350 intake/carb suggestions

[nixtux]

I need to redo my intake again. It's leaking and puffing a little. I've been pricing out some aluminum intakes but I'm not sure what intake to get. I'd also like to replace the carb. Back story, the carb was rebuilt but they left some dowel pins in (or at least that's what they looked like.) I removed the carb and had those pins removed and put the carb on and they adjusted it. Problem is, it's missing like crazy and the back barrels don't open. I'm not sure if the missing is the intake leaking or not. I dont' think it is.

My plan so far is to get a >74 distributor, replace the intake with an aluminum intake (the current one weights at least 50lbs.) Replace the carb and probably get some stock exhaust manifolds. Although the price of headers is chump change for a 350.

I know the truck was pushing at least 300HP. It's a snappy old lady but it's missing so bad I don't want to drive it. I figure go ape on it and hopefully get it running good. I'm hoping to get some links for a intake/carb match that'll drop in. I'm not sure if rebuilding the quadrajet will fix it or not. Frankly I've dropped too much into it as is, so I figure replace it with something new and be done with it. That's assuming a intake/carb combo is cheaper than rebuilding it. Then again the last time it was rebuilt it was done wrong... Damned if you do, damned it you don't. I'm just tired of having shops do work and it's done wrong. Do it myself and if it's wrong, it's my fault.

Thanks

[nixtux]

I was thinking of getting a Edelbrock 2701. Either rebuild the quadrajet or get a reman.

Intake link http://www.northernautoparts.com/Pro...ctModelId=5239

I'm at a loss on the distributor. Checked out ebay. The truck has a point style currently. It was suggested that I upgrade to improve the timing or some
crap like that. Would this one be a decent enough?

http://cgi.ebay.com/ebaymotors/SBC-B...item4ceecbc3f0

[86FieroSEv6]

I feel your pain. I can't count how many carb's I've straightened out. Guess what? 90% of them were no more than putting shit back the way the manufacturer designed it. Just simple, good old mechanical restoration. As far as the "secondarys" not opening. Be aware that there is a cold operation lock out that prevents secondary throttle action until the choke comes off the fast idle cam completely. If your choke is screwing up that will make it run bad. Also, that big fat vacuum port looking dealy bobber at the front top of the carburetor? That is the bowl vent fitting, it is supposed to be hooked up to the evap system (charcoal canister system). At the very least, put a small filter of some kind on it, but do not plug it. That will upset the fuel mixture, especially during high temps. Wiggle the throttle shaft up and down, excessive movement here means the throttle shaft or it's bore in the throttle plate are worn and will need to be replaced or bushed to take up the slack.......worn throttle shaft/bores will affect idle mixture adjustment. Also, if somebody has overtorqued the carb. base that will induce vacuum leaks. Also, if somebody has used the wrong mounting gasket . . . . . . you can guess the rest.


Yes, I know all this because I am that old . . . . . . . . .

[geoffinbc]

Keep the Quadrajet. It is a great street carb. Your secondary throttle plates should open at full throttle but the air valve (plates on top of the throttle plates) will not open unless the air demand of the engine requires them to. A mild to medium performance 350 may never fully open the secondary air valve because it may only need 600CFM. However you can make adjustments to have them open sooner. Reman units should do the job if you don't want to take on the task of a rebuild yourself.

An Edelbrock intake is a good choice but there are cheaper ones that are just as good. Weiand stealth ram comes to mind. But sometimes if you know the right people the prices all level out.

Take that points distributor and burn it. They have no place in this day and age. MSD Street Fire HEI distributors are a great bargain so are the Pertronix stuff or DUI. There are other off brands that are less than a hundred but I don't think I would trust them.

I just grabbed a Pertronix Igniter II ready to run distributor, coil and MSD black plug wires for $320 for my father in laws 396. He was running points too and when I checked the spark with my plug tester I had a good laugh. Looked as weak and my VW Dune buggy spark. LOL

[nixtux]

I'm going to replace the distributor today. I think lack of spark is half the issue.

I'll probably get the intake and a reman. Then I'll try to rebuild the old one. Not sure yet.

The secondary opened until the intake was replaced. I'm guessing it has to do with the choke. I'm not concerned with getting that working as much as getting it so it's not missing. It seems to burn up a lot more fuel now than it did before. If I can get it running smooth, get the exhaust leaks patched up, a better/lighter intake, a reman quadrajet, hopefully that'll liven up the old girl. Get her running good. I figure in 5 years there hasn't been any major repairs ect ect. It's time to sink a little into her.

It's hard to tell if it's blowing coolant or not. If I put my hand to the exhaust pipe, I don't get any water. Then the weather is muggy and cool, so it may not be leaking. Better safe than sorry. An intake is pretty cheap and it's reasonably easy to change. I figure the drop in weight alone is well worth the investment. Lighter, should stay cooler, there doesn't seem to be a downside so.

[nixtux]

I called Advance auto and they have a Streetfire HEI for about 150. I think that'll be the first component. The guy that adjusted the carb earlier this week made it sound like killing the points distributor should fix the missing. Try to get that done in the next few hours. I have to go to a friends since my tools are in his garage.

Thanks for all the advice. It's really good info.

[nixtux]

It's pretty much official. The intake leaks... Took it for a quick cruise, no other vehicle had visible exhaust. When I got home, it was sputtering fluids from the exhaust.

I think I read the 2701 is a little better than the 2101, but I can get a 2101 locally so I think that will be the ticket.

http://shop.advanceautoparts.com/web..._1384847109___

Stock exhaust manifolds should be good enough I'd think. Either way it's better than the crap headers it has now.

The camshaft is a Comp Cam Xtreme Energy 242.

http://www.jegs.com/i/Comp+Cams/249/12-242-2/10002/-1


I'm thinking of getting Dorman Exhaust Manifold for now. A cheap fix it up. I'm not sure if that'll be the case since it already has shitty headers... Figured I'd get some advice first. No sense dropping several hundred into this if it's going to suck.

Thanks again.

[robertisaar]

my dad has a performer intake on his 70 monte 350... good intake, i think he's getting ~18MPG with it with a turbo 350 and like 3.3x gears and it makes decent power for being a weekend cruiser/back-up vehicle, even with the stock exhaust manifolds.

[nixtux]

my dad has a performer intake on his 70 monte 350... good intake, i think he's getting ~18MPG with it with a turbo 350 and like 3.3x gears and it makes decent power for being a weekend cruiser/back-up vehicle, even with the stock exhaust manifolds.

I'd be suprised if I'm getting 5MPG right now. Before the intake went last fall, it got around 10-12MPG on the highway and around 2-4MPG in town. I was pretty hard on it in town. But you cannot stand by while some douche hot rods his Honda. I put about 9 gallons in and put 45miles on it before I had to put more fuel in. 20 miles was over a quarter tank. It's just awful right now.

It's suprising how poor a engine performs when things aren't on the up and up. I can't afford to drop the Ben's into this right now but I have to because I can't afford the gas let alone the bill to tow it home, if it breaks down.

[86FieroSEv6]

You don't need an intake mani'. Get the carburetion straightened out. As for the distributor, I ran a single point from a '71 Impala (full size cars had the best factory advance curve) and a Holley 750 double pumper on a 350 with a Crane cam (.454 gross lift) against a stock TH350 with a twenty dollar Mr. Gasket shift kit in it. The rear was 3.08 open type diff' and all of this was in a '72 Ventura sporting L50-15 tires. It was able to hit 14.90@90mph on demand, very consistent car. Fuel economy was around 16 in town and 18-20 hiway. I was using a Holley Dominator II intake, but when I switched back to a stock truck heavy duty four barrel intake I barely lost a tenth and the cam didn't seem to mind plus it helped the street manners a bit. I'm betting it was the improved port velocity of the longer runner stock intake that caused it.

[nixtux]

The main reason I planned to change the intake was because it's lighter. A little bit easier to get it on and off if I have to do this project alone. I'm not 100% on how much the current intake weights but it has to be at least 50lbs. I'm thinking a little bit more since my two cats weight about 25lbs and that's not much weight. I think it'd be a task to set it on my own. The last time I had a friend and even that was somewhat of a challenge.

However, given the cash situation, it is good to know that it probably won't make any difference. This time just make sure to seal it up better. The RTV I had was a bit old and it didn't want to come out very well. Overall, it was a 1/8in bead, albeit spotty. At the time I wasn't sure if it was the intake so I figured just get it done and find out. Apparently it was the intake and apparently it will need to be redone. This is a hobby so, for the most part, I don't mind redoing things. It's learning lesson.

You don't need an intake mani'. Get the carburetion straightened out. As for the distributor, I ran a single point from a '71 Impala (full size cars had the best factory advance curve) and a Holley 750 double pumper on a 350 with a Crane cam (.454 gross lift) against a stock TH350 with a twenty dollar Mr. Gasket shift kit in it. The rear was 3.08 open type diff' and all of this was in a '72 Ventura sporting L50-15 tires. It was able to hit 14.90@90mph on demand, very consistent car. Fuel economy was around 16 in town and 18-20 hiway. I was using a Holley Dominator II intake, but when I switched back to a stock truck heavy duty four barrel intake I barely lost a tenth and the cam didn't seem to mind plus it helped the street manners a bit. I'm betting it was the improved port velocity of the longer runner stock intake that caused it.

[nixtux]

Last night I ran and did some quick errands. At a light, it started sputtering real bad. It almost looked tinted blue between the smoke and the sputter. I was maybe 2 miles from my house so it was a quick return trip. Half way there the exhaust leak clacking went away and was muffled. When I got out of the truck it smelt like gas, heavily. The oil also smell like gas. It's also really dirty considering I changed the oil 120 miles ago.

Just looking for suggestions before I tear into it.

[86FieroSEv6]

Hmmmmmmmmm, are you still using the stock mechanical fuel pump? If so, I would pull it and make sure it's not leaking into the crankcase. Other than that, your carburetor may be flooding, either due to a faulty needle and seat, float or choke not opening.

[nixtux]

Hmmmmmmmmm, are you still using the stock mechanical fuel pump? If so, I would pull it and make sure it's not leaking into the crankcase. Other than that, your carburetor may be flooding, either due to a faulty needle and seat, float or choke not opening.

I'm not sure on the fuel pump. I know it was new in 2002. It's attached to the block, maybe the oil pan. But I'm thinking it's the block.

I was thinking that maybe if it's missing bad enough, could fuel build up in the pistons and get pulled through the valves? Maybe that's stupid, but I don't know.

[86FieroSEv6]

It's probably misfiring because you have badly wet fouled a plug or two. Even the world's best ignition system and plugs cannot overcome wet fouling due to a fuel control issue. Case in point. My buddy's (everybody's got a buddy!) pro street Camaro has a nicely built small block with a beast of a Holley on it. BTE prepared and tuned locally at XXX in Pensacola. Back a while back, we chewed through a couple of power valves. He's got an MSD6AL with a Blaster coil and we still fouled up the plugs. Mind you, his ignition system definitely packs a wallop, I speak from some oh so painful experience. Still, it was no match for improperly atomized raw fuel. You gotta get your carb' squared away first or everything else is wasted money.

http://www.youtube.com/watch#!v=yALmUynDm2k