Best Way To Spend 2K
07-31-2013, 08:27 PM
#11
2nd Gear Member
Join Date: Sep 2011
Location: Ohio
Posts: 325
The factory 88 lph fuel pump with a well tuned engine can support around 310 hp, at the flywheel. A 110 lph pump will support around 375 hp, which I ran for many years, with TF TW heads, Holley intake, 73mm MA, 65mm TB, 1.7 rockers, Crane 2031 cam, long tube headers, and 2.5" exhaust, running the quarter mile at 12.9 at 108 on street tires, leaving the line just above idle. I currently run a 190 lph pump, with my 369, making 425 rwhp, which is about 490 at the flywheel. I have never run a fuel regulator other than the factory regulator. For most 5.0's, the best TB size is 65mm, but you don't give up much to go 70mm. For the MA, I'd go with a 73mm, 75mm, or 76mm, whichever you prefer. If you stroke the engine you need bigger of both. As Duncan stated, the MA needs calibrated to your injectors, which you either buy already calibrated, or you can use a tune to adjust them. Most people on here don't like C&L MA sensors, but I do, had good luck with them, and you can recalibrate them with a $30 tube to different size injectors. The factory 19# injectors are good for about 330 hp (at the flywheel) at 100 percent duty cycle with a well tuned engine. 24# are good for a little over 400 hp under the same conditions. You can't road race at 100 percent duty cycle, because they won't live long (should stay under 80 percent), but you can drag race at 100 percent duty cycle. All calculations come from the Mustang Performance Handbook, written by William Mathis.
08-01-2013, 07:18 AM
#14
D.R. THE PATHETIC DORK
Join Date: Jun 2007
Location: West Virginia
Posts: 30,863
08-01-2013, 10:22 PM
#15
What's up guys. I'm new to the forums and the Mustang world. I just picked up a 1991 GT that is pretty much stock which the exception of shorty headers and Flowmaster cat back. I'm trying to decide what the best way to spend my first 2 grand would be. Option 1 is a BBK cai, BBK 65mm throttle body, Trickflow upper and lower intakes, an SCT tuner and 3.73 gears (up from 2.73). Option 2 is 170 mm Trickflow Twisted Wedge heads, TF stage 1 cam and 1.6 Roller rocker arms. I want to leave the lower end stock and N/A. Any advice would be greatly appreciated.
08-02-2013, 06:48 PM
#17
2nd Gear Member
Join Date: Sep 2011
Location: Ohio
Posts: 325
Also, to quote my tuner, "it has a baby cam", with 223/227 duration. Say what you want, it's a blast to drive! More seriously at the track, I leave the line at about 2400 rpm - any higher and it lights the tires, and that's with MT ET Streets (and normal front street tires). With the suspension, there is no transfer of weight to the rear, or lift of the nose; the car stays dead level. The 60' time was 1.71.
08-02-2013, 08:25 PM
#18
4th Gear Member
Join Date: Jun 2011
Location: Indy
Posts: 1,353
Why so little duration? I would think road racing you'd be at higher rpm's more of the time, wouldn't a wider duration help you with that (not taking in ramp rates, lobe angles, etc) and shift the power curve higher in the rpm's?
Is that 369 a big bore (Dart or the like) or stock block? Just wondering
Is that 369 a big bore (Dart or the like) or stock block? Just wondering
08-02-2013, 10:12 PM
#19
2nd Gear Member
Join Date: Sep 2011
Location: Ohio
Posts: 325
It is a big bore Dart SHP block. I was trying to compromise on the duration, it is a street car. That was the toughest decision of the build (302 versus 351 based block being the other big one), and I may go bigger on the cam one of these days.... I gave up trying to run rear street tires, they were a complete joke. You should be enjoying your new engine soon!