383 or 400
Team Owner
Joined: Sep 2001
Posts: 62,140
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From: Athens AL
C7 of the Year - Unmodified Finalist 2021
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Re: 383 or 400 (cyclerage23)
bigger is better
just depends on what you need out of it and how much money you have to spend
just depends on what you need out of it and how much money you have to spend
Racer
Joined: Jul 2003
Posts: 261
Likes: 0
From: Millington Tennessee
St. Jude Contributor
Re: 383 or 400 (cyclerage23)
If you can find a good 400 block for reasonable money go that route because the crank/rods/pistons are the same $$$ as a 383. The only real $$$ difference between a 383 and a 400 is the 400 block and buying retrofit roller lifters if you go that route. The benefits of the 383 are the ease of finding a good block and you can get a block that is already setup for a roller cam.
Burning Brakes
Joined: May 2003
Posts: 822
Likes: 0
From: Beverly, MA MA
Re: 383 or 400 (cyclerage23)
The 400 block is one tough mother it has sieamised cylinders, but this caused a cooling problem.(lots of cracked heads and blown gaskets) If you do go with it you will need to drill steam holes in the heads unless you use the stock heads (why would you do that?) second they only make a cast crank (oem) for the 400, it's a tq. monster no dought but I would build a 383 if I had a choice. As far as the roller cam and lifters go the price for oem. or retro is about the same give or take $20.00! :flag
[Modified by offershore, 9:18 PM 8/12/2003]
[Modified by offershore, 9:18 PM 8/12/2003]
Melting Slicks
Joined: Sep 2000
Posts: 3,099
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From: PITTSBURGH PA
Cruise-In IV Veteran
Cruise-In V Veteran
Re: 383 or 400 (offershore)
406 is the way if you want to make more power everything being equal about 25-30 hp more
offshore which crank do you think they use in a std 383 build can you say 400 cut down :cool: :cheers:
ps and you do not need steam holes and i've yet to see a 400 that was built up crack cylinder heads i know because i have built a couple dozen 400 motors :cheers:
[Modified by CORKVETTE1, 4:54 PM 8/12/2003]
offshore which crank do you think they use in a std 383 build can you say 400 cut down :cool: :cheers:
ps and you do not need steam holes and i've yet to see a 400 that was built up crack cylinder heads i know because i have built a couple dozen 400 motors :cheers:
[Modified by CORKVETTE1, 4:54 PM 8/12/2003]
Burning Brakes
Joined: Oct 2002
Posts: 1,193
Likes: 1
From: Meadville PA
Re: 383 or 400 (cyclerage23)
in my opinion you can find plenty of 400 blocks at your local marina being used as boat anchors :lolg: i would go with a 383 if you want reliablity and a very respectable motor....400's are junk with thier thin cylinder walls and constant over heating problems they are just not a reliable street motor... botom line is a 400 block is to weak... alot of the racers around hear have abondoned the 406's and went 383 and are running better with them and running longer.. just my 2 cents :cheers:
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Racer
Joined: Jul 2003
Posts: 261
Likes: 0
From: Millington Tennessee
St. Jude Contributor
Re: 383 or 400 (offershore)
If you do go with it you will need to drill steam holes in the heads unless you use the stock heads (why would you do that?) second they only make a cast crank (oem) for the 400, it's a tq. monster no dought but I would build a 383 if I had a choice. As far as the roller cam and lifters go the price for oem. or retro is about the same give or take $20.00! :flag
[Modified by offershore, 9:18 PM 8/12/2003]
[Modified by offershore, 9:18 PM 8/12/2003]
[Modified by thepenguin99, 4:08 PM 8/12/2003]
Thread Starter
Melting Slicks
Joined: Aug 2002
Posts: 3,333
Likes: 1
From: Central NJ/PA
Re: 383 or 400 (1989redvette)
What has to get clearanced, just around the pan rails right?
I have a 383 crower steel crank already so thats not an issue. It is cut to fit the 350 journels. If I go with the 400 block I can use those spacer bearing but are they any good? Are 400 blocks that prevalent to failer?This will be a street car. I already have the retrofit hydro lifters as well.
I have a 383 crower steel crank already so thats not an issue. It is cut to fit the 350 journels. If I go with the 400 block I can use those spacer bearing but are they any good? Are 400 blocks that prevalent to failer?This will be a street car. I already have the retrofit hydro lifters as well.
Burning Brakes
Joined: Dec 2002
Posts: 947
Likes: 0
From: Middletown N.Y.
Re: 383 or 400 (cyclerage23)
I have a fully machined 400 block for sale, also a 1-piece rear seal 350 roller block. The 400 is a original 4-bolt block it's been sonic tested and bored over .040", honed, align honed with ARP main stud kit , cam bearings , freeze plugs and decked .010. Before we went .040" we made sure the cylinders had enough thickness otherwise we would have junked the block, usually 4 bolt blocks are less desireable but for a 400-550hp build up this block is great this particular block still has .200" around the cylinders, my machinist said it's the thickest 400 block he's seen yet! . I have no use for it . It was machined about a month ago . I spent around $700 to get it done . I'll entertain offers. The 350 block is not machined has original bore $100.
[Modified by JUAN J SANCHEZ, 12:05 AM 8/13/2003]
[Modified by JUAN J SANCHEZ, 12:05 AM 8/13/2003]
Melting Slicks
Joined: Sep 2000
Posts: 2,710
Likes: 1
From: Green Bay WI
Re: 383 or 400 (cyclerage23)
I'm going to build another engine but I wanted to hear a few different opinions on whats better power. Thanks,Jason
Drifting
Joined: Feb 2002
Posts: 1,952
Likes: 2
From: Little Rock Arkansas
Re: 383 or 400 (cprgmr)
As an engine builder I'll give you my opinion... 6 of one/half dozen of the other... It really depends on what you want out of the engine; either is as reliable as the quality of the components and the care of machine work/assembly. 4-bolt 400 blocks are weaker than 2-bolt 400 blocks in the main webbing because of thinner material in that area as a result of the larger bore. Properly built 400 do NOT suffer from cooling problems, nor are they "weak." The larger bore of the 400 unshrouds the combustion chambers in the heads and allows them to breathe better; as a result they tend to make more horsepower than smaller bores (like the 4.030" bore found in the 383). In combination with the long 3.75" stroke the 400 gets the nod for the higher power producer (both torque and hp). 400 blocks ARE getting scarce and harder to find though 350 blocks are a dime a dozen...
-Jeb
PS- Forgot...I do have a new 4340 forged, cryo-treated, nitrided 3.75" 400 main crank if anyone's interested...
[Modified by jburnett, 3:29 AM 8/13/2003]
-Jeb
PS- Forgot...I do have a new 4340 forged, cryo-treated, nitrided 3.75" 400 main crank if anyone's interested...
[Modified by jburnett, 3:29 AM 8/13/2003]
Drifting
Joined: Feb 2002
Posts: 1,952
Likes: 2
From: Little Rock Arkansas
Re: 383 or 400 (offershore)
Well...I haven't had any problems in the ones I've done (which are many considering I'm in the south and build a ton of 400 based motors for dirt trackers); they are subject to air pockets because of their siamesed bores...However, that is as much proper bleeding of the cooling system as anything else. That being said: Your Mileage May Vary...
Juan, I need to get $585.00 out of it...
-Jeb
[Modified by jburnett, 3:57 AM 8/13/2003]
Juan, I need to get $585.00 out of it...
-Jeb
[Modified by jburnett, 3:57 AM 8/13/2003]
Melting Slicks
Joined: Sep 2000
Posts: 3,099
Likes: 0
From: PITTSBURGH PA
Cruise-In IV Veteran
Cruise-In V Veteran
Re: 383 or 400 (thepenguin99)
If you do go with it you will need to drill steam holes in the heads unless you use the stock heads (why would you do that?) second they only make a cast crank (oem) for the 400, it's a tq. monster no dought but I would build a 383 if I had a choice. As far as the roller cam and lifters go the price for oem. or retro is about the same give or take $20.00! :flag
[Modified by offershore, 9:18 PM 8/12/2003]
I dont see why oem cast 400 cranks are a factor. Unless you are going for a blower, turbo, and big nos the $200ish scat 9000 series crank will work fine for both the 383 and 400. If you are going for some super HP, many companies offer forged cranks for the 400 as well as 383. The 383 has no benefit over the 400 other than costs of finding the block and slightly more expensive roller lifters if comparing to aftermarket (a lot more expensive compared to stock roller lifters you could use in a 383). The machining costs for having the heads drilled would probably be less than clearancing the 350 block. On another note both the clearancing and the steam holes are things you could do yourself (not recommended if you have no idea what you are doing).
[Modified by thepenguin99, 4:08 PM 8/12/2003]
[Modified by offershore, 9:18 PM 8/12/2003]
I dont see why oem cast 400 cranks are a factor. Unless you are going for a blower, turbo, and big nos the $200ish scat 9000 series crank will work fine for both the 383 and 400. If you are going for some super HP, many companies offer forged cranks for the 400 as well as 383. The 383 has no benefit over the 400 other than costs of finding the block and slightly more expensive roller lifters if comparing to aftermarket (a lot more expensive compared to stock roller lifters you could use in a 383). The machining costs for having the heads drilled would probably be less than clearancing the 350 block. On another note both the clearancing and the steam holes are things you could do yourself (not recommended if you have no idea what you are doing).
[Modified by thepenguin99, 4:08 PM 8/12/2003]
THEPENGUIN99 I AM NOT TRYING TO BUST YOUR CHOPS BUT THE 383 AND 400S USE THE EXACT SAME LIFTERS
:cheers: