I currently run a 4lb lower with other mods and ran a best of 12.798@106 on mt's streets, with race tune. I currently have an appointment with jdm on june 2nd for a 6lb pulley install and the full leanth headers with mid pipes. I can't afford a dyno tune with it and i am kinda worried about that. Jim and Jim jr know me very well and always take care of me so that makes me feel very comfortable. My question is for SAFTEY sake. Should i stick with the 4lb lower and get the headers and maybe put that extra money into just say an electric fan, or do i just say the hell with it and make some really good numbers with a 6lb and headers. Thanks guys and leanne.

 

The headers will lose a pound or two of boost over your current setup, so boost-wise you'll likely be about the same.

Thing is the headers will need a re-tune to run best. Putting LT's on will richen the A/F a fair amount, so although it won't make you lean which could hurt the motor, it will not make as much power as it could until you re-do the maf transfer to compensate and get your a/f in line.

Jody

 

Yeah what Jody said is correct. Most people thinkheaders will lean you out but it;s thw opposite.

 

Eddie you should be ok with the 6. Are you using the SCT or a chip?

 

get the money some how and get the dyno tune or i would wait till i could afford it.

 

Al, i'm using the sct 4 bank chip. I don't have the tuner. And i would love to afford the dyno tune but can't for now;my friend ran a 12.30 at jdm day with the 6lb pulley headers, cai and the hand held tuner. I realize that every truck is different but he had no dyno tune and he drove all winter without pinging.

 

You should be ok ,just get the chip reburned and talk with Jim.

 

if you dont have a ported blower.. i would recommend staying away from the 6lber.. I'm currently running the 6lber on the stock blower, and i know quite a few guys running better #'s than me on the dyno and at the track with a 4lber and a stock blower.. the 6 just creates waaay too much heat.. just my opinion though.. maybe you'll be luckier than i am... good luck

 

Anyone know on average how much richer headers make the air/fuel ratio?

 

Almost one full point on mine.

Jody

 

I did'nt know it made the burn fatter w/a header install?

Why is this so? And... Would this also be true if a guy were to remove the cats? (namely me w/my new cat-less mid pipes)

Rich

 

usaf eagle thats the predicament that i'm in. if i go bigger i might break something and if i stay where i'm at it will be safer but might not be the numbers that i', looking for. I think im going to stay with the 4lb and maybe get an eltric fan or something.

 

IF the Ford PCM works like the Chevy LS1, it's because of adaptive learning and how they use short term fuel trims. The hearers make you run lean at cruise (closed loop), the PCM sees this, adds fuel during closed loop, and adds even more for safety during WOT.

 

Same here. I was really disappointed with my headers, until Sal straightened up the a/f ratio.

 

spend the money on the dyno tune.

I put headers on last year and my truck was a mess (do a search on my name with all my problem posts). After doing plugs, whole new set of coil packs, new o2 extenders, new o2's, went to ford for a drivability scan..............still problems.

Went back down to Jim for another dyno tune with the new SCT software and everything has been fine.

Headers made my a/f so rich, even at part throttle that it was dumping so much fuel it was causeing my o2's not to work correctly.

Pay now..........or pay later.

Just have him do a dyno tune. Not only are you protecting your self, but you will get optimum results.