Larger throttle body

[VR-04-TT]

Just thought I'd share some pics of the larger TB swap I started on sunday.

It'd be all back together if I had a way of cleaning the plenum at home, but I've had to give it to my old man who has a whole stack of different parts washing bays at his work.

Here's some pics for now, I'll have finished product ones tomorrow.

Larger is on the left, stock is on the right:

Old on top, sitting inside larger on the bottom:

Gasket difference:

And the area that had to be filed out:

The new gasket sits perfectly over the new honed out hole. To be honest I'm not expecting any gains over stock (maybe a small increase in throttle response), it'll probably come into play later on with better intercooler piping and other mods.

Tomorrow night it's teach some kids guitar and then straight into fitting it all back together and resetting the TPS and going for a burl to make sure I haven't forgotten a very important bolt somewhere

PS: I finally got off my butt to do it Gly!!

 

[bratwurst_boy]

nice work paul how did you makeit larger, hone out a spare TB or modify a different one???

 

[VR-04-TT]

I bought the TB off Gly, it's from a naturally aspirated 6A13 SOHC (I think). It's a straight bolt on, just have to widen the plenum opening.

The plenum was done with a kick-arse drill and a stack of those flappy sanding discs. I went through about four of them lol.

 

[Davezj]

would a 6A13 SOHC plenum chamber not fitted the DOHC inlet manifold to make it a perfect match.

I don't know this just a thought for the future.

 

[VR-04-TT]

I don't know either. I'd guess it would fit but they're hard to come by in Oz, as the 6A13 wasn't used in much (if anything at all). Plus the SOHC one doesn't look as nice

 

[bradc]

The SOHC one is a different shape designed to optimise airflow in an N/A engine. It may or may not fit, and it may or may not increase power, we simply don't know!

 

[VR-04-TT]

It's all installed. I just have to fine tune the TPS, idle speed and put the bracket that guides the hose into the throttle body back in. I ran out of time (and energy) at 1am this morning and just ran a piece of hose temporarily.

 

[Guest]

good stuff, another happy customer

 

[Guest]

it will make a difference at stock. throttle responce and a tiny more top end power.. well thats what i felt..

 

[jungle]

I'd be interested to see how it goes. But i think you won't notice anything but if you do i bet it'll go backwards with regards to throttle response. What are the IDs (internal diameter) for both?

What other engine mods do you have Paul?

Finally what are we looking at in that final pic? Is the change in colour where you've ground put the plenum to the same size as the throttle body?

 

[VR-04-TT]

None yet, I'm not expecting any gains on the stock motor. I've done it so in the future I don't need to do anything more in this area. I expect any gains will be more in the high end than anything low end. From past experience most of these breathing mods rob from the low and give to the high end.

I've only driven it with the TPS out of whack (way out lol). So I can't say if any difference was noticed as I had to grandma it to work and back. I'm setting it properly tonight.

In the last pic, the darker area is what I had to cut out to match the new TB yeah.

I'll let you know how I go

 

[frozen]

hmm whats involved with the TPS (eg. where is it, how do you set it, how do you check its even set right?) cause when i done my plugs i might have moded some stuff around... would like to be sure its all right

 

[Guest]

interested in selling your stock TB paul?

i want to get rid of my TCL TB...

 

[VR-04-TT]

hmm whats involved with the TPS (eg. where is it, how do you set it, how do you check its even set right?) cause when i done my plugs i might have moded some stuff around... would like to be sure its all right

There's two ways, both posted here. I tried the mitsi service manual way that I posted and I had a hard time finding the spot with 0 continuity. So I tried the way Carsten showed me and I could either get one or the other, but not both.

But I realised this morning when I first woke up (seems to be when these things come to me lol) that I could probably set the WOT resistance and then just adjust the fixed SAS screw to reach the closed throttle resistance setting. If any of the more experienced guys here know any better, please let me know lol

Oh also, I scabbed piece of hose from my old man's work and it looks like it was too old (it was in the bin out the back) and it's split. So I'm losing coolant, not heaps but still not good. So I'll be fixing that over the weekend.

If you do the swap you'll need to get a longer hose that goes from the water pump to the TB.

Mitchy, I prefer to keep the old part just in case anything goes wrong and I need to revert back to stock (and I'll have to buy another plenum!). If it all stays good later on I'll think about it You have first dibs in that case

 

[VR-04-TT]

Well I tried both ways of setting the TPS and I think I may have it ok now. It just still doesn't seem quite 'right'. But other than that the car is running fine The hose wasn't split...I was an idiot and forgot a hose clamp *slaps forehead*

Now to report on the TB:

On the stock car there's no point (this was completely expected as I said earlier), throttle response has probably gone back a step as per jungle's prediction. I can't be 100% sure as the seat-of-the-pants meter is never 100%.

Overall I think you'd need to be running much higher boost to get any benefit from it. I don't forsee myself doing any major turbo swaps in the future so I may revert back to stock when I find a plenum.

If you're wondering "why'd you do it if you're considering going back to stock?" well...people talk a lot about mods and what happens on forums, I like to get my hands dirty and find out for myself what happens. It's more costly and can be frustrating, but at the end of the day I know what the result is and I can happily pass on the info as first-hand experience.

I may consider a plenum swap or selling my setup if anyone is interested who's running higher boost levels etc.

Oh mitchy, I found a few stock throttle bodies on importmonster, pm me for links

 

[bradc]

I think you'll find that in fact you can be 80% sure that the seat of the pants o meter is at least 70% correct, but never 100% always 100% correct

 

[jungle]

Hey Paul what the ID of the TB?

Dis regard, i found it.

Not to be pain in the butt see my response here http://ozvr4.com/forums/showpost.php?p=22939&postcount=20

 

[bradc]

60 vs 64mm I beleive

 

[Guest]

59mm vs 67mm


this is the larger one....

http://www.ozvr4.com/forums/showpost.php?p=22679&postcount=67

this is the smaller one

http://www.ozvr4.com/forums/showpost.php?p=22693&postcount=68

its a worth while upgrade IMO... with tuning and supporting mods

 

[VR-04-TT]

Hey Paul what the ID of the TB?

Dis regard, i found it.

Not to be pain in the butt see my response here http://ozvr4.com/forums/showpost.php?p=22939&postcount=20

Not a pain at all mate. As I said, I just wanted to know what the difference would be for myself.