justin

Has anybody done this?
I am wondering if it will make more power at all? I know that some of the guys with 944's do this with success. Any imput? I am running a straight exhaust with two resinators, headers soon to follow, just thinking about letting her breath a little better.

the flyin' scotsman

I did it on carbs for a race bike..............boring the t.body was easy compared to trying to tune it for 1/2 the season.

I now own a selection of pilot jets, slides, needles and main jets to fill a complete box...........all from HRC.

Not saying it can't be done but the headaches..........ouch.

Funn944

check out bigborethrottlebodies.com

mark kibort

there is not enough meat on the stock throttle body. better just try and find a euro throttle body.

mk

justin

Thanks guys, Mark I was afraid of that.

ceedee

and how much are they?

danglerb

On a fuel injected car the throttle body is just a big valve, no jet issues, just stuff like making it open linearly, flow what you want, and not mess up the air stream for your metering device. On many cars it is a restrictor plate with much to be gained from a larger unit. How big is it anyway?

scott863

I think it's 2" and the euro are 3" I know I'm wrong on the exact numbers, but I think the euro has a larger opening by 33-50% over the USA one for the pre '84 cars.

SMTCapeCod

I had my Euro throttle body bored out. It was a "while I'm at it" project, didn't anticipate much in the way of gains. Made other changes at the same time, so I can't say whether or not there was an actual improvement. Consensus at the time seemed to be that extrude honing the intake (if you have a spare grand or so) and getting headwork done would be more productive in terms of increasing flow.

GRTWHT

Hi guys, does anyone know what size throttle I have on my '81 928 4.5L Auto car?
Vin Number begins with 'ZZZ'

Thanks
Glenn

gruffalo

I'm sad to say that you probably have the small one, if it's an M28/10. I am dismantling an engine just like that in my garage as we speek, just for fun.

Jerome Craig

BTDT: What a pain in the a$$! I did it on a '76 280Z. I immediately went from 21 mpg to 8 mpg! It took months and some serious $$$$ to get everything right. Afterwards, the car ran like a scalded dog.... but I almost went nuts and broke trying to get it to run right. Just changing the TB is simple. Getting the car to perform correctly - if ever - is a challenge.

My $0.02

GRTWHT

Yes the engine number begins with M28/10.
Has anyone placed the larger one on a 4.5L engine and had and benifits?
I dont think my engine will ever reach redline at 6250RPM.
Also are the larger ones easily obtainable? Will the bolt on to the standard mounting place?

Regards,
Glenn.

danglerb

Carbs are crazy tuned flow aerosol things, fuel injection is a pipe the computer sprays gas into the end of. Airflow through the metering device is important, the tuned pipes down to the head are important, everything else its just about flow.

For around 300 rwhp 70 mm is good, thats what just short of 3"?

Can Euro S parts still be purchased from Porsche?

I wouldn't expect anything to fit, but wouldn't expect it to be impossible to make it fit. Buy a bigger throttle body, and bore out other parts as best you can. How big is the metering thing?

Ian928

Here is a picture of my 928 Euro S TB: http://www.flickr.com/photos/2196736...7594052999722/

Ian in Norway