Advice on using 383 replacement engine
Thread Starter
Instructor
Joined: Dec 2006
Posts: 198
Likes: 30
From: Denver CO
Advice on using 383 replacement engine
I'm considering bagging my #'s 327/300 and replacing with a 383 stroker. The 383 has 10.25: compression and a 490 lift cam. Will I be ok using my stock radiator (radiator works fine right now) or am I going to need to change it to avoid heat problems?
Also, the engine builder recommends using a non-vacuum advance distributor for the motor. Says it is easier to tune, runs better etc., but is about $600 for the CDI, coil & distributor. Is this set up really necessary vs. an HEI or other? Is this a serious issue for engine performance? Will an HEI ignition even fit or is it too tight for the firewall?
Thanks very much in advance...
Also, the engine builder recommends using a non-vacuum advance distributor for the motor. Says it is easier to tune, runs better etc., but is about $600 for the CDI, coil & distributor. Is this set up really necessary vs. an HEI or other? Is this a serious issue for engine performance? Will an HEI ignition even fit or is it too tight for the firewall?
Thanks very much in advance...
Team Owner
Joined: Oct 2000
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From: Washington Michigan
http://www.lbfun.com/warehouse/tech_...101Article.pdf
Thread Starter
Instructor
Joined: Dec 2006
Posts: 198
Likes: 30
From: Denver CO
383 and potential heat problems?
Several forum members have installed 383's in their cars. Is anyone out there experiencing any overheating problems with their stock small block radiator and clutch fan set up? Just wondering if I need to change any of my current cooling system if I run a 383 engine- thanks
Pro
Joined: Sep 2008
Posts: 682
Likes: 0
From: Manteo NC
I have a 355 built to supposedly 400Hp with a stock rad and direct drive 7 blade stainless fan. It runs all day at 165 in 65 degreee temp. I guess I better go buy me a vacuum advance as my MSD is mechanical. I hate learning this stuff the expensive way but I should a known.
Never ceases to amaze me the variations of advice you will get when asking 'good mechanics'.
Never ceases to amaze me the variations of advice you will get when asking 'good mechanics'.
Team Owner
Joined: Mar 2003
Posts: 26,118
Likes: 1,874
From: Greenville, Indiana
I have a 355 built to supposedly 400Hp with a stock rad and direct drive 7 blade stainless fan. It runs all day at 165 in 65 degreee temp. I guess I better go buy me a vacuum advance as my MSD is mechanical. I hate learning this stuff the expensive way but I should a known.
Never ceases to amaze me the variations of advice you will get when asking 'good mechanics'.
Never ceases to amaze me the variations of advice you will get when asking 'good mechanics'.
I think it's safe to say the mechanical distributor would be best for mostly competition use and the vacuum advance unit would be best for mostly street driving. Either will work either way but not ideally.
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Burning Brakes
Joined: Jan 2007
Posts: 1,104
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From: Woonsocket Rhode Island
I do not have a 383 but did install an original 1970 LT-1 crate engine with my original radiator which is OLD. On any day where temps went over 65 deg I ran really hot but not enough to boil over the fluid. I did that for about 4 years until I finially added a high density 4 core and now the temp runs a lot cooler in any temp.
You might try to keep the original but a new one might be less worry.
You might try to keep the original but a new one might be less worry.
Race Director
Joined: Mar 2001
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From: Mustang OK
2026 Corvette of the Year Finalist - Modified
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Why do people no longer build their own custom engines?
Building a 383 from a rebuildable 350 block and a good used 400 crank (or just buying a 3.75 stroke crank) is just too easy. Plus, when you're done, you have the satisfaction of doing it yourself as well as KNOWING what's inside.
Engine building IS NOT rocket science!
Building a 383 from a rebuildable 350 block and a good used 400 crank (or just buying a 3.75 stroke crank) is just too easy. Plus, when you're done, you have the satisfaction of doing it yourself as well as KNOWING what's inside.
Engine building IS NOT rocket science!
CF Community Team
Joined: Oct 2004
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From: Cape Cod, Mass.
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Several forum members have installed 383's in their cars. Is anyone out there experiencing any overheating problems with their stock small block radiator and clutch fan set up? Just wondering if I need to change any of my current cooling system if I run a 383 engine- thanks
Team Owner
Joined: Nov 2005
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From: Beach & High Desert Southern California
Also, the engine builder recommends using a non-vacuum advance distributor for the motor. Says it is easier to tune, runs better etc., but is about $600 for the CDI, coil & distributor. Is this set up really necessary vs. an HEI or other? Is this a serious issue for engine performance? Will an HEI ignition even fit or is it too tight for the firewall?
Thanks very much in advance...
Thanks very much in advance...
The non-vacuum advance distributor is easier to set-up & tune (it ignores tuning the vacuum advance), but it does not run better.
The engine with the non-vacuum distributor will run the same at Wide Open Throttle (WOT). This is because at WOT the vacuum advance is not employed (there is minimal vacuum, and no impact from the vacuum advance). Racers drive everywhere at WOT, but most of the rest of us take our foot out of the throttle now & then.
The engine with the non-vacuum distributor will NOT run the same at partial throttle, at the throttle positions most of us drive every day. It will get lower fuel mileage and have a less powerful response to slight throttle inputs (and can motivate the engine to overheat). This is because at partial throttle, vacuum advance is employed to provide better power and fuel economy. Vacuum advance is a benefit when the engine can use a little timing advance efficiency boost without detonation.
The HEI will fit the engine compartment, but not the original ignition shielding, and it will not fit many of the original air cleaner housings and intake manifolds. A good standard cap distributor will work just as well (with a quality points replacement electronic trigger if you want the same reduced tune-up advantage of the HEI).
Instructor
Joined: Sep 2002
Posts: 227
Likes: 0
From: Barnstable Mass
I have a 383 dyno'd @ 455HP that runs @ 180 summer and winter. Like Capevettes, I put in a new Dewitt's radiator (the least expensive one!) and I run a 7 blade Flexalite fan. I use a vacuum advance HEI with tach drive from Summit.
Drifting
Joined: Sep 2004
Posts: 1,665
Likes: 60
From: Buffalo New York
I have the GM zz383 stroker in my '66. I am running a Dewitts replacement aluminum radiator with a MSD vacum advance distributor. I have a stock fan clutch and fan. My radiator shroud fits correctly and the fan sits in the shroud correctly. My car runs 180* all the time. Hot day, cool day, highway and local streets. I would urge you not to use the mechanical distributor and go with a vacum advance model. It is absolutely essential for a cool running engine in a C2.
Dennis
Dennis
Last edited by Dennis Beck; Mar 9, 2009 at 09:44 PM.
Melting Slicks
Joined: Aug 2004
Posts: 2,241
Likes: 6
From: Arizona
Why do people no longer build their own custom engines?
Building a 383 from a rebuildable 350 block and a good used 400 crank (or just buying a 3.75 stroke crank) is just too easy. Plus, when you're done, you have the satisfaction of doing it yourself as well as KNOWING what's inside.
Engine building IS NOT rocket science!
Building a 383 from a rebuildable 350 block and a good used 400 crank (or just buying a 3.75 stroke crank) is just too easy. Plus, when you're done, you have the satisfaction of doing it yourself as well as KNOWING what's inside.
Engine building IS NOT rocket science!
Racer
Joined: Feb 2005
Posts: 329
Likes: 18
Why do people no longer build their own custom engines?
Building a 383 from a rebuildable 350 block and a good used 400 crank (or just buying a 3.75 stroke crank) is just too easy. Plus, when you're done, you have the satisfaction of doing it yourself as well as KNOWING what's inside.
Engine building IS NOT rocket science!
Building a 383 from a rebuildable 350 block and a good used 400 crank (or just buying a 3.75 stroke crank) is just too easy. Plus, when you're done, you have the satisfaction of doing it yourself as well as KNOWING what's inside.
Engine building IS NOT rocket science!
Well said ! I guess it's just a different generation. You don't have to know anything but how to write a check today.
Drifting
Joined: Nov 2007
Posts: 1,513
Likes: 34
From: columbus ohio
i am no mechanic. i would love to build my own engine. but i have no
clue for clearances on bearings, clearances on the heads (which gasket
to use) and such. i would have to have a good mechanic sit and watch
me. if i pay a guy to do that then a crate engine would be cheaper. i am
not afraid to try things, but a engine is too expense for me to possible
screw up. i never had the training for this, which i really wish i had. i
am thinking of going back to school just to learn. but i have to wait till
the stock market rebounds a little. jim
clue for clearances on bearings, clearances on the heads (which gasket
to use) and such. i would have to have a good mechanic sit and watch
me. if i pay a guy to do that then a crate engine would be cheaper. i am
not afraid to try things, but a engine is too expense for me to possible
screw up. i never had the training for this, which i really wish i had. i
am thinking of going back to school just to learn. but i have to wait till
the stock market rebounds a little. jim
Race Director
Joined: Mar 2001
Posts: 14,632
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From: Mustang OK
2026 Corvette of the Year Finalist - Modified
2025 c1 of the Year - Modified Winner
2024 C1 of the Year Finalist - Modified
2023 C1 of the Year Finalist - Modified
2015 C1 of the Year Finalist
i am no mechanic. i would love to build my own engine. but i have no
clue for clearances on bearings, clearances on the heads (which gasket
to use) and such. i would have to have a good mechanic sit and watch
me. if i pay a guy to do that then a crate engine would be cheaper. i am
not afraid to try things, but a engine is too expense for me to possible
screw up. i never had the training for this, which i really wish i had. i
am thinking of going back to school just to learn. but i have to wait till
the stock market rebounds a little. jim
clue for clearances on bearings, clearances on the heads (which gasket
to use) and such. i would have to have a good mechanic sit and watch
me. if i pay a guy to do that then a crate engine would be cheaper. i am
not afraid to try things, but a engine is too expense for me to possible
screw up. i never had the training for this, which i really wish i had. i
am thinking of going back to school just to learn. but i have to wait till
the stock market rebounds a little. jim
If for example, a guy brings me a Muncie for a rebuilt/repair and says he'll pick it up next week, then he gets charged a full bore price for a rebuild plus parts.
But if someone comes over with his Muncie and asks me to help him to rebuild it, there is no charge (of course, he buys parts). Does no one do this any more????
Team Owner
Joined: Aug 2007
Posts: 58,061
Likes: 7,146
Army
Is there no longer such a thing as a "buddy" that will come over and help/guide with these kinds of efforts?
If for example, a guy brings me a Muncie for a rebuilt/repair and says he'll pick it up next week, then he gets charged a full bore price for a rebuild plus parts.
But if someone comes over with his Muncie and asks me to help him to rebuild it, there is no charge (of course, he buys parts). Does no one do this any more????
If for example, a guy brings me a Muncie for a rebuilt/repair and says he'll pick it up next week, then he gets charged a full bore price for a rebuild plus parts.
But if someone comes over with his Muncie and asks me to help him to rebuild it, there is no charge (of course, he buys parts). Does no one do this any more????
As to 'rolling your own' on a custom engine..I just hear too many stories from novices where the combination of 'hot' parts they bolt together either doesn't live up to their expectations or is a complete disaster. Its also nice to have that crate motor warranty.
Drifting
Joined: Nov 2007
Posts: 1,513
Likes: 34
From: columbus ohio
dzauto, i wish i had a buddy. i had to retire early and take care of my wife. it is my fault that i shut off my old police friends, but i was busy.
i have not known a mechanic untill now. but steve is slowing down and
just does small jobs at his house. he will build me a engine, but he recommends a crate engine. he has done me good on my nailhead and vette. i just started to get into cars again after my wife died in 2007. it took a while for me to get moving around again. so yes i have friends,
but police officers i know do not build engines. when i decide to replace
the orig in the vette i will go to steve. we will decide on which one to get and i will be helping him pull the old and put in the new. just like when i put a 400 tranny in place of the 300 that was in the nail. boy that was a trip trying to find a nailhead 400 tranny. steve is old school, hell he doesn't even have a dvd player in his house. i know i am one of the few on this board that is not a mechanic or plays one. now if you need plumbing, tiling, or room addition i can jump right in. no electrical i fall on my *** every time, because i am to lazy to turn the breakers off. jim
i have not known a mechanic untill now. but steve is slowing down and
just does small jobs at his house. he will build me a engine, but he recommends a crate engine. he has done me good on my nailhead and vette. i just started to get into cars again after my wife died in 2007. it took a while for me to get moving around again. so yes i have friends,
but police officers i know do not build engines. when i decide to replace
the orig in the vette i will go to steve. we will decide on which one to get and i will be helping him pull the old and put in the new. just like when i put a 400 tranny in place of the 300 that was in the nail. boy that was a trip trying to find a nailhead 400 tranny. steve is old school, hell he doesn't even have a dvd player in his house. i know i am one of the few on this board that is not a mechanic or plays one. now if you need plumbing, tiling, or room addition i can jump right in. no electrical i fall on my *** every time, because i am to lazy to turn the breakers off. jim