|
Author
|
Topic: Tuning turbo 347
|
ratfast
¯
Member # 8720
|
posted
 
 
My brother in law put a single turbo kit on his 347. Utilizing a 70 mm throttle body, 185 afr heads, holley systemax intake, 56 lb injectors, 76 mm mass air and approximately 8 lbs of boost. initial tune showed 455 hp and 499 ft lbs of torque at rear wheels. problem is mass air maxes out voltage at 5200 rpm causing engine to go lean at any higher rpms. What have other turbo set ups used to cure this? Stand alone? Mafia set up? Any help would be appreciated.
--------------------
'93 White notch all stock
Posts: 604 | From: roseville, california | Registered: Oct 2008
| :
|
|
S351-R
CAFords OG
Member # 1605
|
posted
The MAF is pegging. Sounds like it needs a different MAF. Judging from your description, the car probably has a C&L MAF cause they're the only ones I know that make a 76mm MAF. The problem with it is that it uses the stock electronics and employs a 'calibration' tube to 'trick' the MAF. You could use a MAFia, scale the engine displacement and the fuel injector slope values in the tune and extend the current MAF's tuning range. I'd rather use a different MAF with different electronics that have an extended tuning range (like an SCT Big Air MAF). Judging from the boost and the horsepower the combination is making, a cheaper alternative may even be a 90mm Lightning MAF. Is the MAF currently set up as a 'suck-through' (before the turbo) or 'blow-through' (after the turbo)?
[ November 06, 2008, 03:42 AM: Message edited by: S351-R ]
Posts: 344 | From: Earth | Registered: Jul 2002
| :
|
|
ratfast
¯
Member # 8720
|
posted
Unit is currently a blow through after the turbo. Thank you.
--------------------
'93 White notch all stock
Posts: 604 | From: roseville, california | Registered: Oct 2008
| :
|
|
4MY8TERS
¯
Member # 7840
|
posted
90mm maf, I have a 306 twin turbo pushing over 500 with no problem
--------------------
1985 Notchback-393w Vortech
1991 Convert Lx-H/C/I-Vortech
1984 T-Top 306-H/C/I
Posts: 2337 | From: THE GOLDEN CITY AKA SFC | Registered: Aug 2007
| :
|
|
Fostang
¯
Member # 3752
|
posted
definately pegging the maf.
problem here is the blow thru portion. even if you do get say the sct big mouth 3000 i think you would still peg it. i was seeing about 2400 with a 302 and 15 psi. however that was with a centrifugal supercharger on a draw thru design.
blow tru will usually require a maf with a higher kg/hr rating. so my recomendation on the cheap would be a lighting 90 mm mass air with a maf extender and tunning i used a tweecer rt.
i dont see why you wouldnt be able to puch about 550 rwhp with a347 and 8 psi.
--------------------
67' Fastback TT 408
67' Camaro Lsx
64' Corvette Fuelie
57' Chevy Bel Air Lsx
68’ Pony Convertible
66’ Pony Coupe
Posts: 3011 | From: Stockton/Danville | Registered: Nov 2003
| :
|
|
ratfast
¯
Member # 8720
|
posted
Thanks for the advice. My bro in law says thank you also. Dammit, now I have to do a little more work to my procharged 342 to keep up.....
--------------------
'93 White notch all stock
Posts: 604 | From: roseville, california | Registered: Oct 2008
| :
|
|
Fostang
¯
Member # 3752
|
posted
definately pegging the maf.
problem here is the blow thru portion. even if you do get say the sct big mouth 3000 i think you would still peg it. i was seeing about 2400 with a 302 and 15 psi. however that was with a centrifugal supercharger on a draw thru design.
blow tru will usually require a maf with a higher kg/hr rating. so my recomendation on the cheap would be a lighting 90 mm mass air with a maf extender and tunning i used a tweecer rt.
i dont see why you wouldnt be able to puch about 550 rwhp with a347 and 8 psi.
--------------------
67' Fastback TT 408
67' Camaro Lsx
64' Corvette Fuelie
57' Chevy Bel Air Lsx
68’ Pony Convertible
66’ Pony Coupe
Posts: 3011 | From: Stockton/Danville | Registered: Nov 2003
| :
|
|
93PONY
Mr. Valve Events
Member # 60
|
posted
I would NOT recomend an SCT or lightning/Cobra maff for any 5.0. Nor a Mafia. They are very difficult to dial in for all driving conditions as there is no way to datalog load on these cars.
I run a Pro-M calibrated for Blowthru on my turbo setup. I'd recomend that route along with a stand-alone type tuner that allows RPM based air/fuel adjustments rather than maff-based. Yes, it's true it's not as 'good' of an all-around tune as Maff transfer function based tuning, and the air/fuel will change slightly at different altitudes and air temps, but.... The part-throttle A/F will be VERY close for all driving conditions outside of WOT & will therefore yield better drivability without having the tuner spend a ton of hours dialing in the transfer function.
I run a PMS & couldn't be happier with the way the car drives/performs.
I should also state that I'm an SCT dealer and tuner. We sell SCT products and have SCT Maff's in stock. And yet I don't run an SCT chip or Maff on my own Blow-thru turbo application. If I had an OBD2 car, I would run the SCT stuff, but for the OBD1 cars, IMO it's best to run a calibrated maff, and for a blow-thru turbo setup it's easier to dial in the tune with RPM based fuel adjustments.
BTW, with the PMS it doesn't matter if you peg the maff. You can still richen up the mixture based on RPM. Same goes for the SCT stuff, it's just not as easy to do.
My advise:
Buy a PMS, the datalogging software for it, and an AFX wideband from NGK.
I can tune the PMS if needed as well.
[ November 06, 2008, 03:06 PM: Message edited by: 93PONY ]
--------------------
www.advancedenginedevelopment.com
SCT dealer
Dynotuning
(916)715-7569
Posts: 4265 | From: Fair Oaks, CA | Registered: Nov 2000
| :
|
|
fastertoys1
¯
Member # 5270
|
posted
quote:
Originally posted by 93PONY:
I would NOT recomend an SCT or lightning/Cobra maff for any 5.0. Nor a Mafia. They are very difficult to dial in for all driving conditions as there is no way to datalog load on these cars.
I run a Pro-M calibrated for Blowthru on my turbo setup. I'd recomend that route along with a stand-alone type tuner that allows RPM based air/fuel adjustments rather than maff-based. Yes, it's true it's not as 'good' of an all-around tune as Maff transfer function based tuning, and the air/fuel will change slightly at different altitudes and air temps, but.... The part-throttle A/F will be VERY close for all driving conditions outside of WOT & will therefore yield better drivability without having the tuner spend a ton of hours dialing in the transfer function.
I run a PMS & couldn't be happier with the way the car drives/performs.
I should also state that I'm an SCT dealer and tuner. We sell SCT products and have SCT Maff's in stock. And yet I don't run an SCT chip or Maff on my own Blow-thru turbo application. If I had an OBD2 car, I would run the SCT stuff, but for the OBD1 cars, IMO it's best to run a calibrated maff, and for a blow-thru turbo setup it's easier to dial in the tune with RPM based fuel adjustments.
BTW, with the PMS it doesn't matter if you peg the maff. You can still richen up the mixture based on RPM. Same goes for the SCT stuff, it's just not as easy to do.
My advise:
Buy a PMS, the datalogging software for it, and an AFX wideband from NGK.
I can tune the PMS if needed as well.
Posts: 2178 | Registered: Jan 2005
| :
|
|
|
Email this post to someone!
Printer friendly view of this Ford topic
