Setup thoughts?

[Kasey 1977 K10]

I've been having fits with my QJet so I'm boxing it up and shelving it for now. I'm going to be putting in a new intake and carb and and wondering what HP and TQ I can expect when I take it to the Dyno for tuning and stats after its put back together.. thoughts about this or my plan?

CURRENT
Truck: 1977 Scottsdale K10 SW
Motor: 350 Small Block bored .30 with Roller Rockers
Cam: 360 RV Cam
Headers: Standard but not stock Headers
Intake: Stock 4 barrel intake
Transmission: Turbo 350 w/ Shift Kit
Transfer Case: 203
Front End: Dana 44
Rear End: 12 Bolt
Exhaust: Flo Pro FP760 Mufflers; 2.5" aluminized tubing; 2.5" stainless tips

NEW
WEIAND STREET WARRIOR INTAKE - CHEVY SMALL BLOCK V8 - PART# 8120BK
HOLLEY 600 CFM STREET WARRIOR CARBURETOR - Part# 0-80457S

 

[1987 GMC Jimmy]

What heads are you running, and if they've been worked that you know of, what are the new specs? Also, are the headers just standard long tubes? I'm assuming it doesn't have an air injection pump, but does it have air conditioning? Are you running just a thermal clutch fan?

 

[Kasey 1977 K10]

What heads are you running, and if they've been worked that you know of, what are the new specs? Also, are the headers just standard long tubes? I'm assuming it doesn't have an air injection pump, but does it have air conditioning? Are you running just a thermal clutch fan?

Here is the problem... This was originally my dad's truck and he had the engine rebuilt about 20 years ago by a very reputable local Chevy engine rebuild guy. It only has about 10,000 miles since that work but it sat for a long time. I had to replace the tanks, and lines as they were rusted and had the QJet rebuilt but that didn't go so well. But back to your questions. I called the guy (now in his 80's) that rebuilt it to see if he could remember which heads he put in. He said most likely he ordered new standard heads but he couldn't remember. No A/C. Everything else is pretty much stock besides the fact that he bore it out, switched up the manual for the 360 turbo tranny with shift kit, eddelbrock valve covers, new rv cam, new but standard heads and roller rockers. To get better details I'd probably need to pull it apart which I'm leaning towards not doing until I need to.

 

[1987 GMC Jimmy]

I don't think you have to pull it apart to get an idea. Just take a valve cover off and grab the numbers. If they're a GM factory casting, you can assume that they weren't ported and polished since you talked to the guy who did the work, but there's no guarantee, and if they're aftermarket heads, you can be pretty sure that they haven't been touched, and you can just research the specs and report back. It's just hard to make an assement without knowing what the heads are. They could be some little smogger heads, fuelie heads, or nice aftermarket heads. I can tell you they're not swirl-ports (lucky you) or Vortecs. They're just really important to know about if any guess on potential power is going to be offered. I'd say peek under the valve cover and see what you find or wait to see what the dynamometer says.

 

[Kasey 1977 K10]

Thanks guys! I wired it to ignition slot in the fuse box and threw on an inline fuse. I haven't put in the oil pressure switch yet so I'll have to be careful and not keep the key on with the engine off. How long would it take to do damage to the carb if I do? Now I just need to adjust the high idle down. Its pretty high when the choke is engaged.

Posted a couple of pics on the restore blog.
http://chevy.piratesproductions.com/2017/04/intake-carb-replacement.html

 

[1987 GMC Jimmy]

The choke element is bi-metal so it shouldn't allow itself to get too hot and burn up or anything like that, and the heater always has power to it when the engine's running. I guess what I'm trying to say I wouldn't worry about it just for a minute. If you need to have the key on extensively before you get your switch installed, just unplug the choke wire for good measure.

 

[Kasey 1977 K10]

The choke element is bi-metal so it shouldn't allow itself to get too hot and burn up or anything like that, and the heater always has power to it when the engine's running. I guess what I'm trying to say I wouldn't worry about it just for a minute. If you need to have the key on extensively before you get your switch installed, just unplug the choke wire for good measure.

Thanks! I watched a video on Holley.com on how to adjust the electric choke. Looks like you loosen the screws on the choke, hold the throttle all the way open, open the choke all the way, close it all the way and then open it just a bit and tighten the screws and let go of the throttle. That sound about right? Doesn't seem like I need to adjust any idle screws as the idle without the choke seems good to go. Never had an electric choke before so it's throwing me a bit for a loop. Thanks again.

 

[1987 GMC Jimmy]

Thanks! I watched a video on Holley.com on how to adjust the electric choke. Looks like you loosen the screws on the choke, hold the throttle all the way open, open the choke all the way, close it all the way and then open it just a bit and tighten the screws and let go of the throttle. That sound about right? Doesn't seem like I need to adjust any idle screws as the idle without the choke seems good to go. Never had an electric choke before so it's throwing me a bit for a loop. Thanks again.

Hmm, have you watched your choke as it opens? When off, it should rest fully closed and open up vertical when the choke is warmed up. It should have come pretty well adjusted out of the box if it was new. It sounds to me like the fast idle speed is a bit too high so maybe try dialing down the fast idle screw some if the choke looks good. I have much more Quadrajet dealings, but I've only dealt extensively with one Holley carb in my life. TBI is where I really shine, or at least I think so. There are others on here, though, who practically majored in carburetors.

 

[Kasey 1977 K10]

Hmm, have you watched your choke as it opens? When off, it should rest fully closed and open up vertical when the choke is warmed up. It should have come pretty well adjusted out of the box if it was new. It sounds to me like the fast idle speed is a bit too high so maybe try dialing down the fast idle screw some if the choke looks good. I have much more Quadrajet dealings, but I've only dealt extensively with one Holley carb in my life. TBI is where I really shine, or at least I think so. There are others on here, though, who practically majored in carburetors.

Thanks, I'll dial down the fast idle screw a bit and see if that helps! I think I had a really poorly tuned and built Quadrajet because this Holley is running sweet compared to it. The throttle response is night and day and it seems like I have quite a bit more power now. Going to be getting it dyno tuned. Interested to see the printout though I have nothing to compare it to as I have no idea what the HP and Torque was before. Thanks for your feedback!

 

[1987 GMC Jimmy]

Thanks, I'll dial down the fast idle screw a bit and see if that helps! I think I had a really poorly tuned and built Quadrajet because this Holley is running sweet compared to it. The throttle response is night and day and it seems like I have quite a bit more power now. Going to be getting it dyno tuned. Interested to see the printout though I have nothing to compare it to as I have no idea what the HP and Torque was before. Thanks for your feedback!

You're welcome. And yeah, that's probably the case with your Q-Jet or there was some damage that was overlooked either on purpose or out of stupidity. I had mine rebuilt by Mountain Main Carburetor in Hackett, AR. All I've had to do adjust is the curb idle mixture, and I couldn't be happier with the economy or performance. It's a snappy, fine looking carb, too. Here's a top down view without the little breather gasket on it. It's an E4ME; that's why it has plugins on it.

 

[Kasey 1977 K10]

You're welcome. And yeah, that's probably the case with your Q-Jet or there was some damage that was overlooked either on purpose or out of stupidity. I had mine rebuilt by Mountain Main Carburetor in Hackett, AR. All I've had to do adjust is the curb idle mixture, and I couldn't be happier with the economy or performance. It's a snappy, fine looking carb, too. Here's a top down view without the little breather gasket on it. It's an E4ME; that's why it has plugins on it.

Thats a nice looking QJet! I didn't get rid of mine. I kept the original intake and carb and may have it rebuilt. At the least I'll keep it around for sentimental value.