M20B27 Turbo Questions

[Andre3127]

Gents,

I have the stupid idea of turbocharging my 'b27 when I finish rebuilding the 200 head. I am well aware of the 2.7i engine but since I have a rebuilt 200 head, I want to see what potential it has since its considered junk to you guys. I have two spare heads, so no worries.

I have a few questions, and if some could be answered that would be greatly appreciate it.

1. Will my DME freak out?

2. Should I use a RRFPR?

3. What HP will stock low impedance (NOT b25) injectors support?

4. Will I experience valve float at ~5-8 psi @4800 rpm?

Thanks

https://www.instagram.com/325e_e30/?hl=en

[TobyB]

That's not a terrible idea. But I'd go aftermarket ECU, because:

1 No. But it will not fuel the engine adequately.

2 that's a very crude way of trying to add fuel. It will help, but probably not work well.

3 stock +20%, roughly.

4 unlikely. But adding 325is inners is cheap insurance.

The flapper door is pretty primitive.... more modern air measurement devices will
give much more accurate fuelling.

In my limited experience.

t

[cro_xt]

@tobyB +

[zaq123]

looked through you pictures...nice little project. Take my advise for what it is.....stop messing with it too much to make things "better", step away from youtube. Lapping, grinding, polishing etc etc. Unfortunately, there is such a thing as making things worse. You said that the head is going to the machine shop for the resurfacing. For a few extra bucks, have them prep your valves and recut seats. You want to tinker with it and lap it a few turns to check machine shop work? Nothing wrong with that if you are careful. Absolutely no need to polish any ports, gasket match anything etc. unless you got some expensive tools to do it right and monitor changes. Just trying to help...don't take it the wrong way

[Andre3127]

looked through you pictures...nice little project. Take my advise for what it is.....stop messing with it too much to make things "better", step away from youtube. Lapping, grinding, polishing etc etc. Unfortunately, there is such a thing as making things worse. You said that the head is going to the machine shop for the resurfacing. For a few extra bucks, have them prep your valves and recut seats. You want to tinker with it and lap it a few turns to check machine shop work? Nothing wrong with that if you are careful. Absolutely no need to polish any ports, gasket match anything etc. unless you got some expensive tools to do it right and monitor changes. Just trying to help...don't take it the wrong way

I completely agree with what you're saying. The head came back, I ported it (for smoothness, I didn't make them larger) and the seats cleaned up nice. I just did that because I couldn't put it back together with ridges in the ports and sharp edges in the path of airflow. I don't expect porting to help much.

The seats cleaned up nice, and there's no way I hurt anything with how little I lapped. Valve guides are in spec and I'm putting it back together shortly. I need to resurface my rocker arms and put in my replacement b27 camshaft.

This photo is a bit over exposed, but you can see how I smoothed the ports. Nothing major, probably not even worth posting, but here you go.

Andre

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[zaq123]

pretty cool. As long as you are having a good time, that's all that matters. I'm currently having a good time as well, with 90% of my car being spread out on my basement floor. Car body is still in the garage, waiting for warmer weather to be prepped and dropped of for the paint. Thought about building a car piece by piece in my basement did cross my mind :) Would be one cool center piece.

[Andre3127]

pretty cool. As long as you are having a good time, that's all that matters. I'm currently having a good time as well, with 90% of my car being spread out on my basement floor. Car body is still in the garage, waiting for warmer weather to be prepped and dropped of for the paint. Thought about building a car piece by piece in my basement did cross my mind :) Would be one cool center piece.

It's a learning experience if nothing else. Porting for flow and valve lapping won't hurt anything at the very least.

Eventually I'd like to find a 731 head and run ITB's, but that's only if I can find the head. If not, 885 turbo it is. Since I'm a machinist, I can make my own ITB setup.

I'd rather tune my m20, just because it's a factory engine for the car. 24v swaps are cheaper to make power, but I'm mostly looking for a fun car, not a fast one.

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[Andre3127]

Unrelated to the thread, but I've already rambled so I'll ramble some more. At least on my eta, I did not have to beat out the rocker shafts. There's a cam position where all the rockers are loose once you remove the locks and slide them sideways. At that point it just takes a screwdriver in the notched to gently push it out. In my case, I would not need to remove the head to change cams or rockers because the shafts don't have to be beaten from the backside.

My rocker shafts were slightly upset on the ends from the last guy pounding on it.

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