Auto guys check this out!!!!!!!

[MaxedGT]

For the 06 season, I did the J-mod and installed a BBK x-pipe, and ran a 13.49 @ 102.99 mph. ran several 13.5's that year and was very happy with the car. But somewhere along the line I lost about 10 hp and had trouble running even a 13.6.
I found the problem after more than two years. This might be hard to believe. I lowered the shift pressures back to stock and ran three low 13.5's at close to 103 mph. If I had emptied the trunk and removed the spare and jack, and pumped my front tire pressures up, I may have ran a new best.
My theory behind it. Upping the shift pressures causes the front pump to work harder, thus the engine is put under more load driving the pump. sort of like holding your steering hard at the end of the lock causes the power steering pump to put a load on the engine.
Try lowering your shift pressures and see if you get the same results. Then post here. I'm thinking this is new info that no-one has given any thought to. Kinda of a breakthrough?

 

[CobraRed_96_GT]

Interesting read. I also think it has to do with how your trans is set-up. With the stock set-up the trans doesn't have the ability to sustain line pressure, more like surges that it builds up before a shift in the schedule then it diminishes in order to reduce wear/heat and make for smoother shifts (for old people). While the j-mod serves to calibrate the application of this line pressure - i'm not sure it alone changes the method of the trans enough to operate any differently. So maybe the pump having to work so often has to do with question.
This is one of the reasons i chose to use a Stage II shift kit and use the j-mod procedure on a new valve body and for it's accumulator piston replacement suggestions - as the kit serves to sustain that pressure - even with manual shifts where line pressure on the stock trans is severely low.
Whatever the case, this is quite relevant to me as I'm soon to be to changing the shift schedule/rev limit, and adjust the line pressure on my trans.

 

[justinschmidt1]

Never heard that....I might try it and see what happens...but I dont see how that would have any affect.

 

[MaxedGT]

I'd never heard of it before either. That's why I think it's important info. When I first did the J-mod and x-pipe, I left all the transmission settings stock to see the results. Somewhere along the line I upped the shift pressures hoping to improve my times even further. I like the way the tranny shifts better with the higher pressures. But I never ran as quick any longer. I thought it was the weather conditions. But after still running slower the next season I started looking for a problem. I flushed the injectors, changed my fuel filter. checked fuel pressure. even removed the exhaust looking for a restriction, cause I thought the exhaust was quiter, and on and on. I finally thought about lowering the shift pressures after there was nothing else I could think of. I even switched to a Predator tuner, replacing my Superchips tuner. So this last friday, I lowered the pressures back to stock, first run was a [email protected], then [email protected], then I blew my launch and spun through first, [email protected] (trap speed still there), and [email protected]. The previous time out, ran all 13.7's +or Minus .02 seconds, in four runs @ about 101 mph. I threw the time slips away. With the pressures up, I'd bark the drag radials on the 2-3 shift, but not with the stock pressures. I was getting really pissed off trying to find that lost power. Now I'm stoked!

 

[CobraRed_96_GT]

Maybe it was a traction problem between shifts?

 

[Notchbck93]

Your theory is correct my friend, this is why a lot of hardcore enthusiast that are looking to extract every ounce of power will not run a high volume oil pump. They will B&B a stocker and run stock pressure.

Most street guys say ahh whats 5-6 hp, I'd rather have more than enough oil for long street reliability for 10 + years.

12.90's -13.0's would be a converter away based on your current times.

If you are going for all out numbers, run a short belt that only runs the alt and water pump. Ditch the spare and jack.

A tad more you say... drain a quart of oil out for a bit less windage. MM&FF proved this was worth a tenth and air your front tires up to 50 psi. Drag lites would be better, but this is a budget post.

 

[joshheat25]

I never heard this and I know that before I had changed my shift pressure and points my auto sucked..

 

[MaxedGT]

Your theory is correct my friend, this is why a lot of hardcore enthusiast that are looking to extract every ounce of power will not run a high volume oil pump. They will B&B a stocker and run stock pressure.

Most street guys say ahh whats 5-6 hp, I'd rather have more than enough oil for long street reliability for 10 + years.

12.90's -13.0's would be a converter away based on your current times.

If you are going for all out numbers, run a short belt that only runs the alt and water pump. Ditch the spare and jack.

A tad more you say... drain a quart of oil out for a bit less windage. MM&FF proved this was worth a tenth and air your front tires up to 50 psi. Drag lites would be better, but this is a budget post.

High stall torque converter is the next mod on my list. I didn't want to do anything else till I figured out where that power loss was coming from. I figured the torque converter would be good for a 13.2 at least.
The belt idea crossed my mind but I'm not sure if I want to run without p/s at 100+ mph.
I usually pull the spare and jack and pump the front tires up to 45 psi but forgot to that night cause my cousin showed up who I hadn't seen in decades.
I thought about dropping the oil level as well but I'd rather be safe than sorry. It probably would be fine, but I don't want to risk it.
I appreciate your input NB93, I can tell you know what you're talking about.

 

[CobraRed_96_GT]

I could probably document this with dyno numbers - that would help.

 

[MaxedGT]

I could probably document this with dyno numbers - that would help.

I'm really curious what the dyno would show. That would be cool!

 

[MaxedGT]

I'm really curious what the dyno would show. That would be cool!

Looking at my time slips, most of the gains were made in the first 1/8th. Can you duplicate going through the gears on a dyno?

 

[Notchbck93]

I used to be hardcore in taking a plain package and making it run what bigger packages could run all by paying attention to the details and hanging around with a few dyno heads ---everything had to be proven.

Here is an excerpt from an oil pan manufacturer.

Billet Fabrication - Oil Pans

"Drag-racing-champion Bill Maropulos is another engine builder who has provided invaluable feedback since becoming one of our customers. Maropulos reveals that he has realized dyno-verified power gains after taking the screen out when using a high-kickout pan. He also tells us that, after starting out with eight to nine quarts of oil in a large pan, cutting back to six quarts resulted in more power on the dyno. Dropping to four quarts was even better: The difference was in the range of 25 to 30 horsepower!"

Take into account that this may be on an 800 hp N/A engine. This is why I was saying that you could realistically expect .10 out of dropping a quart. No big gains, but it could make the difference of saying you have a 13 second car or a 12 second car.

There is also a reason why I said a quart and to not go overboard without extensive R&D. What you see on the Dyno isn't what always happens at the track as the oil sloshes to the back.

"No, we do not recommend draining half of your oil before going out on the track! If someone is inclined to experiment along these lines, we would hope that testing would be accomplished carefully and gradually, with an exceptionally close eye monitoring the oil-pressure gauge at all times — especially during braking — and a ready finger on the kill switch!"

This talks about reducing windage..

Home

As far as no P/S... I've been there done that, you will not feel it on the big end. You will feel it as you turn around at the end to go to the ticket booth and turning into your spot.

My Notch weights 3360 with me in it and it turned a 12.501 @ 109 with a lousy 1.771 60ft spinning the tires.

This was with a 2.95 first, 3.55 diff gear and an over tall 27 inch hoosier on the back with a 4000 rpm launch; no sidestep. Car weights a portly 3360 with me in it: full interior with A/C.

With a PMS, I felt I could have dialed out another .2 It was starving for fuel on the big end, but I was putting myself through DeVry and well, money was tight.

With a proper 26" I should have dialed out another .2 with a 1.65 or so realistic 60 ft.

I never went back to the track and threw an S-trim at the car for fun and as a grad present to myself. At 30 years old, I no longer care what the thing will run at the track and am happy to still have a car I can get decent mpg with and have the ability to cruise down mememory lane with on sunny days.


Good luck and be safe on your quest into the 12's.

 

[bhuff30]

I would argue that despite the slight loss, it may be a good idea for you to keep the firm shifts. During a soft stock shift, the clutchs and bands slip more than a firm and positive shift. When you increase the power, the shifts tend to take even longer with more slippage of the bands and clutches. Of course, this slippage wears the parts and creates excess heat, and heat is the biggest enemy of automatic tranmissions, right behind 16 year olds doing neutral bombs. Where you are making a lot of passes in the quarter each year, with a significant increase in power from stock, a firmer more positive shift should help the transmission last longer. I think it's fair to say that Ford still doesn't know how to make the best automatic transmissions, so you it's important to take care of your transmission.

As an extreme example, my 2.3 came stock with a A4ld, which is a light duty 4 speed automatic. The engine was rated at 88hp from the factory; After some tweaking, I was making closer to 240hp at the crank, which is nearly 3 times the origional power. I took a video of the speedo and tach, and after analyzing the video frame by frame, I realized the 1-2 shift was taking nearly .4 seconds to complete. Needless to say, this transmission lasted less than 20k miles. Now, I've got a C4 with a shift kit that shifts nice and firm.

 

[MaxedGT]

I would argue that despite the slight loss, it may be a good idea for you to keep the firm shifts. During a soft stock shift, the clutchs and bands slip more than a firm and positive shift. When you increase the power, the shifts tend to take even longer with more slippage of the bands and clutches. Of course, this slippage wears the parts and creates excess heat, and heat is the biggest enemy of automatic tranmissions, right behind 16 year olds doing neutral bombs. Where you are making a lot of passes in the quarter each year, with a significant increase in power from stock, a firmer more positive shift should help the transmission last longer. I think it's fair to say that Ford still doesn't know how to make the best automatic transmissions, so you it's important to take care of your transmission.

As an extreme example, my 2.3 came stock with a A4ld, which is a light duty 4 speed automatic. The engine was rated at 88hp from the factory; After some tweaking, I was making closer to 240hp at the crank, which is nearly 3 times the origional power. I took a video of the speedo and tach, and after analyzing the video frame by frame, I realized the 1-2 shift was taking nearly .4 seconds to complete. Needless to say, this transmission lasted less than 20k miles. Now, I've got a C4 with a shift kit that shifts nice and firm.

I agree with you on the importance of quick shifts to reduce clutch and or band wear. i did the j-mod for just that reason, which is better than using a tuner to just boost shift pressures. With the boosted pressures and the j-mod it was maybe overkill. Infact an unexpected downshift on my car can be dangerous with the boosted pressure and an upshift under heavy throttle, could put me in a ditch. I highly recommend the j-mod and a tranny cooler.

 

[CobraRed_96_GT]

Looking at my time slips, most of the gains were made in the first 1/8th. Can you duplicate going through the gears on a dyno?

If i put my trans in manual gears it will sustain line pressure, therefore using the pump to up the pressure then it's contained for any future shift, pump should be working the whole pull. I can talk to my local tuner about it to see what he says.

 

[MaxedGT]

I'm heading to the track again this Saturday. I'll see how it runs this time out. I plan on trying bracket racing for the first time, so I won't be playing with adjustments though.

 

[MaxedGT]

Went to the track on Saturday. First run 2.089 60ft, [email protected] mph.
Not bad But felt like I was losing grip even though the 60 ft was ok. So I pumped up my air bag in the rr spring to 15 psi.
Next run, 2.016 60 ft, [email protected].
Much better I figured I had found my lost power.
then my buddy says, arn't you going to pull out your headlight?
Pulled out the right headlamp to allow air into my stock air intake with the silencer removed. That's how I always run.
1.971 60ft, [email protected]!
Ya!! Shattered my old previous best.
Then ran again.
1.975 60 ft, [email protected] mph.
I'd say it's pretty conclusive. Increasing the shift pressures does rob power.

 

[Notchbck93]

Stall and slicks man,,, I want to see me some 12's out of your ride!

 

[MaxedGT]

Stall and slicks man,,, I want to see me some 12's out of your ride!

Yah! I can almost smell them 12's!
13.1 anyways.