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-   -   Not enough power! :) (https://67-72chevytrucks.com/vboard/showthread.php?t=357123)

oldblue1968chevy 08-10-2009 04:23 PM

Not enough power! :)
 
My truck feels really slow..what're some things(cheap/easy) i can do to help that? (without killing reliabilty)

Right now im running a stock 350 with a 3spd tranny (column).
stock air breather,4bbl qjet, but ive gotta edelbrock carb. i just rebuilt but its puttin gas in my oil so im running the q jet for now. and ive got glasspacks out back.

also its not tuned very well at all. (im bout to go play with carb./timing..what should my timing be set at also?

thanks

smoky02 08-10-2009 04:26 PM

Re: Not enough power! :)
 
advanced 10 degrees or so, depending on what feels good to you, you can also go a little higher than that, you just need to make sure to listen for some labor knocking or pinging if you advance it to much. you could also put a good sized K and N air filter on it. That may help some. I would also say if you want it to feel stronger that you should change the gearing in the rear.

oldblue1968chevy 08-10-2009 04:37 PM

Re: Not enough power! :)
 
ok
thanks
whatre your opinions on headers and intake mainfolds (bolt on stuff)

smoky02 08-10-2009 04:44 PM

Re: Not enough power! :)
 
I'm a fan of the edelbrock RPM intakes, and I'm also running hooker headers, but it's said that manifolds give you the best take off. Or low end torque.

capev86 08-10-2009 04:45 PM

Re: Not enough power! :)
 
best upgrade for a tired 350......rebuild it up to a 383. as efficient as a 350 but with more horsepower and especially more torque and throttle response. stroker motors should be a natural choice in a truck!

turp mcspray 08-10-2009 04:46 PM

Re: Not enough power! :)
 
What's the dizzy out of? It's probably got a lazy advance curve,especially if it's a stock HEI. Pick up an advance kit for about $5 and swap in some weaker springs. This will wake it up and is simple and cheap.
I've also preached it before...free up the exhaust FIRST. Trying to get more fuel and air in, won't do much good if it can't get out!

Shyguy 08-10-2009 05:07 PM

Re: Not enough power! :)
 
Some very good suggestions have be already given, but need to know more about your setup.

What gears do you have in the rear-end and what tire size.

Is it a short bed or long bed?

Quickest and cheapest fix will be a good tuneup including a K&N type air filter.

Some people hookup the vacuum advance to the lower part of the carb instead of ported.

I am running a stock 350 with tall tires and a 4 speed in my lwb '71 C-10 and have no problem lighting up the tires on take off.

Danny

oldblue1968chevy 08-10-2009 05:07 PM

Re: Not enough power! :)
 
ok i put it on 10 AFTER, which is apparently not what you ment, advanced must be 'BEFORE' on the harmonic balancer. ?correct?

ive got it at normal operating temp. and pluged the vacum...this iscorrect.??

'72customdeluxe 08-10-2009 05:09 PM

Re: Not enough power! :)
 
Your stock low compression 350 won't be "fast" without heads. But you might try some long tubes along with a Flowmaster dual 2.5" into single 3" y-pipe if you're after torque/off the line pep. If you just want the sound and looks of duals, go with 2.5" pipe and always use an x or H pipe. You posted your problems with the edlebrock before. Still don't know what putting fuel into the oil means. As in your oil smells like fuel?

'72customdeluxe 08-10-2009 05:11 PM

Re: Not enough power! :)
 
Advanced would be before. And always take off the vaccum advance line and plug it with a screw or something so you don't have a vacuum leak

oldblue1968chevy 08-10-2009 05:12 PM

Re: Not enough power! :)
 
it was a 'fresh rebuild' 7000 miles ago...

turp mcspray,all i know is that its an electronic ignition..tell me a lil moer bout the 'advanced kit'

free up the exhaust, ya mean go straight pipes or another type of exhaust lol, or ya talkin headers????

shyguy,i THINK i did it right awhile back and if i was correct (good chance im wrong though) it was 3:73

its a lwb

"Some people hookup the vacuum advance to the lower part of the carb instead of ported"

whats that mean...on the q jet its on the lower right hand side if yourl ookin at it, it goes to the dizzy.

THANK YOU GUYS SO MUCH KEEP THE HELP COMIN GOIN BACK OUTDIE

oldblue1968chevy 08-10-2009 05:25 PM

Re: Not enough power! :)
 
72CUSTOMDELUXE

well once it was my fuel pump, i had probably a quart of fuel in my oil and it smelled like gas, new fuel pump and oil change it was good...rebuild my edelbrock and i think it did it again just a lil, im takin it to a person thats supposed to be able to adjust carbs real good hes gonna play with it for me i think.

GOT MY TIMING SET TO 10 BEFORE AND IT RUNS ALOT BETTER! i have a little bit of a pinging on aceleration...which way do i need to go with it? im set at about 10.5 before.

oldblue1968chevy 08-10-2009 05:29 PM

Re: Not enough power! :)
 
so a good upgrade would be some long tube headers, K&N style air filter (?leave q jet or edelbrock?)

would going to flowmasters from glasspacks really be that much, im on a budget here...

and does an H or X pipe really help that much? how much $$ am i looking at spending for an exhaust shop to do an X or H pipe?

thanks as always! :)

'72customdeluxe 08-10-2009 05:41 PM

Re: Not enough power! :)
 
Glass packs to Flowmasters would be a downgrade in performance. What is your total exhaust set up? 2.25" duals with glasspacks and stock manifolds? You can get a universal x-pipe kit for 30 bucks, or have a shop do it. They're pretty cheap. If the edelbrock is still diluting your oil with fuel it seems like it's just rich. Go on edelbrock's website and there is a tuning guide. You can adjust alot on an edelbrock with a tachometer, vacuum guage, and screwdrivers. Don't waste your money on someone else tuning it. http://www.edelbrock.com/automotive_...all/1000.shtml The tuning guide is in there. It really helped the performance on my last truck with an edelbrock. Is it pinging at full throttle? just back off the timing a degree or two at a time until it stops. So go to 8 degrees or so before instead of 10

mclairmo 08-10-2009 05:44 PM

Re: Not enough power! :)
 
I would say to make sure that what you have there is working 100% and is all properly tuned up. Make sure you have a good clean open element air filter, new high flow fuel filter, new plugs, new wires, new cap and rotor, good fuel pump, no restrictions in the fuel line, etc. Make sure that the carb is working well and is nice and clean. Confirm that the jetting is correct and that you are not too lean or too rich. Make sure that you have full throttle operation. Often, the carb linkage is messed with and the throttle plates (not the choke plate) will not open all the way when you put the pedal to the floor. Make sure the secondaries open when you want them to open. Make sure your coil is not weak. Confirm that your exhaust is not restricted in some way by a kinked exhaust pipe or a closed and nonfunctioning hot air butterfly on the end of the exhaust manifold. If everything is 100%, then the combo you have should feel stronger than you describe, unless the engine is tired. Peform a compression test ane leak down test to confirm engine health. If rings/cylinders are worn, if valve guides are worn, if valves are burnt, nothing will help with that except a rebuild.

capev86 08-10-2009 06:35 PM

Re: Not enough power! :)
 
keeping with the stock ram horns are best if you want performance on a budget. the rest of the exhaust is where the big restriction is. i plan to keep the ram horns on my 72 burb when i swap out the stock 307 for a 406sbc and put my money into a stainless magnaflow dual exhaust w/ x pipe from lmc truck. headers don't last as long as the heavy cast iron pieces and most sacrifice low end power for high end horsepower. sorry...i don't want to compromise on the bottom end in a truck that is used as a truck and not a truck trying to ape a car.

another idea is to make sure the ignition is in top order (i recommend an electronic ignition conversion). my dad found out (after spending tons of money on a whole new hei distributor on his 87 suburban) that a little dialectric grease on all the ignition wire boots (both plug and distributor end) cured the total loss of power. every time the truck start running dull, he repacks all the wire boots and things are good to go again. hei is a bit different than the older tech, but i recommend this trick on any gm product....they are picky like that.....

mclairmo 08-11-2009 06:15 PM

Re: Not enough power! :)
 
I've also used the diaelectric grease and it works well to keep moisture out of everything and prevent corrosion. Tubes of it are expensive, though.

capev86 08-11-2009 07:59 PM

Re: Not enough power! :)
 
a few bucks for a tube of dialectic is much cheaper than spending $500 on a new hei distributor. it started acting the same way a few months after he got the truck back and then a mechanic friend of his put him onto the fact that gm's really like dialectic grease. when the truck starts running like it has a citroen 2cv engine under the hood, he re-greases the points and its like new for another year or so.

WorkinLonghorn 08-11-2009 08:12 PM

Re: Not enough power! :)
 
Quote:

My truck feels really slow
First question would be Is it smooth or is it "missing"? When you cup your hand over the exhaust is there a bup bup bup or is it pretty smooth with no large pulsations?
Next thing to check is the timing ADVANCE. Get a timing light and check that the timing advances as the RPMs go up.Also suck on the tube going to the distrib and watch to see if it advances.Or you can remove the distrib cap and watch to see if there is a slight rotation when you apply the suction.
Pull a plug or two and let us know what they look like ie.,sooty,white,oily tan,etc.

oldblue1968chevy 08-11-2009 08:46 PM

Re: Not enough power! :)
 
i'll pull a plug tomorow its raining and dark now....

thump thump thump is how the exhaust sounds.....

its set to about 10 advanced

havent checked timing with diff. rpms yet will do that tomorow

took my carb. to orielys today (edelbrock) and the guy tore it apart set floats looked it all over said i did good rebuilding it...bought a new gasket for it and was gonna put that and my tailgate back on tonite but i had geometry hw. well 2nd day of school i forgot my hw at school. so dads chewin me out telling me im iresponsible etc. so i didnt get carb on.

Plan for tomorow:
-put edelbrock on
-try to pick up dielectric grease
-pull some plugs and relay what i see to you guys.

turp mcspray 08-11-2009 09:09 PM

Re: Not enough power! :)
 
As far as exhaust...I am a firm believer in headers.On a mild engine like yours stay with 1 5/8" tubes. 1 1/2" would be better but not easy to find. Also a pair of good freeflowing mufflers. You can get a universal exhaust system from Summit or Jegs for less than $200. And it's mandurel bent instead of kinked. I would use no bigger than 2 1/2". I would try advancing the timing in 2 degree increments and then drive it WITHOUT the vacuum advance hooked up. Run as much timing as you can before it pings. THEN hook up the vacuum advance. If it pings on one source (full or ported vacuum) try the other. If it still pings on both, you need to limit the amount of vacuum advance.
An advance kit has different springs for the mechanical advance. Lighter springs (which is what you need) will allow your dizzy to advance sooner. Do some internet sourches on some of these board recomondations for more details. You have had a LOT of stuff thrown at you! Read, read, and read some more. Good luck on your search for more power. But be warned...it will NEVER end! LOL!!

'72customdeluxe 08-11-2009 10:33 PM

Re: Not enough power! :)
 
The flowtech/summit headers are 1.5" The summits are the same but in a white box for cheaper. 3" collectors on both

WorkinLonghorn 08-11-2009 11:43 PM

Re: Not enough power! :)
 
I wouldn't worry about buying a lot of new parts right now.
If the exhaust is going bup bup bup and not smooth like brrrrrrr,then it sounds like you have a "miss" which will DEFINATELY cause a loss of power!!!
Find the bad plug,bad plug wire,check distrib cap,maybe pull all the plugs and check the compression with a gauge. You need to find out why there is one cylider (at least) not pulling it's weight.

If I didn't have a compression gauge or an ohmmeter (to check the wires),I'd just make sure the cap was good and that all the wires were tight. Then I'd look at the plugs.

oldblue1968chevy 08-12-2009 06:35 PM

Re: Not enough power! :)
 
ok guys heres the news:

just got geometry done (all i knew how)

i put my edelbrock on when i got home from school..got it runnning need to buy new hoses tomorow after school allso....runs prety good...

im bout to go pull some plugs..should i pull them all? or just 1 or 2? im posting what i find on here....be back shortly...what should the wires read with an ohms meter?

mclairmo 08-12-2009 07:15 PM

Re: Not enough power! :)
 
Make sure that you keep school as your number one priority. Without en education, it will be pretty hard for you to earn the kinda money needed to finance this expensive hobby we all share. Good luck.


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