Engine Upgrade
Thread Starter
Intermediate
Joined: Jul 2007
Posts: 45
Likes: 0
From: Stevens Point WI
Engine Upgrade
Hey Everyone,
I have a 1985 Corvette with the stock 350 in it right now. I'm looking at doing an overhaul/upgrade to the engine itself. Just in the research stages of what parts I should get and which ones to stay away from.
I'm currently considering buying a new block and then doing all the upgrades to that so I can keep the vette on the road while I work on the upgrade.
Any tips, tricks and suggestions would be greatly appreciated.
Thanks!
Vision
I have a 1985 Corvette with the stock 350 in it right now. I'm looking at doing an overhaul/upgrade to the engine itself. Just in the research stages of what parts I should get and which ones to stay away from.
I'm currently considering buying a new block and then doing all the upgrades to that so I can keep the vette on the road while I work on the upgrade.
Any tips, tricks and suggestions would be greatly appreciated.
Thanks!
Vision
Thread Starter
Intermediate
Joined: Jul 2007
Posts: 45
Likes: 0
From: Stevens Point WI
Not sure yet. Just starting out on my research so I'm looking for all the pro's and con's. Whatever will get me the most bang for my buck while still keeping it street legal is what I'm looking at if that helps.
Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
You're semi-local to me! Same year too 
The first thing i would do is upgrade the exhaust. Gut the cat/ weld in a straight pipe, get some free flowing mufflers, and if you want to, you could upgrade the pipe size to 2.5" and run true duals. You could also install headers.
Next I would do the intake. Since its a street car I would keep it TPI and install big tube runners, a better base (or port your own base) and port your plenum. Or you could install the FIRST TPI. (http://firstfuelinjection.com/PDRM1966.JPG) this thing is massive, its so big you could probably stuff the stock TPI inside of it. If you want it to have more top end power you could do a miniram.
Since the cylinder heads in 85 sucked extremely, I would recommend getting better heads. A lot of people use AFR's on their cars and say that they perform very well.
A lot of it depends on your budget. how much do you have to spend?
The first thing i would do is upgrade the exhaust. Gut the cat/ weld in a straight pipe, get some free flowing mufflers, and if you want to, you could upgrade the pipe size to 2.5" and run true duals. You could also install headers.
Next I would do the intake. Since its a street car I would keep it TPI and install big tube runners, a better base (or port your own base) and port your plenum. Or you could install the FIRST TPI. (http://firstfuelinjection.com/PDRM1966.JPG) this thing is massive, its so big you could probably stuff the stock TPI inside of it. If you want it to have more top end power you could do a miniram.
Since the cylinder heads in 85 sucked extremely, I would recommend getting better heads. A lot of people use AFR's on their cars and say that they perform very well.
A lot of it depends on your budget. how much do you have to spend?
Last edited by Pwnage1337; Aug 12, 2009 at 12:34 PM.
Thread Starter
Intermediate
Joined: Jul 2007
Posts: 45
Likes: 0
From: Stevens Point WI
I'm not worried about budget at this point. It's one of those where I'd like to get the ideal build first and then determine whether or not I should take it down a notch or not.
BTW, I've got an ugly story about my experience with Amherst. Was going back to MN for Christmas one year, passed through Amherst, had a sheet of ice go through my windshield. Flew off the top of a semi. Not fun. Fortunately only the windshield was damaged and I walked away with a couple scratches.
BTW, I've got an ugly story about my experience with Amherst. Was going back to MN for Christmas one year, passed through Amherst, had a sheet of ice go through my windshield. Flew off the top of a semi. Not fun. Fortunately only the windshield was damaged and I walked away with a couple scratches.
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
If you want to do a real upgrade buy a ZZ4 type long block. That way you will upgrade your heads, cam, and go to a roller type motor all at once. You can also use your stock intake or upgrade that as well. Check the GMPP sellers for prices, ZZ4's are very common.
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Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
I'm not worried about budget at this point. It's one of those where I'd like to get the ideal build first and then determine whether or not I should take it down a notch or not.
BTW, I've got an ugly story about my experience with Amherst. Was going back to MN for Christmas one year, passed through Amherst, had a sheet of ice go through my windshield. Flew off the top of a semi. Not fun. Fortunately only the windshield was damaged and I walked away with a couple scratches.
BTW, I've got an ugly story about my experience with Amherst. Was going back to MN for Christmas one year, passed through Amherst, had a sheet of ice go through my windshield. Flew off the top of a semi. Not fun. Fortunately only the windshield was damaged and I walked away with a couple scratches.
You should put a blower on it from blowerworks.net.
That would be badass.
Tech Contributor
Joined: Oct 2008
Posts: 3,729
Likes: 190
From: Custer, WI
Like the FIRST. or the SuperRam. or the MiniRam. or a Holley Stealth Ram. or a LT1 style intake. or a Ported Plenum, Big mouth base and big tube runners.
Thread Starter
Intermediate
Joined: Jul 2007
Posts: 45
Likes: 0
From: Stevens Point WI
Thanks for the responses so far everyone. This helps out quite a bit. Keep em coming!
Race Director
Joined: Jun 1999
Posts: 14,924
Likes: 9
From: Merritt Ils Fl
Best solution and very likely the most cost effective.
Le Mans Master
Joined: Mar 2004
Posts: 5,107
Likes: 171
From: Dublin CA
You can buy the short block version of the ZZ4 from Summit. It comes with steel crank, bearings, connecting rods and pistons with rings...assembled like that. You have to add cam, heads, timing set and the rest. It is a good start. I pulled apart my short block and had it all balanced.....I would recommend this step.
I am still fine tuning my setup. It is a mild build. The car ran 13.2 in the quarter at 107+ MPH. I get 28.4 MPG on the highway and have a solid 21.7 MPG mixed town and highway. All on regular 87 fuel.
Check out VADER86's site.....lots of good information.
I am still fine tuning my setup. It is a mild build. The car ran 13.2 in the quarter at 107+ MPH. I get 28.4 MPG on the highway and have a solid 21.7 MPG mixed town and highway. All on regular 87 fuel.
Check out VADER86's site.....lots of good information.
Thread Starter
Intermediate
Joined: Jul 2007
Posts: 45
Likes: 0
From: Stevens Point WI
That will make things easier.
Now, what parts would you guys go with to bring the HP up. I'm thinking somewhere in the range of 400HP.
Is it better to piece it together part by part or to buy a kit that has the bulk of the parts picked out for you already?
Personally I want to put it all together myself versus having a pre-built one delivered.
The other question I have is how far, HP wise, can I go before I'd have to start upgrading the drivetrain?
Now, what parts would you guys go with to bring the HP up. I'm thinking somewhere in the range of 400HP.
Is it better to piece it together part by part or to buy a kit that has the bulk of the parts picked out for you already?
Personally I want to put it all together myself versus having a pre-built one delivered.
The other question I have is how far, HP wise, can I go before I'd have to start upgrading the drivetrain?
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
Stock intake on a motor with heads/cam would be a really bad idea. You would definitely want to get an intake that can flow close to the flow of the heads.
Like the FIRST. or the SuperRam. or the MiniRam. or a Holley Stealth Ram. or a LT1 style intake. or a Ported Plenum, Big mouth base and big tube runners.
Like the FIRST. or the SuperRam. or the MiniRam. or a Holley Stealth Ram. or a LT1 style intake. or a Ported Plenum, Big mouth base and big tube runners.
Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
That will make things easier.
Now, what parts would you guys go with to bring the HP up. I'm thinking somewhere in the range of 400HP.
Is it better to piece it together part by part or to buy a kit that has the bulk of the parts picked out for you already?
Personally I want to put it all together myself versus having a pre-built one delivered.
The other question I have is how far, HP wise, can I go before I'd have to start upgrading the drivetrain?
Now, what parts would you guys go with to bring the HP up. I'm thinking somewhere in the range of 400HP.
Is it better to piece it together part by part or to buy a kit that has the bulk of the parts picked out for you already?
Personally I want to put it all together myself versus having a pre-built one delivered.
The other question I have is how far, HP wise, can I go before I'd have to start upgrading the drivetrain?
