Pi
I can see you're not interested in upgrading the brakes. Okkkkkkkkkk....
The point of buying used PI heads when you already own a set escapes me. Just remove the ones you have and have them machined.
As for used cams, again, you already have a pair of those in your car. If you're talking about picking up a pair of used aftermarket (comp, crane, crowder, etc) cams, I'd be careful doing this. If you end up having them reground its going to cost just about the same (used cams + machine work) as a nice new pair of cams. If you KNOW the used cams are correct for your application and in great shape, sure, go for it. If the cams are a lot stronger than stock, you MUST replace the springs with a set that matches the cams, and replacing the retainers at the same time just makes common sense. Old springs with strong cam = valve float (and worse).
$2000 will not get you a new supercharger, and I'm leary of used units unless you know how to check the clearances and have knowledge of the source. CNC job on the heads + new cams + new valve springs, etc. will be right at $2000 if you don't have to buy any labor.
Superchargers are best installed by experienced mechanics, mostly because of the tuning needed. Most good dyno shops will quote you upwards of $500 for the tune, by the way. Superchargers can be tricky to get right, and its not unknown for the installation to require multiple upgrades to such things as fuel pumps, fuel injectors, air/fuel mixture settings, spark plugs, etc, before they run reliably. Failure to do this can result in detonation, and inevitable death for the motor.
As for bang for the buck, the usual rule is:
Gears. Depending on your intended use (street/strip, etc), you'll get the most pop from gear upgrades IF you're not going with a positive-displacement (eaton or twin screw) supercharger. 3.73's will work well with everything except the aforementioned kenny bell, while 4.10's probably do best at the strip with a naturally aspirated car. As you can see, deciding what to do about gears FOLLOWS the decision of what to do about power-adders. Budget about $250 - $300 for parts.
If it were mine, I'd bank the $2000 and start saving the other $2500 I'd need to put a blower on the car. I've got some very expensive mods on my car that will be hitting the parts bin as soon as I put the supercharger on - not all mods play well with their peers. Things like gears, underdrive pulleys, cold air systems and custome tuners often don't match supercharger installations and are a waste of money in the end. Don't repeat me mistakes - you'll regret blowing big $ on bits that end up sitting on the shelf.
Also, avoid "upgrades" that cost a lot but add little horsepower. The only exhaust item that is cost-efficient on our cars (imo) is an x pipe. You'll get 10 or 12 hp from one, and its a simple swap that will yield a louder exhaust and cost about $200 - $350 (depending on whether or not you need cats) for parts. After cat systems add only a horse or two, and cost more than the x pipe. Shorty headers also add very little power, while long tubes WILL add some power but at a high price and only with matching X-pipe replacement at the same time. Long tubes usually cut down on ground clearance, too, and if you plan to lower the car, keep this in mind.
I see nothing wrong with the VorTech products, though I personally prefer the torque production curves on the Saleen and KB twin screw units. The centrifugal items like the VorTech and ProCharger behave similar to a turbocharger - including the low end lag between application of throttle and their power-adding ability which arrives around 3500 rpm and then is REALLY felt above 4500 rpm. The positive displacement sc's start adding power immediately, though they run out of steam at high rpms compared to the turbos and centrifugal sc's.
Again, I don't recommend used superchargers - there's more to a good kit than just the super. Complete kits include EVERYTHING needed and all matching - new injectors, fuel pump or fuel pump booster, brackets, belts, lines, hardware, tuner or chip, etc. Buying used I'd expect most of this to be suspect or missing.
There are some things I would buy used - but superchargers aren't on my list. Too many folks buy these things, slap them on their cars, and fail to take the time to properly tune the rig. Boom. Now there's a destroyed motor, and they're hoping they can salvage something from the ruins by selling somebody those "almost new" supercharger components. Odds are that the same disastor that wiped out the motor took its toll on the supercharger, too. Modern power-adders are as efficient as they are due to close tolerances for things like turbines and bearings....
Modular Powerhouse installs vortech units for around $3700 as I recall - you might contact them and see what is included in this. I suspect it is about as cheap as you can go with a new unit installed by professionals.
tripleblack
MattKelley02GT said:
So lets say that i bought a used cam, heads, but bought new springs. Would it be a bad idea to buy the heads used? Also, installing is no big problem with me, because i have a family friend that will install for free. If i was to spend a total of 2K on the total setup, would you just recommend a supercharger? I know i would have gotten some 3.73s for my next mod after the engine mods, but if i decide not to do the heads, can i get a decent used supercharger for around 2000-2200? I also know the the twin screw (KB) are the most desireable supercahrgers because of the amount of the low end torque. What about the vortech superchargers with different trims ie. V2, VSsq, A trim etc... can i get a differnt type of supercharger that isnt as highly rated ? Im kind of confusing myself haha. i just need hlep
