Vortec 4.3 v6 chevy intake mod,wood gas plentom under the carb.with spider injection intake manifold/untested

Has any one built a wood gas plentom in place of the half plastic intake manifold with the spider injection eliminated.I think some one on the dow did but i havent heard the results,and he was moveing too throtle body,not carb.

We built a system using a 4.3, we eliminated the EFI and used a marine conversion intake to carburetor. If it were me Id yank that 4.3 out and put in 96 to 99 vortec V8 in its place. We do the same thing with them and install aftermarket carb intakes :fire:

You may be referring to me. Yes I tried, but ended giving up with building my own. Went with what Matt had said and bought a cheap ebay carb intake, ground out and smoothed the intake runners and will put a TBI adapter on top. Building the custom one I new I was going to run into vaccum leaks so spent the $150 to avoid the headache. The intake runners once ported look just as big as those of the stock intake manifold.

my 2 cents

YAA thats who i was looking for,i kinda thought you hadent tryed it yet,thanks for responding dustin m and matt,iknew they had them carb intakes ,after researching on google, i am fitt too try it with carb and 4- 2" tubing nippels, too the plumming, so i will post the results when tested,as money is that tight at the moment,it may get a wood gas test before i abanden the build,as i dont think the runners are needed with wood gas that is all ready in the vapor state, I dont use for hauling any long distance so the 6 banger will have too do,as this truck model came from factory with a 6 cyl, its got plenty of gear with the 350 rear end, 700 r4 tranny too be,Thanks PS


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Thanks matt that must be the year of this motor,as the guy that sold it too me on creadit ,no hurry,no knocks, said it was 1989,he must have meant 1999,with the spider injection,hope the heads dont leak,suposed to have been a crate motor allso.//ALLSO i have a 1980s range distributor that is just missing the spider intake,after i weld 3/4 " block too make room for computor less distributor,THANKS FOR RESPONCE’s

Hi matt,how do those motors work with the edelbrock,or after market intake,with the carbs, i mean do they work ok without changeing the cams.THANKS

It won’t skip a beat! You may want to play with jetting the primaries, but that is about it. This is where having an 02 sensor setup will come in handy. The Edelbrocks are very easy to tune, they are what I use and are some what inexpensive. Might find a good used one on Craigslist or Ebay.

I will keep an eye out for those on craigs list ,and ebay,thanks much on the details.

Hey guys. I’m a 4.3 V6 man. I have my '94 woodgas truck and I have a 2003 everyday 4.3 V6 truck. What are you guys talking about? "spiders feeding into a black box and something about a “muffler bearing”. Some pictures along with this conversation would be greatly appreciated.TomC


HI Tom C i was jokeing on most of that odd stuff, sorry about the mix up,allthough they did make spider injectors a few years on the vortec v 6 ,whare half the intake is plastic,and the intake bolts go strait down ,not on an angle like my 1991 astro motor, i could change the heads if i have too lator, this motor i got must be 1996 too 1999. So i am stuck makeing a plenton for my carb truck, when i get the plentom built i will post the picks,Thanks

hey kevin ive been running a 5.7 with that spider injection so far no problems but listening to the intake burning out stories makes me cringe .I just acquired another engine with a case of the nocks but the top end is good im gona try making an intake that will relocate the spider out up top like a throttle body injection that way I hopefully can run 1-8 injectors for highbred mode .and not half to worry about a fire down in .

Hi paul M good luck with your experiment,I gess them carbs are the worst for fires ,I am building a metal plentom in place of the plastic one only taller,with carb on top and wood gas below, if i had a way too control some injectors i would use them instead, as like you say they are good at hibriding.I wonder how them marine intakes work for less cleaning.Thanks

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spider vortec v6 plentom/ how would i keep the carb from fast idleing with the floppy throtle plates from air and and gas control from wood gas plentom.or would it still work with throtle body type type throtle plates.It looks like one would need ball valves to control the air in, and have the other two ball valves closed from gasifier systom,in order to maintain the proper vacuem too the carb,not much in the book other than i did see one thing i will change is the carb bolts come up from bottom,instead of welding nuts to plentom,Thanks Chris Saenz,on the extra design ideas.PS the notch in the intake plenton was added to make room for the 80s distributor.I think i could have used an old points distributor,without haveing to weld the aluninum block to the intake, that would be the easyest way to use vortec spider intake.

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Replaced the nuts with studs,less app too corode,or rust any threads, got the slag all off and then painted with rustoium barbique paint, cooked in ovon at 350 f for 45 min, or so, allso put studs on all the bottom plentom bolts too make easyer for RR.THANKS

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Good morning Kevin .

I may be having a little trouble following the thread …

It looks like you plan to use a compartment below the carb to bring the wood gas to the motor. I can see how the carb will function but I don’t understand how you will throttle the wood gas .

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Wayne is right, you’ll need a single point of entry for the mixed air and gas. Your picture seems to show four…?

HI WAYNE,Thanks for responce. Just wounderd how bad the standard home made wood gas throtle plates would seal while trying too run on petro, I think i would move two of the lower plentom throtle plates, and open the the other two air valves on the bottom plentom for wood gas.I probbly missed something on the carb setups, but i am thinking the throtle plates on the plentom for air control, would work with less leaks while on petro,if they were some sort of ball valve,VS the throtle plates.

I dont understand the real differance between the above and below the carb problems, That might make a good thread in itself . In my case i had too make a plentom anyway,due too the spider intakes are like a standard intake with the top half of the intake cut off. That could be good when above the hood space is limited,for the carb setups. waiting for intake gaskets too get here, raining this morning

HI there chris saenz, i can see now i missed the boat on carb setups, i can use the other pipes for pop offs and block them if needed,in other words it wont work like it does when above the carb or when controling through the air cleaner above the carb, what would be the gain by useing the single port and pipeing the air in with the wood gas pre plentom, I did see your truck vidios on your pluming, wasent sure why it was plumed that way.Thanks

It seems if i bring the gas in the side of the intake,i am right on top of a dual port,too the point it would probbly get more gas in one side of the motor,maybe i should bring gas in above carb too get more even gas flow,due too the spider intake setup,whare as its not the same as when the plentom brought the gas in from the top of a standard intake.THANKS

Wayne’s standard setup brings in gas and air from four points, mixes them in the air cleaner housing, and feeds them through the original throttle. For this setup the gas / air must be mixed before the throttle. It’s possible to throttle them separately but this is far more complex…

If you plumb it in under the throttle body the way you have it now, as soon as the woodgas comes in the motor will run away (overspeeding), because it has a wide open supply of fuel and air and no throttle…

My setup had a single point of entry, single throttle body, which adds a second throttle pedal. The air and gas are mixed before this point. I recommend this setup exactly for you.

If it were up to me, I would cut off all four pipes and weld them shut, and instead weld on a 3" pipe leading to a 3" throttle body, and build out your air mixing beyond that.

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