4 barrel carb questions

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38 Dodge

38 Dodge

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I would like to see if anyone can help out. which I'm sure has been covered before I just cannot seem to find what I'm looking for. I'm thinking about putting a 4 bbl carb on my slat I have an intake and a carter 400 cfm carb. what all is needed to accomplish this mod? I would like to try and get part numbers for cables, brakets, and miscellaneous.
Now for the kicker I'm tinking of doing this on my 62 Valiant wagon with the mechanical linkage throttle.
Thanks for any and all assistance.
 
Just parking a 400 cfm carburetor on a stock engine will produce nothing but drivability issues, and lower fuel mileage.

In order to get any benefit from that much increase in carburation one needs to install oversized valves, increase compression, re-curve distributor, increase size of exhaust system, and probably change to a more performance orientated cam shaft.

You have to think of an engine as an air pump, and how much air can it move. No matter how big one makes the opening to the engine, unless the rest of the pump is enlarged it still can only move the same amount of air before the enlarged carburetor was installed.

Check out what Josh has to say about carburetors on the other /6 site:
http://slantsix.org/articles/Josh_Carb_Article.htm
 
The throttle linkage problem is easily solved. Just get a gas pedal and throttle cable from a 67 and up A body. I think I have extras. If I can scrounge them up you can have them for shipping because the last set was given to me so the least I can do is pay it forward. Installation is real easy. A blind man could see how. As far as the carburetor itself, adding a 4 barrel to a stock slant will probably put the fire out. You need a good intake (Clifford or Offenhauser) and larger exhaust pipe. Also, milling the head for more compression is highly recommended. I like the Thermoquad. Its small primaries lend it wel to a variety of applications. Being a vacuum secondary carburetor, they only flow what the engine demands, so as long as the primaries are not too rich (and they never are) you'll be fine.
 
I can say by experience that my little 170/ excepted my 390 holley very welland my mpg went up and performance, but I did the following
I removed the very small under 1 3/4 inch exhaust pipe system all the way back and added a split manifold
I think that it could have be accomplished by just going to a single 2 1/4 pipe..
Billy (Leanna's man) did go threw my holley to make sure it has not been mest with and it is a tride and true 390 cfm now. I changes the 13'' wheels to 14'' before I removed the pea shooter and little exhaust, I was getting about 19 to 20 mpg and know getting an easy 23 to 24 mpg. I quess I got lucky and the 170 revs up clean and loves cruising 70 mph know, before it was all changed out the temp would climb, know it don't..
The cool fresh I am sure made a big difference I am sure= 4.0 Jeep breather.
I used a 72 duster throttle cable and pedal threw the same hole my solid linkage went threw and has been flawless for 2 years of daily driving... I may have just got lucky i guess. Or was it the correct plug installation ?
This is a bone stock low deck 170 /6.
I have a very lite 66 sedan = 2.700 and running the stock 3.23 gears.
 

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Oop's I have changed out the gas line to a steal line :coffee2: I just can't find the picture :D, this holley is a ford carb and has the very small primaries like StrokerScamp is talking about.
 
Update, I'm running headers and I have a head in the shop getting reworked what are some good part numbers for larger valves, springs I have no MOPAR people around here so machine shop does not know. also will I need to change out the push rods if I shave the head? What would be a good cam for a hot little street rod?

Memike,
what did you do about the Kick down linkage?

StrokerScamp,
I'll take you up on the offer for the throttle pedal and cable.
 
38 Dodge said:
Update, I'm running headers and I have a head in the shop getting reworked what are some good part numbers for larger valves, springs I have no MOPAR people around here so machine shop does not know. also will I need to change out the push rods if I shave the head? What would be a good cam for a hot little street rod?

Memike,
what did you do about the Kick down linkage?

StrokerScamp,
I'll take you up on the offer for the throttle pedal and cable.
Click to expand...

Cool. Let me make DAMN SURE I can put my hands on the duplicate pieces and I will let you know. I got Oregon to grind me a custom grind for mine. .489 and 230 @ .050 ground on a 105 LSA. They reground my stock cam for 70 bucks.
 
38 Dodge said:
Now for the kicker I'm tinking of doing this on my 62 Valiant wagon with the mechanical linkage throttle.
Thanks for any and all assistance.
Click to expand...

Offenhauser made a linkage adapter kit to connect the stock slant 6 rod linkage to a 4 barrel mounted on their slant 4 barrel intake. Not sure if it's available anymore. I'll take some pictures of the one I have, which is NOT for sale.
 
SS,
The cam you are running is it a good grind for a strip / street?
 
38 Dodge said:
SS,
The cam you are running is it a good grind for a strip / street?
Click to expand...

Yup. It's a pretty nasty little grind though and would fair better with some port work.
 
38 Dodge said:
Update, I'm running headers and I have a head in the shop getting reworked what are some good part numbers for larger valves, springs I have no MOPAR people around here so machine shop does not know. also will I need to change out the push rods if I shave the head? What would be a good cam for a hot little street rod?

Memike,
what did you do about the Kick down linkage? No kick down linkage, I have a 3 speed standard

StrokerScamp,
I'll take you up on the offer for the throttle pedal and cable.
Click to expand...
SS can make this happen :cheers:
 
I have a question for you all, I have found the following valve springs at my fathers garage and wanted to know if I could use them in my /6 valve up grade the part number on the box P4120249? I googled teh part number and they are for a SB.
Thanks
 
here are some pictures of the springs in question
 

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I run small block springs on my slant. That # says General Purpose High Performance
Cam lift range .430''/.500''
 
So they should work with this a cam 489 and 230 @ .050 ground on a 105 LSA. ALso to show my lack of this subject what does LSA mean?
 
38 Dodge said:
Update, I'm running headers

what headers?? 6-1? or 6-2 with split collectors?? the single collector would be better for a stockish motor but dont over do it on exhaust pipe size, 2 1/2 for single and 2.25 for duals...

and I have a head in the shop getting reworked what are some good part numbers for larger valves, springs

1.7/1.44 are kinda the norm... enginbuilder on ebay has good valves... you can run BB springs but its a good idea to get new retainers (comp Cams 744-12).. also have the tops of the guides milled down so the retainers dont hit them...

http://www.ebay.com/itm/225-slant-six-Stainless-racing-valves-1-70-1-44-EV-8-/390401225877?pt=Race_Car_Parts&hash=item5ae5b9f495&vxp=mtr

I have no MOPAR people around here so machine shop does not know. also will I need to change out the push rods if I shave the head?

you can use stock length pushrods up to around .150 off the deck surfaces....

What would be a good cam for a hot little street rod?

a good cam would need info like gears, operating rpms, street only? auto or stick... yadda yadda... but i would think something like SS's cam, 230 @ .050 duration, with as much lift as they can give you... something to remember is that slants only have 1.45 ratio rockers (if you lucky to get that high) so your lift numbers will be less than as posted...
Click to expand...
 
L= lobe S= separation A =angle Yes on the springs you have.
 
Thanks for the info, I iwill be tapping you all for more real soon.
Thanks again

805 Moparkid the link you attached did not open.
 
So far, I caint find but one gas pedal and cable, but I KNOW I have another pair somewhere. I will keep lookin.
 
38 Dodge said:
Thanks for the info, I iwill be tapping you all for more real soon.
Thanks again

805 Moparkid the link you attached did not open.
Click to expand...

its the same as you posted lol... 3/8 stem 1.7/1.44 valves by enginbuilder...
 
SS Thanks
805MK Thanks you for the info. I will be ordering them tonight.
 
SS-If you cant find one,let me know and ill pull one.I got 3 out back.
 
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