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Quad throttle bodies
Posted: Tue Feb 07, 2006 5:49 pm
by yarnmx5
What does it do relative to stock injector manifold setup. How much power difference will it make for a NA (NA6 specifically) engine...any more power, if so...how much more??
Posted: Tue Feb 07, 2006 6:26 pm
by green_comet
wouldnt be much of a power difference, would have a big responce difference though.. they sound awesome to...
Posted: Wed Feb 08, 2006 9:07 am
by Matty
there was one in Vic a couple of years ago - made less power than mine. But the guy had the standard exhaust and standard cams in the thing - without at least those mods, there would be little point... can't breathe in if you can't breathe out...
Posted: Wed Feb 08, 2006 9:38 am
by Boyracer
I've had a 3 cars with quads...definately give better throttle response,as Matty said you need to do cams/head work/exhaust/computer to get the full benefit.
Posted: Wed Feb 08, 2006 11:52 am
by yarnmx5
got the mods...been told the throttle bodies are worth 10rwkw comared to standard injection manifold/system...sounds like alot
Re:
Posted: Wed Feb 08, 2006 12:02 pm
by Babalouie
yarnmx5 wrote:got the mods...been told the throttle bodies are worth 10rwkw comared to standard injection manifold/system...sounds like alot
I woulda thought that if you were still running the stock ecu, then going to a programmable ecu would gain 6rwkw (still using the single TB and manifold) and if you added quads on top of that you'd get another 5rwkw or so.
So going the whole hog in one go would get 10rwkw but only half of that gain would be due to the quads alone. That said, cars with quads that I've drĂven tend to have really great response, so I think it'll subjectively feel like a lot more than 5rwkw...esp when you factor in the chainsaw induction note it'll make

Posted: Wed Feb 08, 2006 3:55 pm
by OMY005
This is what you need.

Posted: Wed Feb 08, 2006 4:17 pm
by CT
My new quads are to be fitted to the race car later this week. Will post a pic if I can remember! Hopefully it liberates a few KWs

Re:
Posted: Wed Feb 08, 2006 4:24 pm
by Babalouie
CT wrote:My new quads are to be fitted to the race car later this week. Will post a pic if I can remember! Hopefully it liberates a few KWs

5rwkw like the Babster said

Re:
Posted: Thu Feb 09, 2006 2:02 am
by Okibi
Matty wrote:there was one in Vic a couple of years ago - made less power than mine. But the guy had the standard exhaust and standard cams in the thing - without at least those mods, there would be little point... can't breathe in if you can't breathe out...
Fernando? he appeared for one run in WA and we haven't seen him since
Can you hear the drums Fernando?
Re:
Posted: Thu Feb 09, 2006 8:37 am
by Matty
Okibi wrote:Matty wrote:there was one in Vic a couple of years ago - made less power than mine. But the guy had the standard exhaust and standard cams in the thing - without at least those mods, there would be little point... can't breathe in if you can't breathe out...
Fernando? he appeared for one run in WA and we haven't seen him since
Can you hear the drums Fernando?
That's him...
Question of Lou or anyone else who has done it - how do you go getting long trumpets to fit, with the brake booster etc in the way?
Posted: Thu Feb 09, 2006 8:43 am
by yarnmx5
I will post up the results of the hp loss by removing the QTBs. I have bought emus engine out of his race car (former car) and I have the dyno results. When I get mine dyno'ed I let people know how much diff it made. Mind you, I have loch 4-2-1 headers not 4-1 so may not rev out to 8000+ like it did before....
Posted: Thu Feb 09, 2006 9:52 am
by CT
Matty, you really can't fit long trumpets in the MX5 because of the booster. I have removed my booster, but it really doesn't liberate that much more space. Ideal runner length from inlet valve to butterfly is something liek 8 inches for my car, which is about average for some of the setups I've seen. I am using throttle plates too which are better for space. That said, I doubt my trumpets will be much longer than 60mm.
Re:
Posted: Thu Feb 09, 2006 12:06 pm
by Matty
CT wrote:Matty, you really can't fit long trumpets in the MX5 because of the booster. I have removed my booster, but it really doesn't liberate that much more space. Ideal runner length from inlet valve to butterfly is something liek 8 inches for my car, which is about average for some of the setups I've seen. I am using throttle plates too which are better for space. That said, I doubt my trumpets will be much longer than 60mm.
hmmm. I read some and did some calcs and decided that about 13" from trumpet to valve would be good... never seen reference to the best butterfly position though.
there's one car locally (james on the forum) - jap import racecar - that has a QTB manifold that angles the TBs up so the trumpets are above the master cylinder.
Of course, some nice curved trumpets could be used as well I guess.
maybe sometime (after I rebuild my engine, which will be after I win lotto at this rate) I will cut up my old manifold and investigate fitting some GSX-R throttle bodies...

Posted: Thu Feb 09, 2006 2:45 pm
by CT
Yep, 13 inches is nearly impossible in our engine bays because then you'd be fouling either the bonnet or the inner fender/shock upper mount area. If I get it sorted, I'll use a plenum on mine but I somehow doubt I'll get around to it. The ideal setup would be injectors mounted in the trumpet too but again, not this year or maybe at all with the SE coming. Actually, EFI Hardware do a carbon fibre angled trumpet, I might have to investigate.......
