What kind of turbo should i use/ would prefer less lag over more boost but cheap is good

internal or external wastegate

benifits of intercooler other than more power

want it simple as possible

can i run just one of my exhuast tubes to the turbo? got long tube headers

do i need electronics to control boost or can i have a wastegate that uses a vacuum line from manifold and how would i adjust how much boost i want

 

DMC, there are several folks here who will probably pop in and give you some advice. There are a few real legends here that should be able to answer each of you questions with more than you'll ever want to know.

 

You need to size the turbo based on the CFM that your engine will use under boost. Since we don't know the RPM range, your engine displacement, and the configuration (bigger valves, types of pistons, and so on) I'm not going to make a recommendation just yet.

If you want to do this the monkey way, you can ballpark the turbo size with this formula:



Internal wastegates are obviously easier to work with because they're part of the turbo housing, but externals generally are easier to control and service down the road. The usual tradeoffs.

The intercooler cools the intake charge so it's more dense, at the expense of PSI loss. Again this is a tradeoff, and the need for one (or not) depends on the boost level you will be running, as well as intake charge temperatures. I usually recommend skip the intercooler unless you have problems because it's extra plumbing that may or may not be a complication.

Then you want a nitrious bottle instead

You'd have to weld a fitting for the turbo to mount on, and plumb the intake side back to your intake manifold. Personally, I prefer to keep the exhaust headers as short as possible, and put the turbo next to, or in front of the engine if there is room. If you're turbocharging and old car, or an F-series truck, there is no shortage of room to place a turbo. Then your engine --> exhaust --> turbo length is very short, allowing quick spoolup as the exhaust is going to be hotter, closer to the heads. Also, the intake side is shorter turbo --> intake, which also helps with spool up times. The more tubing you have between the heads and the turbo, and the more tubing you have between the turbo and the intake, the longer the spoolup time will be.

There is a lot of serious, complex math involved with this if you want a "true" solution, or you can guestimate/ballpark using the monkey math above.

[quotedo i need electronics to control boost or can i have a wastegate that uses a vacuum line from manifold and how would i adjust how much boost i want[/QUOTE]

Assuming you can size things properly to get the boost you want, you can use a variable regulator to control boost. Some internal wastegates do not like this type of device, most do. External is no problem of course. You can control the variable regulator mechanically with a lever, or a ****, or with electronics. There is no shortage of either.

My old twin-turbo dodge used a small servo with a huge spring to open the wastegates, and power was applied to that servo if one or more of the following conditions were reached:

• Engine hit redline
• Intake pressure reached 25psi
• Oil pressure dropped below 10psi
• A manual override switch in the cab was pushed

Hope that gets you started.

 

The other thing I'll add about headers is if you're using the typical mild steel headers you'll find that they're going to get extremely hot, at least a bright red if not almost an orange under full boost for extended periods of roadplay. Mild steel headers typically use thin steel therefore it will crack, split, and maybe even blow out or peel apart. All of which can ruin anything near them.

Stainless endures more heat, but of course stainless has a higher cost associated with them, but if you can weld and fabricate you can bend (or section and reweld) black pipe found in most home centers. A 1.5" ID black pipe has a typical wall thickness in the 3/16" to 1/4" range, more than enough meat to not pull apart with the extremely hot exhaust flowing through.

Remember that the turbo, while it provides boost, also increases back pressure therefore increases the heat in the headers. Making them yourself isn't too bad, but like I said if you don't have access to a pipe bender, you can section the pipes easily enough and weld them together, like so:



These are probably the ugliest turbo manifolds you will ever see, however they'll work well enough for my twin turbo 500cid application. By far better than the stock cast iron manifolds for sure. Ignore the shape of the exhaust ports - I deliberately bored them undersized (with a hole saw!) so I had "meat" to grind out so I can port match them to the heads, once I'm done porting those heads.

While the manifolds were a fair amount of effort on my part, the black pipe cost me $30, the turbo flanges can be bought on ebay for $15 a pop, and the header flanges are just $4 (each) worth of flat steel 5/16" thick, about 19" long, and 3-1/2" wide I think. Nothing fancy, nothing special, commonly available materials.

By using the very thick wall black pipe welded together, along with the 5/16" thick header plates, they are strong enough to support the weight of the screaming turbos, which saves me the aggrevation of making bracketry later on. Of course this puts additional weight on the exhaust studs, but I'll be using strong ARP fasteners for that and the way I have the header plates sitting on the heads, there's quite a bit of metal of the flanges resting on the head so that will give it a lot of surface area to make a good seal, and spread the weight around a little bit.

 

Here's another picture of "in progress" homemade turbo manifolds. YOu can easily see here it's just a bunch of tubing sections welded together to form a really crude arc.

 

DMC, see what I mean?