Tuning a compound charged car with megasquirt?
 

Hey guys. A lot of guys told me to check out this forum. Never thought I had to until I hit a roadblock. Yes I am a bit of a noob but I am here to learn from you guys.

The car
1990 Volvo 740
16v motor with a Holset H1c
Megasquirt n spark(EDIS)

My car is mid build at the moment. I have had "builders block" with my latest issue. My turbo is a Holset H1c. It has a 21cm exhaust housing on it. Big, too big. Some people use the block off plate to block one scroll. Some people perfected it further and allowed the other side of the scroll to open once boost hits(learned that here ;)).

Well I bought a M62 blower hoping to use that to spool the turbo. Is it the best idea? No. I could buy a better sized turbo, or block a scroll, or to be completely lag free use a blower. BUT I am doing this partly to be different. I have become determined to use this 21cm housing.

Now from what I understand an o2 sensor is affected by the amount of oxygen that passes by it. If I blow clean atmosphere air into my turbine, and out my exhaust, will this throw my AFR readings off? I have NOT tuned much before. I am a noob. But believe me, there is not much to read about tuning a compound charged car.

This has been done before. How so? Best choice? Thanks for the help.

Re: Tuning a compound charged car with megasquirt?
 

you are gonna blow the outlet air from your blower through the turbine in addition to the exhaust, yeah hope that works out for ya :1

Re: Tuning a compound charged car with megasquirt?
 

reversion and pressure difference owns :S

Re: Tuning a compound charged car with megasquirt?
 

You know more than me. Like I said, how is my idea wrong and how would I fix it? Blow through the compressor housing? Will the holset have issues drawing through a blower?

I have never got to see this setup. Probably never will due to the rarity. We talked on the Volvo board about TT. A small stock T3 and a holset. Nobody really knew, but it was assumed the holset would have a hell of a time making boost through a T3.

Re: Tuning a compound charged car with megasquirt?
 

I could tell you what I was going to do.

But then you'd have the car I want. With the setup I want.

So no.

Re: Tuning a compound charged car with megasquirt?
 

spill the beans amigo :8
come on...

Re: Tuning a compound charged car with megasquirt?
 

for one thing what you said is not doable, learn the correct terms for what you want to do and then get back to us, i think you want to run a twin charged setup. it has been done befor and is done on like all detroit 2 stroke diesels.
learn what a turbine is, what you said is you want to have your blower running into the hotside of the turbo? what?

Re: Tuning a compound charged car with megasquirt?
 

You can do that as well.

But I would run a smaller turbo and a bigger turbo on the same manifold. Smaller turbo spools until it becomes a restriction, by which point the larger turbo is already moving and that will keep it going all the way to the top.

Only problem I can see is the added heat from the smaller turbo still flowing some amount of air, but the majority of the charge would take the path of least resistance.

Re: Tuning a compound charged car with megasquirt?
 

Its got nothing to do with knowing the lingo man. I knew what I said. If you read what I said, you would have understood that. Again, I asked if the added oxygen in the exhaust would throw my O2 sensor for a loop. O2 sensors are effected by the passing oxygen in the exhaust. By added clean atmosphere air to the exhaust, is that going to throw off my AFRs.

I meant what I said. If you don't know the answer to my ----, just sit back and read along with me. Don't hate on me. ::)

wafflesincars come on man help me out. PM me if that helps lol.

Re: Tuning a compound charged car with megasquirt?
 

Exhaust leaks are notorious for ------- up your o2 sensor reading,ect. I would'nt run an m62. 50% compressor efficiency and weaksause. If I was looking for low end power with some room up top, I would phase in a larger turbo from a smaller one with some sort of wastgate/flapper device than run that.