M20 2.7i turbo. Need advice... a lot of it.

[timmyr77]

Hey there. So I already posted a thread on here asking about if port and polish is worth it. Got my answer. And I figured since I have never dealt with a boosting a car, I need all the advice I can get.
Money isn't the biggest issue, (planning about 1500 on the head, and another 1-2k on the turbo set up? sounds reasonable?) since this build will be slow and I can save money pretty easily. I know what I will be doing with the engine, but as far as the turbo goes, i just have a general idea of what I want.
(fyi its going in a 87 vert)
So, for the engine, I've planned to have
IE heavy duty rocker arms,
Oversized eccentrics
Stainless steel valves
Double Valve Springs
APR head struts
Performance Head Gasket ( haven't decided on which)
MS2
and either a IE272 camshaft, ( or was also suggested a z45 282 cam, but seemed like a bit overkill for me)
and of course a 2.7 block with super eta pistons and rods

So thats what I have for the engine. now as far as the turbo set up goes, I don't have much clue of what to get.
I dont know turbo's whatsoever. All I know is I don't want to run much boost. Most likely no more then 18psi and hp goals are around 350-400.
Im willing to go for less power if it means more reliable since this will be my dd.

So Im open to all the wisdom I can get.
Thanks Tim

[ANDRÜ]

Holset turbos from Cummins are very popular, and perfect for that much boost, since the trucks run about that. HX35s are everywhere too

[timmyr77]

well they seem to be pretty cheap. ill put it down on the list for possible turbos

[1owNslo]

+1 on holset... everyone on here so far has suggested i too go with holset for my turbo set up. they are rebuildable and aren't crazy expensive either. so thats another thing to keep in mind (service, amd maintenance vs cost)

[squidmaster]

The earlier model "e" has the lowest compression ratio piston/rod combo. Holset is popular and cheap and reliable and powerful option. The hx35 is the most popular and reasonable. Just keep in mind that "hx35w" models will come with an internal wastegate that has too high a psi setting for many engines. So try to find an external wastegate option.

Or you can go with a subaru turbo. Good mid-range turbos like the vf10 or vf40. Can be had for cheap, and the wastegate is generally 7-12psi. though some are 14, so do your research.

[pantelones]

Read... If you have not already.

http://www.e30tech.com/forum/showthread.php?t=74816

And please do not run a N/A cam. If your going to replace the stock cam (honestly, stick with it..), get a reground one through MR 325 or custom cam from someone else AFTER you have your set up complied and everything is set in place. The tuning will be way easier, and it will make the difference between having to run 11psi or 18psi to achieve your power goals. Also, since you stated that this is going to be DD I would recommend getting a twin-scroll turbo. I used to have a list of turbos that would work well with the m20, but I abandon that ship a long time ago when the reality of how much it is going to cost to make a good quality, and RELIABLE turbo set up. Best of luck, not trying to Debbie-down you, but just be realistic...

[timmyr77]

Seems like everyone suggests hx35. But I was hoping for something that kicks in earlier. Like I said I'm will to go for less power. Especially since its a dd

[timmyr77]

Also was thinking about twin scroll and seems like it is the best way to go for reliability

[squidmaster]

Seems like everyone suggests hx35. But I was hoping for something that kicks in earlier. Like I said I'm will to go for less power. Especially since its a dd

I recommended the Subaru turbos. a lot earlier peak boost than the holsets.

Also was thinking about twin scroll and seems like it is the best way to go for reliability

but much more costly.

[timmyr77]

I'll do some research on the Subaru turbos. I'm willing to spend more to have it right. I don't want something that licks in at 3-4 rpm. And the waste hate being 12 or 14 psi is fine I guess if I have the cam regained right.

[timmyr77]

Regrinded*

[squidmaster]

for the Subaru turbos you'd have to modify the air-outlet. they have a specific connection that isn't just a generic circle though. just thought about that.

[Chriskbmx]

when it comes to cars you have to pick 2 out of the 3 goals. cheap, fast, reliable. that is where my goals would start. Also Reliability comes down to, good management, with a good tune, good turbo, good waist gate, and a good blow off valve. Also make sure you go with a wideband o2 sensor. Its a great way to monitor whats going on. I also forgot make sure that the oil system for the turbo is done right.

[timmyr77]

Well I chose fast and reliable, since I said money isn't the issur

[TheTacoMan]

Well I chose fast and reliable, since I said money isn't the issur

I cant help but notice, your location.

Best of luck.