4 cylinder cosworth is the first thing that comes to mind.
Pretty simple, http://www.jegs.com/p/Chevrolet-Per...ci-300HP-Crate-Engine-Package/755609/10002/-1
If you are going to do a junk yard 350 may as well build a stroker out though. More bang for the buck IMHO.
I assume the 305 is still running just smoking?
Use the 305 heads way better than any 76cc head from the gm line from factory.
Toss them onto a 350 with 268H comp cam or lunati cam and have 350HP 350"
That same cam in a 305 with 9.5 compression and bowl porting will reward you with 300HP.
Bring me the 305 heads and I will show you how to port them.
Something else i experimented with on those GM iron heads was to open the pushrod pinch.
I ported a set and left the intake face and pinch alone. thinking smaller cross section on this particullar build would result in more MPG and i used a very small 260H cam.
MPG was not there my opened up runner heads and larger 268H got 4 MPG better.
Same everything except head intake runner and cam.
Yes the strokers will run circles around the 350. but you build a 383 and stick 76cc non ported heads on it and you got nuffin.
That engine in the jegs link is a terrible set up. cam with that duration and 8.0 compression.
I can see some sad low speed pulling power and probably not real good MPG.
I ran the 224@ .050 cam many times and it liked to swing to 6900 rpm with a conservative tune.
My 218@ .050 makes max HP at 5700RPM with 1.84-1.50 valves in 305 heads.
Will twist past 6500rpm lickity split.
Old engines are getting hard to come up with a good one.
Use the 305 heads way better than any 76cc head from the gm line from factory.
Toss them onto a 350 with 268H comp cam or lunati cam and have 350HP 350"
That same cam in a 305 with 9.5 compression and bowl porting will reward you with 300HP.
Bring me the 305 heads and I will show you how to port them.
Something else i experimented with on those GM iron heads was to open the pushrod pinch.
I ported a set and left the intake face and pinch alone. thinking smaller cross section on this particullar build would result in more MPG and i used a very small 260H cam.
MPG was not there my opened up runner heads and larger 268H got 4 MPG better.
Same everything except head intake runner and cam.
Yes the strokers will run circles around the 350. but you build a 383 and stick 76cc non ported heads on it and you got nuffin.
That engine in the jegs link is a terrible set up. cam with that duration and 8.0 compression.
I can see some sad low speed pulling power and probably not real good MPG.
I ran the 224@ .050 cam many times and it liked to swing to 6900 rpm with a conservative tune.
My 218@ .050 makes max HP at 5700RPM with 1.84-1.50 valves in 305 heads.
Will twist past 6500rpm lickity split.
Old engines are getting hard to come up with a good one.
9.5 to 1 is starting to increase the octane requirements though isn't it. Especially on those 100 degree plus days. I am all for high MPG's but when you have to start spending an extra 20 to 30 cents per gallon there are diminishing returns.
Just want to say that the link was a quick here you go. 300HP is simple to find. The question is how much time and money someone wants to throw at that 300HP to get there and what you expect to be able to do with it afterwards. Plus to go from a 305 to a 350 is already going to be a huge performance boost even without getting 300HP.
Just want to say that the link was a quick here you go. 300HP is simple to find. The question is how much time and money someone wants to throw at that 300HP to get there and what you expect to be able to do with it afterwards. Plus to go from a 305 to a 350 is already going to be a huge performance boost even without getting 300HP.
Even my 350 and 455 olds and buicks in stock low compression form ran much better on 91 octane.
I can pull timing back and run 87 with my 350's but I like to drive like i stole them.
The added compression is great for building low end TQ and very snappy throttle response.
I have my 350's at 10.87 actual compression I built one with 11.9 and it was happier than a 10.5 compression 350 I built with a larger cam.
The difference was the 54cc chamber of the high compression build was less detonation sensitive.
Most small chamber heads are ..This is why I like the 305 heads or take .060" off the old 64cc heads.
One better would be to run the 1996 vortec head it continued a few more years after 96 but it is a good power making head.
Excellent chamber and intake runner.. ex side sucks.. but that is to be expected.
300Hp is almost not worth building one. the 268H will make 375HP easy.
I want TQ and I want a lot of it everywhere. that is why I build them the way i do.
Yes sir 300HP is very simple to get in a 350"
And you are right the 350 will be a huge jump in power.
1978 305 with 2 barrel carb 145 HP at 3800 rpm 245 ft lbs torque at 2400 rpm.
1978 350 with 4 barrel carb 170 HP at 3800 rpm 270 ft lbs torque at 2400.
Those were dismal days.
I have got used to my 350's and have driven new trucks with the 5.3 lS and hate the lack of towing power.
I built a 327" 9.5 compression for my 47 dodge..disappointed is an under statement .
I just pulled a 385" stroker out of it with almost 12:1 compression . and the engine before that was a 350" with nearly 11:1
the 327 ran good from 4000-7500+ not worth a crap for a work truck.
So yea go cubes if it is heavy and you plan on working it.
The truck now is getting 355" the 327 will be mothballed for a while.
I can pull timing back and run 87 with my 350's but I like to drive like i stole them.
The added compression is great for building low end TQ and very snappy throttle response.
I have my 350's at 10.87 actual compression I built one with 11.9 and it was happier than a 10.5 compression 350 I built with a larger cam.
The difference was the 54cc chamber of the high compression build was less detonation sensitive.
Most small chamber heads are ..This is why I like the 305 heads or take .060" off the old 64cc heads.
One better would be to run the 1996 vortec head it continued a few more years after 96 but it is a good power making head.
Excellent chamber and intake runner.. ex side sucks.. but that is to be expected.
300Hp is almost not worth building one. the 268H will make 375HP easy.
I want TQ and I want a lot of it everywhere. that is why I build them the way i do.
Yes sir 300HP is very simple to get in a 350"
And you are right the 350 will be a huge jump in power.
1978 305 with 2 barrel carb 145 HP at 3800 rpm 245 ft lbs torque at 2400 rpm.
1978 350 with 4 barrel carb 170 HP at 3800 rpm 270 ft lbs torque at 2400.
Those were dismal days.
I have got used to my 350's and have driven new trucks with the 5.3 lS and hate the lack of towing power.
I built a 327" 9.5 compression for my 47 dodge..disappointed is an under statement .
I just pulled a 385" stroker out of it with almost 12:1 compression . and the engine before that was a 350" with nearly 11:1
the 327 ran good from 4000-7500+ not worth a crap for a work truck.
So yea go cubes if it is heavy and you plan on working it.
The truck now is getting 355" the 327 will be mothballed for a while.
You interested in a 425 Cadillac then. I know where one is at and own it, the problem is it has an RV wrapped around it and the guy who was supposed to pay me for it blew a seal.
Had a 350 in it and the owner before me was told to put this engine in it for more torque. Fine and dandy but it shifts into top gear at 15MPH and at 45 it burns fuel like you have a hole in the tank. I have needed to do something with it but honestly I don't want anything else to do with it.
Had a 350 in it and the owner before me was told to put this engine in it for more torque. Fine and dandy but it shifts into top gear at 15MPH and at 45 it burns fuel like you have a hole in the tank. I have needed to do something with it but honestly I don't want anything else to do with it.
Well I think that the upgrade is doing pretty good so far. Was running 70 to 75mph most of the time the last couple days and put 775 miles on the truck. Used 39 gallons so got about 19.5mpg when the truck was rated at 18mpg which is generally done at much lower speeds. Still had a backseat full of stuff and a toolbox and some ramps plus gas cans in the back end so I am happy. Usually don't do that well except for when I am heading to Peoria AZ from Albuquerque via Payson which is about 430 miles on a tank of 24 gallons or just under 18mpg. I am very happy with how things are going and if I can get a heat exchanger made up and see what that does.
I've got a flat plate heat exchanger your welcome to. Used it on a Dodge running WVO straight. You may need to clean the chicken guts out of the fuel side.
Sounds good, will have to figure something out when the wife gets out of the hospital. Been running around dealing with a ton of stuff since Thursday and probably be a few more days at least till she is out.
Just let me know. I'm all over the metro.
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