305 rebuild with performance parts

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Connor C

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Yeah I can see where you are coming from there with the weight. I understand that a 350 has the upper hand on a 305, but I could care less. The whole point of this was to get advice on building a 305 not doing a swap. It's already pretty hard to find anything even on other forums because people can't get past the endless responses saying to swap.
 

Schurkey

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What ever man, You clearly didn't read what I said originally.
Fifteen sentences of reply, one sentence of basic truth. The only one YOU read was the last one.

I know a 350 will make more than a 305 thats common knowledge. I've read so many forums where everyone just says to drop the 305. Someone who has experience with 305's and willing to share positive info is welcome, not someone here just to make snarky comments and talk ****. sorry
So you acknowledge that the Wisdom of the Multitudes is exactly what I said. That's a start.




WE'RE ALL VOLUNTEERS HERE. You don't get to dictate what I say. You don't get to dictate what anyone else says, either.
 

Connor C

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What are you even saying now? You gave what advice you had and then ended it by saying shitcan the engine, why even make a comment if that's what you think. You just couldn't hold back from saying it's a ****** choice. No I don't dictate what you say obviously, freedom of speech, I just asked that people refrain from either talking down on the 305 or telling me to swap it out because I wanted advice solely on a 305. I've already gone down the road of the 350 swap and what I would need to do, now I want to weigh my options with what I already have.
 

Hipster

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Yeah I can see where you are coming from there with the weight. I understand that a 350 has the upper hand on a 305, but I could care less. The whole point of this was to get advice on building a 305 not doing a swap. It's already pretty hard to find anything even on other forums because people can't get past the endless responses saying to swap.

When you sit down and figure up the sum of the parts and the time involved, instead of just talking about it, to get 350 like performance from a 305 compared to a 350 drop in the light bulb will come on.
 
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Connor C

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Does anyone else have any experience building a 305 and what you did. My apologies for earlier I kinda veered off course there for a bit with the 305 - 350 debate, sorry. So what are some heads that would be good? I've heard the 416 and 601 factory units are pretty good, someone mention vortec earlier or sprint car heads. Also what would an 081 casting be? I thought they were vortec but now it sounds like they may be different.
 

89GMCJOHN

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I think what you need to do is figure out your performance goal then put together the parts to get there . I think you said you wanted 300 hp from your 305 .

Like I said earlier I think a 268HR cam will get you to 300 hp - your goal.

Shoot for 10:1 properly gasket-ed and run a slightly cooler 180 tstat .

Any decent N O N TBI head with a 1.94 intake and around a 56 cc chamber should get you the flow you need for 300 hp. Look on ebay for cheaper rebuilt iron heads that can handle up to .500 lift or under .

Shorty headers , a better Y pipe and any cheap freer flowing chambered or dynomax type straight through muffler will get you that 300.

I have built 3 305's ....I heard it all too- dont build that 305 yada yada ...build whatever you want but alot of guys here are telling you the truth to go 350 ..dont hate - the reason is they are a dime a dozen, short blocks and crate motors are cheap and they will put out more power and bang for your buck and the resale on your truck WILL be higher with the 350 which is something to think about. Peace and good luck . FWIW .
 

Connor C

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thats great, Do you think keeping a y pipe affects it negatively or would dual's be better? I like the idea of using iron heads being cheaper than buying aluminum which add up really quick. I also see where you are coming from with 350s being dime a dozen. I would have to find a used one if I do go that route since crate engines prices are ridiculous in Canada. Earlier on I was looking at the 350/290 crate and the cheapest I could it in Canada was $3800, but I don't know if i really like that engine anyway.
 

89GMCJOHN

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thats great, Do you think keeping a y pipe affects it negatively or would dual's be better? I like the idea of using iron heads being cheaper than buying aluminum which add up really quick. I also see where you are coming from with 350s being dime a dozen. I would have to find a used one if I do go that route since crate engines prices are ridiculous in Canada. Earlier on I was looking at the 350/290 crate and the cheapest I could it in Canada was $3800, but I don't know if i really like that engine anyway.

At the 300 hp level a good aftermarket Y pipe vs duals isnt really a concern there is no HUGE gain going duals on a 300 hp build....your good with either , I would never spend the money on aluminum heads for a 305. A 350 yes. I get it your in Canada so things are expensive . Good Luck .
 

98 Nitro

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Your best bet is to just buy a set of 305 Vortec heads. They outflow any other 305 head, really any stock chevy heads other than 350 Vortecs or maybe 2.02/1.6 heads like the 492s I have in my garage. They are basically Tbi heads done correctly. 305 Vortecs make more hp than 350 Tbis. With those heads you will also need an intake like GMs Vortec Carb intake, plus an adapter for Tbi like the one GM used on big block Tbis that had spread bore intakes. Lunati's smallest Voodoo cam was made for small bore engines or Tbi engines go with that too. Then tune.
 
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