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[thewickedjester]

alright, i finnally got done rebuilding the engine in my truck. a little 305 SB Chevy in a big '86 GMC Sierra 1500 (i wanted to drop a 454 in it, but couldnt find one cheap enough, then gas prices really started to shoot up, so i scraped that plan and kept the stock engine). its faded blue, and looks like shit. although the engine runs good and the exhaust i had put on it sounds really badass, despite the fact that it has a rear main seal leak (of which sb chevy's are notorious for). heres my delema: it has the excelleration of a retarded turtle. granted i havent mounted the transmision kickdown yet, but what can i do thats cheap to give it a little more power off the line?

i know its a truck and all, and im not trying to make it into a drag racer or anything, but you got to understand, this things acceleration is REALLY SLOW. like old-lady-in-a-huge-buick slow.

[thesideinguy]

does it smoke alot when you try to accel hard?
does it have a 2 barel carb instead of a 4?
is it geting plenty of voltage?
hos the inside of your distributer look?
have you tried beating the shit out of your cats to see if they maybe almost clogged up?

[StrictPuppet]

Check your base ignition timing, you could set it up to 'bout 12 degrees, also make sure that the mechanical advance weights are not seized, to do this remove your distributor cap and twist the rotor with your hand. It should move bout 20 degrees or so then spring back when you let go.  If it doesnt, remove the rotor and make sure the weights are not overlapping and the springs are intact( if this doesnt make sense it will when you look @ it).  Also as stated above check your cat(if so equipped) 1986 should be a pellet style cat(huge ass pancake thing) they generally dont plug solid like a honeycomb style but could be your problem.  If it has been replaced with an aftermarket honey comb style cat, give it a good hit with a rubber hammer or your fist and listen for a rattle.  If it sounds like a golf ball in a coffee can the substrate has separated from the shell and can rotate and restrict exhaust flow...

[thewickedjester]

 (shh)


im gonna try advancing the timing a little bit, should give a bit more on the low end, although it will hurt my gas consumption a bit, but with such a small motor i dont think it will matter.

also, i found another issue with the carb. i think its tuned pretty well, but while im driving, if i make a sudden stop (quick stop, like the light turns yellow and i have JSUT BARELY enough room to stop) then the truck tries to stall. i think this might be because the transmission kickdown cable isnt yet attached and therefore the transmission is in to high a gear because it wont downshift quickly enough (so im going to look into a shift kit also). but could anything else be causing it to do this?

(edit) puppet: yeah, the distributors fine, we checked it when we first started it because we thought we had no spark (ended up being that my dad put the dist. in a 180 degrees backwards)

[thesideinguy]

it should stop smokin pretty soonif not already. it dosnt take too long for the rings to seat.
pay atention to the color of smoke also.

you are useing a timeing light right?

i would try adjusting the carb alitle and check your vac lines.

also, sence you just rebuilt your engin, have you re-torque the head bolts?

[thewickedjester]

yeah, it only smokes a bit when i start it

as far as me and my dad know, but he's done a ton of cars so i trust him

im gonna take it to a freind who is supposed to be THE MAN at tuning carbs, then we will see

you mean since we started it? no, didnt know i was supposed to, ill do it if you think that could be causing a problem. and the vacuum is good on all the lines

[thesideinguy]

dont know quit qhat you mean in that last sentence unless you refering to what i said about re-torqueing the bolts on the heads.
the deal with that is your sopose to re-torque them after about 50 miles after you rebiuld an engin, unless you boght gaskets that specificaly say you dont have to re-torque.

you posted that your dad put the distibuter in 180 deg out the first time.
when yall put it in the second time was the #1 cylinder at top dead center?

and i would doble check your plug wires to see if their in the corect fireing order.

[mynuffinfutsitch]

) for some good power and noise (after you get the timing right)