1981 Corvette with a 350 vortec engine?
Thread Starter
Cruising
Joined: Aug 2011
Posts: 11
Likes: 0
From: DFW TX
1981 Corvette with a 350 vortec engine?
Hey Guys,
Im trying to help a customer out. He has a 1981 corvette that he says originally had a 350ci engine in it. He purchased our 350 vortec engine complete carb to pan with a low rise intake, stock 4qt oil pan, 1981 year correct water pump.
Is their any reason the Oil Pan will not fit? Also they are telling him the FAN SHROUD will not work/fit now....and he needs to go to an electric fan setup....the customer swapped over to the newer serpentine setup as well (just an FYI)...thinking now maybe it had the Long Water pump in that kit thats effecting the shroud....rather than the short water pump..They also changed motor mounts...now im wondering if they got the wrong ones or moved them up somehow/installed them wrong.....???
Can you give me some insight...? We sell 100+ of this particular engine package a year and have NEVER heard of these problems....
This is a picture of the typical package so you can see what we are working with....
Im trying to help a customer out. He has a 1981 corvette that he says originally had a 350ci engine in it. He purchased our 350 vortec engine complete carb to pan with a low rise intake, stock 4qt oil pan, 1981 year correct water pump.
Is their any reason the Oil Pan will not fit? Also they are telling him the FAN SHROUD will not work/fit now....and he needs to go to an electric fan setup....the customer swapped over to the newer serpentine setup as well (just an FYI)...thinking now maybe it had the Long Water pump in that kit thats effecting the shroud....rather than the short water pump..They also changed motor mounts...now im wondering if they got the wrong ones or moved them up somehow/installed them wrong.....???
Can you give me some insight...? We sell 100+ of this particular engine package a year and have NEVER heard of these problems....
This is a picture of the typical package so you can see what we are working with....
Last edited by Notalent; Mar 1, 2012 at 01:06 PM.
Pro
Joined: Feb 2012
Posts: 577
Likes: 6
The oil pan clearance is tight no matter what. Less than .5" in some cases. Is it actually hitting or preventing installation or just closer than they are comfortable with? Also if they went with a GM serpentine setup they had to install a long reverse flow water pump and that indeed means that the mechanical fan will not work. They are correct stating an upgrade to an electric fan setup is needed.
Thread Starter
Cruising
Joined: Aug 2011
Posts: 11
Likes: 0
From: DFW TX
Thanks for your insight Mark.
I spoke to my rep @ Scoggin Dickey and that Serpentine Kit will infact work with a Short Water Pump, im guessing they did not read the instructions and use the short water pump needed which is throwing things off....The rep has an 80 & 81 vette himself...
In regards to the oil pan....is it a different design? I have searched everywhere high and low and offered to buy the customer a new pan if it will fit....we cant find a difference....which leads me to believe the motor mounts were messed up somehow or they may have installed the wrong ones....and its causing it to hit a steering component...
I spoke to my rep @ Scoggin Dickey and that Serpentine Kit will infact work with a Short Water Pump, im guessing they did not read the instructions and use the short water pump needed which is throwing things off....The rep has an 80 & 81 vette himself...
In regards to the oil pan....is it a different design? I have searched everywhere high and low and offered to buy the customer a new pan if it will fit....we cant find a difference....which leads me to believe the motor mounts were messed up somehow or they may have installed the wrong ones....and its causing it to hit a steering component...
Pro
Joined: Feb 2012
Posts: 577
Likes: 6
Thanks for your insight Mark.
I spoke to my rep @ Scoggin Dickey and that Serpentine Kit will infact work with a Short Water Pump, im guessing they did not read the instructions and use the short water pump needed which is throwing things off....The rep has an 80 & 81 vette himself...
In regards to the oil pan....is it a different design? I have searched everywhere high and low and offered to buy the customer a new pan if it will fit....we cant find a difference....which leads me to believe the motor mounts were messed up somehow or they may have installed the wrong ones....and its causing it to hit a steering component...
I spoke to my rep @ Scoggin Dickey and that Serpentine Kit will infact work with a Short Water Pump, im guessing they did not read the instructions and use the short water pump needed which is throwing things off....The rep has an 80 & 81 vette himself...
In regards to the oil pan....is it a different design? I have searched everywhere high and low and offered to buy the customer a new pan if it will fit....we cant find a difference....which leads me to believe the motor mounts were messed up somehow or they may have installed the wrong ones....and its causing it to hit a steering component...
The pan design is different between the one piece and two piece rear main seals but there are a lot of guys with GM crate engines of this design and you have to use the pan for the rear main. That pan should fit in the C3. As you mentioned something else may be the cause. Motor mounts are hard to get wrong. Maybe ask for the part number of the mounts they bought and investigate for yourself to make sure they are Corvette specific. Goes without saying that they can't just use any old set off the shelf.
Thread Starter
Cruising
Joined: Aug 2011
Posts: 11
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From: DFW TX
I called the Chevy Dealership (Martin Chevrolet in LA)where its being installed and asked for a Motor mount part # and never got it....these guys just dont want to work with me to help the customer....the service manager blatantly said he was hesitant to work with the customer because he didnt buy an engine from them....and that he had a chance too....that is very sad to hear that...
On these years....do you have to loosen or remove the crossmember to get the engine in?
On these years....do you have to loosen or remove the crossmember to get the engine in?
Pro
Joined: Feb 2012
Posts: 577
Likes: 6
I called the Chevy Dealership (Martin Chevrolet in LA)where its being installed and asked for a Motor mount part # and never got it....these guys just dont want to work with me to help the customer....the service manager blatantly said he was hesitant to work with the customer because he didnt buy an engine from them....and that he had a chance too....that is very sad to hear that...
On these years....do you have to loosen or remove the crossmember to get the engine in?
On these years....do you have to loosen or remove the crossmember to get the engine in?
No the front cross member just forward is not removable or adjustable, nor are the horns the engine mounts sit on. The engine mounts slide right over and rest so you can't even go to low if the mounts are installed properly. They are not side specific either so left and right engine mounts are the same.
Drifting
Joined: Dec 2002
Posts: 1,946
Likes: 28
From: Long Beach CA
Martin Chevrolet in the LA area? Well, that explains a lot. That's about the last place I'd go to just to buy parts over the counter, let alone have them do work on my car.
FYI, they at one time sponsored a local Corvette club, but kicked them out so the club had to go searching for another sponsor.
FYI, they at one time sponsored a local Corvette club, but kicked them out so the club had to go searching for another sponsor.
Thread Starter
Cruising
Joined: Aug 2011
Posts: 11
Likes: 0
From: DFW TX
Martin Chevrolet in the LA area? Well, that explains a lot. That's about the last place I'd go to just to buy parts over the counter, let alone have them do work on my car.
FYI, they at one time sponsored a local Corvette club, but kicked them out so the club had to go searching for another sponsor.
FYI, they at one time sponsored a local Corvette club, but kicked them out so the club had to go searching for another sponsor.
Not Los Angeles, but Breaux Bridge,Louisiana..
Hpoefully not the same place....
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Drifting
Joined: Sep 2006
Posts: 1,986
Likes: 21
From: Columbus MN
If that engine is the GM 350 HO (330 hp), then that is the engine I have in my '80. It went in without any fit problems down below with the GM oil pan and standard SBC motor mounts. (I have poly mounts in now.)
The fan shroud will work with the HO, but the stock air cleaner and intake snorkles will not, I started with a 14" drop base, a 14x3 air cleaner (K&N), and a slightly domed air cleaner lid with a 1/4" flat head stainless steel machine screw in place of the normal air clear lid stud and wing nut. The wing nut and stud pressed HARD against the underside of the hood. I then removed the fan shroud, switched to dual electric fans-only, and made a custom cold air intake.
To get the most out of that engine, you will need to modify the carb and distributor, especially with a true dual exhaust. Once tweaked, that engine will exceed it's advertixed hp and torque. Here is the info I posted:
GM 350 HO dyno results
That engine will top 400 hp with the GM LT1 Hot Cam Kit (that includes 1.6 rollers) and Comp Cam springs.
The fan shroud will work with the HO, but the stock air cleaner and intake snorkles will not, I started with a 14" drop base, a 14x3 air cleaner (K&N), and a slightly domed air cleaner lid with a 1/4" flat head stainless steel machine screw in place of the normal air clear lid stud and wing nut. The wing nut and stud pressed HARD against the underside of the hood. I then removed the fan shroud, switched to dual electric fans-only, and made a custom cold air intake.
To get the most out of that engine, you will need to modify the carb and distributor, especially with a true dual exhaust. Once tweaked, that engine will exceed it's advertixed hp and torque. Here is the info I posted:
GM 350 HO dyno results
That engine will top 400 hp with the GM LT1 Hot Cam Kit (that includes 1.6 rollers) and Comp Cam springs.
