More Power
slavejay
04-27-2006, 12:39 AM
know this question has been posted THOUSANDS of times, but i want to know some CHEAP ways to increase power in the 85 with a 305 engine. i already have replacement exhaust (waiting for the cat then its getting put on ), any more ways to get more airflow?
silicon212
04-27-2006, 01:40 AM
know this question has been posted THOUSANDS of times, but i want to know some CHEAP ways to increase power in the 85 with a 305 engine. i already have replacement exhaust (waiting for the cat then its getting put on ), any more ways to get more airflow?
Fast, cheap, is good: Pick any two.
Sorry Charlie, there's no way you're going to make power with that engine without spending some dough, there's just no way around it. I've detailed methods on how to increase performance in another thread - but you have to do that to make it flow. Look, the 305 comes with small valves, a restrictive intake (on the LG4 - which your car has), restrictive exhaust, et. al. That's just the reality of it - there's no other way around that. It's an engine that's designed for economy, not performance. It was all about GM meeting CAFE requirements - nothing more and nothing less. In fact, CAFE is the reason why you didn't see a 350 in any stock Caprice/Impala B-body throughout the 80s unless it was a 9C1 - and even then a 350 isn't guaranteed.
You wanna make it go a little faster, you can help it a little bit (don't expect more than 1-2hp with this mod, it's up to you to determine if it's worth the cost) by replacing the exhaust manifolds with the under-spark-plug type as seen in earlier years (1977-1979 type) but make sure you get the ones with the bung for the EGO sensor (you will find these on trucks from the 80s and 90s). You will also need the Y-pipe that will fit those manifolds and your exhaust system (catalytic converter - again a 1977-79 should fit the bill). While by no means are these performance monsters, they are a little less restrictive than the "log" type that's on your car now. Larger primary exhaust will also help it breathe a little better.
If you want more power, then look at cam, valvesprings, rocker arms (1.6 ratio arms can help offset the smaller valves somewhat), intake, etc.
Go to Pick 'n Pull and grab yourself a complete 350 engine with all accessories for $99. Or else get prepared to spend some money. Or leave it alone and drive it like it is.
Fast, cheap, is good: Pick any two.
Sorry Charlie, there's no way you're going to make power with that engine without spending some dough, there's just no way around it. I've detailed methods on how to increase performance in another thread - but you have to do that to make it flow. Look, the 305 comes with small valves, a restrictive intake (on the LG4 - which your car has), restrictive exhaust, et. al. That's just the reality of it - there's no other way around that. It's an engine that's designed for economy, not performance. It was all about GM meeting CAFE requirements - nothing more and nothing less. In fact, CAFE is the reason why you didn't see a 350 in any stock Caprice/Impala B-body throughout the 80s unless it was a 9C1 - and even then a 350 isn't guaranteed.
You wanna make it go a little faster, you can help it a little bit (don't expect more than 1-2hp with this mod, it's up to you to determine if it's worth the cost) by replacing the exhaust manifolds with the under-spark-plug type as seen in earlier years (1977-1979 type) but make sure you get the ones with the bung for the EGO sensor (you will find these on trucks from the 80s and 90s). You will also need the Y-pipe that will fit those manifolds and your exhaust system (catalytic converter - again a 1977-79 should fit the bill). While by no means are these performance monsters, they are a little less restrictive than the "log" type that's on your car now. Larger primary exhaust will also help it breathe a little better.
If you want more power, then look at cam, valvesprings, rocker arms (1.6 ratio arms can help offset the smaller valves somewhat), intake, etc.
Go to Pick 'n Pull and grab yourself a complete 350 engine with all accessories for $99. Or else get prepared to spend some money. Or leave it alone and drive it like it is.
slavejay
04-27-2006, 02:43 AM
i'll probably just leave it alone and drive it like it is... i'm not looking for a race car or anythin too special with it , just wanted some cheap boost in performance if there was any, which im guessing there isnt. i love the way the car looks and how smooth it drives. and i love how girls always tell me how comfortable it is heh. on the highway, it has great pickup, running strong with the spedo maxed out. its a really well maintained engine, only 104,000 miles, so im definately not replacing the engine... not even an option at this point.
anyways, as far as speed goes, when i have the money to do it, ill just buy me a 69 camaro or wait til 2009 and get the new camaro (any opinions on how they look, i personally like them)
anyways, as far as speed goes, when i have the money to do it, ill just buy me a 69 camaro or wait til 2009 and get the new camaro (any opinions on how they look, i personally like them)
Blue Bowtie
04-27-2006, 01:59 PM
Pick up some used 14014416 head castings. Rework them like this:
http://72.19.213.157/files/416Heads.jpg
Using these templates:
http://72.19.213.157/files/416Templates.jpg
So you get a little better compression with your dished pistons. Install a Comp XE256H cam and lifters, free up the exhaust as silicon outlined, install a dual snorkel air cleaner from and F-Car L69 (or make your own) and tune the original Rochester carb. You should make more torque, more peak HP, and get just as good if not better fuel mileage. The whole exercise should cost you well under $700 if you do the work yourself.
http://72.19.213.157/files/416Heads.jpg
Using these templates:
http://72.19.213.157/files/416Templates.jpg
So you get a little better compression with your dished pistons. Install a Comp XE256H cam and lifters, free up the exhaust as silicon outlined, install a dual snorkel air cleaner from and F-Car L69 (or make your own) and tune the original Rochester carb. You should make more torque, more peak HP, and get just as good if not better fuel mileage. The whole exercise should cost you well under $700 if you do the work yourself.
slavejay
04-27-2006, 05:21 PM
heh, thanks for the photos of the head castings but all they did was confuse me, i dont have great knowlege or skills with cars, but im only 19.... but thanks a lot, ill show them to some of my friends and maybe they can explain to me and help me
silicon212
04-27-2006, 05:29 PM
i dont have great knowlege or skills with cars, but im only 19....
That shouldn't mean anything - when I was 19, I had almost every available head casting number for SB Chevy memorized ... anyways the heads he showed you above are high performance, high-flow heads for 305 that can take 1.94 (larger than factory) intake valves. I believe they also have 58cc chambers which means they're higher compression heads (higher compression = more power and better economy).
That shouldn't mean anything - when I was 19, I had almost every available head casting number for SB Chevy memorized ... anyways the heads he showed you above are high performance, high-flow heads for 305 that can take 1.94 (larger than factory) intake valves. I believe they also have 58cc chambers which means they're higher compression heads (higher compression = more power and better economy).
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