Sbc 305?

[Seabee1989]

I have a 305 for my project, and i have a few parts for it. and i cant decide what carb to put on it. I have a Holley 750 CFM that came with it on the side. but that just seems a little bit on the overkill. Any suggestions? I haven't taken it apart yet, but the guy i got it from said it was a stroker. I plan on doing the rebuild soon, also any info on a good cam, i was looking at the thump'r cam?

 

[YBeNormal]

In my opinion the 750 would be over kill until you do the rebuild. I would suggest getting an edelbrock 1406 or 1405. Around 600 cfm only major difference is electric or manual choke. You can pick them up for around 50 to a 100 bucks all the time and then buy a rebuild online for 30 There are all sorts of YouTube videos how to rebuild adjust etc. and they are MUCH simpler to adjust than a Holley.

 

[Seabee1989]

Sweet, thanks! I will look into those.

 

[Old Iron]

What ever you do don't go overboard on the cam selection, you'll hate it.
A 2800 to 3000 stall converter would be a good choice also with a cam change.
That should scoot your roadster along quite nicely.

 

[Seabee1989]

For sure, I am going for a decent street rod that can hold its own. Sobi was looking at the regular thumpr cam. Also back on the carb. I just began pulling the motor apart a before I did I checked to see if that Holley 750 even would fit on the intake manifold....no go. It won't fit so I am looking for one of those edelbrock 600's you mentioned. Should I change the intake manifold, it sportin the stock gm manifold?

 

[Old Iron]

It's always nice to have an aluminum manifold under your carb [dr
I wouldn't go bigger than 600 cfm.

 

[YBeNormal]

For sure, I am going for a decent street rod that can hold its own. Sobi was looking at the regular thumpr cam. Also back on the carb. I just began pulling the motor apart a before I did I checked to see if that Holley 750 even would fit on the intake manifold....no go. It won't fit so I am looking for one of those edelbrock 600's you mentioned. Should I change the intake manifold, it sportin the stock gm manifold?

I'm sorry I assumed you had an aftermarket intake. The setup you have is probably just for a 2 barrel carb. I would suggest getting an aftermarket intake, there are alot out there. But an edelbrock performer can be picked up cheap just do a search for sbc intake. I am sure there is one close buy for sale cheap

 

[Seabee1989]

I'm sorry I assumed you had an aftermarket intake. The setup you have is probably just for a 2 barrel carb. I would suggest getting an aftermarket intake, there are alot out there. But an edelbrock performer can be picked up cheap just do a search for sbc intake. I am sure there is one close buy for sale cheap

well it's set up for a quadrajet, and I know that the stock intake was not very efficient. I was looking at the edelbrock performer and a edelbrock 600 cfm carb on ebay last night and i think that is what i am gonna go with. Now i havent spent to much time with 305's.( i have owned more small block Fords and SBC 350's.I know they are also not the most popular when it comes to building street cars and performers because they are more MPG friendly and what i have learned is real torquey, but it's what I got to work with, so my question is are the heads any good, the crankshaft, is this stuff that i should go aftermarket? or should i rebuild it stock, with a different cam, exhaust, intake?

I appreciate all of your advice ont this project

 

[Seabee1989]

I am looking at a 68 307, and wanting to know what everyone thinks, i am thinking about using the 307 block and pistons and possibly going with 350 crank and rods, and possibly using my 305 HO 416 Heads. is this something that would be worth doing? i am just thinking that the 305 is pretty limited because it is a 80's smog motor? any input would be helpful


Thanks

 

[Old Iron]

Almost all 307's can be bored to 4" which is standard for 327's and 350's
The 307 and 327 share the same crank and rods so at 4" bore and 327 pistons the 307 would now be a 327.
Bore it to 4" with a 350 crank and pistons it's a 350.
As far as the 305 heads goes, someone else will need to chime in cause, I've never used them.

 

[Seabee1989]

Okay, are my 416 heads useable for a 327, IMO the 416 heads would not be a good fit for a 350, would they work well on a 327? Also will the cylinder walls of 327 take that or will they be to thin?

 

[Old Iron]

If you're saying, will cylinder walls on the 307 be too thin, the answer is no.
The 307 is the same block as a 327. GM just done an under bore on those blocks.
And on the heads ? 416 or 461 ?
Not familiar with a 416 head.
If 461 then yes they work great. The only draw back is the 461 head doesn't have the accessory holes for alternator and power steering pump etc.

 

[sorj]

comparing the 305, 307, 327, and 350, The 305 is a good engine if you dont plan on trying to build ground pounder. My last S10 had the TPI 305 in it and it out ran many larger displacement engines. However, you have to remember, it is small journaled and are limited on what you can produce without spending a lot of $$$. Strangely enough, I ran a hi-po 350 cam in mine and it was excellant. The 305 will like less carburation such as a 600cfm (originally designed around the sbc). The 307 and 327 (small journal) will be the same as your 305 as far as building. The 327 will be a little more forgiving when building though. If you plan on building a ground pounder, look around for a 350. You will spend less money and end up with better results. Pound for pound, the amount of money you'll spend stroking a small journaled engine, you can spend less money building a 383 (for there are tons of these kits out there now) and have more bang for your buck. Of course, you may get lucky and find a 400 but the 350s are still plentiful in the salvage yards and still for a decent price (for your planning on building it anyways).

 

[Willowbilly3]

Correct me if I'm wrong but isn't the 305 a large journal? And only the last couple years of 327 were large journal like the 307. 1966 and earlier would be a small journal. And the 307 has the same bore as a 283 which means you'd have to bore it .125 to make it a 327 or 350. Kinda risky, when you consider 4 inch bore blocks are stacked like cordwood at the scrap yard why risk it.
It's been a long time since I messed with Chevys so I might be remembering wrong on some of this. A quick search should get the info.
BTW 305 HO heads are supposed to be a pretty good runner design with small combustion chambers. I knew some dirt trackers that had a 400 block, 350 crank with 6 inch rods and the HO heads. It was a tough car to beat on the track, torque curve as flat as a table top.