A question about desciptions of turbos

I would like to learn a little regarding the
different terms I hear used when describing
a turbo, eg..K27-7200,KKK, Garret Hybrid. Is the KKK a brand name? Any help sorting this out would be helpful.

KKK is a brand as is Garrett AiResearch. Most American cars in the 80's (Mustang SVO, T-Bird Turbo Coupe, Dodge Daytona, etc.) used Garretts. The design is very similar. There are some flow capacity numbers (i.e. .63) that make a lot of difference when you set one up for non-production applications. Not being sure where you want to go with your turbo question, I’ll take the liberty of sharing a little of my experience… None of this stuff is really rocket science, but building a production engine not designed for this application with a turbocharger or supercharger is not too far down that scale. That’s because it is pretty much the reverse of all the things we teach other about making horsepower in conventional engines. Turbo engines use lower compression FORGED pistons (8.1:1 is a good starting point) to compensate for the “pressurized” effect created with the compressor (opposite of what we want for a hotrod P-car engine (non-turbo). Also critical is the strength of the existing engine…if the engine has miles on it, then it is important to resize the rods, new bearings, magnaflux everything, high volume oil pump…on and on. A loose rule of thumb is 1 lb. of boost is roughly equal to 10 horsepower. So, you can image what stresses can be put on internal components when you get up to say 15 lbs. of boost in an engine not expecting that. It’s expensive, ugly, and short-lived. On the other hand, drivability is pretty docile when you’re not spooled up and fuel efficiency isn’t necessarily negatively affected. I built a rather nasty 2.3 liter 4-banger turbo Ford engine in the early 90’s and have some of the specs on theory around somewhere if you’re interested. There is a link to a photo from my turbo project below. Please forgive the moray effect as this is a scan from a photo from an issue of SuperFord March 92’. This engine used a large (approx. 500 cfm) 2 bbl from a 429 family sedan-type engine, mounted directly in front of the Garrett .63 breathing through an air cleaner from an early Buick turbo (see left-hand side of photo in the link). The head had Motorsport oversize valves (as in 351 Cleveland) and many other tricks. I wouldn’t go that far again. I (irresponsibly) ran 107 octane leaded VP fuel and 15-18 lbs. of boost (octane is the liberator of detonation…which is the death of turbo pistons). The seat of the pants was exhilarating, but the brakes were anemic and I got out of it just in time. Great fun while it lasted.

There are kits form some of these applications…they’re expensive and sometimes don’t deliver the punch due to the stress on non-turbo designed engines. The whistle of the compressor spooling up is sweet though whether your sideways with tire smoke or not!

http://members.aol.com/aprmca/porsche/2-3l_ford.jpg

Jack McAllister