Improving your IDA´s...

[JS]

To be honest, I had some of the first ones made, the "pin" that centers the in the groove of the carb body was about 0,2mm too long and I had to spend a few seconds filing them down to make them fit more easily. That "snag" has long since been corrected.

For strip results, read further back in this thread. It's good entertainment, thrust me! 

As for the stacks they flow about 1-2cfm more than stock, so not really. What I have understood about stacks it's not all about flow but also about the design of the stack. They should be pretty straight and have a curve at the top of the stack. This is to help the pulse "turn" at the top of the stack. I'm not sure stacks that looks like a wide "V" in profile helps that in the same way(They look cool though). Many F-1 engines have straight walls it seems.

Jaycee claims on his website that his stacks alone improves flow by 21cfm. I'm not sure how that's possible(A 42mm JPM venturie gains 19cfm over a normal 42mm). This is gained by getting rid of the secondary venturie that's "in the way" of the airflow. Likewise, the small increase in flow on JPM stacks comes from them being a little larger inside diameter compared to original ones, not the shape as such. You will of course need to tune the total stack-to-valve inlet lenght regardless of what system you go for.

I am really out of my depth discussing these design details, but I think they are very interesting and hope that the more experienced engine designers of this great forum can chime in and give their opinions! 

[Torben Alstrup]

This year has been a laying low season for most of the serius racers around here due a healthy mix of lack of time, lack of funds and damaged machinery.
I am however certain that "we" will come back strong in 2013. And also provide some back to back power data regarding these upgrades.

But, like I menthioned way earlier in this thread, this upgrade does not deal with peak performance alone, but just as important to make the IDA carb work better on the street. The few, apart from the man himself, that have tried them on the track consistenly reports a drop in ET of 1 to 2,5/10´s along with the butt feel of better pick up power. What that relates to in HP I do not know. your guess is as good as mine. But if we relate to the increase in carb flow alone, then 19-21 CFM improovement should equal about 5 hp as a rule of thumb. The closer you get to the max performance of the carb the better numbers. So whhen the time comes I´m sure we will see power gains ranging from a few hp to about 10 hp.

T

[1950split]

JS and Torben, thanks for your input.

The fact that these venturies not only improve the top end rpm range but provide something across the rpm range makes them an interesting addition.

As for the stacks, I guess I'll keep the original ones for the time being.

[Eddie DVK]

A small question, hope somebody knows this.
When I visited Johannes on my way to SCC this summer, he was testing some JPM venturies in Weber 45 DCOE carbs,
but is he thinking off making those venturies also for 44 IDF's or 45DRLA's carbs?

Regards Edgar

[Torben Alstrup]

I know he is. I do think that it is mainly a question of getting the time to develop them, - and need for it. The day he has his back against the wall in a certain combo, they´ll get developed. That´s the curse of being a one man army.

T

[Eddie DVK]

Ok thank u Torben.
I will wait patiently 

Regards Edgar

[wolfswest]

Does anybody have more info/updates already?  Back to back tests?  I really want to know more because I'm willing to try a set.  Do I need bigger jets or just swap the venturies?


Thx,

Dem

[Basti]

So here is finally my report.
I meassured my 2,1 Typ 1 yesterday on the dyno.
The engine has 51,5 IDas and a compression of 15:1 running on race fuel.

With standard venturies 44mm and Jaycee intakes it was 245 hp.

With JPM venturies 44 mm and intakes it was 262 hp.

I use 170 main jets normally in i ended up with 175 with the jpm venturies.

Both versions were tested 3 times on the same dyno witout take the car of or something else. the runs
were in between 2 hours....

So a very interesting result!

See the dynosheet attached!

Cheers,
Basti

[JS]

Congratulations on awesome dyno results!!

The percentage hp gain from the venturies is along the lines we estimated on my old engine. Cool to see it documented!!

[Jesse/DVK]

Good results!

[BeetleBug]

Almost 125hp/l - VERY nice! I look forward to reading OC1967vw comments after this.

-BB-

[leec]

Very interesting result
So the jpm vents and 'intakes' added 17BHP, what do you mean by 'intakes?'

Lee

[Tobi/DFL]

He meant velocity stacks by JPM.

Tobi

[leec]

That's amazing, new vents and stacks equals 17BHP

Lee

[Matty c]

Almost 125hp/l - VERY nice! I look forward to reading OC1967vw comments after this.

-BB-

 

[andy54]

i have a set of the 42mm jpm vents and the jpm stacks going on a 2276 ida motor when its finished. looking forward to what its going to be like does anyone know if they will help all round driving on the street???


cheers andy

[Old Guy]

Basti,

Thank you.  Those are very very impressive results!  The gains are right in the RPM range many drag VWs operate in.  Johannes should expect a large increase in orders shortly.  (Including from the U.S.!)

Ron Barrett

[chez2165]

Does he have these advertised on his website as I could be interested in a set.

[NoBars]

That's what I have been waiting to see, I am going to try a set of them. I wonder how much cfm loss there will be with a set of the CB billet stacks.

[JS]

Does he have these advertised on his website as I could be interested in a set.

http://jpmotorsports.se/ms/ms/j-p-motorsport-nya-produkter/ms-90000825-p-3/

[BeetleBug]

i have a set of the 42mm jpm vents and the jpm stacks going on a 2276 ida motor when its finished. looking forward to what its going to be like does anyone know if they will help all round driving on the street???

cheers andy

With regards using them on the street, please take a look at the curve again and pay attention to the range from 2500 rpms up to 3500 rpms. This is the area where you cruise and where many experience issues (dead spot/hesitation) With the JPM parts you gain almost 20hp in this area (from approx 62-63hp to almost 80hp). You are looking at a improvement of around 30% in the most critical range for street driving.

-BB-

[Basti]

i have a set of the 42mm jpm vents and the jpm stacks going on a 2276 ida motor when its finished. looking forward to what its going to be like does anyone know if they will help all round driving on the street???

cheers andy

With regards using them on the street, please take a look at the curve again and pay attention to the range from 2500 rpms up to 3500 rpms. This is the area where you cruise and where many experience issues (dead spot/hesitation) With the JPM parts you gain almost 20hp in this area (from approx 62-63hp to almost 80hp). You are looking at a improvement of around 30% in the most critical range for street driving.

-BB-

Hi BB,

i think the curve in this area doesn´t show the exact values and isn´t comparable as this is a full race engine
which is not running smooth and perfect in this area under full load.
So i can´t say anything regarding street drivealbility difference, sorry.

Cheers,
Basti

[BeetleBug]

Hi BB,

i think the curve in this area doesn´t show the exact values and isn´t comparable as this is a full race engine
which is not running smooth and perfect in this area under full load.
So i can´t say anything regarding street drivealbility difference, sorry.

Cheers,
Basti

I understand what you are saying.... writing... and of course you`re right. Far more important than the actual increase is the curve.

[Old Guy]

That's what I have been waiting to see, I am going to try a set of them. I wonder how much cfm loss there will be with a set of the CB billet stacks.

Anthony,
I would use both his vents and stacks just like Basti did.  Your setup is very similar to ours and I would be very interested in the results.  I would dyno your engine with the current setup (48IDA's I believe w/42 vents), then 51.5s W/44 vents, (Joe would probably lend you a set) jet the 51.5's for the best HP and then install the new 44 vents and stacks on the 51.5s.

You might even want to try some 44 vents in your current carburetors first.  I think there is a couple of more horsepower available there.  That way you'll know whether you want to order 44s or 42s.

Ron Barrett

[Jussifin]

We have used those JPM parts in rally now 2 seasons and the engine has been much better. Now we put those also into 1400cc Mini circuitrace car with one  48 IDA> got 4hp + 15nm more in dyno at once and runs much better on driving...Cheap developing in racing

Jussi

[NoBars]

No polished parts from JPM... The upside is that the finish is so good that polishing should not require too much work.
I believe the price is 2995 SEK for the vents and 2195 SEK for the stacks. That should include 25% Swedish VAT.

It took a while, the anodizing used leaves a pretty rough surface when stripped. I sanded them on my lathe to get the surface close to finished. 

An unanodized option would be nice. they look great polished though.

[NoBars]

pics

[Old Guy]

Beautiful Anthony.  Are those the 48's or 51.5's?  Can't wait to see your dyno and track results.

[NoBars]

Just 48s. I see a trip to Jaycee in these carbs future.

I dont know that they will be Dynoed anytime soon, I will tune them with an O2 sensor at the track.

[Old Guy]

Anthony,

Did you get the 42 or 44 vents?  Good luck at he track and let us know what improvements you find. 

Ron