MS3 prc 5.3 2.5 heads RWHP
06-20-2008, 07:03 PM
#1
MS3 prc 5.3 2.5 heads RWHP Just got done putting heads and cam in, has the typhoon intake, obx longtubes, all that good stuff. M6...car put down 412RWHP and 359RWTQ. I haven't dynoed it with the new clutch, had the factory clutch in the car, it would slip on the street, even with stock setup if you dropped the clutch. MCracing said it "wasn't slipping on the dyno" They said 412HP is all they could get out of the car! How possible do you think that is? M6 with the MS3 cam and the stage 2.5 5.3 heads. The dyno said the AFR was 13.2 but when i put the LM-1 on the car, at WOT it goes from 11.8-12.4 AFR. Smells rich as well, but they're dyno was saying it was in the low 13's and that is how they tuned it, they said they're wideband was more accurate...
06-20-2008, 09:02 PM
#6
Just got done putting heads and cam in, has the typhoon intake, obx longtubes, all that good stuff. M6...car put down 412RWHP and 359RWTQ. I haven't dynoed it with the new clutch, had the factory clutch in the car, it would slip on the street, even with stock setup if you dropped the clutch. MCracing said it "wasn't slipping on the dyno" They said 412HP is all they could get out of the car! How possible do you think that is? M6 with the MS3 cam and the stage 2.5 5.3 heads. The dyno said the AFR was 13.2 but when i put the LM-1 on the car, at WOT it goes from 11.8-12.4 AFR. Smells rich as well, but they're dyno was saying it was in the low 13's and that is how they tuned it, they said they're wideband was more accurate...
I dont call the typhoon intake and OBX headers the "good stuff", in general not all cars are dyno queens.
With the mods in my sig I put down 396 w/ a dirty air filter and a fuel filter that prob needs a change. It was VERY close to 400 RWHP w/ a HEAVY DS and Moser rear.
Had it been a stock driveline it would prob be in the 410-415 range all day, cam only. The ported 90 prob isnt up to its full potential due to the stock heads but Ported Fast 90's fall off at around 280 cfm anyways, so anything above that is useless, no matter what the flow bench sheet says and I know that typhoon isnt better flowing then the fast.
Its all about under the curve flow.
06-20-2008, 09:10 PM
#7
I've never sat in or particepated in a chassis dyno session, just a spectator. I'm not sure how much load they put on to measure the output but if there is a measurable load I would guess the clutch would slip.
I know on a flywheel dyno they put a considerable load on the motor via a water break. You can tell when they load the break. That's how they determine engines output, plus a little math/physics etc.
I know on a flywheel dyno they put a considerable load on the motor via a water break. You can tell when they load the break. That's how they determine engines output, plus a little math/physics etc.
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06-20-2008, 09:56 PM
#9
the obx headers aren't bad, the only bad thing about them is they are only 1-5/8 and not 1 7/8 they are stainless though, and look great. The intake, looks really good, but i'm not sure about perfomance, i just know it was better than the LS1 intake. I have another appointment at MCRacing July 8th, my new DFX clutch will be broke in by then, hopefully the #'s go up 30HP or so with the new clutch....if not, its either tune or intake..or both i would imagine. You wanted to know about the MS3, i love the idle..sounds bad *** and it peaks at 6400-6450..perfect for stock rod bolts. The low end with 3.42's is noticabely lower than the stock cam, but when it hits about 3 grand...it gets crazy all the way up to redline no way street tires will hook up. I'll let you know the 8th of what it dynoes at again. Thanks for the input!
06-21-2008, 07:23 AM
#10
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This was on a dynojet not mustang dyno! His y-pipe is only 2.5" not 3" like most and has a good high flowing catback. The only thing that suck is the Alu 40lbs intake holds alot of heat when it sitting still on the dyno. Ice down the intake right b4 you dyno it next time. Their is no reason for my smaller cam only (231/237) on stock 99 heads and ls6inake should make 1 more hp and 20 more torque then you. Im 100% sure it was your clutch it was stock with 86k miles. MC racing is good a WOT tuning they just dont do the driveability.
06-21-2008, 08:55 AM
#11
If that's MCRacing in KC then it's a DJ 248. Your numbers should DEFINITELY be higher than that. I went there a few years back right after I installed my 233/239 cam with an LS6 intake, lid, pacesetter LT's, 3" ORY, and magnaflow C/B and put down 399RWHP/359RWTQ and mine was VERY lean at the pull (like 16:1!!). With a dyno tune and those heads I would've expected around 430-440RWHP. Oh and mine was a '99 T/A M6 as well with no known clutch slippage.
06-21-2008, 10:51 AM
#13
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I only did 150 mile break in on mine and it has 25k miles feel the same as when i put it on. I got on it but with no speed shifts intil i got around 300 miles
06-21-2008, 10:55 AM
#14
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Another car that went to MC racing with same cam as you and stock ls6 intake and heads and crappy MAC mid headers and catted Y-pipe put down 401with auto trans! Hell my car with just boltons did 365wheel torque. So you will pick up a good bit of HP! At the lowest you should be 430ish!
06-21-2008, 04:21 PM
#15
sounds good, i'll know at the track..i can't wait till i get off 2nd shift so i can go down there! I'm prolly gonna put the UD pulley on before i go again, needs belts anyway....know anyone with good hooking tires i can buy for cheap??
06-21-2008, 05:33 PM
#17
06-21-2008, 05:48 PM
#18
His numbers are not inline for this particular dyno. I've been there several times with M6 cars and have seen (my last f-bod included) multiple cars laydown 400RWHP with LS6 intake and similar or smaller cams. So are you saying PRC heads are only worth 15-20RWHP...doubt it plus his torque is down even from cam-only cars on that dyno.
06-21-2008, 08:57 PM
#19
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I think Mc's dyno reads a little low, but I would definately hope for some higher numbers once you get that clutch in... I think the tune was VERY conservative as well, I would expect at least 430 RWHP 