48 IDA...short or long manifold??

[nightmair nick]

was wondering what s the difference beside clearance issues ?

[Lids]

something to do with torque and power bands.  John maher gave a very detailed reply in the racing section a while back.

http://cal-look.no/lounge/index.php/topic,8136.msg124195.html#msg124195

[Rick Meredith]

Basically longer runners make the power down lower in the RPM range and shorter runners make the power at higher RPMs.

[TexasTom]

... and short manifolds are a BITCH to do plugs ...
UNLESS you either pull the engine or take the fenders off and cut out the fenderwells.
BUT, they LOOK cool.
TxT

[Bruce]

... and short manifolds are a BITCH to do plugs ...

.... but way easier to fit air cleaners.

[Rick Meredith]

... and short manifolds are a BITCH to do plugs ...

.... but way easier to fit air cleaners.

Air Cleaners?? We don't need no stinkin' AIR CLEANERS!   

[stealth67vw]

... and short manifolds are a BITCH to do plugs ...
UNLESS you either pull the engine or take the fenders off and cut out the fenderwells.
BUT, they LOOK cool.
TxT

I don't think I've ever pulled all 4 plugs with the carbs still on the motor even with tall manifolds.

[Pierside Parts Unlimited]

No trimming of the body or deck lid is necessary. 
But good luck on the plugs. Dyno the motor before installation.  You only wan to do it once.

[Udo]

... and short manifolds are a BITCH to do plugs ...
UNLESS you either pull the engine or take the fenders off and cut out the fenderwells.
BUT, they LOOK cool.
TxT

I don't think I've ever pulled all 4 plugs with the carbs still on the motor even with tall manifolds.

If you relocate the spark plugs you can get them out :-)
Vee dub parts has some nice short ida manifolds ...
Udo

[So.Cal.Life]

   I have had both deanos and skat traks, and with the right combination of ratchets, extentions, plug sockets etc. I never found it all that difficult, I must say a bench grinder and a little common sense used to alter your tools is a considerable help, if you are using the big velocity stacks, removing #1&3 would help also....  no holes in the wheel wells.         KG           

[Bruce]

... with the right combination of ratchets, extentions, plug sockets etc. I never found it all that difficult,

  Same here.  I took a Craftsman socket and chucked it in the lathe to make it a thin wall, super short socket.  Works great.
It's not much effort to pull the carb and manifold when you need to change your plugs.  Trying to do it under the car through holes with the manifold in the way seems to me like trying to have sex with your pants on.

[JS]

I pull my carbs to change plugs. 5min off - 10min on. I use a 1/4" ratchet, 10" extender, and 10mm pipe connected to a swivel.

[Sarge]

   "I have had both deanos and skat traks, and with the right combination of ratchets, extentions, plug sockets etc. I never found it all that difficult, I must say a bench grinder and a little common sense used to alter your tools is a considerable help."  
       

Well put!  It's easy to modify a socket... use a Craftsman as it's broached the full length.  Chuck it up in a lathe and knock off 10mm or so, then use a bench grinder on the other end.  A wobbly style extension works best.

[Zach Gomulka]

Gary Berg taught me the wobbly extension is the secret to plugs/manifolds. Works a treat

[So.Cal.Life]

    Looks like Sarge got into my toolbox!!!          

[nicolas]

while on the subject of manifolds, is there a benefit in performance or use to flip the carbs. like on the gene berg manifolds you can either set them up with the fuel-inlet either in or out? why is this done?

[Bruce]

Depends on the linkage you want to use.  Center pull, or cross bar.

[Zach Gomulka]

while on the subject of manifolds, is there a benefit in performance or use to flip the carbs. like on the gene berg manifolds you can either set them up with the fuel-inlet either in or out? why is this done?

I have often wondered this. Of course there would be no difference in flow at WOT (but how often are you at WOT on a street car anyway?).  Are there differences in flow at partial throttle, depending on which side of the manifold the throttle plate opens? It would be an easy test on a flow bench with a pair of Berg manifolds.

[volkskris]

while on the subject of manifolds, is there a benefit in performance or use to flip the carbs. like on the gene berg manifolds you can either set them up with the fuel-inlet either in or out? why is this done?

I have often wondered this. Of course there would be no difference in flow at WOT (but how often are you at WOT on a street car anyway?).  Are there differences in flow at partial throttle, depending on which side of the manifold the throttle plate opens? It would be an easy test on a flow bench with a pair of Berg manifolds.

udo becker manifolds could be used too 

[Bruce]

Look at the way the throttle shafts work.  If you orient IDAs with the fuel inlet to the inside, you're using cross bar linkage.  Flip them around, you need to use center pull linkage.

[So.Cal.Life]

      Bergs  linkage works both ways. 

[nicolas]

yes the linkage can determine how they are set up, but i like to use a centerpull and have used it on the 'normal' (inlet inside) as well. in case of the IDF manifolds you have to. so i don't really see the advantage of casting a totally different manifold just because of the linkage. and like So.Cal.Life said, Bergs work both ways and it is them (as Udo) that have a manifold that can use the carbs flipped.
So i am sure there must be another reason.

[Bruce]

Bergs  linkage works both ways. 

True, but it doesn't work very well when the fuel inlets are away from the fan shroud.

[Sarge]

Seemed like back in the day (late '60's early '70's), most guys ran short manifolds and they ran them with a Berg linkage no problem.  I was a hack back then, more interested in getting on the street then in spending time setting things up properly.  Looking at my pic closely, I needed to take some extra time getting the fan shroud to fit better allowing the linkage to work better (note the left rod is screwed way in the right way out).  Back then, I never gave stuff like that much thought...

[So.Cal.Life]

      Back in those days the only tall manifolds I knew of were Empi's and people used their cross bar linkage as a package deal, the shorts were Deano and Bergs and both had fuel inlets away from the fan shroud , most everyone used Berg linkage, I don't remember anyone having any problems, myself included, I do remember complaints with Deano linkage because the rods were not equal length causing the carbs to open at different rates , between idle and full throttle, surging at cruising speed, etc.      KG

[nightmair nick]

while at it...mechanic fuel pump is working well enough for the IDA??or would you recommand electric pump with regulator?it is for a 1776 mild engine...

[Sarge]

while at it...mechanic fuel pump is working well enough for the IDA??or would you recommand electric pump with regulator?it is for a 1776 mild engine...

I have run stock fuel pumps all my life (a LONG time) with 48IDA's and had no problems.  Dare to be different.

[nicolas]

while at it...mechanic fuel pump is working well enough for the IDA??or would you recommand electric pump with regulator?it is for a 1776 mild engine...

I have run stock fuel pumps all my life (a LONG time) with 48IDA's and had no problems.  Dare to be different.

or stick with what works in the first place 

[Rick Meredith]

while at it...mechanic fuel pump is working well enough for the IDA??or would you recommand electric pump with regulator?it is for a 1776 mild engine...

I'll 2nd what Sarge said. Ran my 1776 with a mechanical pump and it was a few steps above "mild"

[JS]

while at it...mechanic fuel pump is working well enough for the IDA??or would you recommand electric pump with regulator?it is for a 1776 mild engine...

I'll 2nd what Sarge said. Ran my 1776 with a mechanical pump and it was a few steps above "mild"

I concur.