hustler

iTrader: (6)

Dumped it off and bought a turbo?

leatherface24

iTrader: (10)

Clever

jeff_man

iTrader: (7)

just going to have to start trying things and see what works and what doesn't, i know just about all the things said will work but some will work better then others and some will make the hair drier ware out faster.

richyvrlimited

iTrader: (1)

+1

jeff_man

iTrader: (7)

detailed pics or gtfo

jeff_man

iTrader: (7)

i talked to a eaton tech, you can adjust the bypass to no close all the way with a set screw.

EvoRoadster

iTrader: (1)

Another +1 for dual throttle bodies. They have made the car a pleasure to drive again, although at the moment the interior is partially ripped out, the soft top is off and I only have the Kirky drivers seat installed along with a hardtop + lexan window. It is hella-loud without a throttlebody on the SC intake side. I am currently at 8psi with no blow-off valve and have not had any problems so far. Idle and throttle response are perfect.

BarbyCar

iTrader: (1)

https://www.miataturbo.net/supercharger-discussion-38/supercharger-dual-throttle-project-42026/

Probably more panty twist in there than you want to read but it shows how I went from not happy with duals to very happy with duals. Stuff that works and stuff that doesn't.

jeff_man

iTrader: (7)

there are 0 pic of the set up and i read that months ago and was not impressed with it.

CRAIGO

Since you asked so politely I'll post some detailed pics for you but I'll make you wait a few days

Do you want pics of everything or just the second throttle? I'm unsure as to why you even want the pics. It's pretty simple stuff.

jeff_man

iTrader: (7)

i want everything, especially how both bodies are being controlled with 1 peddle cable. figure the body on the intake is set up like stock but the one of the blower is cracked open a more to get more air into the pipes.

BarbyCar

iTrader: (1)

Early pics linked from thread post #29. I wasn't impressed with it either which is why it progressed from there.

Godless Commie put up a bunch more pics from his at https://www.miataturbo.net/supercharger-discussion-38/dual-throttle-setup-no-more-idle-issues-47978/ but you probably weren't impressed with that either.

EvoRoadster

iTrader: (1)

Godless Commie's setup is one of the more complicated ones I've seen but you are correct, the 2nd TB is adjusted until it is slightly cracked open in relation to the one in the stock location. It did take me a few days of making slight adjustments to the 2nd TBs cable length and idle screw but I have not had to touch it since. On my setup a 2nd throttle cable, throttle body and a pulley-wheel siamesed to the primary TB pulley wheel were all I needed. If you are that interested in seeing it I will put up a few pics later today.

jeff_man

iTrader: (7)

the problem i have with 2 tb is..... bov sound cool, will cost more, i don't like extra moving parts. i also really want to get a non 2 tb system working, i think there is a need for a easy add bov and mod your bypass system.

i'm going to try first putting my tb on the intake and putting my dumby on the blower then run the vac line to the blower bypass to a nipple on the intake after the tb rather then the nipple on the blower. on paper that seems that's all you should have to do if you don't care about the sound.

EvoRoadster

iTrader: (1)

I do agree with your keep it simple ethos and it sounds like an interesting approach, looking forward to hear about your results.

jeff_man

iTrader: (7)

the only reason i can think of for having a tb on the blower is sound level and with the tb on the intake you will no longer have the correct vac at the nipple on the blower to operate the bypass.

CRAIGO

Here are the photos.

Top view of dual throttle cable run, cable support that houses the tension adjustment and adjustable VTA BOV.


Tapped and bolted into the side of the OEM throttle.




The gold nut is the lock for the dual throttle cable


Cable run at front of bay


Cable run under charger unit


Second throttle on charger inlet and throttle adjustment screw



It's easy enough to balance them. You need to make sure that WOT on the intake manifold TB is WOT at the charger inlet. Idle the engine, crack the charger throttle until you hear it start to howl and then lightly back off the adjustment screw until the howl stops. Finally, ensure that the tiniest amount of throttle input is mirrored at the charger throttle.

The adjustable BOV is really quiet which is nice. I added mine as I know of an owner with the same set-up as me on a Mk1. He has sheared off all 4 of his crank pulley bolts TWICE leaving crank pulleys all over the road. He's added a BOV and it's been fine since. Think off all that air rushing back against the charger outlet when you let off the accelerator. It's not going to stall the charger (like a turbo would) but it will act as a negative force against the rotation of the crank, supercharger belt and ultimately the 4 crank pulley bolts. Don't look at a BOV as an extra component to fail on track, look at it terms of added reliability.

EvoRoadster

iTrader: (1)

Correct which is why you need to source vacuum for the bypass from another location. I found that out the hard way. On first run-up the blower got super hot due to no vacuum to the bypass.

I am however in the process of sourcing a silicone connector and BOV to relieve pressure during throttle lift. Any recommendations for type of BOV and source?

CRAIGO

I got mine from ebay UK. It does what is should do.

The Tee, clip and BOV were around £35 all in and all brand new.

jeff_man

iTrader: (7)

http://www.tialsport.com/prod_bv.htm

tial is pricey but worth it. comes with vband pipe and clamp to weld to your intake pipe.