TOPIC: 2004 Mustang 4.6 Groove job

Hello guys.

Just did my buddy's 2004 Mustang 4.6l. He has it all modified out. He should be posting to this thread when he gets a chance.
What's good about this is that he is very into his car and knows everything about it. He pays attention to his computer readings, responsiveness, and all that.
When he does his readings, he'll post the graph's or whatever he has here.

My story to say is: I did the groove with the medium bit because I didn't want to cut through and mess up his pretty chrome finish with JB quik. He put it back together and went into the OBD and set the idle lower. (When figuring out where to put the groove, planned to use the business card spacer, but seeing how he could tune the car.. meaning change the position of the throttle through his doo-hickie computer. I went with folding the business card in half and having it stuck between the idle set screw and body)
Everything went good. As my buddy took off it was obvious that he was not expecting the car go break loose and try to throw him into my neighbor's yard. My brother and I are still laughing about it. My buddy knows how to drive; his car kicking out from him and heading towards the sidewalk... is just plain funny. I do think that if most other people were behind the wheel, there would have been a crash.
When he came back, he said that he 'was not expecting that jump from 1st-2nd'
Basically, all is good and I think he's pretty damn impressed.
I'll be waiting for his posts on here. I might have to remind him though.

Heathen

HeathenDM's Buddy here. The report for the 20 minute drive home can be summed up best in 16 year old girly text speak "OMG!!!!." 200 to 300 rpm drops in 1st through 3rd to maintain Pre-groove speeds. 400 to 550 rpm drops to maintain Pre-groove freeway speeds. Given my present rear end is a 3.73 set the mpg savings could be serious. I typically get 11.5 to 12 mpg at 75mph at 3400 rpm on the way home I was at 2900rpm + / - 50 and right on 75 mph. Mathematically I think great mpg gains could be expected. BUT, practically I don't know if it will happen.

I'm glad Heathen and his bro got a good laugh but you have to put that in perspective. The car is modded out and the last Dyno tune (Pre-new exhaust, ignition set, injector upgrade) she came in at 380hp (temp / alt adjusted) at the wheels. I have been driving thirty years in various mid to high end 1/4 mile cars. I have been driving this one for seven years and, until tonight, have never been out of control ( at the edge sure, but never over). So when I shifted to second with a bit of angle on the wheel for show, and the rear end broke loose and slid 20 degrees further out than it typically would at WOT - I was an instant believer. The low end acceleration increase can't be ignored even when the only Dyno is the seat of your pants. Through the OBD II Tuner and laptop I keep baseline and comparison numbers for all mods. Because I can accelerate more quickly now I might, well, most likely wiil, consume my high end fuel savings enjoying my low end fun.

After a few tune tweaks, because my ECU is having a hell of a time trying to figure out what is going on with the A/F ratio; and, after the novelty of my new found low end power has mellowed, I will try to post the before and after numbers and graphs.

Finally, so there is no confusion, this is not a stock 4.6 mod motor. There are no internal changes yet but as the pics show engine mods include a BBK CAI with Big Mouth MAF, Accufab TB, C&L Plenum, X-Treme Tech COPS, larger FIs, Steeda UDPs and a Borla Street / Strip exhaust (High flow Cats can be swapped for straight pipes in ten minutes) blowing through Magna Flow mufflers.

I am certain that I will be able to work to bugs out of this mod (just as I have had to to make all the rest work best together) so this shouldn't be premature. Huge thank you to HeathenDM for turning me on to this concept and doing the mod work and big thanks and my highest respect to gadget man not only for thinking it up anddeveloping it but most of all sharing it instead of focusing on the bottom line. Nice to know there are still people out there who maintain the humanity in being human. Best of luck with your tour.

sounds great but one thing you didnt check the exhaust temps and water temp is lower. this is worth an extra peek so check it out a litte groove makes a big difference. Dan gadgetman mo.

Hey Heathen's Buddy,

Great testimony! Thank you for all the info and the great post. Looking forward to mpg gain report! Can this really be this fun?

Still enjoying my noticably increased power (can break tires loose shifting into third now, kinda fun) more data, more learning, but still tweaking and dialing in. Have not been through an entire known fuel amount so still no MPG data. But, it was looking good (122 miles on odo at half tank where it used to be 100 to 104. Not very precise I know but . . .

After finally tracking down a vac leak in Right bank pcv return line I was able to get the idle in drive and neutral steady, solid and predictable. Then driving home two days ago everything goes south. Think Antartic South! Motor will barely idle and when it did it was either choking and gasping at 520 - 600 RPM OR would "idle" at 2500 and then accelerate as high as I would alow it to before cutting the motor or loading it in gear. Pop goes the hood and after a little looking I find the left bank PCV valve return hose had popped completely off. In the days leading up to this I had noticed a little bit more Vac noise but, wrote it off to the recent tuning and fuel management tweaks making the motor sound different than usual. However I also noticed that I only got about 30 miles for a quarter tank of gas. A Serious MPG loss. So, put it all back together - now with a nice little zip tie to keep the return hose on the valve. Reset all the tables and most recent best working tune and it's running fine.

BUT, an interesting thing I also noticed was that the car seemed to have even more low end power and a longer power band when the PCV valve wasn't pushing hot, oily crankcase fumes back into the intake. If you read my first post you probably picked up on the street/ strip nature of the car. If not, I get out to the quarter as often as possible so, as an OFF ROAD ONLY issue, can anyone tell me if I seal the PCV intakes on the intake and fabricate a hose and oil seperator / collector to keep the nasty off the track can I expect power gains? Also, what effect would that have on MPG?

I will get those MPG numbers on the current emissions compliant set up as soon as burn through the 16 I put in today. Hopefully that will be quite a while. . . The whole point right?

Hi
To take care of your pcv line discharge I recomend using what is called a condensator, the web site is The domain name condensator.com is for sale . This will collect all the junk coming through in a jar and let the gas or fumes go to intake to be burned. I have been using a unit for about 7 years and like it.

Thanks Aaron

Aaron, Thanks for the idea. If I get the MPG gains in my car I'll probably be back at Heathen's with my Other Throttle Body and might consider the Condensorator as an additional item for the Road only cars. But, at the track emissions are not an issue. What I am wondering, as a low buck track only idea - will capping the PCV inlet on the intake and routing the PCV line to a low tech collector increase efficiency by decreasing heated air in the mix? Over the short runs I am not concerned about the sludge so much and I am running with straight exhaust pipes (no Cats) so emissions control is no problem. Of course, have to put it all the EPA stuff back on to drive home. Maybe the better question to ask though, if I cap the inlet and run the PCV line to other than the intake or exhaust would it hurt the motor and / or provide power gains.

My logic, if any, is give the motor the coolest, purest, A/F mix possible (w/o any space in the mix being consumed by heated scavenged hydrocarbons from the blow-by) and get more power but, possibly loosing mpg. Or not? As much research as I have done it seems Mopar guys like PCV deletes on modified motors. Track only guys all seem to loose the PCV return but, such seriously modified motors burning alcohol do not really provide a useful point of reference. Most surprising, looking through the mustang pages, the searches turned up nothing. Really, surprising given that Mustangs are one of the most universally modified cars in the country. As a side note, what really surprised me was my inability to find anyone on the Mustang forums talking about the Groove. These are people that will spend $500 on a tuner and $800 on an aftermarket exhaust to get a 15 to 20 hp and 1-2 mpg gain! Not a word about the groove. I am guessing that those who know want to keep it to themselves.

BTW, Dan you were right, H20 and exhaust are both cooler. I still don't have the hard graphs and numbers but, should have all the preliminary data once this tank is gone. Thanks to all.

Ok, burned through the 1st 16 gallons. My MPG gain was 2.7 MPG. BUT, I have to admit that the driving was much more enthusiastic than usual. I just can't get over the improved acceleration and throttle response. In fact, the last 1/8th of the tank was running 1/4s and 0 to 60's to compare to the befores. Frankly, as aggresively as i have been driving i would have been happy to maintain the 12 to 14 MPG i was getting. To still see an increase really has me convinced. Well that and the consistent negative trims the reader is reporting.

So, I put another 16 gallons in tonight, cleared the tables again so the ECU isn't so confused and now I will make a conscious effort to return to my typical driving and shifting habits for this tank. Once I find my serial cable I will get the data I keep promising up as well.

As for the questions about track configurations for the PCV, I rerouted the return line through an old style catch can with a breather. My IAT dropped 85 degrees F immediately. Nice cool dense clean air a plenty now.

HeathenDM - Did you get any other pics INSIDE the engine bay? If so please post as I just found an unconnected hose at the back of the plenum when searching for vacuum leaks. I can't remember reinstalling this hose after the original post grove install. In fact I can't remember installing this hose when I went to aftermarket plenum. (You've seen my bay, might not be clean but its put together to stay together and I would have clamped this hose if I put it back on. No clamp and the fact the engine doesn't respond much differently whether it's on or off and I'm really wondering.

As for the PCV redesign found plenty of available oil catch cans on import tuner websites. (They are for 1.6 to 2.2 liter engines so maybe I'll get a couple for each bank. Or, I could get six weld them up like a six pack and people will just think I'm running two Optimas in tandem.) No matter how I do it the nice thing is they can be set with a direct breather out (track) or with a return line (street). No more gunk and oil in my uppier intake, valves or cylinders and legal. Win, win.

Finally, until I get this missing hose question cleared up I'm thinking that I will see some significant improvements over the 2.5 to 3.5 mpg increase I did see. Once I download my last data runs I will get the newest numbers which should be as good as I'll get without additional tuning. Then I'll post those numbers. Thanks again.

i texted that pic, maybe you can manipulate it on your phone, but that was the only one I took of the engine bay

Check out a PCV catch can. It's about half the price of this condensator, looks to be about 1/3 to 1/2 the size, don't usually have a glaring yellow bracket, and does the same thing. Since it's smaller, you'd have to drain it more often, but even then I think it's only every thousand or 2 miles for the smaller ones.

Many to choose from - just google it.

Ok, so my dear sweet wife decided to fill up my car since she drove it. There go the numbers on that tank. But, two good things. First, she noticed the power increase and smoother running engine enough to comment about it and she couldn't care less about performance. If she noticed it enough to comment I know it must be significant. Also, Since i was supposed to be doing the honey do list when Heathen was grooving my car - she has no idea what was different. Still have to get her TB done. Mother's Day? Maybe that and a nice new vacuum cleaner. That's a good idea right? (For those who are worried, just kidding. She's not my mom why would I get her something?!)

Seriously though, the second thing, the engine was tuned for 91 Octane but, my wife filled it with 87. (told you she didn't care about performance.) I drove for two days before I realized what had happened and there was no noticable difference. Can This be right? If so could someone explain how this could be?

As for MPG increase, right now I am calling it 17% but, my "driving style" is likely the largest factor keeping that number down. I have some free time tommorow so I am going to try to get those before / after graphs up i keep talking about.