Gonna rebuild my 305 TBI coverting to carb...head question
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Gonna rebuild my 305 TBI coverting to carb...head question
hey guys,
ok, now before the guys that say get a 350...please don't say anything. I know it would be better and make more power and blah blah blah. Truth is it is going to be cheaper for me here to rebuild my motor. I live on the big island of Hawaii and guys here love the 350 as much as the rest of us...so you know what that means...NO SUPPLY!!! And the guys that have them want a lot for it. Then there's shipping to buy from other places...so yeah...cheaper for me to go 305...ANYWAYS
I know that 350 heads have larger chamber sizes...305 i believe is 58cc usually? and 350's have 64-72cc. Now if i rebuild my 305 and put to 350 heads...how much does it lower the compression? i was thinking that i would just rebuild it with higher compression forged pistons to compensate. Figure that I want a ratio of 9:1 with the 350 head...i was thinking S/R Torquers 64cc's...what piston ratio would i need? I wanted the lower compression for now because i plan to setup either a blower or turbo later. i am converting it to carb though. i didn't want to go lower than 9:1 because i would like it to have "some" power...haha. i haven't decided on a cam either so any help with that would be appreciated as well.
ok, now before the guys that say get a 350...please don't say anything. I know it would be better and make more power and blah blah blah. Truth is it is going to be cheaper for me here to rebuild my motor. I live on the big island of Hawaii and guys here love the 350 as much as the rest of us...so you know what that means...NO SUPPLY!!! And the guys that have them want a lot for it. Then there's shipping to buy from other places...so yeah...cheaper for me to go 305...ANYWAYS
I know that 350 heads have larger chamber sizes...305 i believe is 58cc usually? and 350's have 64-72cc. Now if i rebuild my 305 and put to 350 heads...how much does it lower the compression? i was thinking that i would just rebuild it with higher compression forged pistons to compensate. Figure that I want a ratio of 9:1 with the 350 head...i was thinking S/R Torquers 64cc's...what piston ratio would i need? I wanted the lower compression for now because i plan to setup either a blower or turbo later. i am converting it to carb though. i didn't want to go lower than 9:1 because i would like it to have "some" power...haha. i haven't decided on a cam either so any help with that would be appreciated as well.
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Car: 91 RS
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Re: Gonna rebuild my 305 TBI coverting to carb...head question
well i think 9:1 even with 64cc heads which will cost just as much as 58cc heads will require a domed piston how much dome? you need to do the math for that one... if your gonna buy heads do you plan on buying new? $700 a pair sound about right? if you dont plan on going new you could always look at the 305 vortecs with 58cc chambers...
but if you plan on going blower or turbo 9:1 probably wouldnt leave you much room to grow depending on your set up but then again it is a 305 so i would think 8.5 would be out of the question N/a ... dont think you would want to run dome pistons with a blower or turbo anyway they have a higher tendency to detonate dished are the safest for forced induction you def want forged for any forced induction especially your first build
now cams you should be picking very last after you have decided which heads which intake and which type of forced induction as thier are different needs for both turbo and S/c
id say if you are dead set on a forced induction engine get a blower and drop the cr to 8.5 wouldnt be that big of a deal compaired to a turbo on a 305 with 8.5:1 you would be able to get more power out of 8.5 cr then the 9:1
but dont forget cam timing will play a big roll in all of this and needs to be considered as part of the whole and not a seprate part
but if you plan on going blower or turbo 9:1 probably wouldnt leave you much room to grow depending on your set up but then again it is a 305 so i would think 8.5 would be out of the question N/a ... dont think you would want to run dome pistons with a blower or turbo anyway they have a higher tendency to detonate dished are the safest for forced induction you def want forged for any forced induction especially your first build
now cams you should be picking very last after you have decided which heads which intake and which type of forced induction as thier are different needs for both turbo and S/c
id say if you are dead set on a forced induction engine get a blower and drop the cr to 8.5 wouldnt be that big of a deal compaired to a turbo on a 305 with 8.5:1 you would be able to get more power out of 8.5 cr then the 9:1
but dont forget cam timing will play a big roll in all of this and needs to be considered as part of the whole and not a seprate part
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