Challenger Posted June 11, 2008 Share Posted June 11, 2008 Well I was at the junkyard today and found what looked to be from a really small 4 cylinder, it was a "dual stage" throttle body. It had two butterfly valves, one smaller one that opened at low throttle levels and than the second larger one that opens up at full throttle. Anyone know what this is off of or cars that used this? I didnt have any hex keys to remove it so I left it. Might go back for it. Quote Link to comment Share on other sites More sharing options...
Six_Shooter Posted June 12, 2008 Share Posted June 12, 2008 The opening to the throttle plates kinda oval shaped? Could be early '80s VW 2.0L, from Scirocco, and other similar VWs. *edit* Looks like this? I've thought about using these as well, but have decided to make progessive linkage for dual throttle bodies if I ever feel the need for a progessive set-up. Quote Link to comment Share on other sites More sharing options...
Challenger Posted June 12, 2008 Author Share Posted June 12, 2008 Thats it! I wasnt going to use it but thought it was interesting. Quote Link to comment Share on other sites More sharing options...
zcarnut Posted June 12, 2008 Share Posted June 12, 2008 Nissan used the dual butterfly valve with progressive openings on some FI vehicles as well. Early 1980’s 200SX for example. Too small to be used on an engine larger than 2 liters. More common on the JDM Nissans. I’ve even seen it on a Fairlady Z. Quote Link to comment Share on other sites More sharing options...
Kennysgreen280zt Posted June 12, 2008 Share Posted June 12, 2008 Audi used a larger version of that throttle body on thier 5 cyl cars. If you get the one from a 20v you get a TPS mounting area. Later on, they used a way larger version (45mm/60mm maybe) on thier V8 engines. Quote Link to comment Share on other sites More sharing options...
Administrators BRAAP Posted June 12, 2008 Administrators Share Posted June 12, 2008 Ah the ole "Two barrel, mechanical secondary, MPFI! I'm sure somone can configure those TB's for vacuum secondary operation, I.e. Load sensing/controlled secondary operation. Z. Sorry, I couldn't hold that any longer fella's Now if you can get 6 of those, one for each intake port, then have the smaller primary feed a really long small diameter runner, then at a set RPM at WOT, the secondary buterfly opens up to a shorter larger runner, like the Yamaha built Taurus SHO V-6?!?!? Quote Link to comment Share on other sites More sharing options...
naviathan Posted June 12, 2008 Share Posted June 12, 2008 Interesting, I understand the performance possibilities here, but what about fuel economy? Run the smaller plate for average driving, then when you want to open it up have the second plate snap in. Quote Link to comment Share on other sites More sharing options...
Tony D Posted June 19, 2008 Share Posted June 19, 2008 The S130's with both L28E and L20E in the JDM had progressive throttle linkages/TB's with the standard mounting for the TPS. The L20's primary opening was about the size of an American Dime, while the L28's was aroudn the size of an American Nickel. The engine usually would run at cruise and up to about 3500rpms on the primary bore. So running around normally you used a lot of the throttle play---almost 3/4 of total pedal travel. Your engine vacuum signal was quite high as a result-you got better fuel economy. But cruising along the road at 3000, you touch the throttle and the tip-in of the larger bore caused a great surge of power (er...whatever you want to call it for a stocker...) compared with a similar actuation of the smaller T/B opening. It really makes driving the car nice and smooth away from a corner. I only wish I could find a way to open up the stock bodies to a larger secondary/smaller primary for cammed operation. It would give a better MAP signal in the plenum opposed to a larger 60 or 65mm T/B at all cruise and low speed operation parts of the fuel map, while the larger secondary is there for mechanical operation when you press it the rest of the way to the floor. I'm thinking JeffP would appreciate such a feature on his car nowadays...heh heh heh Quote Link to comment Share on other sites More sharing options...
johnc Posted June 19, 2008 Share Posted June 19, 2008 Just get one of these, seal the float bowls and all other passages, and you're set: Quote Link to comment Share on other sites More sharing options...
brokebolt Posted June 20, 2008 Share Posted June 20, 2008 I stripped a car once long ago with this type of TB. If memory serves me correctly the manifold is also shaped to match the "oval" TB shape vs. the round version found on the round bore TB that is on most others. I did some "light research" and again if I recall the gains is much less than a big bore TB on a round manifold flange... Quote Link to comment Share on other sites More sharing options...
Tony D Posted June 26, 2008 Share Posted June 26, 2008 All the Nissan L-Plenums are designed to have the dual-stage style T/B on them---that's why the 'egg-shaped' hole is there---it readily approximates the small and larger bores. And the L20E plenums are much smaller than the L28E's in that area. None of the L-Engine plenums I have ever seen had a 'round hole' on them, they were all egg shaped. Quote Link to comment Share on other sites More sharing options...
Daeron Posted June 30, 2008 Share Posted June 30, 2008 what US market cars might this nissan throttle body be found on? any chance we could recon some of this linkage setup you talk of, or is that a japan-only type gig? My wheels are spinning furiously over something...I think I am having an idea. Quote Link to comment Share on other sites More sharing options...
m4xwellmurd3r Posted June 30, 2008 Share Posted June 30, 2008 All the Nissan L-Plenums are designed to have the dual-stage style T/B on them---that's why the 'egg-shaped' hole is there---it readily approximates the small and larger bores.And the L20E plenums are much smaller than the L28E's in that area. None of the L-Engine plenums I have ever seen had a 'round hole' on them, they were all egg shaped. after a bit of google-fu you're RIGHT I never knew that they were egg shaped. But why are they designed like that? I've never seen a dual staged throttle body on one. Quote Link to comment Share on other sites More sharing options...
Tony D Posted June 30, 2008 Share Posted June 30, 2008 You doubted me? Go back and read the thread, and you'll find they're JDM for the most part. Doesn't make sense to make one special manifold you can only use on ONE vehicle, you make them 'common' so little bits can bolt on and change it's character. That's the way OEM's think. They may have been on other Non-US models, Cedric, Gloria, Leopard, Laurel, etc.... Anybody in the UK or India care to chime in on that one? Saudi? Saudi got conventional distributors and FOUR BARREL CARBS on the VG30 powered Hardbody Trucks (so don't laugh yourself too hard, JohnC!) Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted June 30, 2008 Share Posted June 30, 2008 You doubted me? Well they do call you Wiki... and we all know how reliable that is. Just kidding Tony. lol The principle in a variable throttle body is interesting, but I believe it would be best if you setup a throttle by wire setup with some stepper motors. You could integrate it with boost and throttle depression in your EMS to make max power, low end torque, or economy. Adding more variables has a tendency to make problems though... Quote Link to comment Share on other sites More sharing options...
datman Posted June 30, 2008 Share Posted June 30, 2008 Golf and corrado G60 engine cars have dual throttle body that has a boost bypass for the supercharger under part throttle. I think Audi used a similar one. http://is.rely.net/2-1060-10033-l-7DMh3VLglsSHH21l0EtA.jpg Quote Link to comment Share on other sites More sharing options...
Daeron Posted July 1, 2008 Share Posted July 1, 2008 Go back and read the thread, and you'll find they're JDM for the most part. .."for the most part," but what USDM vehicles might we find the Nissan TB you mentioned on? I cannot recall seeing it, but older 4-banger 200SXs aren't something I look at for throttle bodies, normally that is stanza's and 240SXs... Could an L24 maxima have one? Quote Link to comment Share on other sites More sharing options...
zcarnut Posted July 1, 2008 Share Posted July 1, 2008 ...Could an L24 maxima have one? The dual stage throttle was definitely not used on any years of the 1981-84 USA L24E Maxima. I’ll find out the exact application dates of the 200SX and re-post. Quote Link to comment Share on other sites More sharing options...
brokebolt Posted July 4, 2008 Share Posted July 4, 2008 All the Nissan L-Plenums are designed to have the dual-stage style T/B on them---that's why the 'egg-shaped' hole is there---it readily approximates the small and larger bores.And the L20E plenums are much smaller than the L28E's in that area. None of the L-Engine plenums I have ever seen had a 'round hole' on them, they were all egg shaped. "on most others...big bore TB on a round manifold flange..." I wasn't really talking about the round TB and intake manifold from the L-6 cylinder Datsun. I was more speaking towards the 240SX swap that is popular for EFI guys on an aftermarket manifold, although I seen a Weber TB once. As I stated the stock manifold is oval or "egg-shaped" as you called it. While we are on it, I seen a round log style intake manifold that looked like it was made from round stock welded together with equal length runners. Looks like that could be a performer. Seen one with a TB between cylinders 3 and 4. That too might perform. Quote Link to comment Share on other sites More sharing options...
stagefumer11 Posted July 5, 2008 Share Posted July 5, 2008 correct my jdm l28e has the dual stage thorrotle body, Not using it anyway. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.