So this is my dilemma. I am definitely going to put on Kooks LTH and go E85 this spring. I also have the Boss mani sitting here waiting to be sent to 01bluesnake to get ported. My dilemma is should I just stick with the LTH/E85 and swap the mani for a 1 piece DS? Will adding the Boss to the LTH/E85 hurt my 3K-5K HP & TQ enough to offset the 6.5K to 7.3K gain? Would the DS be a better option? I know that the Boss will probably bring my lower end in line to with what I have now before the LTH/E85 mods. The reason I choose to go LTH and E85 was to gain back the midrange. Just now wondering if the gain would better without the Boss. I do track the car about 4-6 times a year and at Road America I do top out 5[SUP]th[/SUP] gear so I’m basically coasting once I reach 6.5K RPM. I’m currently looking to see if I can find Dyno comparisons of a LTH to Boss setup.
Boss Mani or 1 Piece DS??
- Thread starter devildog1679
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Porting, LTs, and gears... Yeah.. You'll offset the loss... The boss mani torque loss is so hyped up to be a absolutely terrible thing but when you're racing, it makes a world of difference. The power band shifts; and instead of dying off where the stock manifold does, it just keeps on going. Besides, you're up at the top of your RPM range when you're racing. If the boss mani was that terrible, why don't boss owners switch to 5.0 manis? You'll be happy with results
If you do end up bailing on the mani for the DS you should sell that mani to a fellow Wisconsinite!
The driveshaft will offer you advantages of weight savings and rev and decel way more than the manifolds power gains will ever do
Yea, it would be nice not to have the car fall flat on its's face at Road America at the end of every straight. I just don't track it that often. Maybe 4-6 times a year. Wonder if the extra HP&TQ in the mid range without the Boss but with the DS will be a better compromise.
Good to know, I also have the Boss strut, black covers, and install kit.
True just not sure how well they hold up at 140+ mph. Doign some research on them now.
Why do you say that? I have a Shaftmasters that has regularly seen 130mph 3RD gear pulls and plenty of guys run them at 200+mph in Tx Mile
Read some post back when I first started modding my car about vibrations. Many people say they went 130 with no issues but my car will see repeated 145 mph runs at the track. Things could be different know. Just so many options.
I have 3.73s, and I'd never go back to the stock IM after installing my ported Boss. I don't know about the higher geared cars, but as quick as mine revs, I don't miss the 15ish torque that I lost around 4000RPM. Increasing the operating range from 3500-7000RPM to 3500-8000RPM helps a lot with the low gears. The DS is a good choice too, but I'd say that since you already have the IM, do it now and get a DS next time around.
Yea, tough choice. Ah, I need more $$ lol
lol,
the trick with the boss mani is you really have to wring it out n/a to take advantage of it.
they look sweet though.
let me know if we can help you out with an axle exchange or dss d/s
the trick with the boss mani is you really have to wring it out n/a to take advantage of it.
they look sweet though.
let me know if we can help you out with an axle exchange or dss d/s
I had a vibration when I first went one-piece but we changed the pinion angle by adjusting the upper and I have been over 160mph with zero vibrations on my shaftmasters
I am not a fan of the ones that use a adapter at all.
Driveshaft is a waste of money unless you're doing it for safety reasons IMO
I'd do the mani
I'd do the mani
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7000-7200 is about the optimal shift point on the stock IM.
I once believed that too...
What are your results?
Keeping the revs above 5000 is what should be best according to the power curve.
Keeping the revs above 5000 is what should be best according to the power curve.
On track shifting at 7K gets you back into the meat of the next gear. Downside is that from 6.5-7K your acceleration goes down.
I might just do the LTH & E85 then Dyno and drive for a week. Then I'll add the Boss mani drive and Dyno and see which i like best.
did you get a chance to dyno it yet? I'm also contemplating a boss mani atm
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