I have a few performance questions

[Sniper X]

First lets talk about carbs. I have grown up hearing how everyone seems to hate Holleys for the street, but they seem to perform best on Chevy Small blocks.

I have a spreadbore 4bbl on my 74 but am not sure what it is. It may be a Quadrajet or a Carter but I have not looked at it yet to tell. I do want to install a aluminum intake and a new carb and possibly a cam. What cams are you SB guys running with say a holley 650 or Carter 650 and intake?

Also, what are the easiest headers to install on 74 Chev? I don't want to do shorty's unless they are easiest to install and if I do do shorty's, do some now install with the stock exhaust system?

Thanks!

Kev

[Pyrotechnic]

I run a Holley on the street and it works great. Back in the days when they didn't have power valve protection I could understand why people didn't like them, but now with that problem solved it's an invalid argument.

[a55togo]

i have had both edelbrock and holley's and i prefer the holley. as far as your question what heads are you using, are you planning on using your stock torque converter? and what rear gears do you have?

[Sniper X]

Originally Posted by a55togo

i have had both edelbrock and holley's and i prefer the holley. as far as your question what heads are you using, are you planning on using your stock torque converter? and what rear gears do you have?

4 speed with 411:1s so no problem on a mild to street strip cam as far as I remember. Heads are 194s and block is a 4 bolt main steel crank 350.

[Damien]

The Qjet you have now will be more then enough for what you are planning to do. Just give is a good cleaning and a carb kit. I have used hookers with out issues, but that was with a th350. I don't know about any clutch linkage issues you may run into. With long tube headers you are going to need to have some exhaust work done to get them hooked up, shorties are made to go in place of stock manifolds. Shorties will be easier to put on, BUT you will not see as much improvement over stock as you will with long tubes, so it really isn't worth it in my opinion.

[Sniper X]

Originally Posted by Damien

The Qjet you have now will be more then enough for what you are planning to do. Just give is a good cleaning and a carb kit. I have used hookers with out issues, but that was with a th350. I don't know about any clutch linkage issues you may run into. With long tube headers you are going to need to have some exhaust work done to get them hooked up, shorties are made to go in place of stock manifolds. Shorties will be easier to put on, BUT you will not see as much improvement over stock as you will with long tubes, so it really isn't worth it in my opinion.

It seems to carb well now, but I need to do headers and get rid of some exhaust manifold leaks by going headers. I also want to do a intake since I can get about 5 different ones on Cl that are like new for 50 to 75 bucks. BTW I have always had good luck with Q jets even on cars that are making 400hp and more. of course these were 860s or what ever that weird larger CFM Q jet is, not the littler 650 cfm's. I remember Q jets are rated at weird CFM compared to Holleys since the Q is speadbore.

[Damien]

Qjets are all capable of 780 cfm. You still are not changing enough to warrant replacing the carb. You will have to adjust the carb when you put the headers and cam in. The stock intake ports are going to choke the engine.
By keeping the Qjet you also do not have to change the fuel line or mess with changing the linkage keeping the project a little simpler.
For a cam, I've used comp's 252H in my '74 Blazer. It makes good power and has a smooth idle. I have 3.08 gears though.

[Sniper X]

Originally Posted by Damien

Qjets are all capable of 780 cfm. You still are not changing enough to warrant replacing the carb. You will have to adjust the carb when you put the headers and cam in. The stock intake ports are going to choke the engine.
By keeping the Qjet you also do not have to change the fuel line or mess with changing the linkage keeping the project a little simpler.
For a cam, I've used comp's 252H in my '74 Blazer. It makes good power and has a smooth idle. I have 3.08 gears though.

I might just do headers right now, and in a few months when it gets warmer outside, where I have to work on this truck, do a cam and manifold and keep the Q jet for reasons you stated. I hate messing with the fuel pump and linkage if I don't have to. I changed everything except the cam on my blazer and it all made a noticeable differnce but needed a cam for really better power.

Here's a pic of the blaze.

[3r!c84]

Originally Posted by Damien

Qjets are all capable of 780 cfm. You still are not changing enough to warrant replacing the carb. You will have to adjust the carb when you put the headers and cam in. The stock intake ports are going to choke the engine.
By keeping the Qjet you also do not have to change the fuel line or mess with changing the linkage keeping the project a little simpler.
For a cam, I've used comp's 252H in my '74 Blazer. It makes good power and has a smooth idle. I have 3.08 gears though.

i just put headers on my 305 with a stock qjet what do i have to change on the carb or adjust ?

[Sniper X]

Originally Posted by 3r!c84

i just put headers on my 305 with a stock qjet what do i have to change on the carb or adjust ?

nothing if it runs well. If there is a flat spot somewhere tell us where and you can rejet, but generally, on a car if all you do is headers there isn't much in the way of jetting change you need to make. Unless of course the car was very lean to beguin with.

[3r!c84]

Originally Posted by Sniper X

nothing if it runs well. If there is a flat spot somewhere tell us where and you can rejet, but generally, on a car if all you do is headers there isn't much in the way of jetting change you need to make. Unless of course the car was very lean to beguin with.

thanks for the help.i can realy see it when its running if its puffing out black smoke(runing rich) or not

[d10s69c10]

++ to the above. but if you are more into acctually replacing what you have right now you may want to look into a edlebrock performer kit seeing as it has a carb intake and cam all set up for your sbc so there isnt really much guess work.

as for headers i ran a hooker super competitions on my 69 with the siginaw 3spd had to make one small dent for clearance

[Damien]

I changed the engine in my blazer due to excessive oil consumption and left the cam in the old engine. I put a Wieand intake on and it was deffinently down on power compared to the original engine with the cam. I put the hooker long tubes on a few months later and did notice a big difference in power and picked up 2-3 mpg. I really missed my cam though. I am debating on switching to TPI or just swaping in a 5.3.

[Sniper X]

Speaking of cams and their power difference, I had a 1974 Dodge Ramcharger 4x4 I did a 3/4ton swap on and put a 426 wedge motor in it. The wedge motor had a solid lifter cam in it stock, and had about 450hp. It got as bad of mileage as you can figure and I was told to put in a RV cam for extra mileage. That was a HUGE mistake! The RV cam was more like a stock cam than the almost 440 magnum solid cam that came out of thew 426wedge, and it felt like I lost 200hp when I did that! I sold it or would have definitely swapped the wedge super stock cam back in or at least gotton a identical lift and duration roller or hydrollic cam.

[Sniper X]

I have a rebuilt 454 in my 78 I am thinking of swapping in this Spring. All I need to do is put on new valve seals and probably do a cam in it as well. I am sure my power will be acceptable then in the 74 pickup! I will then put this 350 in the 78 for the GF to use for ranch stuff.

[spinem]

theres a few things you neew to take into consideration.... a edelbrock or holly for race is awesome, combine that with a sloppy cam and bam! race car...
however
for the street this is not what you want.
stock quad-ra-bog's have small primaries and MASSIVE secondaries, this means when you want good MPG's you just fether the throttle, when u wanna go fast and watch ur fuel guage drop, smash it to the floor.

cams.

i had a 273 comp cam in my 72 chevelle, 9;5;1 flat tops with a bored out edelbrock with choke removed, it got awful mpg, about 7 but it would flop everybody who dared to race.... (besides this damn honda with a 100 shot of nos.) still mad about that one...
this car made buku HP, it got me a few tickets....and it was a four door! hahaha.. I broke my lifter studs twice withthis stupid wicked cam...

any ways!..
if you want driveability and <b>reliability</b> rebuild the stock carb, throw in a RV cam, get a gear drive and u should be happy.

Headers, simple cheap HP, sumit or jeggs, 89.99+S&H will get you some full leanth headers.
Only go shorties if you plan to put it on its nuts... (lower)
If you want more info send me a "PM", for I will not be checking this thread again, good luck!

[Damien]

I'm not crazy about the "RV" cams because they are a one size fits all type of thing. The price is generally reasonable on them, but for the amount of work and money you will spend for lifters and gaskets, I would rather have something that is matched to the vehicle better ie weight, gearing, tire size, intended use.