Although its not a Magna, this could help some of you guys who want to put a larger bore throttle on your magna.

I cut out some 5mm plate I picked up from a local metal shop, and hole sawed a 50mm hole in the middle of my two flanged. Tapped some thread in the big one and drilled some holes in the smaller plenum side. Then attached the two with the a piece of 2"(50mm) pipe. Then I chewed out the port on the plenum and fitted it all together.

I used epoxy steel to seal off the un-used idle control valve openings(removed ICV from TB) and had a few un-used sensor holes in the plenum alloy welded closed to make everything look legit.

http://turbocharade.com/images/G200t/throttlebody-50mm-adapter/

The same idea could easily be used to fit a MUCH larger throttle to a Magna plenum. Im thinking 80mm Falcon TB's :)

Im yet to fit the plenum, but will update with results.

The original TB was 34mm, as its from the austrian released NA EFI version of my motor. No EFI versions were released over here so I imported a handful of manifolds and injection setups.

must say.. nice work

yeah agreed, u most get so much satisfaction out of ur charade knowing uve done all this stuff urself ..

it would be a lil harder doing this with the magnas though yeah ? with the MAS and all?

yeah agreed, u most get so much satisfaction out of ur charade knowing uve done all this stuff urself ..

it would be a lil harder doing this with the magnas though yeah ? with the MAS and all?

Can't see the magna MAS/MAF sensor being an issue. I think the reason not many magna owners have gone down a this path so they could fit a different / billet throttle body is that most people don't want to loose their cruise control :bowrofl: .

I know I don't want to loose my cruise, and will be glad to retain it.

Also, going to a bigger (80mm for example) throttle body would probably be overkill for all but the most hardcore N/A Magna engine.

I know I don't want to loose my cruise, and will be glad to retain it.

.
in that example would it really be that hard to use the falcons cruise control?? from what little i know cruise aint the hardest feature, was going to put the cc from the gto onto my car but the conversion took too long.

Top work tc

Thanks guys.

If I had a 3L or 3.5L, the first thing I would do is install an aftermarket ECU, so the MAF problem would be nonexistant :D

There is also not really any point on upgrading a throttle on a lightly modified motor, but in some cases I've seen on here it would be a nice addition to the other mods, if the MAF could be sorted or a decient ECU was being run.

Cruise is a closed loop system remember, it will compensate for a larger/different throttle so long as everything still links up and attaches. Making the linkages suit the CC would be the big drama, I removed a handful of linkages and solinoids from my TB as they are all controlled by the haltech and mounted elsewhere.

Hey all, if i could just add to this, if you do undertake an excercise like this, make sure the inlet manifold is off the car. I know it just seems like common sense, but i have seen some dodgy things in my time.

I've just installed a 60mm throttlebody on my car (was 50mm stock). I have enough room on the inlet manifold flange to machine it out to 60mm, but that was the max that the stock manifold could be machined. If i want to go any bigger later, I will either have to make up one of these adaptors (which i'd rather not . . . personally i see it as moving the restriction), go custom, or invest in an RPW performer manifold.

That was my spare manifold Narkus, I did the work while still being able to drive the car when needed.

I have fit it, and I cant say there was an astounding difference :( I was hoping for earlier spool up and a bit more peak. Peak power doesn't drop off for another few hundred rpm which I noticed straight away, and spool up MAY have increase a little but nothing of much consequence until I get to the track and see how it goes out of corners.

I did notice that with the larger valve, I only need 1/2 the throttle to do what I used to, so if I were a stupid man and continued to use the old amount of throttle to drive, I would think the car has a lot more balls.

WOT vs WOT its about the same but I am still glad I did it because now the Haltech drives the idle control via PWM and it sits at a lovely 1000rpm :badgrin: