Chevy 991 head specs. Clearwater Cylinder Head Inc.

Chevy 991 head specs. So, in order to fix this common cracking issue, you’ll have to get a replacement for the cracked cylinder heads. Unless they are completely machined and have the correct valve springs for your camshaft, Find many great new & used options and get the best deals for 350 Chevy 991 76cc Cylinder Heads 1986 & Older Early 1. He also didn't address all that needed to be known about the Vortec heads, but he got close. 3917291. they give years and other info but no runner volumes. So I have a pair of #3998991 heads laying around, and as some of you may know I'm building a mild 350, bored . The heads are useable as is, but they're small from what I've read. 76 cc combustion chambers. Other than the cam lobe all the other items including pitons are in very good shape. Small Block Casting numbers Apr 7, 2017 · The 991 are small 1. i think they are 75cc. We love Muscle Cars. Round push rod holes. . Jun 28, 2014 · With STD-LD block series(194-230-250) - the front to head bolts should be torqued to only 85 pounds. Are these decent flowing heads for a DD motor, or should I drop some May 15, 2008 · The 991 head is a so, so SMOGer with 75 cc chambers or more. Fresh valve job on old parts or new valves, guides, springs, etc ? Ports been messed with or still untouched ? 2. Pontiac V8 Engine. ) Torque (Nm) Step 1: 22: 30: Step 2: 45: 61: Jul 12, 2012 · If a "decent" shop did a conversion from the 1. 4 comp on pump gas with iron heads and that spec cam will be creating a crank buster!! Top. Jan 24, 2012 · chevy aluminum heads 10088113. 4L heads are heavy and don’t offer great flow. Standard Gen-I small-block Chevy heads position the valves at a 23-degree angle to the deck. It takes a flat top piston to get the compression up, the ports and valves are OK, pretty much standard 4 inch Mar 14, 2003 · YEARS: CASTING# CID: Intake : Exhaust: CC : COMMENTS: 1971-75: 330545 : 307,350 : 1. (Be sure water pump is in place prior to torquing the head. 94 Intake Springs at the best online prices at eBay! Free shipping for many products! Apr 7, 2005 · The 991 heads are originally off of a 71 and later 350 truck motor. 84 valves. Oct 21, 2009 · Around here alot depends on what you mean by ready to bolt on, condition, etc. Jun 22, 2009 · chevy head casting numbers for Camaro, Corvette and stovebolt trucks Chevy Silverado 1500 5. com then to links then chevy casting #'s all blocks and heads that chevy made are listed there. In 1989, Chevy introduced the 18 Apr 7, 2017 · The 991 are small 1. 94 or 2. Jul 2, 2019 · Repairing a worn down Chevy 350’s cylinder heads would not break your bank, therefore don’t give up on your engine. Chevy Silverado 1500 5. This ensures proper sealing and prevents any potential issues in the engine’s performance. Nov 2, 2006 · The chambers should be 75 cc's and the valves could be 1. The correct torque ensures proper clamping force, preventing head gasket failure and maintaining engine performance. Come join the discussion about restorations, builds, performance, modifications, classifieds, troubleshooting, maintenance, and more! Show Less . Port shape, chamber design, and valve size [] Oct 4, 2024 · 1 History and Evolution of Chevrolet Cylinder Heads; 2 Technical Specifications and Identification. 005-. another head that was patterned in the same mold but a little heavier casting is the 991/993 truck heads. 94 intake valves ? With the large variety of really good aftermarket smallblock heads the last few years prices on the old double hump heads has gone down a bit. If you’re a stranger to these block engines, read my summary on 400 and 350 small blocks. 3. Jan 6, 2024 · Head Bolt Torque Specifications for the 4. How well did it perform in competition? The owner won almost every round of racing and the championship. 1 Understanding Casting Numbers and Dates; 2. Heads have the center bolt through valve cover. 7 Vortec. The 193's are the "swirl port" head that has half the intake port approach to the valve bowl cast blocked off, even though they have the larger 1. 72" intake valves and large 76 cc open chambers. Crafted to exceed OEM specifications, these cylinder heads are designed to be the perfect fit for your 6. so anyways I was hoping somebody could give me some info on 882 heads. The revised 461 heads were available starting in 1964 models with either 1. When installing the cylinder head on a Small Block Chevy engine using ARP head bolts, it is crucial to follow the recommended torque specifications. 060 over. Have a new set of valves #1 · Jul 12, 2012. lbs. Mike Feudo. Cast Iron; 3 Performance and Upgrades. 72 : 1. It isn’t hard to notice 882 heads are 400ci small blocks with a pretty consistent 200 CFM rating in a sports car. Apply a small amount of engine oil to the threads and the washer face of each head bolt. Save Share Detailed specs and features for the Used 1991 Chevrolet S-10 Blazer including dimensions, horsepower, engine, capacity, fuel economy, transmission, engine type, cylinders, drivetrain and more. 94 : 1. An over the counter only part. M. I also have a set of 993's off a 72 350. The date code is irrelevant unless you’re really trying to re-create a piece that matches some original documents and sales dates. (See page 142 for more on this head, a build spec, and power curve. I've heard these are actually descent heads and they flow ok considering they are off a 305. ) Racing Head Services. They can be opened up for good port velocity but they are all in by 5000 to 6000 on small engines and choke bigger engines. Jan 6, 2024 · 350 Chevy Head Bolt Torque Specifications. 02 or 1. 02. Step 2 45 Ft/Lbs. 94 valves and the 76cc chambers. 436 posts Jun 27, 2010 · Remember that the '461X heads were used in 1961, 1962 and 1963 with valve sizes 1. 5cc on average bigger. Manufactured by Chevrolet, this Jan 22, 2011 · I'm building a 496 BBC and have 2 sets of heads, 781 ovals and 990 rects. Apr 3, 2002 · Machine shop suggested a "functional replacement head" would be the 333882's which were used on Corvette's 74-77 (Lo-Po and Hi-Po models) and according to one of those Jul 14, 2006 · Hey guys I'm trying to fill out the cam recomendation form for Comp cams but I don't know the runner volume of these heads any help would be greatly appreciated. Start by cleaning the cylinder head bolt holes and the bolts themselves to ensure a clean and accurate torque reading. Mar 5, 2009 · Yes youngsters, there is a "Turbo" head for SBC. 3L truck engines. When using studs follow the manufacturer's installation and lubrication directions. Chevrolet engines (not centerbolt). I'm afraid the heads might need alot of work. When working on the cylinder heads of a 1998 Chevy 5. THIS IS FOR A PAIR OF CYLINDER HEADS. Pontiac V8 Engine – The engine that sparked the Muscle Car Era . 75" Intake Valve - 882/993 Cylinder Head, a high-quality replacement part that exceeds OEM specifications. On your 292 all the head bolts are torqued to 95 Apr 14, 2004 · PDQ, and not only one of a set of heads. 7 engine, follow these steps: 1. supposedly with 2. 50 only. 4/06 - RS/mc 1 of 4 ©2006 Edelbrock Corporation Brochure #63-0072 PERFORMER AND PERFORMER RPM CYLINDER HEADS For Small-Block Chevrolet V8 Engines Catalog #s 60619, 60639, 60659, 60719, 60739, 60759, 60849, 60589, 606869, 60879, 60889, 60899, May 11, 2007 · head specs gm 3998991 307/350 68-79 1 ENGINE CHEVY 57-87 V8 262-400 ALSO 87-95 TRUCK VALVE SETTING: . They have 14mm angle plugs, 2. 165cc sounds right but not for sure. (CCH) is a reputable, experienced (over 25 years) dealer. Here is a quick comparison chart highlighting the significant specifications of 906 and 906 Vs. By following the manufacturer’s recommended torque values and using a systematic approach, you can confidently torque the head bolts and ensure a reliable engine performance. I also Apr 12, 2006 · APPLICATIONS: Performer #60659, 60759 and 60909: Cylinder Heads are designed for 1986 & earlier 302, 327, 350, and 400 c. 94"intake valve, they are worthless Apr 12, 2006 · Performer/Performer RPM Small Block Chevrolet Cylinder Heads Rev. Nov 10, 2008 · Im sure there are many posts on this but I tried the search button like 9 times and it wouldn't work. Dec 12, 2018 · Small-Block Chevy Gen-I Cylinder Heads. Feb 24, 2023 · Chevrolet 327 Engine Car Applications. I'm not planning on using the heads I've got some aftemarket heads but I wanna know the combustion chamber size so I can figure the compression ratio with my new heads. 1 Selecting the Right Heads for Your Chevy Oct 16, 2014 · He didn't mention 462 heads at all, which are virtually the same as a 461. Apr 19, 2024 · Choosing big-block cylinder heads depends entirely on the application. I talked my friend into buying a 78 malibu(I know its not a camaro, but he got it quite cheap) and would like to help him get it around 375 hp or a little Mar 21, 2024 · This Tech Tip is from the full book: HIGH-PERFORMANCE CHEVY SMALL-BLOCK CYLINDER HEADS. 991@97 mph (with old 482 BBC engine/combo) (15) Car ran a 6 . Save Share best time so far in the 1/8 July 8 2023 6. Chamber size, valve sizes, intake cc, etc. Find many great new & used options and get the best deals for GM Chevy Cylinder Head Part 3998991 Completely Reworked at the best online prices at eBay! Free shipping for many products! May 12, 2023 · The 906 and 062 Vortec heads are two popular cylinder head options used in small-block Chevy engines. 02/1. Jul 11, 2005 · The 291's are the old double humps with 1. 3L Cylinder Head Torque Specs (M11): 22 ft-lbs + 90° + 70° Timing Chain and Camshaft Installation On the Chevy 5. 3 Vortec engine, it is essential to have the correct torque specifications for the head bolts. 6. These heads also have 1. Step 1 25 Ft/Lbs. Engine: 396: 402: Production Years: 1965-1970: 1970-1973: Aspiration: Natural Aspiration: Natural Aspiration: Displacement: 396 cid (6. The L84 version with fuel injection held the record for the most powerful factory small-block Corvette until the 1990 ZR-1 would match it, and then surpass it in Oct 14, 2022 · Chevy 396 Big Block Specs and Years 396 and 402 Big Block Specs. 7 Vortec engine, it is crucial to tighten the head bolts to the correct torque specifications. 7L 350ci V8 1. The torque specifications for the head bolts on a 2. Jun 27, 2023 · 993 Chevy Heads And Chevy 882 Head Specs Comparison. I'm guessing Apr 25, 2007 · hey guys, i have a pair of 991 casting heads for a sbc. 305 Specs, Information, & Performance The Birds Nest :: The Nest :: Firebird Forum 1967-Today :: 3rd Generation Birds 1982-1992 :: 3rd Generation Garage 1982-1992 Page 1 of 1 1999 Chevy 5. Knowing the correct torque specifications for the head bolts on your 07 Chevy 5. sorry nitro_baller4692 . 7 engine, it is crucial to tighten the head bolts to the correct torque specifications. i. Home; GM. 520`inch lift. i know that they are rec port/closed chamber, but thats about all i can find. 00 @ 204+ @ 3800# Save Share Like. 5 days ago · 317 Heads Specifications. Step 3 65 Ft/Lbs. 3 OHV engine the timing system is ran by the use of a chain. This casting # has been used in many different versions of this aluminum 18′ and 15′ Introducing our 71-77 Chevy 5. Just make sure you consult professionals to view all Chevy 350 cylinder heads for sale. Apr 25, 2007 · 991 sbc head castings. You can use the Sep 10, 2009 · Seems like about a dozen years ago, I had a copy of Chevy High Performance magazine that had a great chart in it that showed the runner volume, combustion chamber CC and other vital specs of SBC heads. 317 6. 991@97 mph at Luskville dragway - YouTube. 5001 - 1971-76: 333881 : 350 Nov 22, 2009 · Heads are 3998991's This seems to be a low compression smogger type motor. just about the worst smogger head combination, suitable only for bone stockers or use as boat anchors Jan 3, 2010 · Use these casting numbers to identify the heads you have. 6L - 400ci - V8 engine. If restoration is your goal, your choice is limited to locating the correct casting for your original engine. Also the 991 head will have a 3/8 stem exhaust valve. Procedure: To properly torque the head bolts on the 1998 Chevy 5. 3 Vortec Chevy Engine When it comes to working on the 4. chevyracer8262 New Member Posts: 31 Joined: Sun Nov 01, 2009 1:50 am Location: MS. Both are presently stock, no porting but have been cleaned and maged. While 906 and 062 Vortec Heads share some similarities, there are also some notable differences. 50" or 2. Failure to fix this issue can result in severe engine damage that can be costly to repair. Dec 2, 2019 · Small Block Chevy Head Bolt Torque Specifications. 2. Specs for the 1970-1976 big block 454 cid engine are as follows: Engine: Chevrolet 454 Big Block Displacement: Additionally, Chevy 7. Some People do only 1 or 2 steps to reach the final torque. The do make great torque. im gonna try to sell them, were they any good? how much would they bring? thanks guys. Heads fit 1987 - 1995 only, TPI and TBI intakes. The later 461 or 462 heads would be my choice for a nostalgic look and high performance. Clearwater Cylinder Head Inc. 020" they also "flycut" the side wall to OEM specs! Most shops didn't bother! Thanks, I would not spend $150 on any set of used stock Chevy heads. 3 engine is essential for proper engine assembly and maintenance. 007" to get the two heads much closer in chamber size. 5001 : 74 : 1971-73: 330862 : 400 : 1. The most common problem with the 862 cylinder heads is that they crack in the long run, allowing coolant to flow into the oil. Regarding 993 Chevy heads, these castings with valve sizes were either 1. Feb 12, 2011 · Killeen, TX. different styles depending on heads and stud diameters. For Head Studs or aftermarket bolts CHECK YOUR INSTRUCTIONS, SBC studs are available in a ton of . 5 L) 402 cid (6. Aluminum, LT5, ZR1, DOHC, 32-Valve, drivers Side. You can use the The big-block Chevy’s canted valve heads are largely responsible for the tremendous power capability of the Rat motor and its continued popularity. just about the worst smogger head combination, suitable only for bone stockers or use as boat anchors or door stops. The 291 is a SUPER Casting providing you follow Grump's Specs; in other words, you have to work them in order to increase flow with cams over . But he said that he had never been able to make a clean pass with this engine even with that winning record. Jump to Latest A forum community dedicated to Chevrolet Chevelle owners and enthusiasts. 0L Truck Castings; Valve Size: Intake – 2. 3 Materials and Construction: Aluminum vs. SHARE THIS ARTICLE: Please feel free to share this post on Facebook or any automotive Forums or blogs you read. Lastly I have a set of 305 HO 601 heads with 1. For a comprehensive guide on this entire subject, you can visit this link: LEARN MORE ABOUT THIS BOOK HERE . Oct 12, 2011 · Hello again I posted a question tonight about intake selections and a helpful member replied but mentioned that my 990 heads were considered large. I thought 991 were basically junk am I correct? Jul 11, 2005 · I was wondering out of the 3 heads which would be the better choice. YOU WILL NEED TO LET US KNOW IF YOU NEED THE Nov 2, 2005 · I need help finding specs on theses heads. Below is a table outlining the ARP SBC head Head Bolt Torque Specifications for a 1998 Chevy 5. 94 valves. Henry Ford, on the stock market May 4, 2023 · Chevy 454 Engine Specs. 50 or 2. 02, 1. Here we are with another head question for my budget de-smogger build. 8L and 5. RHS has some excellent Chevy big-block heads. The screw in studs and plates are a add on. ) 5. Really the only difference is the 991's have assy holes and your don't. Before I spent a nickel on these heads, I would call around to several machine shops and have them give you estimates on all the work it will take to bring them up to specs. Combustion chamber size. Found a set of heads . Jump to Latest its not worth the $$$ if you don't already have a set as a $400 purchase plus 800-1000 in porting to bring them up to spec isn't worth it, the small chambers are nice however. To wit, I had one head that measured 1. And I'm not sure that a 993 head is much better than an 882. Casting number is 191 or 193 on these heads. Part # 3965784, casting number 340292. 60". Feb 23, 2007 · They are a great head for 283s and even a mild 327. I want to Mar 6, 2007 · C3 Tech/Performance - 991 Heads - I took the valve cover off of the 400 I have and the heads are a 991 casting. Re: Chevy 186 head flow questions. DON'T ASSUME! Dec 8, 2005 · You`ll notice some more power due to the compression but if you really want to run stock chevy heads, find some vortecs. If you’re looking for more power then the cylinder head is a great thing to address regardless of problems. To ensure the proper functioning and longevity of the 1999 Chevy 5. 2 Chevy engine are crucial to ensure proper installation and prevent any potential issues. They will work fine on a 307. Proper torque ensures that the head bolts are tightened to the appropriate level, providing a secure and reliable seal between the cylinder head and engine block. and any thoughts/opinions on them. 94"/1. The 414 Turbo Flow, I believe, was a Late 69/70 Vette & Z28 LT I 370Hp 350 Head, favored by Jenkins ? Description Professionally rebuilt pair of Small Block Chevrolet cylinder heads. 940" to the 2. 02"/1. 7 Head Bolt Torque Specs. With the part number ALL-20201, sourcing these high-quality heads is straightforward. 8L engine. However, 062 has slightly larger valves than 906 Vortec Heads. Any help would be great 1956 Chevy Bel-Air 7. Jul 14, 2006 · Question on 991 Heads? Jump to Latest i went to 1320. May 19, 2010 · I've chosen to run a pair of Chevy 186 fulie heads with 2. The original head design is often referred to as having a 26-degree valve angle, although this intake valve angle of inclination is only one of four angles needed to numerically describe the big-block’s valve angles. The valve size and combustion camber is the same. 94/1. From 1962–1969, Chevy used the 327 engine in a variety of different passenger trucks and cars. . 2 days ago · 826 Heads Common Problem. Developed in 1975, the best SBC head of the era. Here are the recommended torque values for the head bolts: Step Torque (ft. 60 valve seats, no heat riser, large ports, 66cc chambers, screw in studs, new design inlet port Find 1993 CHEVROLET 5. Alright so I'm looking a 1971 Chevy 350 out of an El Camino and I'm trying to figure out the head specs i. 23 @ 196+ @ 3800# Best time to date-11/2019 7. So we dusted that one down an additional . 55; In 2010, Chevy began manufacturing 799 heads on the L20 4. 7L/350 Chevy small block Gen I Cylinder Heads and get Free Shipping on Orders Over $109 at Summit Racing! $5 Off Your $100 Mobile App Purchase - Get the App - Final Day! Vehicle/Engine Search Vehicle/Engine Search Make/Model Search Sep 8, 2012 · Chevy LG4 305 and L69 H. Is there a way to visually tell if these are May 11, 2007 · does anyone know where i can look to find specs on sbc heads casting # 3998991 they say gm 71 on them i'm tryin to find out factory specs cc's, valves,springs,rockers, ext. O. e. Particularly if they've been dusted in the past. 022 the valves completely closed and the piston at the highest point the "081" heads have about 1/8 inch between and the "991" heads are barely touching the piston but it's definatly touching but i dunno if Chevrolet Big Block Heads were offered in many different variations within their 51 years of production. 00, Exhaust – 1. Since you said you wanted to change valves, I suspect you have the smaller valve heads. Mar 21, 2024 · This Tech Tip is from the full book: HIGH-PERFORMANCE CHEVY SMALL-BLOCK CYLINDER HEADS. 60 valves, depending on application. Elevate your Chevy small block engine with our premium 71-82 Chevy SBC 400 882/997 Cylinder Head. Since their introduction, the 799 heads have demonstrated solid performance and efficiency on the 4. 2 Analyzing Different Chevrolet Cylinder Heads by Model and Year; 2. Big Block was produced 1958 to 2009. Chevrolet Big Block Tune-Up and Torque Specifications . d. Is that possible I dont know all the stuff guys know but they are heads stock from gm for a 454 how can the be to large for a 468 roller motor please post any and all thoughts this is a 71 nova 468 4spd 411 rear thanks ARP SBC Head Bolts Torque Specs. 6 L) Chevy big block heads came in two versions, with either rectangular or oval shaped ports. The 291's are the old double humps with 1. This reinforces the front and deck of the block. By following the recommended torque values and the step-by-step guide provided, you can ensure that the head bolts are tightened to the correct specifications, promoting a reliable and leak-free engine performance. :beers: Chevrolet Small Block Head Casting Numbers. Most notably were the 1962–1968 Corvette and 1967–1968 Camaro. 60" on this engine Running 10. And he didn't mention 487 heads, which are "pretty good" heads for a 76 cc head, though many are cracked. Hmmm thinking about it, it might have been as far back as the late '80s that they had that chart. When working on the 350 Chevy engine, it is crucial to follow the correct torque specifications for the head bolts. Feb 16, 2011 · The 291 is a Stock 8G GM 302 & 327 Head - NOT for 350, 383 or 400ci mills. Proper torque ensures that the head bolts are tightened to the manufacturer’s recommended specifications, preventing any potential issues such as leaks or engine damage. You may also like. "Turbo" is the nickname, like "Powerpack" or "Fuelie" is. isiu lblxzk ted jynasm oiq alf phxbbp phrub byxaoacw ljqgca