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10 minutes ago, GTSBoy said:

Because....2 different sized turbos implies a sequential system. An inexperienced hobbyist setting up a sequential system from scratch sounds like hilarity. Toyota and Mazda spent millions on their systems and never really got it right.

So, I'll assume you're not doing a sequential system. I'll also assume you're not doing a true compound system, seeing as the turbos appear to be planned to be on opposite sides of the engine. And also because low boost and high boost numbers quoted appear to be about 1/4 of the values that you'd expect for compound.

So, maybe just two stage compression? In which case, the GT30 is mahoosivley oversized. Either that or the GT42 is. Well, at least one side of each of them, probably.

So, then I make a sensible suggestion of binning the additional turbo and putting an original M90 supercharger back into the Ecotec system and properly twincharge it. This actually makes a lot of sense because it will do what you suggest (fill the torque hole caused by the GT42) but.....if proper sequential is out of the question, then proper twincharging is also probably out of the question.

And all of those thoughts went through my mind prior to posting my first response, and it all seemed too hard, so I just copped out and made the post I did.

Yeah all good but on my setup the gt30 will hit full boost by 2-2500 till 5-5500 that's where the gt42 will come in at about 4-4500

Does a gt30 run off 1.9L worth of exhause make that much air flow for a 3.8L engine that quickly? You could be reallly showing some guys how its done if you pull this off.

Way back in the day people did run v6 turbos with only one bank providing the exhaust flow, no idea how well that worked, and they didnt use another larger turbo in the mix like your plan has.

how does that budget breakdown? including TH400 and converter or not?

 

1 minute ago, Ben C34 said:

Does a gt30 run off 1.9L worth of exhause make that much air flow for a 3.8L engine that quickly? You could be reallly showing some guys how its done if you pull this off.

 

A gt30 is good turbo choice on a stock mildly worked 1.8l civic so what's it gonna do on a 3.8l with fair amount of mods to it that balance top end and bottom end? Very quick response and good top end

1 minute ago, Bessel said:

A gt30 is good turbo choice on a stock mildly worked 1.8l civic so what's it gonna do on a 3.8l with fair amount of mods to it that balance top end and bottom end? Very quick response and good top end

well sort of,the 1.8 engine puts out 1.8l of exhaust and consumes 1.8l of air, .

I  like your confidence. full boost at 2000rpm will do skids nicely

14 minutes ago, Ben C34 said:

well sort of,the 1.8 engine puts out 1.8l of exhaust and consumes 1.8l of air, .

I  like your confidence. full boost at 2000rpm will do skids nicely

Oh yeah my cousins auto f6 bf typhoon 420rwkw with full boost at 2000rpm constantly wrestles the traction control system from any speed around or below 50/60 till 140

Edited by Bessel
23 minutes ago, Ben C34 said:

Does a gt30 run off 1.9L worth of exhause make that much air flow for a 3.8L engine that quickly? You could be reallly showing some guys how its done if you pull this off.

Way back in the day people did run v6 turbos with only one bank providing the exhaust flow, no idea how well that worked, and they didnt use another larger turbo in the mix like your plan has.

how does that budget breakdown? including TH400 and converter or not?

 

Plus it’s not the turbo setup you have that’s as important as the n/a setup ->> shit n/a setup+good turbo setup= shit running car (regardless of the goodish tune)/ good n/a setup+shit turbo setup= shit running car/ good turbo and n/a setups= lambo killer

30 minutes ago, Bessel said:

Yeah all good but on my setup the gt30 will hit full boost by 2-2500 till 5-5500 that's where the gt42 will come in at about 4-4500

 

23 minutes ago, Bessel said:

A gt30 is good turbo choice on a stock mildly worked 1.8l civic so what's it gonna do on a 3.8l with fair amount of mods to it that balance top end and bottom end? Very quick response and good top end

 

I don't get it. Is it your plan to have both your turbos connected up to both exhaust manifolds? As in, the existing crossover pipe is still there, you're just hanging the GT30 off the same exhaust supply as the GT42? In that case, you are wrong about how it will work. You will to be lucky to spool either turbo, because each one will just be a bloody big wastegate for the other one!

If your plan is to have the GT30 just running from only one bank, while the GT42 is running off the other bank, with both boosting into the same inlet system, then you are in for a different version of shit. The GT30 will then indeed be boosted by a 1.9L engine (a pretty shitty 1.9L engine though, not making as much flow as 1.8L of Honda). But that bank of the engine will be receiving the same boost as the other bank, whilst having a much tighter exhaust flow path. So the two halves of the engine won't be making anywhere near the same power.

And, if you plan to have all sorts of exhaust and/or boost switchover valving to try to make it work, then you're back in the Toyota/Mazda sequential world I was talking about, and I wish you luck.

Also don't forget the nos, 2 of the big ones. The ford boys will be frothing.

I love a good moo mang and this sounds like it's gonna be awesome and drop epic sick skids. Please upload skid vids when done. We love skids around here.

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