Dual carbs on a 40 horse

[danny gabbard]

I am going to put two 28 PCI-1 carbs off 36 hp on a motor I am doing. Did any body in the early days make any singleport manifolds for a 40 horse ? If not I will have to make some! Any Ideas on tube lengths and angles on makeing manifolds, I want to make the hp towards the bottom end for driveing. And it will have a manual choke with stock choke cable on dash to go to both carbs for those very cold winters driving. Also looking for one more NOS carb. Thanks for any info.

[Zach Gomulka]

Pretty sure Danny Zepeda (sp?) has made something up and is offering "kits"... I think.

[kingsburgphil]

Here's a thought. Use a 36hp Okrasa kit from W/W less the heads. Weld/machine/adapter a pair of 40hp heads to accept the manifolds.
Or try to find a pair of 40hp Okrasa heads.

[Speed-Randy]

Pretty sure Danny Zepeda (sp?) has made something up and is offering "kits"... I think.

Hey Danny, Isn't he your best friend?

[danny gabbard]

There is no political correct answer for that randy, Thanks phil but heads are done and for me it would be alot less work to make manifolds and to me it would be kinda cool to have a manual choke on 6 volt car. It gets in the 20-30s in the winter here.

[Speed-Randy]

When did you get PC?

[danny gabbard]

Point taken !!

[kingsburgphil]

There is no political correct answer for that randy, Thanks phil but heads are done and for me it would be alot less work to make manifolds and to me it would be kinda cool to have a manual choke on 6 volt car. It gets in the 20-30s in the winter here.

Ok, how about this. Use the top half of the Okrasa manifolds, fab the lower half. As to the choke (mixture enrichment) assemblies, lots of 50's cars used variants of 32 PBIC carbs with cable operated chokes (PBI, PBIJ etc). Shouldn't be to hard to locate some used bits.
 

[danny gabbard]

I like the idea phil, But I have one nos carb and looking for one more, And makeing something from scratch is sometimes ez'r than buying something and reworking it. Plus as you mock stuff up you can always change it. I'm thinking for the manifods useing a hunk of tubeing with slight bend and lazor cut flanges and tack weld and when perf , Tig weld. and for the chokes useing a cable and cam to open and shut the baffles or chokes in carbs. Plus it will give me something to do and stay out of trouble!!

[kingsburgphil]

Sounds good Danny.  We'd all love to follow along with your project (pictures please). 

[danny gabbard]

Phil did you see your old car back up for sale on the samba ??

[kingsburgphil]

Phil did you see your old car back up for sale on the samba ??

OMG!!  the old gal is certainly worse for wear. I haven't seen it since 94', could be worse of course.
$125K....OMG!!  (colorful metaphor deleted). Since I don't know any of the parties involved, I'll
reserve further comments. But I will say that I hope Maribeth and I helped the cars more than we
hurt them.
http://www.thesamba.com/vw/classifieds/detail.php?id=1109077

[TexasTom]

Danny,
I have some orig single port Kadron manifolds I could send up to help with the pattern, length, etc.
Obviously the flanges will be different/smaller and the diameter.
Let me know ... they're only a box away.
TxT

[Bryan Nunes]

if you put 1300 heads on you can put the single port kadron manifolds on.

[Jim M]

Danny, here is a little info............http://www.thesamba.com/vw/forum/viewtopic.php?t=326666&highlight=manifolds

[danny gabbard]

Thanks Jim, That post gave me a few ideas !

[Zach Gomulka]

How about triples with progressive linkage?

[TexasTom]

Twin plugs no less ... That's just NOT FAIR

 

[qubek]

Zach, what is THAT?!

It somehow reminds me what my boss often says: "You did a very good, totally unnecessary work".

[Fiatdude]

Phil --- Nice ex car -- I'd forgot just how pretty that thing was

Danny -- on the 40 horse the shorter the tube between the carb and head the better -- (short tube torque, long tube RPM/HP) anything less than 8" would be perfect (most IDA manifolds are 6" but that was limit to carb height) -- hold the carbs on the side of the engine and find a happy spot where the Carb can set pretty and the linkage won't be to much of a bitch to make and fab from there. Since your making the tubes you can even move the carbs forward or back to meet your requirements. If you want to go crazy you can even do a cross ram manifold LOL

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[John Rayburn]

It's opposite. Long tube is more torque and bottom end. Short is more top end, RPM.

[danny gabbard]

Thanks  fiatdude, thats the info I was looking for ! I am still thinking on how to fab the dual manual choke thing, Maybe a cam type of deal with cables that go to both carbs. For linkage I am hopeing I can get a crossbar type under generator and stand.

[deano]

Ah, just cut a 48IDA in half and used them on both sides....

[Fiatdude]

It's opposite. Long tube is more torque and bottom end. Short is more top end, RPM.

Nope -- a torquer manifold for V8's is short runners and tunnel ram has the long runners for the High end operating RPM's

Quoted from wiki - --- Venturi effect - At low rpm, the speed of the airflow is increased by directing the air through a path with limited capacity (cross-sectional area). The larger path opens when the load increases so that a greater amount of air can enter the chamber.

Here is the full article --

http://en.wikipedia.org/wiki/Intake_manifold#Intake_manifold

Here is another article showing the difference in the 2 types of manifolds

http://www.carcraft.com/techarticles/0304_intake_manifolds_contrast/index.html

and then here is a picture of the bestest intake mainfold available LOL

http://s586.photobucket.com/albums/ss306/Fiatdude/?action=view&current=turbo.jpg

[Fiatdude]

Thanks  fiatdude, thats the info I was looking for ! I am still thinking on how to fab the dual manual choke thing, Maybe a cam type of deal with cables that go to both carbs. For linkage I am hopeing I can get a crossbar type under generator and stand.

CHOKE -- Who needs a stinking choke LOL -- Somebody in Europe is making a dual/split cable for throttles -- there is your choke and linkage --- go over the generator for your linkage....  It will be WAY easier and it'll keep your hairline in place instead you having pulled it out LOL

[Zach Gomulka]

It's opposite. Long tube is more torque and bottom end. Short is more top end, RPM.

That's what I always learned. Look at the long ass runners on that cross ram 440 manifold. You can't tell me that was for high rpm!

[John Rayburn]

It's opposite. Long tube is more torque and bottom end. Short is more top end, RPM.

That's what I always learned. Look at the long ass runners on that cross ram 440 manifold. You can't tell me that was for high rpm!

                                                                    Correct. It's a physical / speed of sound issue. The longer the intake runner, the more it's tuned for maximum power down low. The shorter, the more it's tuned for top end.

[speedwell]

Somebody in Europe is making a dual/split cable for throttles --

yes alexandro martin  ,he made cable/choke for the empi/speedwell sprintkit ,

[markvo]

Yes longer smaller port = low rpm ,shorter larger port higher rpm

[kingsburgphil]

Thanks  fiatdude, thats the info I was looking for ! I am still thinking on how to fab the dual manual choke thing, Maybe a cam type of deal with cables that go to both carbs. For linkage I am hopeing I can get a crossbar type under generator and stand.

Have you considered using only one choke? That's how I ran my Okrasa motors. Or no choke at all, just a hand throttle ala 356.