What is under your decklid?

[Erich Wagner]

Lot of nice Engines.
Specially Rod's cars are just my taste. OUTLAW. Does anyone use 48 IDA's on a 356 Engine in a Speedster? I am finishing my "Very - big bore" 356 Engine in few days and bought 48 IDA's. The next step is to "create" my own Intakes. I want to make them as long as possible and want to use Airstacks like Greg's. (very nice!) Spedsters have not that much space to the Decklid....?? The question is can i make the Intakes longer than 5 inches....4 inches?

Please post pictures if you drive a IDA equiped 356 Engine in your Speedster.

Thanks,
eric

P.S: Sorry for my poor English...

[Bruce Baker]

Lot of nice Engines.
Specially Rod's cars are just my taste. OUTLAW. Does anyone use 48 IDA's on a 356 Engine in a Speedster?
eric

Eric, I bought an S90 Roadster in the early 1970s that had 48 IDA Weber carbs adapted to the 'big' Solex manifolds. I am sorry to say that I have no pictures to share, but I remember the performance was terrible until the upper UPMs and then suddenly it was.....ZING-G-G-G!...over red line and floating the valves!

I am sure the beauty of those carbs can be saved by venturis (Luftrichters) and jets that are suitable to a larger than stock displacement engine and others may know this, I do not...sorry.

Good luck!

[C J Murray]

The problem with using 48IDAs is that there is a sweet spot relationship between the size of the butterfly bore and the size of the venturi bore of around 80% plus or minus. When you get too far from that there are issues with drivability. Additionally you would need to increase the bore of the intake manifold by 8mm which will kill intake gas speed and also ruin drivability. To get real good street driving results I would think that the engine would need to be larger than 2000cc to use those carbs.

[C J Murray]

Really long intake runners should boost torque but will hurt top end where your big carbs will start to work. It won't know what to do. You could try to make a long tapered intake manifold that keeps a stock port size and then use the smallest possible venturi. An 1883cc street engine works well with IDF44s with 34 or 36mm venturies.

[Erich Wagner]

You are both right.
Engine displacement has to be at least 2000ccm. My special 356 Engine "creation" will be even bigger than 2100ccm. So the gas speed should be ok. I want to start with 40mm Venturis. I changed really very much on my heads to fit 47mm intake valves (changed the angle of the valves a.s.o....) If this Engine is ever spitting fire it will be a "Funnycar".

Seems that i have to start measuring in my engine compartment 8)

@Bruce: Maybe you remember me. We met at Hersheys Swapmeet at the stand from Adam Wright.

All the Best,
eric

[Aki Ruohonen]

Hi,

Drilling a 3rd progression hole to IDAs is common modification in VW world and it does help the transition area. In large engines transition area works better even without modification but with small engines this should help even more. There are plenty of sites describing the procedure in detail, here is one: http://www.vintagerotaries.org/index.php?showtopic=28

Erich, your planned powerplant sounds really interesting - would it be possible to get more information on that?

Aki

[C J Murray]

Erich- I hope you are building a track only drag racer. You are definitely going the "bigger is better" route.

I would be grateful if you would post pictures of your modified cylinder heads. I would like to see the angle change and how the 47mm intake fits. By the way, what size exhaust valve were you able to fit with the big intake?

Thanks
Cliff

[Jack Roberta]

Here's mine...

[Erich Wagner]

Thanks Aki for the Link. I think i will let the carbs as they are. I always can drill the third hole if my engine is spitting because of to less fuel.

No sir, i don't build a track only engine. Here in Austria we have plenty of "curly" roads without police 8) and our goverment closed most of our circuits here in Austria because of protests of the residents and the enviroment....bla bla bla.... so i HAVE to race on public roads

This will be a "street race" engine with the target of minimum 200NM ~ 150ftlbs and around 155-160 hp.

We are still welding and things change daily. (Learning by welding...) I will post some information on the "356 in Austria, Garage pics" thread.
Feel free to add comments on this thread.

http://porsche356registry.org/356talk/4 ... ml?start=0


All the best,
eric

[Bill Sargent]

Coming soon - shot of the 4 cam cooling unit that will be on my 1883 cc pushrod motor. Hoping to start assembly in a few weeks. Cooling unit is on a dummy motor at Ibrahim's shop. I guess it will be called a faux cam motor. Eventually it will be in my 59 cab GT project.

[ron goodman]

fuel injection with in house electronic system

[Freddy Rabbat]

mine:

[Greg Banfill]

Tight fit....

210+ hp 2332cc with IDA's on Super Flow heads.

Sheet metal / cooling is still in the works.

[mike southard]

Here's mine ... 2002cc twin plug

[Frederic Prince]

choice of Stacks or Filter

fred ©