305 heads on a 350?
Thread Starter
Senior Member
Joined: Jul 2007
Posts: 309
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From: Montana
Car: 91 Camaro RS
Engine: 350
Transmission: T56
305 heads on a 350?
I thought I might ask on here, two of my friends were talking about 305 heads on a 350. one friend wants to go looking into it and do research and wants to do it to his 350, and the other has already done it to his car, but he wont tell us much about it.
I started getting a little curious about this, because I need a project to work at shop class to where the school I go to. (I got a class where I can work on anything I want for a grade)
well, I want to know how it would be like on a 350, and if I ported them as much as I can but to where they will last.
Would I get more horsepower and torque over my 350 TBI iron cylinder heads I have on my 350?
and how much higher compression would I get out of it?
Would I have to do anything to my engine so it can handle the higher compression?
anything else I need to know about it?
I still have my 305 I took out of my camaro, its not the HO engine, but I thought if I take that apart, and if the heads are still good, I thought I could port them out and put them on my engine, and hope to get my horsepower and torque out of it.
Thanks.
I started getting a little curious about this, because I need a project to work at shop class to where the school I go to. (I got a class where I can work on anything I want for a grade)
well, I want to know how it would be like on a 350, and if I ported them as much as I can but to where they will last.
Would I get more horsepower and torque over my 350 TBI iron cylinder heads I have on my 350?
and how much higher compression would I get out of it?
Would I have to do anything to my engine so it can handle the higher compression?
anything else I need to know about it?
I still have my 305 I took out of my camaro, its not the HO engine, but I thought if I take that apart, and if the heads are still good, I thought I could port them out and put them on my engine, and hope to get my horsepower and torque out of it.
Thanks.
Junior Member
Joined: Nov 2007
Posts: 94
Likes: 0
From: illinois
Car: 86' Z28
Engine: 5.0l w/ new cam
Transmission: TH-350
Axle/Gears: 4.10's
Re: 305 heads on a 350?
I too have been debating using my 305 heads on a 350. I know some people have seen good results from them. i wouldnt use the ones from your tbi 305 though. they are the swirl port boat anchor heads. try and find ones of a tpi motor or the H.O. 305 if your dead set on 305 heads. what kind of 350 short block are you running?
Joined: Jul 1999
Posts: 10,950
Likes: 26
From: Orange, SoCal
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
Re: 305 heads on a 350?
Yes 305 heads have smaller combustion chambers which will give you a higher compression ratio on a 350 block. However, they also have smaller intake valves and smaller intake runners which will cancel out and restrict any power gain you would get from the higher compression ratio. Not to mention you'll could get more knocking and pinging as well. Its not a good idea.
Member
Joined: Nov 2007
Posts: 115
Likes: 0
From: parma,OH
Car: 91 camaro RS
Engine: 350, forged 355 in the works
Transmission: 4 speed goin to th400
Axle/Gears: stock 9bolt, 3.27
Re: 305 heads on a 350?
i had them on my 350, 5speed,
was good just for burning tires but for the long haul, was not worth it the car fell face first after 4500-5000 rpm, only thing good was torque,
i got a set of 350 vortecs iff your lookin for great heads. just pm me
was good just for burning tires but for the long haul, was not worth it the car fell face first after 4500-5000 rpm, only thing good was torque,
i got a set of 350 vortecs iff your lookin for great heads. just pm me
Thread Starter
Senior Member
Joined: Jul 2007
Posts: 309
Likes: 0
From: Montana
Car: 91 Camaro RS
Engine: 350
Transmission: T56
Re: 305 heads on a 350?
Yeah, I still haven't looked at the numbers on the heads I have, I probably wont use them. I am looking for more torque than horsepower really. (right now its a hydraulic roller, 4 bolt main block with Iron TBI heads with a dual plane intake with a 670cfm carb. getting 360 hp and 380 tq.)
I kinda made a decision that I want it to be more of a car that gets from point A to point B quicker, and burn tires (already does, but its a one wheel peal, just an open 10 bolt rear end)
and my 6 speed transmission I bought here two summers ago, 5th gear doesn't work (didn't work from the first when I bought it, I was pissed when I found out it didn't work, I think the person who rebuilt it (the owner said it only had 4,000 miles on it since it got rebuilt) either 5 gear is grinded down, or its out of adjustment.)
So I only have the first 4 gears to go then I drop it in 6 gear and it really kills the car, so I don't really care for top speed anyway, I do want to go for 4.56 ring and pinion gears in the rear end if I ever rebuild it or go for a different rear end.
My plan is I want to turn it into a street legal but a car I can take it to the strip to play with.
I do however want to get the transmission rebuilt eventually, but I figure all together with all the new parts I want to supply and the aluminum flywheel and clutch would be around roughly $2500, with out the labor of having some one rebuild it for me (which I don't know how much, and no one around where I live will touch a 6 speed transmission)
So the heads is something kinda minor on my list, and I don't really need to do anything to the engine right now, since the engine and everything in the engine is brand new, I just wanted to get a better understanding about 305 heads, or what kind of heads are pretty good to use for what I have.
and my friend is talking about putting 305 heads on his gm good wrench engine he has in his red camaro, and he's been looking up on information on it too. I think he may do it, but Idk if I will, I just like the idea of buying something brand new off JEGS or even on summit, to know I am getting good quality parts instead of buying some one Else's parts which are used (I have a problem buying used stuff)
It really bothered me that I bought my 6 speed transmission when I payed $2,400 for it and later the summer when me and my father put in the transmission and the new 350, and finding out the 5th gear doesn't even work.
If I had a choice and the money, I would of rather bought a new transmission off JEGS so I know it would work, and wouldn't have any problems with it.
And who knows, I may later want to get a different engine instead of a 350, I might wanna go for a 383 or even a 400 instead. I do know that I want to keep my 6 speed transmission, but want to get it rebuilt and new flywheel and clutch, and I might just beef up my 10 bolt, putting in all new and stronger parts in it and weld around the axle tubes like I read in the article on the tech articles on TGO.
I know these wont happen any time soon, I am trying to pay off a new truck I just bought for college, and Im still in highschool, but I do work everyday, and I am capable of putting some money into the camaro while paying off the truck.
So these plans may change eventually.
:-/
I kinda made a decision that I want it to be more of a car that gets from point A to point B quicker, and burn tires (already does, but its a one wheel peal, just an open 10 bolt rear end)
and my 6 speed transmission I bought here two summers ago, 5th gear doesn't work (didn't work from the first when I bought it, I was pissed when I found out it didn't work, I think the person who rebuilt it (the owner said it only had 4,000 miles on it since it got rebuilt) either 5 gear is grinded down, or its out of adjustment.)
So I only have the first 4 gears to go then I drop it in 6 gear and it really kills the car, so I don't really care for top speed anyway, I do want to go for 4.56 ring and pinion gears in the rear end if I ever rebuild it or go for a different rear end.
My plan is I want to turn it into a street legal but a car I can take it to the strip to play with.
I do however want to get the transmission rebuilt eventually, but I figure all together with all the new parts I want to supply and the aluminum flywheel and clutch would be around roughly $2500, with out the labor of having some one rebuild it for me (which I don't know how much, and no one around where I live will touch a 6 speed transmission)
So the heads is something kinda minor on my list, and I don't really need to do anything to the engine right now, since the engine and everything in the engine is brand new, I just wanted to get a better understanding about 305 heads, or what kind of heads are pretty good to use for what I have.
and my friend is talking about putting 305 heads on his gm good wrench engine he has in his red camaro, and he's been looking up on information on it too. I think he may do it, but Idk if I will, I just like the idea of buying something brand new off JEGS or even on summit, to know I am getting good quality parts instead of buying some one Else's parts which are used (I have a problem buying used stuff)
It really bothered me that I bought my 6 speed transmission when I payed $2,400 for it and later the summer when me and my father put in the transmission and the new 350, and finding out the 5th gear doesn't even work.
If I had a choice and the money, I would of rather bought a new transmission off JEGS so I know it would work, and wouldn't have any problems with it.
And who knows, I may later want to get a different engine instead of a 350, I might wanna go for a 383 or even a 400 instead. I do know that I want to keep my 6 speed transmission, but want to get it rebuilt and new flywheel and clutch, and I might just beef up my 10 bolt, putting in all new and stronger parts in it and weld around the axle tubes like I read in the article on the tech articles on TGO.
I know these wont happen any time soon, I am trying to pay off a new truck I just bought for college, and Im still in highschool, but I do work everyday, and I am capable of putting some money into the camaro while paying off the truck.
So these plans may change eventually.
:-/
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