converter is flashing up from the brake-stall to the converter's stall. However, I don't know if you are actually at WOT since the TB is going from about 10% open to 100% and the manifold is filling during this instant in time. If you ever dyno an M6 and starting recording before going to WOT, you'll see that it takes a couple hundred rpm for the power to jump all the way up. The cam helps breathing during that instant in time, I'm just not sure by how much. In any event a cam that makes torque at 3500 will make ok torque at 3000 and be enough for that instant before full stall is reached.

In his case, I was just trying to point out that on the street, low end grunt does not exist with a an aftermarket stall. It's just about impossible to find yourself at more than 50% TPS and be at less than 3000 rpm. The stock A4 tables will call for a downshift and/or unlock the converter under those conditions.

DAPSUPRSLO

iTrader: (14)

This was my car and it was a m6, no auto here or stalls to skew results.

DAPSUPRSLO

iTrader: (14)

Twas on stock heads, albeit 01 ls1 heads.

Felix C

I know, well I know now. I did not know then.

Spinmonster

Going to 3.73's will net quicker 1/4 times than any of the cams shown without headwork. It will pull harder in all gears.

It will also set the stage later for you to go to a real cam while maintaining driveability by getting you into your power band faster.

Every car I have has maximized gearing and that includes a 68 dart with 6.13 gears that pulls a freekin wheelie for a ridiculous distance down the 1/4. Build your car from the back to the front. Don't take advice from peple with near 12 second 1/4 times. Getting a bigger cam never loses TQ it just moves it higher in the power band and gearing puts you in that power band faster. Looking at a dyno sheet and saying well this cam has more TQ at 2000 rpm doesnt mean you lost or gained TQ with a cam change. You simply need gearing to put you at the RPM faster where the greater TQ is made.

DAPSUPRSLO

iTrader: (14)

Absolutely, and being able to hold the gear out longer (hold first out longer, hold second out longer, etc. etc.) will always amount up to an advantage in the quarter unless your friction losses through the transmission, rear, etc. are sky high.

blkZ28spt

Do you realize that steeper gears mean you will spend LESS time in each gear?

Ragtop 99

iTrader: (7)

Before you make that generalization to all A4's, you need to know what stall he has. It has been documented many times over, that if you have a bolt-on car with a 3500 or higher stall and switch from the factory 3.23s to 3.73s, the most you gain is .1 and 1 mph. Going to 4.10s adds another .05 improvement. The gain on the switch from 2.73s is a little better, but not as dramatic as you would expect.

You are correct about the gears if you have a stock stall. The switch to 3.73s are good for .2. - .3 depending upon which gear you switch from. However, if he has a stock stall, cam, and gears then a torque converter should be his first mod as that will net .5 or more. Then he can move on to a cam or gears.

Even with a mild cam like what he is considering, he will see at least .2 and 2 mph gain.

I agree that the extra gearing works to your advantage by winding out the cam, but for an A4 it is the torque converter that makes the big difference. I also agree that gears can help the drivability in town of a modified car.

DAPSUPRSLO

iTrader: (14)

Yes, but you are also multiplying your power to a greater extent too by having more gear and a higher rpm band.

Firehawk526

iTrader: (1)

How'd I miss this thread, I'll never know, but took me 10 minutes to review the content.......and basically, I am seeking the same 226-230 range cam set-up w/62--6400 rpm range, with my M6 I don't need anymore torque. I need power in the higher RPM range. Once I install the 4.10/9" w/locker, I shouldn't have a torque/launching issue I wouldn't think.

Question: Should you always strive for a balance between hp and tq (proportional ratio)?

DYNO'd 334 rwhlhp 389 enghp
353 rwhltq 403 engtq

When I run, it seems I don't have the ooomph down the strip!

I do have a 224/224 .050 lift 110 lobe sep/106 intake centerline READY for install, but I thought it may be the wrong cam for my application. Several ppl have told me that it would serve an A4 w/stall very well, but not for an M6

SauronWS6

What's the lift?

Firehawk526

iTrader: (1)

Dap.....you wanna answer that Q? Ironically, it's DapSuperslo's cam!

A couple of non-EFA locals said the centerline should be more like 112-114 for my application, but as I indicated earlier I have much learning to do before the decision is made.......want to keep the car w/good street manners, but have the powerband when required.

DAPSUPRSLO

iTrader: (14)

The lift is .568". One way to help the cam up top would be to add 1.8 rockers and or install and adjustable timing chain for retarding the cam.


BTW, I am SUPRSLO and DAPSUPRSLO. My stuff is messed up.

Firehawk526

iTrader: (1)

Don't wanna really change the rocker set-up. Just a quick swap out of pulley (ASP), 918 springs, titanium retainers, and 7.4 pushrods. This will do me until the engine wears out, and then we'll be STROKIN' w/ diff head combo.

I am not gonna sweat 10hp if it means losing 1-2 mpg.

Firehawk526

iTrader: (1)

OK, Hero.....fix dat name!