the X factor in duplicating the STS system is the oil - turn the way back machine to when i was prototyping my chevelle for the truck, that was the concern i was having and was doing some digging on how to create a stand alone oil system...about a year or so later STS was born and had the universal kit with the same oil pump i was looking at using, but the still used the same oil used in the engine...
long story short, yup, i can duplicate....
lemme try to address each question...
1 - Exactly how would a turbo V8 act in day to day driving?
well, i guess it depends on the driver, but from what experiences i have had, it acts just like it did before the turbo with a bit of a kick when you want it. in some cases it acts like a bigger motor - imagine uphill at part throttle, it will get into boost a bit and climb the hill faster at the same throttle position. it will be easier to pass and you will actually
find yourself using less of the throttle because you have more power on tap...
2 - What sort of fuel economy would I be able to expect during normal driving?
again, it depends on driving style, how much city/highway, but in my truck (for example) i actually saw an increase in mileage - not much, and i didnt really have enough time with the turbos to verify all the info, but i did get better, and even better when i switched to E85 - which goes against what everybody says.... there was 1 tank i remember getting an extra 75 miles from E85 compared to straight gas. again, i didnt have enough time to get solid numbers, but overall turbos got me slightly better mileage and i did not change my driving style so i am confident in saying that you could see 1-3mpg improvement and worse case stay the same, the only way it could go down is if you get too happy with the new found power and cant keep your foot out of it, or go on a towing spree...
3 - How would it handle towing for distance, like more than an hour nonstop?
with a remote mount system, thats actually better for towing than an under hood system. remote mount is all by its lonesome under the bed with plenty of air movement to help with keeping things cool - not that you really want that as velocity goes up with heat and expansion, but in a towing environment, with constant demand - the turbo would be working all the time and you would need good manifolds if underhood to prevent cracking - but with the remote mount, temps stay under control.
a did a bit of towing, for more than 1 hour and even in the engine bay, they did not overheat, but did get hot - to the point where i was looking at maybe some GNX style side vents to let the heat out. but, remote mount, you dont have to worry so much about the heat issues or protecting parts and is actually less money in the long run.
i dont think there is a towing issue with the remote mount systems.
4 - What all would I need, and what could I expect the price to be, ballpark?
thats a big question and has many answers depending on sources and the like...
as far as what you need, heres the basics of what i would get to have a reliable system..
1 - turbo (of course) - this is the biggest expense and the most critical choice here. i dont have my compressor maps handy - they are all on my hard drive at home, but i would be looking at something in the T4 class and larger. you dont NEED a ball bearing turbo, but price and efficiency go up with one.
2 - intercooler - this is where bigger is usually better. you would want the largest you could fit. the sole purpose of the heat exchanger is to get your charge air temps as close to ambient as possible. this is where you either get creative or shell out the money, you can take several cores and weld them together (quite common) or find something that fits from some type of diesel setup (also common) or you best out the tape measure and get either a universal core with end caps, a universal intercooler, or have one custom made..
i had a diesel intercooler i was playing with (but i discovered how hard it is to modify) , i ended up with an ebay special - i think it was one of those 24/12/3???? anyway, i spent roughly 150 on it, all my tubing was exhaust pipe which saved a lot of money compared to the "custom" crap i could find. i ordered my mandrel "U" bends from JCWhitney as well as the straight pipe and went to town with a chop saw....
3 - you would need an oil system for the turbo. the easiest way is to do how STS did and tap into engine oil supply. the oil pump information is also on my other drive, i want to say it was in the 2-300 dollar range (been too long since i looked). it was the exact same one STS uses with out the label. has a very good life expectancy. the other option would be a stand alone oil system, which would add to the cost but in my eyes better for the engine and turbo itself as the turbo would not see the dirty oil from the engine and vise versa. with that system you would need a tank that holds about 1 gallon of oil (because its easy to get anywhere and simplifies oil change as well as adequate capacity) i would recommend 3 oil pumps (redundancy as well as a pusher pump), you would need a cooler - i would think a typical oil cooler with a fan would fit the bill, and your gauges and pressure sensor - BUT - see how this starts to get complicated? yes, there are benefits, but it starts to make things more complicated and no so street friendly.....
stick to using the engine oil and you will be fine.
BOTTOM LINE - you could put this system together for roughly the cost of a used supercharger if you shop thrifty, but the reality is most likely in the 2-3k range. i was lucky with mine, my first setup i did for less than 500 bucks, most in part to a lot of used stuff that did not have much life left in it, or any where near proper for what i wanted - but it worked well enough to get me hooked on turbos, and when i mashed the pedal and lost sight of the road because my hood became the horizon....well, the rest, they say, is history....
now, the nice thing about the remote mount system, you can still have headers and a cam - and contrary to what people say - with the remote mount, you dont have to be so picky as to cam choice, you can actually go with a SC cam and get excellent results. the turbo cam profiles are based on close mounted turbos where the exhaust back pressure is so high that it will force its way back in through the open valve - with the remote, you have less pressure because of the added volume of pipe.
so, you can still keep the things you have for it, which in turn will help it - not only on the performance end, but in the mileage department as well...
20mpg is a highway number - and if i can do it on 32's or whatever those tall tires i had were, with 4.10s, and 75mph - it is possible, but is a highway number. i was averaging 16 before turbos and almost 18 after, and a SOLID 18 with E85 (which still baffles the hell outta me)...oh - and i had more psi as well i saw 12psi spikes, but it was a steady 10psi if memory serves, my fuel system was maxed out, im sure, but the 4.8 as wiggle room my 305 never had.....i would also like to note - my 305 liked more timing than my 350 - never did get a chance to play with that theory as the oil pump went in the 305 - but i still believe the 305 with the smaller chambers is less likely to be prone to detonation than the 350 - my only proof is the fact that i was running 10psi with a wicked advance curve on cat piss gas with no knock - remove turbos, swap in 350 with same tune and knocked on 93 octane.......had to pull 10* of timing to get the 350 to act right, never did get a chance to run the turbos on that motor.....
all this info is just that - info. can be modified on all points and argued to death (which i welcome, thats how i learned the stuff i know)
if anybody would like to add, please do - i know JamesB has been doing some research on turbos and his info is pretty fresh in his brain - would be great to see some other responses and theories - or facts, whatever.
i know Lextech has a lot of practical application information, including frame twisting
ok, im done with my book....
