Discussion in 'SVT Tech Forum' started by JL_Tampa, Oct 16, 2004.
what are you shifting at
Another very good question. Shifting too early can knock off at least a couple MPH.
right around 6000
5800 was too low
and 6200 seemed to lose power
I admit I need more seat time as this is my first 4.6L
I think the car will go 8's as-is
And it does need to be dyno tuned very soon 95000miles on it
Shift the car at 7k on the 1-2 and 2-3. On the 3-4 shift at 6600-6800. When you shift higher it puts you in the meat of the powerband for the next gear. With 4.10's and nittos you should be mid 13's. Run the nittos between 16-18psi depending on the track prep. I pulled consistant 1.7's with 17" nittos. Remember 4v's love to rev, so twist that motor. -Mark
WOW dude, those shift points are WAY off! I admit that it feels like power falls flat after 6200rpm, but I got my best trap speed by redlining every gear.
Next time, bring her to 6800rpm on every shift, I can almost gaurentee your trap will shoot up ~2-4mph.
Do what I did, get some 4:30's and some ticky tires.
My best has been a 13.88 @ 100 or so; more typical is 14.0-14.10 @ the same mph. Have yet to get a 60' time under 2.0, even with the Nitto's.
It seems the problem for me has been not getting the tires hot enough; my last time at the track I held the burnout for longer than I normally would, & the car hooked & bogged.
Launching this car has been a struggle for me; my next attempt will be at FFW on the 13th/14th.
Combo: all stock except Flowmaster 2 chambers, MAC cai, Top Line shifter, H&R street springs, & 245/45 Nitto drags.
Like most have said, 6000rpm is way to low to be shifting at. Run her up to a 200rpm's short of red line & powershift. With those improvements, you should easily crack the 13sec mark @100+mph.
I have very similar mods on my 98 Vert and I hit a 13.2 at 104mph at a track at nearly 3000 feet altitude with 3:73's.
Got 4:30's not but I haven't been to the track. I'm looking for 12's easy NA on DR's now.
I also think it would be a very good idea to take a look at IMRC's on this car. With a 60' like that it sounds like it's running flatter in the higher revs than it should. If they have never been cleaned it's a good chance that they’re clogged on this car killing its high end power.
Well he admitted he was shifting at 5800rpm. That will KILL his ET and MPH. I bet he could squeeze another 4mph out of it by redlining it and nailing every shift.
I only have CAI, and Nitto DR's (17 x 275) and have hit 13.2x fairly consistantly. Like others have stated a good launch is huge. I have have hit 1.8x 60 ft. just about every time I break 13.30.
I try to have 12 - 14 psi in the tires, need to have the nittos plenty warm too. I try to drop at 5K, with those wide nitto's i can generally get a good hook. Power shift right at the redline the whole way.
I have left more than a couple inexperienced '03+ Cobra owners scratching their heads. I have never beat one, officially. They tend to beat me on the big end, but I get out clean and quick and they really have to get that monster moving to catch up.
I beat my clutch up pretty bad recently so I am gonna need to address that this winter, again =/ I'll be lucky to break 14 with the shape its in now.