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Cal-look/High Performance => Cal-look => Topic started by: danny gabbard on March 15, 2011, 01:32:09 am



Title: Dual carbs on a 40 horse
Post by: danny gabbard on March 15, 2011, 01:32:09 am
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.


Title: Re: Dual carbs on a 40 horse
Post by: Zach Gomulka on March 15, 2011, 02:03:28 am
Pretty sure Danny Zepeda (sp?) has made something up and is offering "kits"... I think.


Title: Re: Dual carbs on a 40 horse
Post by: kingsburgphil on March 15, 2011, 02:51:50 am
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.


Title: Re: Dual carbs on a 40 horse
Post by: Speed-Randy on March 15, 2011, 02:58:17 am
Pretty sure Danny Zepeda (sp?) has made something up and is offering "kits"... I think.
Hey Danny, Isn't he your best friend? ;D ;D ;D


Title: Re: Dual carbs on a 40 horse
Post by: danny gabbard on March 15, 2011, 03:04:33 am
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.


Title: Re: Dual carbs on a 40 horse
Post by: Speed-Randy on March 15, 2011, 03:07:54 am
When did you get PC?


Title: Re: Dual carbs on a 40 horse
Post by: danny gabbard on March 15, 2011, 03:09:58 am
Point taken !!


Title: Re: Dual carbs on a 40 horse
Post by: kingsburgphil on March 15, 2011, 03:48:33 am
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.
 


Title: Re: Dual carbs on a 40 horse
Post by: danny gabbard on March 15, 2011, 03:57:39 am
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!!


Title: Re: Dual carbs on a 40 horse
Post by: kingsburgphil on March 15, 2011, 04:22:33 am
Sounds good Danny.  We'd all love to follow along with your project (pictures please).  ;)


Title: Re: Dual carbs on a 40 horse
Post by: danny gabbard on March 15, 2011, 04:25:42 am
Phil did you see your old car back up for sale on the samba ??


Title: Re: Dual carbs on a 40 horse
Post by: kingsburgphil on March 15, 2011, 04:51:49 am
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


Title: Re: Dual carbs on a 40 horse
Post by: TexasTom on March 15, 2011, 12:38:46 pm
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


Title: Re: Dual carbs on a 40 horse
Post by: Bryan Nunes on March 17, 2011, 06:06:56 am
if you put 1300 heads on you can put the single port kadron manifolds on.


Title: Re: Dual carbs on a 40 horse
Post by: Jim M on March 17, 2011, 18:16:16 pm
Danny, here is a little info............http://www.thesamba.com/vw/forum/viewtopic.php?t=326666&highlight=manifolds (http://www.thesamba.com/vw/forum/viewtopic.php?t=326666&highlight=manifolds)


Title: Re: Dual carbs on a 40 horse
Post by: danny gabbard on March 17, 2011, 18:47:25 pm
Thanks Jim, That post gave me a few ideas !


Title: Re: Dual carbs on a 40 horse
Post by: Zach Gomulka on March 17, 2011, 20:11:42 pm
How about triples with progressive linkage? ;)

(http://images.thesamba.com/vw/gallery/pix/776917.jpg)


Title: Re: Dual carbs on a 40 horse
Post by: TexasTom on March 17, 2011, 20:25:16 pm
Twin plugs no less ... That's just NOT FAIR >:(

 ;D ;)


Title: Re: Dual carbs on a 40 horse
Post by: qubek on March 18, 2011, 15:21:52 pm
Zach, what is THAT?!

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



Title: Re: Dual carbs on a 40 horse
Post by: Fiatdude on March 18, 2011, 16:52:38 pm
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

[attachment=1]


Title: Re: Dual carbs on a 40 horse
Post by: John Rayburn on March 18, 2011, 17:02:33 pm
It's opposite. Long tube is more torque and bottom end. Short is more top end, RPM.


Title: Re: Dual carbs on a 40 horse
Post by: danny gabbard on March 18, 2011, 17:06:42 pm
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.


Title: Re: Dual carbs on a 40 horse
Post by: deano on March 18, 2011, 17:49:01 pm
Ah, just cut a 48IDA in half and used them on both sides....


Title: Re: Dual carbs on a 40 horse
Post by: Fiatdude on March 18, 2011, 18:03:59 pm
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


Title: Re: Dual carbs on a 40 horse
Post by: Fiatdude on March 18, 2011, 18:27:22 pm
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


Title: Re: Dual carbs on a 40 horse
Post by: Zach Gomulka on March 18, 2011, 18:33:00 pm
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!


Title: Re: Dual carbs on a 40 horse
Post by: John Rayburn on March 18, 2011, 18:42:05 pm
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.


Title: Re: Dual carbs on a 40 horse
Post by: speedwell on March 18, 2011, 19:12:17 pm
Somebody in Europe is making a dual/split cable for throttles --

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


Title: Re: Dual carbs on a 40 horse
Post by: markvo on April 21, 2011, 04:22:12 am
Yes longer smaller port = low rpm ,shorter larger port higher rpm


Title: Re: Dual carbs on a 40 horse
Post by: kingsburgphil on April 21, 2011, 05:38:46 am
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.


Title: Re: Dual carbs on a 40 horse
Post by: dyno don on April 21, 2011, 06:27:09 am
 guys, long standing debate regarding manifold length performance...short manifolds/bottom end and more torque.... tall manifolds/mid range and top end.  This has been debated for years but experience speaks for itself. Tests were done YEARS ago. Seasoned Head porters will agree there is another 10 to 15 hp waiting from the middle to the top of the manifold. My experience as well as many others.  This is the main reason why the Berg 40/42/44 dcnf set up worked so well with astonishing throttle response and is also the case with short 48ida manifolds and fuel injection set ups.  peace out....


Title: Re: Dual carbs on a 40 horse
Post by: red baron on April 21, 2011, 07:54:50 am
guys, long standing debate regarding manifold length performance...short manifolds/bottom end and more torque.... tall manifolds/mid range and top end. 

exactly the opposite is right. Here you go:

www.ms-motor-service.com/ximages/pg_pi_0037_en_web.pdf


Title: Re: Dual carbs on a 40 horse
Post by: TexasTom on April 21, 2011, 20:17:04 pm
This is fun to play around with:

http://www.wallaceracing.com/runnertorquecalc.php


Title: Re: Dual carbs on a 40 horse
Post by: johnl on April 21, 2011, 21:27:07 pm
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

[attachment=1]
Hey, I've owned a pair of these for 25 years !!!  Talk about poor fuel economy, you guys don't have a clue until you put your foot into one of these and suck all of the atmosphere out of Los Angeles..  8) 8)
  http://www.youtube.com/watch?v=YLJVItmLPqM