Bob, One of us will do a dyno run or a pass at the track one of these days.

 

Yes and depending upon abient air teps, whether you have a huge set of fans pushing cool air at the front of your car, how many passes you do etc. etc. the results will vary. But if you truly have picked up 55 or 75 HP it should show up.

 

As it sits now, my STR, with its free flowing exhaust and stock pulley, has a much noticeable improvement in throttle respoinse, "Seat of the Pants" torque, and HP. Like you, I'm curious as to the measurable changes the exhaust and smaller pulley can make.

 

But don't you still have the stock exhaust manifold (headers)? Aren't those choking the flow?

(I still don't believe a cat back exhaust system was enough to out pull an M5) nothing personal.

 

An 03 M5? Why not? If his intake tract was all nice and cool and the starting point favored the gearing on the Jag it's more than probable.
Maybe the M5 missed a shift too ... ;>))

Such silly sh*t.

 

play nice fellas. Take this thread somewhere else, or see it locked.

 

I think you misunderstand.

 

Ok guys, let's take it easy. For the sake of clarity, I mentioned in my post that the pull was from 75 mph on, not from a dead stop. At this juncture gearing played less of a role as both machines were well into a similar power band. Even if we went at it from a dead stop I'm confident that my well "exhausted" and more powerful STR (est. 425 hp @ 435 lb/ft trq., est. 4.8 sec. 0-60) would have equalled if not out pulled the 03 M5 (394 hp @ 368 lb/ft trq 4.9 sec. 0-60) from a dead stop. I've read it here; those who've had their ECU's tuned saw higher trans.shift points. I've related this in a recent post that since the full exhaust mod and a hard re-set of the ECU, DSC off and trans. in SPORT mode, I've been successful in teaching adaptive learning to perform a 5500 rpm 1st to 2nd shift and 6250 rpm 2nd to 3rd. If we go back to earlier threads, Riski was able to do this only after his full exhaust mod., 3 lb. pulley install, and ECU hard-reset, not before. As for the "...stock exhaust manifolds (headers) ?, they are perfect for the job. Chris of Mina Galleries dissected the STR's power plant and reports; the STR's exhaust manifolds are small, angled down, and designed with low restriction in mind. Steel tube Headers may in fact hinder performance in the lower parts of the powerband. Many of us here most likely noticed on our other/former street machines; the stock manifolds allowed the engine to maintain higher low end torque, whilst the addition of headers were only of value during late mid to top end pulls. What I write next is strictly meant to be informative: Brian, if you haven't performed a full exhaust mod. and your desire is to open up a whole new chapter in your STR's performance potential, then I'd recommnend a full exhaust mod. I'm sure you'll be more than pleased with the results. Coupled with your already installed 1.5 pulley, a full exhaust mod will likely allow your STR to belt out an est. 450 hp @ 470 lb/ft trq. Imagine what an ECU dyno-tune could do thereafter?.. maybe 475 hp and 500 lb/ft trq)? Do an ECU hard-reset, teach her a hard driving style and see what happens. The 1.5 pullley goes on my STR this week. I was going to save this for a new thread: Last night on the way home I sheepishly pulled up to a white 4-door 2004 MB 55 Kompressor (470 hp, 525 lb/ft trq.), lowered with blacked out wheels. I knew I didn't have a chance (unless I possesed a twin screw and tuning, lol!), so I just watched this "thing" take off as if a humongous rubber band pulled it...seamingly effortless brutal acceleration with a low authoritive exhaust note. Only by the time I came out of my mesmerization did I remember to hit the gas. On the way home I couldn't stop thinking about how friggin fast that MB clicked off a 0-60...just mind boggling quickness.

 

So I went over to the body shop today to see the progress on my race car and as I was leaving a vendor came in to the shop and he notice d my STR. Well as it turns out he just bought one, same exact year etc., 2 months ago. Well I had a great drive on the way over and even though it's 95F here today when I started out the car was cold and it ran like hell all the way over. But after I'd parked for 40 minutes with lots of time for a full heak soak OMG what a difference. I thought the parking brake was stuck on or something. I can't wait for the nice fall weather.

Bob S.

 

ditto, cold air does nice things for engines.