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Discussion Starter #1
I have a 302 that I have removed the 2bbl intake and put a 4bbl intake with a bbl carb 4160 Holley on. I have set the timing to 6 degrees BTDC I have also turned the screws on the carb out two full turns. My problem is no matter what I do I cannot get the idle to drop dwon from a 1000 RPM. The Fast Cam Idle is set on the lower end of the cam. The car is extremly sluggish when you get up and on it. I mine as well put it in nuetral and push the dang thing. I'm extremly frustrated can anyhow offer any guidance, could be my carb is bad, or my timing is jacked up.:spank:
 

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timing

You didnt mention what year 302 you have but I would recommend advancing your distributer to 10 degrees initial for starters. Check your secondaries to make sure they are closed at idle as well. What size carburetor is it? The 4160's do come in an array of cfm's. Another thing to check is that your vacuum is hooked to the proper orifice on the carb. Was the car sluggish before you installed the new intake? You could have a vacuum leak somewhere. Try going around and retorquing all the intake bolts and the carb bolts as well. Have you adjusted the throttle stop screw? Do the primary butterflies go all the way closed?

Another thing to check is to make sure your choke linkage isnt preventing your primaries from closing as well.
 

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Discussion Starter #3
It's a 69 302 with 600CFM Carb you may be right about the secondaries the rebuild book said to open them 1/35inch which I did maybe I did. Maybe I opened them to much, but I did you a drill bit to measure it. I'm going to check for vacum leaks tomorrow. There has been some confussion amongst those who have helped me as to where the vacum lines go. I have two lines that are on a three line tree in the theromstat housing, then in addition to those I have another three line tree with three lines on it coming from the intake manifold directly behing the carb. I'm going to try and remember how I have this setup and type it. One line comes from the top of the carb to the thermo tree then from the thermo tree to the vacum retard on dist. from the vacum advance(front of dist) to the bottom of the carb. The back tree goes one to the tranny and one to the vacum can, and I can't remeber where the other one goes. If you have a diagram that would be extremely helpful
 

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timing

One thing, no vacuum lines from the vacuum fitting in the intake, behind the carburetor goes to the distributer. It could well be that you also have the advance/ retard vacuum lines backward on your distributor. Unless you have smog inspection for your engine where you live, I would just disregard the vacuum retard line going to your distributor and cap it off, and bypass the water heated vacuum tree on the front of your intake as well, and run your vacuum directly to the distributor. The reason for both the retard vacuum and the water heated vacuum advance line was supposedly to make your engine warm up sooner and meet polution standards. About all it did was to harm performance and gas mileage. The thinking was that people let their cars sit around idling til they got up to 160 or so degrees before driving them.

Your distributer vacuum should be running to a vacuum port in the bottom of your carburetor, usually on the passenger side front of the base plate. This is a metered port. I would cap off the upper vacuum port, as its not really needed.
The vacuum port on the back of the intake is for the transmission shift module, and if your car had some other things requiring vacuum operation.
On your secondaries, try seating the butterflies then turn in the stop screw until they just start to move, then leave them there.
Make sure your primary linkage is not interferring with them in any way when you do this, and vise versa when setting the primary butterflies.
 

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Discussion Starter #5
Thanks greatly for the information on the vacum lines you don't know how many people thought they knew how run those. Your answer seems to be the best I heard so far. I think on the secondaries I may have allowed the primary to get in my way and that is why they are opened more becuase I originally set the screw so that it just touched the arm and slightly opened the 1/35 inch. So I guess I need the pull the carb off and try that. even though it is late I'm have tempted to go out and try it. I lose sleep over this at nite :) I'll let you know what I discover tomorrow. Hey quick question you ever run up at Harland Iowa around 1996 thru 1999 . We use to race prostock up there, That and eagle raceway and I80 in Nebraska. I'm orginally from Omaha.

I meant Harlan not Harland... late typing is starting to go astray
 

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302

Never been around Harland that I know of. Im down in the armpit of Iowa, Lee County.

Er ah make that Harlan. I used to race late model sportsman and IMCA modifieds down here. Raced at Burlington, Donnellson, Eldon, and Bloomfield. All my drag racing time (legitimate) was out in California in the early 70's with a 69 Mustang with a 302 in it.
 

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302

Its possible but if you dont want to spend mega bucks to do it with a 302, I recommend at least building a 390 stroker 351 W, and go from there.
I ran a fastback with a 228 degree, 475 lift Sig Erson hydrualic cam in mine, with a Weiand Hi Rise, 600 cfm Holley, B&M valve bodied C-4, with Doublas headers, and a 3:1 rearend, and G-60-15 tires. I only used Low and 2nd.
Turned 14 flat with it. Gave Boss 302's, and 302 Z28's fits with it.
My heads were unported and ran stock 9.5:1 compression.

12's wouldnt be that hard to reach but 10's is going to cost money. Cubic dollars = Squared Horsepower, how quick do you want to go? Probably the best thing to do to get the ET down with your present engine would be to go with a 3.88 to 4.10 gear, with a locker pumpkin. I presume you have an 8 inch rear end in that stang?
 

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Discussion Starter #9
I have a 69 Torino Coupe I'm not sure if the internal's of the engine have been changed I just bought the car a month ago but from the exterior there are headers a 4bbl intake from an 83 stang, the 4160 carb, and that seems to be about it oh a autolite fuel pump. I'm looking for twelve's on a low budget I have and Eldebrock F4B cobra intake coming and for looks I have the street scoop II coming. My next to major purchase will be a new set of cylinder heads and a Eldebrock Carb not sure what else to do yet to keep me in a descent price range.

Oh I'm not sure about the rear end I assume it's and eight, the tranny is a C-4
 

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302

Being it has a 302 in it, unless it was ordered with a 9 inch, it is most likely an 8". But, dont knock it, Ive seen 8 inchers behind big blocks on dirt and take a lot of abuse.
 
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