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Out of curiosity, after everything is running smoothly and the tune up is complete, what performance mod would be my best bang for the buck? It's a 400 engine with edelbrock heads, and a Holley double pumper carb. Everything else is stock.
Exhaust. RA cast iron re-pop exhaust manifolds, 2 1/2" duals.
 

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What do you mean by this?
LOL, you need to get out more often. Any Pontiac enthusiast knows what 4:33's are. They are the factory mandatory rear axle gear ratio on the 1967-'68 Ram Air powered GTO's, and optional after that. All out racing gear and not great on the highway. Will wake up any engine due to the acceleration factor they provide. So cheap means to go fast, but gas mileage is non-existent, uncomfortable RPM's on the highway, adds additional wear to the engine due to use of hgher RPM's at lower road speeds, may whine, probably will have traction woes, but...........your car will scream when you can hook-up.
 

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Out of curiosity, after everything is running smoothly and the tune up is complete, what performance mod would be my best bang for the buck? It's a 400 engine with edelbrock heads, and a Holley double pumper carb. Everything else is stock.
If you changed the heads/intake/carb, but didn't get a cam to go with it, you will probably gain one heck of a lot from that.
As mentioned, freer flowing exhaust will help a lot. The RA manifolds are a great choice. Of course headers are going to give you the best flow, and they're so darned easy to install on a Pontiac (sarcasm font). Before you change the cam, you'll need to decide what you're going to do for exhaust because that should be taken into account when you select your cam.
4.33 gears will feel like +100 HP, but you only want to go there if you're wanting to be in "on" mode all the time. Particularly if this is an automatic. You will be screaming RPMs just to go 60mph.
 

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Discussion Starter #26
The car has the 4-speed manual close ratio. I mostly drive this car on the streets, so RPMs won't bother me. Where would be a good place to find 4:33 gears? Ames performance doesn't seem to have anything. I'm very interested in a cam as well. What cam would you recommend with the performance mods it currently has? I would have a shop install the cam.
 

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Discussion Starter #28
So after completing the tune up, they are able to get spark just fine and dandy but they are having a fuel issue now. They believe its my Holly carb.

They can either rebuild it for $350 dollars, or we can put on a new one. They are recommending a Holly 4777 650 CFM. My question is, if I'm going to spend $500-600 on a new carburetor, is this my best option for performance? Or is there something better you would recommend?
 

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I would check out Quick Fuel Technology carbs....Holley owns quick fuel, it is almost identical only much more tunable.

their 650 street brawler carb is like $370 ,...you can buy direct from factory or JEGS, summit whatever....when you have a QFT you can curve the fuel mix, but mainly if you are having any idle problems the air bleeds can be changed with a screwdriver.

you have to have a shop that knows how to do it, but easily done. Check them out.
 

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What did they determine about the no spark issue and if you don’t mind what did that cost you?
 

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If the engine is stock, get rid of the double pumper and put the quadrajet back on for a smoother, better running car. The Q-Jet was good enough for the Ram Air IV so it will do the job even if you put a big cam in your engine. A Q-Jet rebuilt by someone who knows what they're doing will run you about $4-500, but is well worth it.

Unless you're driving on the track all the time 4:33s are a little extreme. With a 4 speed close ratio you more than likely have 3:90s now. (That is if the close ratio transmission came with the car originally) and thats close enough to having 4:33s.
3:55s would be a great all around gear set for highway and street driving and will work behind the close ratio trans.
 

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Am I the only one that puckered up when he said the shop wanted $350 to rebuild the Holley? Maybe I'm out of touch but that seems terribly high.

650 CFM is a nice mother-in-law carburetor, but going the wrong way for performance. Maybe something in the range of a Holley double pumper -- oh wait!

Car probably came with 3.90's from the factory, but I've seen quite a few 3.55 special order rears. Pretty high ratio for performance work with a close ratio trans. Figure the 3.55's and close ratio is about the same first gear ratio as a wide ratio trans with 3.08's.
 

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Am I the only one that puckered up when he said the shop wanted $350 to rebuild the Holley? Maybe I'm out of touch but that seems terribly high.

650 CFM is a nice mother-in-law carburetor, but going the wrong way for performance. Maybe something in the range of a Holley double pumper -- oh wait!

Car probably came with 3.90's from the factory, but I've seen quite a few 3.55 special order rears. Pretty high ratio for performance work with a close ratio trans. Figure the 3.55's and close ratio is about the same first gear ratio as a wide ratio trans with 3.08's.
That’s why I was wondering about the tune up,get b out of there before he has to get a 2nd mortgage to get this thing running
 

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Discussion Starter #34
I'm definitely not very experienced with carburetor-ed engines, but here's what I believe the shop said they did:
-New Taylor plug wires
-New cap and rotor
-New points and condenser (But they went with some sort of electronic system which will allow me to never have to worry about replacing the cap and rotor???)
and a few other things that I can't remember. They were estimating around $500 for these items which included labor.

With a new carburetor (close to $600), and install, they were guestimating around $1300 for everything out the door.

I don't have the original carb that came with the car, I was just told it was a holly double pumper, but they were saying that it wasn't actually a double pumper due to it having vacuum secondaries or whatever. Clearly I don't know much about these lol.

If a 650 CFM is a "mother in law" carb, what would be the best performance carb for a mostly stock 400, with only edelbrock heads. (I might want to to do exhaust in the future). My mechanic raved about Q-Jet carbs, but said they don't make them new anymore, and I obviously don't have the original.
 

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Millions of Q-Jets were made. And there are basically only two sizes. 750 and 850 CFM and two versions, Chevrolet /Cadillac (side fuel inlet) and Pontiac/Buick/Oldsmobile (front fuel inlet). They were used on 230 cubic inch six cylinders through 500 cubic inch Cadillacs so are very versatile. Over the years Q-jets were continually improved and adapted to operate with on board computers. With all that being said they are still out in the market place as used units. But...
Do not buy from a parts store, or Rock Auto or catalog stores. They will sell you a generic Q-Jet that went through the rebuilders assembly line. There are individual rebuilders out across the country that will custom build to your engine specifications. Here are a few.

ourservices.html

Cliff Ruggles is considered one of the best Q-Jet people in the business. He no longer builds them but has a website, parts store and forum just for the Q-Jet. He will gladly give you advice as to what you need as will the other builders.

 

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I’m sorry bwayney I know you probably don’t have the knowledge on these cars and I certainly don’t want this shop to take advantage of you.Do you any club or car cruise in buddies to help you out on the goat? I Agee totally with 052 and lemans guy on the carb issue I would try to locate a Q jet if you could. But get a “car guy “ to look and help you out. We here at the forum are happy to give you suggestions but I think this shop is not getting you know where but filling there cash register
 

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Yep, need to find a club! Check GTOAA for a local chapter, or start talking to guys at car shows with similar vintage cars. You'll quickly find out who the local ripoff artists are, and (hopefully) who the local heroes are. And there's usually at least one "motorhead" in the club who will show up on a Saturday and hold your hand while you fix it yourself.

Sadly, a lot of "mechanics" and "garages" are as lost as you are when it comes to working on cars with points and carburetors. Even more lost when it comes to modified cars.

How was the car running before you started working on it? If you still had points ignition and it was a little rough, it was probably time for a full tuneup. If the points were marginal, and the plugs were gapped at .045, probably just didn't have enough grunt to fire the plugs. I like Pertronix ignition conversions. Pontiac Jim will argue.

Points ignitions require a ballast resistor or resistance wire to the coil to drop the voltage from 12v down to about 8v. There are three different Pertronix ignition conversions (plus full distributors). The original Pertronix is just an electronic switch that replaces your points and will run okay on the (stock) resistance wire. Pertronix II and III are happier with a full 12 volts, which requires some wiring changes. And of course we don't know for sure what brand conversion they used.

If you didn't have a fuel problem before, you shouldn't have one now. A light tweak of idle speed and mixture is usually part of a tuneup. Ignition timing also affects idle, and should be set before final carb adjustments.

Another big advantage of finding the "motorhead" in a club is that you can get advice from someone who's not trying to sell you something. Any bonehead can bolt on a carburetor. Even a newly rebuilt carb will require tweaking in for best performance. And it takes a minor genius to reject a carb to match a modified engine and actually have it run better. And there are Holley guys and Quadrajet guys who may be proficient with one or the other, or both. If the mechanic you've found is preaching Quadrajet, he may know what he is doing.

Your car came with a Quadrajet. If its relatively stock, it would probably be relatively happy with a parts-house rebuilt carburetor. Pontiac spent a lot of time getting it right.

Or you could spend an extra $500 (or more) and get a correct restored carb from one of the specialty houses. Better? Probably. Worth it? Maybe.
 

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Yep, need to find a club! Check GTOAA for a local chapter, or start talking to guys at car shows with similar vintage cars. You'll quickly find out who the local ripoff artists are, and (hopefully) who the local heroes are. And there's usually at least one "motorhead" in the club who will show up on a Saturday and hold your hand while you fix it yourself.

Sadly, a lot of "mechanics" and "garages" are as lost as you are when it comes to working on cars with points and carburetors. Even more lost when it comes to modified cars.

How was the car running before you started working on it? If you still had points ignition and it was a little rough, it was probably time for a full tuneup. If the points were marginal, and the plugs were gapped at .045, probably just didn't have enough grunt to fire the plugs. I like Pertronix ignition conversions. Pontiac Jim will argue.

Points ignitions require a ballast resistor or resistance wire to the coil to drop the voltage from 12v down to about 8v. There are three different Pertronix ignition conversions (plus full distributors). The original Pertronix is just an electronic switch that replaces your points and will run okay on the (stock) resistance wire. Pertronix II and III are happier with a full 12 volts, which requires some wiring changes. And of course we don't know for sure what brand conversion they used.

If you didn't have a fuel problem before, you shouldn't have one now. A light tweak of idle speed and mixture is usually part of a tuneup. Ignition timing also affects idle, and should be set before final carb adjustments.

Another big advantage of finding the "motorhead" in a club is that you can get advice from someone who's not trying to sell you something. Any bonehead can bolt on a carburetor. Even a newly rebuilt carb will require tweaking in for best performance. And it takes a minor genius to reject a carb to match a modified engine and actually have it run better. And there are Holley guys and Quadrajet guys who may be proficient with one or the other, or both. If the mechanic you've found is preaching Quadrajet, he may know what he is doing.

Your car came with a Quadrajet. If its relatively stock, it would probably be relatively happy with a parts-house rebuilt carburetor. Pontiac spent a lot of time getting it right.

Or you could spend an extra $500 (or more) and get a correct restored carb from one of the specialty houses. Better? Probably. Worth it? Maybe.
Apparently, REJET is not a word! This damn computer has "corrected" it twice!
 

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Toss in a hyphen and call it re-jet and the computer should be happy. If plug wires were disturbed at the cap all it takes is to be one terminal off and many times the engine won't even burp - just cranks over. Remember also that Pontiac distributor rotates counter-clockwise so firing order will be backwards around the clock with 1-8-4-3-6-5-7-2
 

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Discussion Starter #40
Just an update for everyone:
After getting the Holley 0-4777C 650 carburetor on, the car ran great. They put it on the dyno, and they were able to get 229 WHP, and 315 lb-ft of torque. This is after they messed with the timing a little bit, and these are the best numbers they were able to get.

However, like a bad dream, on the last dyno pull, the water pump blew, and one of the rear brake lines that was rusted broke. So it looks like I'm going to be putting more money into this.

One question I have is, would it be cheaper to buy all new brake lines and put them in, or just replacing the one rear broken one? My worry is that if that one was rusted, the others are as well.
 
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