new parts and lost performance?

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mooncows said:
K so i might have found the problem but not sure. My new carb has 2 vacuum ports, and originally the dist vacuum was in the drivers side but ive read its supposed to go on the passanger port. Could this affect my performance?

No. You'd have to check which is which but usually you'll have at least one port that is full manifold vacuum and another that is timed vacuum.

Obviously full manifold vacuum means you have your highest vacuum at low throttle application and close to zero at full throttle.
However timed or ported vacuum is the exact opposite. You have zero vacuum at low throttle application and more vacuum at full throttle.

I know its been debated over and over on which is better. Personally I've tried them both and didn't notice much if any difference between the two.

You can experiment with it but it's not going to really gain you what you think it is.

Just remember power is in the heads. If the heads don't flow well, then whatever you bolt onto the engine isn't going to do as much as it could.

And as mentioned before, what were the weather conditions like between your best run and these new runs with the aftermarket stuff added? As in was it colder out with the better run?

You'll likely find out that the 305 is similar to the Olds 307 in terms of performance. Your not really going to see a whole of gain just by bolting on a few external items. You'll have to dig into it (heads, cam, etc.) before you'll really start to gain anything.

What distributor are you using? I'm assuming its an older vacuum advance HEI or some aftermarket piece? If its the stock CCC-HEI distributor then that's likely part of your problem.
 
well me and my dad kinda got a contest going on to see who can hit around 13 or 14 eat first with 600 a month cause its all we can afford. now i cant afford new heads, but would getting my current heads machined to increase CR and maby slapping in bigg valves help at all? or is it not worth whatever ill pay. I just got 2 months left and around $1200 to go from 16.5ish to about 14. any ideas?
 
Yeah.......
Sell the 305, add it to the $1200 and build a 350.
 
mooncows said:
well me and my dad kinda got a contest going on to see who can hit around 13 or 14 eat first with 600 a month cause its all we can afford. now i cant afford new heads, but would getting my current heads machined to increase CR and maby slapping in bigg valves help at all? or is it not worth whatever ill pay. I just got 2 months left and around $1200 to go from 16.5ish to about 14. any ideas?
u can find a used set of heads for 600 or less. i just ordered a elgin cam and lifter kit for 90 bucks from competition products and they got a few different ones to choose from. or u can do like me and use a 100 shot. its good for a sec. off ur 1/4 mile time. u can find a used kit for like 2 bills. but u need to invest in a timing light for sure.
 
mooncows said:
k so im looking at these vortec heads. what would need to be done to install them and are they worth it? http://edmonton.kijiji.ca/c-cars-vehicl ... Z209473842
those heads can make decent power but after you buy everything u gotta buy to make em work u might has well have got a cheap procomp or patriot set of heads. i got a set that i was gonna install but i would have spent an extra 400. they use center bolt valve covers. so u need a set of those. u need a vortec head specific manifold. and i was gonna use roller rockers but u need a set of narrow self aligning unless u machine the heads for guide plates and screw in studs which will cost more $$$. so if u buy those heads for 200 and put em together ur self. parts will run about another 200. and u gotta spend 400 to make em work. ur in 8 bills. for 8 bills if u go used u can get some heads and roller rockers. check our ur local machine shop i know the one here in town has used afrs and brodix that they sell anywhere from 600 to 900 hundred.
 
thank you everyone for helping me i really appreciate the advice. Im learning alot and these forums are very friendly. Last question. Should i just get my current heads machined for compression and maby rebuilt to increase a hair or two of intake/exhaust or just slap in some used ones from the store?
 
to save me some cash im rebuilding my own heads. and machining for compression can be tricky sometimes. depending on how much u machine them u will have to check pvc. sometimes the pushrod holes wont line up if u machine em to much so u got to oversize the pushrod holes. that happened to me cuz i told the shop to machine em to 64cc to a 58cc on some ford heads. and also if u machine em to much u will have to measure for correct length pushrods. all im gonna do to my stock heads are put new valves. springs. seals. reatainers and locks. i got a setup for 100 bucks. and im gonna do a home port job just to clean up the valve pockets and the runners. ill prob see a good 20 or 25 hp increase which aint bad. if u got a dremel u should try it.
 
Definitely need to set the timing with a light, I bet this will help a ton. Adding headers, a better exhaust, and a better induction system you can bump the timing up a few degrees and pick up some power. Also you should hook your vaccum advance up to the timed vaccum port ,it will bring in more timing as the vaccum goes up to help with mileage when you're out cruisin' down the highway. If you have the distributor hooked to the full vaccum it will pull alot of vaccum at all times, except when you floor it. When you floor it doesn't matter if it's hooked to the timed port or the full vaccum, there is no vaccum when you're wide open. Having it to full vaccum you will have alot of timing at idle, then when you mash it all of the vaccum is gone and so is your timing. Hooking up to the timed port will have little or no vaccum advance at idle and will bring it in as the rpm's go up under gradual acceleration. But definitely set the timing with a light and experiment a little by moving the timing up or down a couple degrees, then make a pass and try moving it again. I've seen some engines I've built pick up 10-15 horsepower on the dyno by moving the timing up 2 degrees and finding that sweet spot. Also going with a mild street cam can help to wake it up for cheap, but for $500-$1000 more you could upgrade to a 350 using parts off the 305 to save some money. Good luck hittin' the 13's.
 
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