Jenvey TB questions...

bj · Post by bj » Wed Jun 21, 2006 9:03 pm

jake,

1 just wondering what the benefit is of the IDA pattern vs. the IDF pattern for the TBs? i know the manifolds are different, but are there any other difference...performance wise?

2. do they make "venturies" for the TBs? that way you can go big or small? that way someone can by a 48 or 50mm and choke it down to a 40mm for a smaller engine...or will this just not work?

thanks.

bj

Wally · Post by **Wally** » Wed Jun 21, 2006 11:46 pm

I have a set of 48mm Jenvey's TB's but there are no provisions in de bore to hold a venturi. Everything can be made of course, but not sure if its really neccesary with EFI engines.
Just choose your bore diameter wisely

Walter

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Wed Jun 21, 2006 11:48 pm

What waly said.
I have yet to need anything larger than a 45mm for any engine up to 2.8L, the exception was the Mighty Spyder because it revved to 9K and wanted AIR! It used a 50mm Jenvey.

I have "Sleeved" throttle bodies before, but its not easy..

bj · Post by bj » Thu Jun 22, 2006 4:08 am

cool. i thought so, but wanted to ask. what are your thoughts on the difference between the CB Perf TBs and the Jenvey's?

they are pretty close in price, have 48mm TBs, IDF patterns, and have TPS built in.

bj

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Thu Jun 22, 2006 5:53 am

For one with the CB arrangement you have no fuel rail, and no way to attach it to the throttle body (off the shelf) as they are made for a TI that has it's injectors in the manifold. Its a lot of hassle to fit injector bosses to the manifolds and then the space in a Beetle engine bay further complicates things.

There is no comparison between the two...

Wally · Post by **Wally** » Thu Jun 22, 2006 6:12 am

The jenveys are a true top quality item. I think maybe the best availible.
However, you do need to realize a few particularities with them as well, as Jake has no doubt found out the hard way as well (like I did).
- you need to use short injectors (pica-type?) or use the spacers supplied and make a spacer for an air filter housing of about 18-20mm thick.
- the top airfilter base bolt pattern is DCOE-style, so you have to find/make K&N's with that base plate.
- you have to make/find/buy and extra fuel outlets for either side (two) because only two are supplied, which is ok in a inline-4 situation, but not for us...but if you tap everything for -AN, then its not an issue of course (I think I saw Jake does just that)

They seem to hold a considerable amount of boost as well BTW

(without any extra work done to them)

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Thu Jun 22, 2006 6:17 am

I am having some individual velocity stack/ air filters made for the TWM and Jenvey T/Bs... They should be done when I return from Lemans..

The air filter quandry with ALL the throttle bodies is a pain in the ass, conventional assemblies hit the fuel rails and also the bolt patterns are off..

Kinzler has the absolute best T/Bs but they are twice as expensive as the Jenveys that I really like the best..

dstar · Post by **dstar** » Thu Jun 22, 2006 6:35 am

Ummm, do you know what the purpose of a venturi is?

It is to increase the VELOCITY, so as to have a proportional
decrease in PRESSURE(i.e. a VACUUM), to suck the fuel out of the
bowl!

IN a throttle body, no venturi is need to accelerate the air, cause
there is NO BOWL in the TB!

Don

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Thu Jun 22, 2006 6:43 am

IN a throttle body, no venturi is need ... in the TB!

Unless you are cutting up a set of Italian IDAs to make T/Bs out of them...

Of course I'm only doing it to piss of the Cal-Look boys...

dstar · Post by **dstar** » Thu Jun 22, 2006 6:50 am

MASSIVE TYPE IV wrote:
Dat Dumass DSTAR wrote:IN a throttle body, no venturi is need to accelerate the air, cause there is NO BOWL in the TB!

Unless you are cutting up a set of Italian IDAs to make T/Bs out of them...

Of course I'm only doing it to piss of the Cal-Look boys...

BUWAHHAHAHHAHAHHAHAHHAHAHHA!

I dint know that BKer's read your forum Jake!?

Don

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Thu Jun 22, 2006 6:51 am

They do... In stealth mode..

Stripped66 · Post by **Stripped66** » Thu Jun 22, 2006 11:15 am

MASSIVE TYPE IV wrote:For one with the CB arrangement you have no fuel rail, and no way to attach it to the throttle body (off the shelf) as they are made for a TI that has it's injectors in the manifold. Its a lot of hassle to fit injector bosses to the manifolds and then the space in a Beetle engine bay further complicates things.

That is not true. You can buy the CB throttle-bodies with injector bosses in the TB.

There is no comparison between the two...

However, this may be true.

dudebuggy · Post by **dudebuggy** » Thu Jun 22, 2006 11:26 am

I'm planning a type IV conversion into a 66 bus for next year and really want to try doing an DYI EFi system. I'm planning on getting the DTM now because it's on sale right now and thought of picking up some other things like the Bell Crank Linkage

Which brings me to my question. I was wondeing what experience anyone has with a dual TB EFI versus a single TB plenum design with the injections on the manifold near the heads . From what I've read the the plenum design is better but I can't image how to fabricate a plenum to fit with DTM and attached the throttle cable. I've seen I few pics it looks like it's tightly pack in and most seem to have a turbo as well. I'm not planning a turbo. If a plenum design is that much better how much in power or fuel economy would you gain with a 2270 motor. I think the dual TB EFI looks way easier to do with less chance of screwing up.

Thanks for anyone that can help me get going in one direction or the other.

MASSIVE TYPE IV · Post by **MASSIVE TYPE IV** » Thu Jun 22, 2006 11:35 am

That is not true. You can buy the CB throttle-bodies with injector bosses in the TB.

The last time I called to order these I was told they were no longer available. There is also no boss on the T/B to hold the fuel rails.

I have been haunted by this scenario quite avfew times.

bj · Post by bj » Thu Jun 22, 2006 1:48 pm

would the injectors/fuel rail fit in the engine compartment if they were on the manifolds near the head?

bj