Re: divided exhaust housing flapper valve.. quick spool down low, big power up top?
 

I seem to recall VNT turbos having problems in gas engines due to higher EGTs. If you look at factory cars there are very few factory gas cars with a VNT turbo while a lot of diesels have VNTs. Although, there are a lot more turbo diesels than turbo gassers.

The only VNT gas car I can think of off the top of my head is the very late 16v shelby turbos in the lazer and such.

Re: divided exhaust housing flapper valve.. quick spool down low, big power up top?
 

You're joking, right? Think you can rig an electric actuator to a Vgt just like that? Good luck figuring that one out. And, talk about one more delicate and expensive thing that would break.

Whereas this is a simple and cheap solution for those of us who have Holsets or other turbos with huge ass turbine housings.

Re: divided exhaust housing flapper valve.. quick spool down low, big power up top?
 

+1, thats what hmt is all about

Re: divided exhaust housing flapper valve.. quick spool down low, big power up top?
 

^^^ i wouldn't consider $699 cheap for this thing. :-\

Re: divided exhaust housing flapper valve.. quick spool down low, big power up top?
 

Yeah for sure that's waaay overpriced. I'm talking of a diy version here.
For one thing, it doesn't at all need to be stainless - can all be done in mild steel, imo. Or just the flap in stainless to keep it thin. Get a used wg actuator, a hobbs switch and you're set. Shouldn't be more than $150 in materials, maybe even $100 or less.

Re: divided exhaust housing flapper valve.. quick spool down low, big power up top?
 

those same materials could be used to experiment with vein technology.....a little time studying pulse width circuits and you could make a controller for the turbo even cheaper and much more precise. I dont think with the big back housing on the he351 that egt's would be as much of an issue. I also recall reading and article in maximum boost about their usage etc. Everything seems promising what i see about them, thers a guy right on here using one on a DSM currently. So yes it can be done, and their purpose is to get into boost quick and then open up for higher flow as the revs increase. Isnt that the basic idea all you guys wanted from this flapper?

Im not telling you what to do or what you should do to your car im simply stating what i think would be a better option. If you want a flapper use a flapper, i wont loose sleep over it.

Re: divided exhaust housing flapper valve.. quick spool down low, big power up top?
 

i was talking about hmt, diy is a different category


and I had a interesting idea about this and my build. i've been looking for an autocross setup insetead of drag strip. I was willing to sacrafice some top end to gain quick spool time. I know this is what the valve is all about, so here is another option if someone had one of these.

autocross = valve fully closed all the time. drag strip = full open for traction control or have it set up where the valve switches over if you can put the power to the ground. i of course see the need for two different tunes, but they couldn't vary by much.

I personally think the flapper style that the guy did on the maxima is the easiest to setup. it would possibly flow better as well with the flapper guiding the exhaust into the single scroll. but whatever, thats my 0.02

Re: divided exhaust housing flapper valve.. quick spool down low, big power up top?
 

I see your point also, just different strokes for different folks :)

Re: divided exhaust housing flapper valve.. quick spool down low, big power up top?
 

I think I can make if for the cost of just the 1/2' flange. I am willing to bet everyone here has a Tb that there not using; and a internal wg there not using. Does anyone see what I am getting at?

Re: divided exhaust housing flapper valve.. quick spool down low, big power up t
 

I already asked weird about a flange.. he said just weld 2 together.. also the butterfly plate would melt, wouldn't it?