Chevy 350 or 305

[megaladon6]

hell, i think the biggest reason the g-bodies weren't really considered muscle cars was the 305. car guys will build anything they can get their hands on if there's any potential, the 305 just doesn't have it. and it's not just size as the GN has a 3.8l and it is considered a muscle car.

 

[83cut350chev]

and if u take the 2,000 you put in the 305 and put it in a 350....

 

[Phoenyx]

Re: 305

The most misunderstood engine in the Chevy small block family. Just check any forum, when the subject of building a 305 is presented, the reply is almost ALWAYS "build a 350" Heres my take on that, DONE, I GET IT, by using the "bigger is better" logic, we all must build a Hemi. Now lets move on to the 305. I've done a LOT of research and the result is as follows.

First to produce 400HP in a V8 you need to move 500+ CFM @ 100VE. Thats all. In stock form a 305 moves 431 CFM @ 6000 (assumed VE = 80) If we modify the intake/heads/exhaust to get as close as we can to 100 VE and bore it .020 over (now cid = 311) we will move around 539. @ 6000

With 1 hp for every 1.3 cfm, we have a potential of 414hp

The following combination, properly prepared, will do just that

1989 LB9 roller block .020 over 9.3cr

081 Heads, stock 1.84" valve flow 201.8 @ .40 lift with minor port work

Performer manifold

long tube headers, wraped

Stock LB9 cam Lift .415/.430 Duration 207/213 Sep 117 (non auto LB9 f body cam)

Dual roller chain

600 cfm carb

Performer manifold

Roller 1.5 rockers

HE ignition

Timing adjusted for 36 total advance (sb about 8-12 @ idle depending on the distributor set up)

I estimate the build will cost about $2,000 give or take, including machine costs.

I'll be building this engine next month and will post the step by step build, parts list with cost, and dyno results in late August.

I think you need to ventilate your work area better.

 

[82355supreme]

Re: 305

The most misunderstood engine in the Chevy small block family. Just check any forum, when the subject of building a 305 is presented, the reply is almost ALWAYS "build a 350" Heres my take on that, DONE, I GET IT, by using the "bigger is better" logic, we all must build a Hemi. Now lets move on to the 305. I've done a LOT of research and the result is as follows.

First to produce 400HP in a V8 you need to move 500+ CFM @ 100VE. Thats all. In stock form a 305 moves 431 CFM @ 6000 (assumed VE = 80) If we modify the intake/heads/exhaust to get as close as we can to 100 VE and bore it .020 over (now cid = 311) we will move around 539. @ 6000

With 1 hp for every 1.3 cfm, we have a potential of 414hp

The following combination, properly prepared, will do just that

1989 LB9 roller block .020 over 9.3cr

081 Heads, stock 1.84" valve flow 201.8 @ .40 lift with minor port work

Performer manifold

long tube headers, wraped

Stock LB9 cam Lift .415/.430 Duration 207/213 Sep 117 (non auto LB9 f body cam)

Dual roller chain

600 cfm carb

Performer manifold

Roller 1.5 rockers

HE ignition

Timing adjusted for 36 total advance (sb about 8-12 @ idle depending on the distributor set up)

I estimate the build will cost about $2,000 give or take, including machine costs.

I'll be building this engine next month and will post the step by step build, parts list with cost, and dyno results in late August.

I think you need to ventilate your work area better.

Agreed!! a 305 with stock heads & a tiny cam.... 400 ponies. Dream on.

The combo on my Cutlass I just sold had a 355 with DART heads, RPM AIR-GAP intake, 650 DP, 38* timing, 9.5:1 & a .498 lift/ 230* cam was just shy of 400 HP.

Maybe you forgot to mention the 100 HP shot of smack your gonna give it to achieve 400 horse.

 

[blizack]

What do you plan to do with the car?

I think when choosing which engine to use you should think of it like this: the 305 has a lower potential than the bigger engines so if you want to spend under $300-600 then keep the 305, but if you're planning on spending more than that, it would make sense to get a bigger engine.

If you're not planning on racing or anything like that, then maybe you should consider the upgrades like dual exhaust and headers, upgrade the ignition system, and maybe an intake. like the guys said, a bigger engine will give better value per dollar on upgrades, but why do you need that if you're going to the grocery store?

 

[1985Diablo]

He He He, I knew it, anyway, I'm building it, when the dyno results are in, then we can talk. Oh by the way, not using a stock cam, you are right, won't give enough. Still working on the specs. Tell ya all what, IF I get it right, won't you all feel silly?

 

[megaladon6]

well if you make it on the STATED spec, we will all be amazed.
if you change specs enough then you could make 400. forced induction, NO2, 10k rpm's will all get you there. but you'd still do it cheaper with a 350. sh*t, look at ferrari, they run 5L V12's at 9k rpms and only make something like 500hp. and their engines are a much better design than the 305. hell, than any chevy engine.

 

[custom442]

He He He, I knew it, anyway, I'm building it, when the dyno results are in, then we can talk. Oh by the way, not using a stock cam, you are right, won't give enough. Still working on the specs. Tell ya all what, IF I get it right, won't you all feel silly?

no, because I'll have around 450 hp/tq outta my 383, and then I'll throw a 75 shot on and it'll be the same price as your built 305. Who's feeling silly now?

 

[SScamino]

no you wont make that with 2000 dollars. This is my official guess for the power of your engine 250 horsepower, And thats because even though numbers say one thing doesnt mean its true, look its just not happening with that cam and those heads and that manifold. with my old 305 it was bored .30 thats 311 cubic inches. I put a performer manifold and 600cfm performer carb. Then put headers, 2 1/2 exhaust with turbo mufflers. From there it had a cam one step over stock. I put 1.6 rockers on it all with 416s with 1.84/1.5 valves 58cc chamber 9.0 compression. Guess how much it was? i bet it was 280 at the flywheel. It was pretty slow but had some get and go to it but Probably cause of my 3.73s.

 

[1985Diablo]

CAM

OK so, this seems to be the correct cam, any thoughts?

comp cams 08-412-8

Operating Range: 1200-5200 RPM
Duration Advertised: 264° Intake / 270° Exhaust
Duration @ .050'' Lift: 212° Intake / 218° Exhaust
Valve Lift w/1.5 Rockers: .487'' Intake / .495'' Exhaust
Lobe Separation Angle: 110°