Supercharge Or Turbo?
Q. I'm looking to take my 350Z to the next level with either a supercharger or twin- turbo setup? Which kit gets the best bang for the buck?
A. It depends on what kind of bang you're after. Some superchargers are "set it and forget it" and you only get the boost provided by the pulley. Some kits offer upgraded pulleys but they can require additional fuel upgrades.
Turbo kits are a lot more versatile and boost levels can be more easily changed. Remember that tuning electronics is the key factor in the power output and reliability of a forced-induction system. Intercooling is also a prime concern that should be considered. You may see a wide range of prices so focus on the completeness of the kit in question. Too "less" of a buck may result in a "bang" that you won't like, so remember to see the big picture.
You need to research reputable brands, determine the bang, determine the bucks, and make your move. The bottom line is the 350Z has been well figured out at this point in time, and supercharger and turbocharger kits on the market now are quite competent
Run Away
Q. I need some technical help with my '99 WRX. I have a Garrett T12 turbo and would like to know what other engine modifications I'll need to do when I put this turbo on so I can drive the car day-to-day, and give it a bit here and there without blowing my engine?
A. Run away from this turbo. It's good for a weed whacker or chainsaw, but not a lawn mower and certainly not an EJ20. This is the smallest turbo Garrett makes. It's for limited motorcycle applications or engines competing in mpg testing. It maxes out at 130 hp.
We aren't sure if you're from Japan, Australia, or someplace where the WRX was offered in 1999 or if you have an Impreza and are converting it to turbo duty here in the states. Suspecting the latter, we suggest a turbo conversion kit that delivers all the hardware you need. Turbo Specialties has a T25-based kit designed for '98 to '03 Imprezas. It includes the manifold, an FMIC and related piping, numerous turbo system components, and an electronic injection control unit. The kit has optional upgrades to a ball bearing T25 or a ball bearing T28. We suggest the T28 because you'd have more wiggle room for a future boost up.
You'll need to address the fuel system by adding a bigger fuel pump, upgraded injectors, and most critically, a tuning scenario that ties it all together to ensure you'll realize the full potential of the conversion. Be sure the supplied fuel enrichment strategy is up to the task. If you have any doubts find a setup you're more confident in.
Drop My Corolla
Q. I roll a five-speed '85 Corolla GTS. I want to drop the car and enhance the handling but am really confused when it comes to spring rates, and how they translate into performance on the street and at autocross events. Can you help me clear the air about this?
A. For prudent street lowering, Eibach Pro Kit lowering springs fit the bill. They deliver moderate lowering and a small bump in handling. From there, it's either expensive coilovers or more aggressive springs. For comparison's sake there are a number of TRD front/rear combinations whose specs can also be used in a coilover setup.
Your intended usage will play a big part in dictating which combo will work best in your Hachi Roku and this is mere ballpark banter, not an end-all guide to spring rates. If the car's a weekend warrior that will see commuter action during the workweek we'd go for a 7kg/5.7kg setup. This one will provide good ride quality and enough firmness for autocrossing. Going with an 8kg/6kg combination may challenge the kidneys if you're sensitive but still be acceptable on the road, while rising to the occasion when the helmet and driving gloves go on. From here we're heading into race-only rates. Both 10kg/8kg and 12kg/10kg combinations are for high-speed road circuits or drifting.
You're wise to be wary. There's a lot riding on your decision (sorry about that) and you really need to figure what is more important: street ride or performance handling. We highly suggest erring on the ride side.