questions about turbo
 

I have a 2.3L in a Ranger with a 5 speed. It has about 300,000 mile on it but still runs good, no smoking or weird sound from the engine but I'm going to have it machined and put forged pistons in to hold up with the turbo. I am looking for a turbo that will build power down low say around 1,500 rpm's and pull to about 4,000 rpm's, really more like 3,500 rpm's. I am not looking for a fire breather, but rather a real torque monster. I was thinking of boosting around 15 psi. Also, I know most turbo'd builds are low compression but I was thinking of going 10:1 compression, to help power before the boost starts but to also help spool up, don't know if this helps but have read that it does. The next thing I would need is a tuner to re-flash my ECU. What is the most popular tuner people use? I think I have a pretty good idea of what to do and what parts I need but would rather post here and see.

So
Turbo with internal waste gate
Simple Mild Steel (sch 40 pipe) header
3" turbo back exhaust
Ported head with Inconel exhaust valves, milled
Forged Pistons
Intercooler
42# injectors
255 lph pump
engine bored .030" over with 2.5L crank
tuner
misc. parts (recirculation valves, etc.)

So what would be a comparable turbo to a stock SVO turbo like the IHI?

Is it possible to run 10:1 CR with 15 psi boost with a good tune?

Is it possible to reach full boost at low rpm's i.e 1500 rpms?

I am only shooting for 250HP and maybe 275 ft. lbs. torque but would like it around 3,000 rpm's

I have come to learn the turbo is dollar per hp the cheapest mod for the 2.3L. Thanks

Can't help you with everything but:

10:1 and 15psi boost? Not without direct injection and computerized engine management.

Full boost at 1500 rpms? Yes, with a small enough turbo.

250 horse and 275 torque, at 3000 rpms. Never happen.

250 horse at 3000 rpms requires 438 lb/ft of torque.
275 lb/ft at 3000 rpms yields only 157 horse.

You need to spin that motor harder to make power.

Thanks for the response.

Can any one point me in the right direction as to where I can maybe learn to calculate and theorize what turbo would be a good match to what I want to achieve? Basically just want to make good amount of boost at a low rpm. It's a work truck/project truck, I don't want to have to rev the engine past 5,000 rpm's to see an increase in power. I was going to stay N/A but the more I read, turbo is going to be my best bet. Sorry for all the noob questions. Most threads I've seen is dealing with the SVO style engines that came turbo'd. I've been trying to find some specs as to what rpm range these engines peak at, turbo specs, etc., etc., but no luck. The other problem is everything is top end power, nothing really mentioned about low rpm grunt below 3,500 rpm's. I like the turbo idea because boost is load induced. If I'm running down the road and the engine isn't struggling to pull, little to no boost is present, but when the truck encounters a hill and starts to pull hard, the turbo kicks in and starts building boost. Am I being rediculous in doing a turbo for this application? The turbo is the most expensive part of the swap besides the machine work and tuner, so I want to get it right, the first time.

I am really looking for a jump in torque more so than horsepower, though I know tq is the amount of work done and hp is the speed in which it is done. Just because you can pull 50,000 lbs doesn't do any good if you can only do it at 15 mph! The stock engine makes 112 hp @4,600 rpm's and 135 ft. lbs. of torque @ 2,600 rpm's. Will the turbo increase the power output in the same rpm range or will it move it higher? That is what I am trying to get, more tq and hp but relatively close to the same power curve. I figure a turbo that can do this will not pull very long but who really drives around in traffic turning 4,600 rpm's. So if it stops building power at 3,500 rpm's, I am cool with that, I rarely go that high anyways.

I've got 4.56's in the truck right now but have a friend who will buy them from me if I decide to go to 4.10's or the original 3.73's that I had and pay me 100.00 to throw them in. I think I'll probably go 4.10's, I love the bottom end power when I take off with the trailer but I see the lady at the gas station more often since swapping. I know it's impossible for anyone to say "turbo X will reach full boost at X rpm's", I know I can put the smallest turbo on I can find and will spool as soon as I crank the truck but over spooling and heat build up will result along with a possible blown engine. I've always received good advice from this forum so this is the reason I am asking.

Another thing is I read that a general rule is 1 lb/min of boost is good for 10 hp, so does this mean that say my truck makes um... 50 hp N/A at 2,100 rpms and the turbo puts out 10 psi of boost at the same rpm, my truck will make 150 hp @ 2,100 rpm's? I'm just asking, I really don't know a thing about figuring hp with turbo's let alone turbo's in general, just trying to learn. It would be kinda funny to have the same power to weight ratio of an F-350 pulling a 30' goose neck in a Ranger pullin a utility trailer, ha ha! Figuratively speaking of course.

1980s SVO 2.3 turbo info:

http://en.wikipedia.org/wiki/Ford_Mustang_SVO
200 horse at 5000 rpms means 210 lb/ft of torque at that engine speed.

"...Am I being rediculous in doing a turbo for this application? The turbo is the most expensive part of the swap besides the machine work and tuner, so I want to get it right, the first time. ...."

Clearly it is not ridiculous to use a turbo on a small engine for light truck use. However, with your starting point, to shoot for Ecoboost power levels with your first attempt is a bit looney. Think of the R&D resources devoted to the Ecoboost engines and then compare those to your budget.

IMO for what you want, a 4.0 OHV swap would make more sense.

You can put shorty headers on it and even dump the EFI for a 4bbl set up if you want and if your vehicle is not subject to emissions inspection.

You'll have that off the line power you want and you won't be turn up much past 4500-5000 rpms.

Serving suggestion....your truck, your money, your time. Spend it wisely.

210 ft. lbs. torque @ 3,000 rpm for a 2.3 turbo, I can live with that. Thanks for help.

Looks like I'm probably going to run a T3 40 Trim turbo.

I am going to throw something in from left field.

What about a supercharger with water methanol?
You could get a supercharger with a bypass so that your
not into it all the time. The water methanol would help
with the higher compression from the higher charge pressure.

Anyway it just a thought.

Sean :-drink :-fire