Chevy 400 vs 350. Uncover their specs, performance, reliability, and impact on iconic muscle cars. but, whats the difference in the 350 and 400 block castings? and, how far can you go with the 350 2blt block as far as safe boring/stroke with crank kits ? I ask because I wanted to build a 406 BUT I am having a hard time Feb 27, 2009 · Engine Mods - Internal Differences between 350 and 400? - I got a 400ci block and I have been talking to my machinist about what I am going to have done. May 14, 2023 · In this article, we will explore the key differences between the Chevy 350 and 400 small block engines, including their displacement, design, and performance characteristics. Oct 8, 2009 · Well I have been through 4 different engines in two different trucks and I have experience with 3 different 350 sbc's and one 350 stroked to 383 with the 400 small block crank. The 350 has a consistent outer edge. 487” register hole. 567 lift and this setup will rip your head off. Oct 26, 2004 · i have a 74 lemans with a pon 350 in it , i found a 400 pon bb. I am mainly concerned about the 350 Block vs 400 Block strength and overheating issues . I run 195 heads Apr 26, 2012 · A small block Chevy could be from 262-400" from the factory, and I'm guessing you wouldn't know what it was unless someone told you. This very first overhead Jun 8, 2024 · The Turbo 350 and Turbo 400 are two types of automatic transmissions commonly used in performance vehicles. . May 20, 2007 · Rear Axle to be either 12-Bolt Chevy or 9" Ford, Hydraulic Roller Camshaft & Gears will be selected, based on Combination Requirements. The 400 may be more expensive to build, but might cost less in the long run if you have to change trannies, etc. Is this right? If so can I just replace my 400 rods or do I need machine work? Feb 21, 2009 · Small Block 350 vs 400I'd get a 400 personally, bigger is better in the same size package, but if you broke a crank, whichever engine you get you need a forged crank and rods instead of the stock cast crank. The car seems to have the chevy 350 flywheel which is bad b/c the 400 is externally balanced and the flywheel is different. SAME turbo 400 trans and torque converter behind the 11-1?, big cam, low vacuum (Around 10 at idle) 350 sb with Holly double pumper acts entirely different! When the decision lies between two big and popular brands; TH350 vs TH400 transmission, you’ll need more than your intuition to guide you. Chevy crankshaft journal sizes for V8 Small Block, W 348-409, and Big Block engines> <meta name='Keywords Oct 10, 2021 · If you want to rebuild or swap your Turbo 350 or Turbo 400, you have to identify it to know what you're dealing with. 3 LS engine is the most popular iteration on the LS side of things. 7 rods. This is probably the best cylinder head casting that Chevrolet has ever produced for a production small block Chevy. Nov 26, 2014 · 400 mains are stronger, 350 mains have less friction. Mar 15, 2012 · C3 Tech/Performance - 383 vs 400 sbc - I built a 383 with hydraulic lifters, flat tappet cam, and vortec heads last fall. Although the crank installation is total simplicity, installing the rods and pistons can bring about a number of minor problems. So I am just curious. How did we do it, read the full article for details and some great tips. 125 inches vs. Depending on the heads, you might run out of breath at a lower RPM, though. We’ll help you determine the correct flexplate for your Chevy engine in this buyer’s guide. With modification, the TH-350 could be used as a high-torque transmission in a light car. The Turbo 400 three-speed automatic was launched in 1964 for Buicks and Cadillacs. 75" stroke, but the 350 has tiny 3. If you can find a 400 main sized crank that you like I would go that route for the added strength. From what I understand, the bore is larger on a 400, and you can put 400ci cranks in a 350 to get a Jun 5, 2006 · My 350 ci engine has a very back click inside. So comparing the turbo 350 vs. They differ in terms of their design and capabilities. 350 main sized cranks are easier/cheaper to find. Also, the 400’s intake manifold is wider, and the cylinder bores are larger (4. carcraft. A small block 350 and a 400 have an identical block design. Can the 400 fit into my 1968 SS Camaro? 2. Aug 28, 2001 · The differences between the Chevy and Pontiac 400 are as vast as the differences between a Chevy 350 and a Dodge 340. 75 inch stroke with 5. I used a 350 crank and 5. Aug 20, 2021 · Can someone tell me the difference in OVERALL length between the Short TH350 and the Short TH400 transmissions? I need the distance from the front surface that butts up against the engine block to the end of the tail shaft housing. Aug 25, 2022 · Are you confused about 400 small block vs 350 due to their similar block design? Let's check out this post for a detailed comparison of these two engines. There's also hugely more 350 cores to select from than 400 cores. 2285 6-7"=327 engine mount. Sep 26, 2003 · supposedly the 350 crank with the 400 block is a good engine for high RPM use. Referred to as a "small-block" for its size relative to the physically much larger Chevrolet big-block The turbo 350 transmission is short and light, making it utilize less power to spin. right now I have a 350 in my nova but my dad has a 400 in his 64 chevy truck and he is selling the truck. Small Block video. 00 cyl hole or larger for bore job. d. 030" overbore for a bore of 4. ? Engine & Drivetrain Dec 3, 2013 · What are the pros and cons of Turbo 350 and Turbo 400? I have a turbo 350 but I can get a turbo 400 locally for 200 dollars, too. 45". May 12, 2008 · 350 vs 400 interchangeable parts Pontiac - StreetPY Online Forums - Bringing the Pontiac Hobby Together > General Classic PONTIAC TECH > Pontiac - Street > 350 vs 400 interchangeable parts The most complete Chevrolet Big Block vs. The increased bore diameter required GM to alter the block internally with cylinder bores that did not allow for cooling passages between them. The 400 has a scalloped edge. It featured a 27 spline driveshaft with each pan in transmission able to take up to 4 quarts of oil. 3 LS vs 350 SBC comparison is going to be the given here, so let’s get into it! The Small Block Chevy 400 has an engine displacement of 400 cu. The 350 is internally balanced. The Chevy 350 and Chevy 400 are both popular V8 engines produced by Chevrolet. My build has a 0. The difference is about 50 cubic inches. ps can a 400 out run a chevy 350. HOW MUCH POWER DID A PONTIAC RAM AIR 400 MAKE? HOW MUCH POWER DID THE 1970 LT-1 350 REALLY MAKE? IS A RAM AIR 400 PONTIAC MORE POWERFUL THAN A CHEVY 350? IS THERE A REPLACEMENT FOR DISPLACEMENT? The turbo 350 and turbo 400 are GM transmissions that were used from 1969 through 1979 for the TH-350 and 1964 through 1990 for the TH-400. com, the official website for Car Craft Magazine. The Chevy 350 is a smaller, lighter engine that is known for its reliability and versatility. The 400 has a taller deck height (10. 485”- 2. Sep 22, 2022 · C1 & C2 Corvettes - stock 350 rods vs 400 rods in my 400 build - I've heard varying comments about the benefits of using 350 rods in my 400 509 block build rather then the shorter 400 rods. In design, the pontiac 350 is like a stroked chevy 307, and the pontiac 400 has a lot in common with the chevy 400 from a bore/stroke ratio standpoint. I can use the dough for new heads. The (stock, cast) 400 crank is still plenty strong enough when the mains are cut down to the 350 size, and the 400 main bulkheads are significantly weaker than the 350's. Myvintageiron7512 157K subscribers Subscribed Jun 11, 2003 · 383 vs 400 vs 350 vs 327 By Guest thepenguin99 June 11, 2003 in Gen I & II Chevy V8 Tech Board Oct 31, 2010 · The 350 and 400 are very different. Learn about the 5. A 4oo block with a 3" stroke displaces 321 cu. Oct 22, 2013 · C4 Tech/Performance - SBC 350/400 difference - Excuse my ignorance regarding GM block design. 65? i'm ASSuming larger main bearing equals larger main journals on the crank----which means more strength for the crank? BUT more friction (how much The only significant difference between the Chevrolet 305 and 350 cubic-inch engines is the size of the cylinder bore. With an engine displacement that typically ranges from 262 to 400 cubic inches, the small block Chevy can be tuned to deliver impressive power Jan 17, 2025 · SBC 1985 and older (302, 305, 327, 350, 400) are two piece rear main seal SBC 1986 and newer (305/5. if the 400 is a better motor im going motor swap them before he sells it . 58” diameter bolt circle and a 2. 400's are great blocks and have potential of being extreme monsters, IF YOU DO YOUR HOMEWORK. Motor ran like poop with the 350 plate. Jun 11, 2013 · Shift points were reasonable, not too early, let me use all the RPM the 400 engine had. May 1, 2011 · We build a 400ci Small Block Chevy for $2500. D. Jan 7, 2007 · although there is no substitute for cubes I've been hearing that the 400 small block is plagued with overheating problems because the cylinder walls are to thick. Feb 22, 2015 · Will stock crank and 350 rods hold up at 6000-6200 RPM? I'd love to pop for rotating assembly but I hate to have good parts go to scrap. Chevy 396/402 big block performance, history, specs, and variants. Now, if you're using an aftermarket block, no question that 400 cubes will make more torque than 383 or 350. Aug 24, 2025 · The 400 would have been fine, if not better, if it'd kept the 350 main size. The small block Chevrolet engine, known for its versatility and durability, has long been a favorite foundation for performance builds. Its not the rockers. 125 inch bore and a 3. net: Various General Motors automatic transmission dimensions. My friend has a 400 short block he took from a truck. The 400’s flywheel is larger and thicker, which can cause starter misalignment and clutch fitment problems on a 350 engine. i. 400 flywheel - Hello all, I have a 1975 vette that someone put a Chevy SB 400 in. A 400 c. between a smallblock 350 and 400? Jun 12, 2023 · The main difference between a 350 and 400 Harmonic balancer is the diameter of the balancer itself. You can have a 400 INTERNALLY balanced, but that can be somewhat expensive to have done Sep 11, 2025 · The TH350 and TH400 are GM’s most legendary transmissions. thank you:) :). Will some of the components of my engine (Eld Performer Intake, hooker headers) work on the 400? 3. Dec 27, 2001 · C4 Tech/Performance - 400 sbc VS. Note how the balancer weight is not consistent around the circumference. 876 bores while the 400 has 4. 025 inches). TH400 Performance: Which Transmission Offers Better Power and Reliability? Discover the differences and similarities between these GM transmissions. Apr 15, 2008 · A 400 balancer has a large indentation in the outer rim of the balancer about 1/4-1/3 the circumference of the outer rim. and with a 3. Oct 10, 2009 · 400sbc vs 350sbc FAQ's and Info SBC/BBC To distinguish a 400 from a 350 small block Chevy, check the engine block casting numbers usually found on the passenger side near the cylinder head. 383 I have a 388 (. 121" bores. inch. 030", if at all possible . most people who have had them love them. Jan 23, 2006 · Look that number up and it'll tell you what you have. The indentation is pretty sizeable and easy to recognize. A 2nd gen engine mount will not work as in '69 they switched to a tall and narrow mount. May 8, 2021 · Turbo 350 vs 400 Jump to Latest 8. in. As mentioned above the Chevy and Pontiac motors may have used similar (but likely slightly different) carbs, distibutors, starters, fans and alternators but the basic engine block, heads, intake manifolds, exhaust manifolds and Jan 3, 2005 · PONTIAC ENGINE WEIGHT VS SBC OR BBC Pontiac - Street Jan 29, 2016 · We show you how to choose the correct carburetor for five different engine horsepower combinations. Anchor part No. Feb 13, 2024 · Both Pontiac and Chevrolet employed "400"-series engines under the General Motors banner, but they were not nearly the same engine in design and purpose. The 400 crank has a longer stroke and larger mains than the 350 does, and is an EXTERNALLY balanced engine, whereas the 350 is internally balanced. I guess for durability. Both transmissions are celebrated for their durability, performance, and Apr 8, 2025 · However, much like the 350 SBC is the main engine people consider on the Gen I/Gen II eras, the 5. It said it would make it a 410-418 if you did this. Learn the differences in strength, weight, performance, and applications. Aug 21, 2020 · This is a harmonic balancer for a 400 c. turbo 400 power loss, the th400 uses more power during operation than the turbo 350. boring, cleaning, 0 deck, etc. And the "400" size of 2. 5K views 6 replies 5 participants last post by TheHotrodHandyman May 8, 2021 Fif-d5 Discussion starter Nov 17, 2022 · Chevy 350 small block engine specs, vehicle applications, performance, and history. Initially designed as a high torque/low performance engine, the 400 used a 4. the 350 head gaskets are made for a 4. The 400 is external balanced. Sep 20, 2002 · The Chevy 350 may not bolt up to the tranny (BOP used a different flange pattern I believe). The TH-350 was a low-torque transmission that was used in heavy cars. I read in a chevy hi po magazine that they can make upwards of 450 hp with a good set of heads and cam. 6:1. Power capability, weights, dimensions, valvetrain, displacements, model years. Mar 5, 2016 · 350 main has a smaller bearing, less friction area perhaps? 400 main would be stronger? It seems a lot of 410 sprintcar engines use a 400 main. Oct 7, 2019 · An engine guide that will help determine if an internal or external balanced flexplate is needed for your engine. Will the Mar 4, 2024 · We start with a nice basic Chevy 350 build parts list and move through such options as 400 hp 350 Chevy recipe, 500 hp 350 Chevy recipe, and even a 350 SBC turbo build. Here is how to tell a 350 from a 305. We'll break them all down. 7L) are one piece rear main seal Small blocks with two-piece rear main seal have a 3. The TH-400 was a Apr 25, 2025 · The quest to build a 400 horsepower small block Chevy is a classic ambition for many hot rodders and car enthusiasts. 155" with a 327 stroke and it displaces 353 cu. I did it on a limited budget so it is by no means a high performance engine but it was a definite improvement over the crate 350 that the PO had in it. Jan 18, 2010 · What are the outside physical diff. I do not want to overbore more than . You MUST use a flywheel and harmonic balancer made for a 400, as they have external counterweights to help with balance. Of course, I won't skimp on block prep, i. everybody hates 400 because they have heard this or that about cooling. Jan 25, 2019 · The 350 flex plate on a 400 will be an issue. My Mortan Garage ChevelleStuff. Oct 18, 2008 · The 350 and 400 share the same 3. Most 350 cubic inch engines are internally balanced whereas the 400 engines are not. Thanks. This engine would eventually be used in passenger cars and trucks in nearly every imaginable state of tune. externally-balanced small-block Chevy. The Chevy 400 small block flywheel is generally not compatible with the Chevy 350 due to differences in bolt patterns and ring gear size. The extra weight is the external balance. e. The 400 cubic inch engine is externally balanced Jan 4, 2021 · two combinations were not listed. This is capable of up to 265 horsepower when kept in stock condition. We’ll save the 400 SBC vs 6. Jan 19, 2009 · how to tell a 350 from a 400 The 1973 - 1987 Chevrolet & GMC Squarebody Pickups Message Board Apr 25, 2024 · Kickstart your understanding of Big Block Vs. Confirm by measuring deck height or bore size for May 1, 2005 · The Chevy 377 De-Stroker Jim RussoRedding, CAI'm going to build an engine for my '67 Biscayne, and I have several options available but I'm interested in doing a 400 small-block with a 350 crank. You will also need more cam to get a rougher, thumpier, idle you want. 0 LS for another time, as the 5. Its formal name is the Super Turbine 400. You can tell a 350 from a 400 by the balancer. Most people refer to the 350 as large journal even though Chris' is correct in his description. Jun 13, 2007 · Which & Why: 350 vs. Oct 22, 2025 · Battle of the Classics — TH350 vs. My question is, how big is the chevy 350 flywheel and can I just swap out Feb 13, 2007 · What benefit would there be to building a 302 over a 350 or a 327 over a 350? Revs? I have a stash of parts and am wondering what to do with them. This guide will compare the chevy 400 small block vs 350 engines to help you find the better option. it would be like putting a 350 head gasket on a 305, I would not do it, just my opinion. Small Block Engines with key differences that will change how you view engine performance. Also if someone can chime in with the length of a 1972 Muncie 4 Jun 8, 2011 · Depends on what Harmonic balancer you have. 180 heads on the 383 may aid torque but hinder higher rpm. While both offer impressive performance and durability, they have significant differences in Dec 14, 2005 · Usually there is a displacement difference between SB and BB but as you point out Chevy SBs go up to about 400 Ci (I’ve seen aftermarket 454 SB’s in the magazines) and BBs are above 400. can you give me some tips , on how can i get the most power out of the 400. TH350 vs. Jul 27, 2007 · 400 blocks have weaker (thinner) cylinder walls, the 4 bolt version is weaker than a 350 4 bolt in the main webs, and 400's usually run hot in a street car. 5 to 1 tested 10-11-24 Cordova dragstrip Compared to 400 Vortec headed sbc tested last year and a 350 Vortec headed sbc tested last year. Apr 21, 2009 · which is better a 400 sbc or a 350 sbc . 400 sbc how to I. (Image/Jeff Smith) I have a Camaro with a 420 The L31 heads from the late-model 350 Vortec engine, introduced early in 1995, is the other type of cylinder head you need to look for on the used market. My motor is: flat top pistons, Eagle rotating assembly, Herbert soild roller . inches. Questions: 1. 7L small block LT1, LT4, LT5 and more. Most accessories will fit either engine. is this true? Apr 23, 2007 · Depending on which 400 block and how you build it, you may be able to distinguish it as a 400 and not a 350. There is nothing rare about a 327, it was made for 7 years--you want rare, how about a 1975-76 262"? May 1, 2025 · Why was the Pontiac 350 phased out for the Chevy 350? Discover the key differences, performance, and advantages between these iconic GM small-block V8 engines. Comparing a 400 small block engine to a 350 engine, the 400 offers greater displacement and potentially more power. I am a little confused by the differences between them though. The major difference is found in the casting numbers and the way they are balanced. externally balance flexplate would have weighs welded to the flexplate while a neutral balance flexplate would not have any added weight. Apr 3, 2025 · Have you ever wondered what the difference was between the Chevy 400 small block and the 350? Let’s dig into each and see what makes these motors unique. 00 inches). Only at www. 4. Jul 9, 2015 · It was 1955 when Ed Cole’s Chevrolet engineering group got together to build a more powerful engine for the new Corvette. At the time, the Corvette’s engine was a 165 horsepower six cylinder. 2267 To clear an oversize (performance) swaybar you probably need to shim down the swaybar by installing 1/4" plate between swaybar mount and frame. 350/383/396 - What are the pros and cons of using a 400 block rather than a 350 block? I know about the steam holes, but what else? Chevy 357 World Sportsman II heads 12. 125 cyl or larger for bore jobs. (120 words) The Turbo 350 and Turbo 400 are two popular automatic transmissions used in high-performance vehicles. But first, let’s briefly discuss the two small block engines. I am aware of the 383 vs 406 Arguments . For many enthusiasts, the choice often comes down to two incredible options from General Motors: the TH350 and the TH400. 0L, 350/5. Plus, a bunch o Apr 9, 2010 · Is your friend's crank a 350 or 400 crank. 350 and 400 Chevy what's the difference. We would like to show you a description here but the site won’t allow us. Dec 22, 2006 · as far as a 350 mopping up a 400 mabe if the 350 was 060 over and @ 10:1 vs a stock bore 400 thats 7. The replacement dreamed up and built by Ed Cole and his team, was an all-new small block V8 with 265 cubic inches that went from a drawing to production in just 15 weeks. 8" = 350 engine mount to clear stock swaybar. Apr 1, 2018 · There are many differences between the TH350 vs 700R4. A 350 Harmonic balancer has a smaller diameter than a 400 Harmonic balancer. Is it worth the bother? Thanks May 4, 2023 · Chevy 396 big block specs, applications, engines, RPO, and horsepower. TH400: Which Transmission is Right for Your Build? When it comes to building or upgrading your vehicle, one of the most important decisions you’ll encounter is which transmission to choose. Mar 12, 2025 · Discover the best Chevy 350 crate engine options, performance specs, and expert insights for your next automotive project. 56 inch long connecting rods. Nov 25, 2021 · Can we get in-depth regarding main bearing sizes? Specifically with the SBC----we have the "350" size, 2. 450 diameter of the stock 350 crank, the 400 crank will pop right into a 350 block, adding some 28 cubes in the process. Both transmissions hail from General Motors' legendary Turbo Hydramatic family, and each has carved out its own loyal following. By grinding this down to the 2. Chevrolet small-block engine (first- and second-generation)The Chevrolet small-block engine is a series of gasoline -powered V8 automobile engines, produced by the Chevrolet division of General Motors in two overlapping generations between 1954 and 2003, using the same basic engine block. Jan 25, 2023 · I would not use the 400 head gaskets with steam holes on a 350 block, the 400 head gasket are made to fit 4. The last 400 block I built was a 2 bolt with decent cylinder walls. 60 over) - the 180 runner heads are a little small for the 383. Does a 400 get some kind of balance job like a 350, even though they are externally balanced? Feb 27, 2023 · The 1967 Camaro also brought the world the first 350-cubic-inch small-block Chevy V-8. some of the differences between a sbc 400 and other sbc's a few of the things to look at when rebuilding a sb 400, a few tips on rebuilding a 400 Jan 11, 2023 · Over several generations of small block Chevy (and big block Chevy) engines there have been several changes that dictate what flexplate works with them. When deciding between these options, consider your specific performance needs and budget constraints. Feb 4, 2012 · 350 vs. 400 SB got to be very low on oil pressure, tended to run a little hot, so I yanked it out. Jul 17, 2023 · Dive into a detailed comparison of the Pontiac 400 and Chevy 400 engines. Its odd Texas-shaped oil pan distinguishes it from the Turbo 350. 2 inches) compared to the 350 (9. Ask me how I know Had to go back, find the 400 plate I had chunked and put it on. TH400 When it comes to classic muscle cars, the debate between the TH350 and TH400 transmissions has fueled gearhead discussions for decades. As long as you have steamholes in the right spot in the heads, no other Oct 11, 2004 · The problem with "More cubes" is that the 400 block can be more fragile than the 350 block. I am thinking about replacing the tranny and Oct 22, 2025 · TH350 vs. They include gearing, weight, length, locking torque converter, overdrive and more. There ain't nothing like torque! The 350 simply ain't gonna have it, roller cam or not. For the 1965 model year, Oldsmobiles, Chevrolets and Pontiacs were equipped with the Turbo 400. . 25: stroke displaces 348 cu. But which is better for your build — the lightweight, versatile TH350, or the heavy Mar 21, 2009 · C3 Tech/Performance - 350 flywheel vs. For 67 Aug 18, 2005 · I read in a magazine that sb 350 push rods are longer than 400 rods and you could put them in a sb 400. vlff 4q3 egcqu sxw uiuuz c03 tl7tcu gufqcgt ro4 q5137w