A4 Cam-only LS1 at a crossroads
08-16-2019, 05:16 PM
#21
I ran my stock 4l60e with no issues. Yank 3600 stall. Just kept the torque management in the tune. If you plan to rev it above 6-6200, you'll want to get something built. stock 4l60e's don't like RPM. It'll handle the power as its very linear with the centrifugal blower. Glad you're considering this. It'll make way more power than changing cams or adding heads, no bottles to fill, and gives you room to grow in the future. Get a set of Siemens 60lb high impedance injectors, a Walbro 450, and a hot wire kit for the pump and you have a fuel system good to 600whp+ for cheap.
Leave everything alone and add a blower. Your cam and stall will both work with a supercharger, and no need to tear out the motor or swap cams and replace heads. You don't need to cut/hack anything to add a centrifugal supercharger like a P1SC or D1SC. They show up used in the for sale section pretty often and will more than meet your goals without affecting driveability.
I agree with all this. I have 650+ RWHP and my 4L60 (built) is holding. I have some torque management dialed in. I have a turbo which ramps up softly. If you go nitrous, its going to be much harder on parts.
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TransAmWS.6 (08-16-2019)
08-16-2019, 11:37 PM
#22
TECH Fanatic
Thread Starter
I went with a front mount as they are more efficient and handle more power than the twins, but for your goals the twins would be fine. You can choose to mount the FMIC or twin coolers multiple different ways as there's plenty of dead space up front in an F car, mostly cause they shoved the motor halfway under the cowl lol. You just pick a size cooler for your intended install area and power goals.
As far as the trans stuff, I have no doubt that had I turned 6800-7000 I probably would have picked up half a second as it was set to shift at ~6100. But to me, saving thousands of dollars and not having any downtime of swapping transmissions was worth half a second to me. It was just a fun car to run around on the street that drove very nicely and would run a low 11 at the track at low boost without an issue. If you were shifting at the same RPM and just talk about torque limiting vs. none, other people have said it was really only worth a couple tenths at best. Again, not worth turning it off to me for that little of a gain. If I'm going to do a mod, I don't care about a couple tenths, I want to drop a second or more on a change LOL. That's why I suggested boost instead of swapping a cam or adding heads.
As far as the trans stuff, I have no doubt that had I turned 6800-7000 I probably would have picked up half a second as it was set to shift at ~6100. But to me, saving thousands of dollars and not having any downtime of swapping transmissions was worth half a second to me. It was just a fun car to run around on the street that drove very nicely and would run a low 11 at the track at low boost without an issue. If you were shifting at the same RPM and just talk about torque limiting vs. none, other people have said it was really only worth a couple tenths at best. Again, not worth turning it off to me for that little of a gain. If I'm going to do a mod, I don't care about a couple tenths, I want to drop a second or more on a change LOL. That's why I suggested boost instead of swapping a cam or adding heads.
I agree...FI is what I would do. Just get the P1x with twin high flow so you don't have to cut anything.
What will kill the stock trans is skip shifting from 4th(I always manually down shifted mine into the gear I wanted to pull from) or WOT shift into 4th. So I would set the trans up to shift 6800 1st and 2nd, (you are not at that rpm long enough to create a ton of heat)and don't run it in 4th. You should be able to run a gear that will allow 140+ mph in 3rd any way.
What will kill the stock trans is skip shifting from 4th(I always manually down shifted mine into the gear I wanted to pull from) or WOT shift into 4th. So I would set the trans up to shift 6800 1st and 2nd, (you are not at that rpm long enough to create a ton of heat)and don't run it in 4th. You should be able to run a gear that will allow 140+ mph in 3rd any way.
08-18-2019, 11:37 AM
#23
I agree...FI is what I would do. Just get the P1x with twin high flow so you don't have to cut anything.
What will kill the stock trans is skip shifting from 4th(I always manually down shifted mine into the gear I wanted to pull from) or WOT shift into 4th. So I would set the trans up to shift 6800 1st and 2nd, (you are not at that rpm long enough to create a ton of heat)and don't run it in 4th. You should be able to run a gear that will allow 140+ mph in 3rd any way.
What will kill the stock trans is skip shifting from 4th(I always manually down shifted mine into the gear I wanted to pull from) or WOT shift into 4th. So I would set the trans up to shift 6800 1st and 2nd, (you are not at that rpm long enough to create a ton of heat)and don't run it in 4th. You should be able to run a gear that will allow 140+ mph in 3rd any way.
Can you elaborate on this? Are you saying it's bad to keep it in drive (4th) and let the trans downshift, rather than select 3 to make it down shift?
08-18-2019, 01:53 PM
#24
Basically you are cruising along in overdrive. Or third. And you punch it to the floor, it drops to second or first by itself. Yea. The trans just basically when from loaded, to unloaded (almost like neutral) and back loaded. Bad. Very bad. It’s almost like revving the engine and dropping into gear. That shock will tear the trans up in short order on a modded car. If you need to go to second, pull it to third, let rpm catch up, then pull to second, let rpm catch up then give it some pedal to hold at steady speed, then punch it or roll into it quickly. Remember, any unnecessary shock you give it, weakens it little by little. It works fine on a stock vehicle because you aren’t making as much power and all the tq management helps prolong things. Take the tq management out and start modding......you’ll start breaking ****.
AND WHATEVER YOU DO......NEVER, EVER run a 4l60e in overdrive at full throttle if you are making decent power. You’ll smoke the clutches quick. I don’t care if it’s built. I will not ever run overdrive hard. If I cant get it done in third, I change rear end ratio.
