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Chevy 990 bbc heads?
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Chevy 990 bbc heads?
Thinking of going to a hotter plug. 70cc combustion chamber450"/1. Just came back from the machine shop after being shot blasted and magnafluxed for cracks. Conversely, a flat top or dished piston allows for a smoother flow. 290 & 049 heads have oval ports. Donors seeking a tax deduction for the money that they contributed to a charity will need the organization’s taxpayer identification (ID) number. If you install a good quality stainless valve you don't have that problem and don't need hard seats. What do you guys think, these will be a cheaper alternative to purchasing the $1300 Merlin Heads. The exhaust was very impressive creating an E/I ratio of 72%. Get the best deals for Bbc 990 Heads at eBay We have a great online selection at the lowest prices with Fast & Free shipping on many items! Find many great new & used options and get the best deals for BBC Cylinder Heads Rectangle Square Port 990 Big Chevy 454 MK IV Ls6 6272990 at the best online prices at eBay! Free shipping for many products! Edelbrock Performer RPM Cylinder Heads 60549. Feb 19, 2004 · This head offers the highest average intake port flow and the highest peak flow numbers. 2 posts · Joined 2007 I recently bought a set of NIB 3964291 cylinder heads. 900" Intake / Exhaust 1 Automotive Performance Carburetors, Cylinder Heads, Intake Manifolds. I found the extra bolt gaskets matched the manifold nicely with lots of sealing surface, however the bridge area would overhang the port in the head and not seal. New set of complete Aluminum Big Block Chevy Pro Comp Motorsport Heads. 5 with no other changes. i Can Also Change From 250 Valves If I. V8 C ylinder Head Casting Month Codes B - February D - April F - June. The BBC vortec heads needs double rotator eliminator kits both intake and exhaust needs them and check so they fit as supposed had to grind on the rotator eliminator so they bottomed out. The Ebay item number for the heads is: 160024789088 Rick. timing 18* initial, 38* total. Superior aftermarket oval-port heads are available from all major head suppliers in iron or aluminum. No cracks or repairs. 390-500 Big Block Chevy CNC JAILBIRD 390 Bare. problems across the valve seat and short turn curve on the #049's. Did some work about a year ago on 781 and 049 heads. It was a crate gm engine, we put a roller cam and a dominator on it with a single stage fogger system and in a 3300lb Camaro and it would run 80's all day long0's without nitrous. Open-chamber designs are larger and provide lower compression. 0 346 83% 82%. Fresh 3 angle Valve Job and spring install. It also is 118cc open chamber head. Free Shipping; Special Order. Automotive Machining, cylinder head rebuilding, engine building are the worst flowing design Chevy ever came out with (and the better versions were pretty weak suck at that). Find Cylinder Head Valvetrain Kits and get Free Shipping on Orders Over $109 at Summit Racing! $20 Off $250 / $40 Off $500 / $80. These heads were ported by Juan Mendoza at Flow Technology in Garden Grove and should be capable of producing 1. The 049's will easily make over 500hp on a typical 468 if they are done right G. 107 posts · Joined 2008 I'm looking at a pair of marine Part Number 14097088 990 replacement heads. 119cc open chambers. BBC Heads Ford Heads Hardware SBC Heads Aluminum Pulleys. Allow engine to cool for twelve hours before re-torquing. Cam is HFT 230@50 and. One head had a couple broken guides that will need replaced. Heres a pair of completely redone, all brand new BBC RECT PORT heads cast #6272990 (aka 990 heads). 25-inch stroker crank. The PB 1802 is a cast ported version of the PB 1800 capable of flowing over 480 cfm. 1968 Camaro SS 396 coupe L78 - now old school 468 big block. keep in mind the price is without the valve train components. Received 2,701 Likes on 1,722 Posts. The recommended compression would be from 95:1 with pump gas, taking advantage of the aluminum castings. M. The only reason that people say they are not worth using is that machine work is expensive and by the time you sink the money in 990 heads, you could buy aftermarket. Cruise never planned to mak. AFR 345cc Magnum BBC Cylinder Heads 2110-1 Cylinder Heads, CNC Chambers, Aluminum, Assembled, 121cc Chamber, 345cc Intake, Chevy, Big Block, Pair Assembled Big Block Chevy Aluminum Cylinder Head, 358CC Rectangle Port, 117CC Combustion Chamber, Each. The cast-iron Merlin series from World Products has been one of the most popular heads for retrofit service on all big-blocks up to and including 496-, 502-, and 540-ci displacements. That is a tiny cam in a 496, the 325cc heads are big for such a low RPM operating range. Chevy Bbc 990 Cylinder Heads. Pulling the valve cover, the heads say 14096188. The current "bad-boy" Bowtie race head is PN 12363425 (casting number 14044861), a bare head with 380-cc intakes and valve seats for 288-inch valves. I ran Dart 325cc heads on my 509 and they were a little small on my 540. I'm running a set of OEM 990 heads (cast iron) so the heat issue will be different if you're using aluminum heads. And a tight fit at that. The extensive line of big-block competition heads runs from conventional siamesed port BMF (Beat More Fords?) heads that accept traditional Chevy pattern intake manifolds and stud-mount rocker arms, to … ProMaxx heads have started a revolution in the performance world. 6" exhaust valve inside the 70cc combustion chamber. 50 -1 compression, Tarantula intake with 4781 850 cfm dp Holley, Turbo 400 with a 9 inch Vega convertor, 4. 200" Intake / Exhaust. The 325cc magnum cylinder head intake runners and exhaust ports are partially CNC machined, while the combustion chambers are offered with partial or full CNC machining with a bowl blend. I was extremely happy with how the AFR head did and the 702 head. Open chamber BBC heads are usually abut 119cc. I wanna know on average how much they flow when you do port matching, bowl work, and three angle seats and a back cut of the. and 6272292 118cc, for 402 & 454 1972ish. As I understand it, Edelbrock also manufactures several heads for GM Performance, which have GM casting numbers and are legal for various classes of NHRA Stock and Super Stock competition 64 Chevelle Malibu Sport Coupe (original owner) car now has 427" BB, Jerico 5-spd, Dana 60 rear end. That part number you called out is for a 50cc domed piston. Ovate wire-type beehive valve springs with 1. I had a 454 with bone stock 990's. Nov 29, 2006 · For Sale: Rectangular Port Big Block Chevy Heads BRAND NEW springs good for Titanium retainers and 10deg locks. fyi, I had a big set of valves put in a set of 802's and got it to flow about 255 intake/199 exhaust at 0 TC Member # 4431. Ring grooves are 1/16, 1/16, 3/16. What do you guys think, these will be a cheaper alternative to purchasing the $1300 Merlin Heads. Expert Advice On Improving Your Home. A new probe alleges violation of foreign exchange rules India has brought a new case against the BBC for alleged violation of foreign exchange rules. When it comes to boosting the performance of your Big Block Chevy (BBC) engine, one component that can make a significant difference is the camshaft. Helping you find the best gutter guard companies for the job. Opens in a new window or tab To install our BBC heads on Mark V blocks, you will need to use our SM5233L and SM5233R Elite Series MLS head gaskets. Having a very similar port volume to the 990 head the 401 head flows dramatically better, especially at higher lifts. 15" intake valve and 1. Busted Knuckles said: Heads are parallel, block is series. It was a crate gm engine, we put a roller cam and a dominator on it with a single stage fogger system and in a 3300lb Camaro and it would run 80's all day long0's without nitrous. Cylinder Head Style: Assembled. halloween artwork Re: bbc 781 heads 01-30-04 10:17 AM - Post# 382381 In response to Doug_F Hi Doug , if you look closely at picture of chamber i posted link to and your heads you'll see compared to heads like #990 rect-port 's chambers, the #781 is GM's MOST cast unshrouded head they ever offered you don't have to do much unshrouding only very necessary at exh valve/quench pad area corner if you are going. The cast-iron Merlin series from World Products has been one of the most popular heads for retrofit service on all big-blocks up to and including 496-, 502-, and 540-ci displacements. These heads are bare and ready for your valve train setup. timing 18* initial, 38* total. The Darin Morgan - designed DM 500 (4. If you're outside of the United Kingdom then getting a good live feed of the Olympics isn't easy. The PB 1800 and PB 1801 were the original designs in this legendary series. The exhaust was very impressive creating an E/I ratio of 72%. Recommended for agressive street or street/strip applications with displacements up to 540 cubic inches, operating at or below 6800 RPM. 335/355 $ 4,395 We Start Every Custom Build Of Our Cylinder Heads With Brand New Dart Castings And Specifically Selected Components - These Heads Are Never "Factory Assembled"! Dart applied the same airflow technology developed in their championship-winning Pro Stock engine program to produce these state-of-the-art heads. supposedly the #781's cured or fixed exhaust seat cracking. Corey banned permanently on 3-6-20 for continued abuse. SuperNovaSS. 1967 Camaro RS/SS 396 coupe L35/M40 - 4 generation family project. Stock head bolts get torqued to 70 ft-lbs in three steps of 40, 55, and 70 ft-lbs. Actually the 291 and 292 are identical. Nov 30, 2001 · C3 Tech/Performance - Opinions On Big Block 990 Heads - I'm thinking about getting a set of #6272990 Rectangular Port Heads w/ 288 Valves. what i heard seems to bear out because i've see a bunch more. It's about cross section,velocity profiles and a bunch more that the big head guys can explain that makes the heads perform way better. The casting number is 12563934 and it has 7/16-inch accessory holes. We put a set of the fully CNC AFR 315 heads and then ran 565 @117. star trek strange new worlds 123movies 330864: '68 through '84 oval port, open chamber, 272-inch valves. It's about cross section,velocity profiles and a bunch more that the big head guys can explain that makes the heads perform way better. They are worth rebuilding and respond well to pocket porting, bowl blending and larger valves. 4 posts · Joined 2020 The base motor is an low mileage factory replacement from the 80's 454 (145 block) steel crank, dimple rod, 990 head. Jul 11, 2005 · guys, need your recommendation for spark plugs for my 468 BBC with the 990 heads. The HI PERF casting in the rear of the block is throwing me for a loop. That would be way easier then cutting spring pockets. at the best online prices at eBay! Free shipping for many products!. Although it shared the same basic architecture as the more pedestrian Mark IV big-blocks that powered countless Impalas, Caprices, and even trucks, in actuality it was a carefully concealed racing engine disguised as a somewhat streetable powerplant. is edelbrock performer with edelbrock performer intake going to 1980 camaro with 3. It's about cross section,velocity profiles and a bunch more that the big head guys can explain that makes the heads perform way better. Featuring fully CNC machined intake runners, exhaust ports and combustion chambers. Dart 310/325/345 Pro 1 Big Block Chevy Cylinder Heads Our Cylinder Head Assembly Is Never Just Rinse and Install, Watch This Video To See How We Assemble Your Heads BBC Big Block Chevy "X" Head Bolts 396 402 427 454 ORIGINAL GM USED L72 L78 LS6. If you already have a standard BBC head stud kit and are just looking for the 8 +. 088 would be peakier, AFR would be flatter curve but peak numbers pretty much the same Mfg Performance Partsstraubtechnologies wwwcom. some are running 10 second ET's with proper prep. Dec 27, 2002 · looking for information on flow numbr of stock 990 rect port heads (mine are just slighlty ported). I like them much better than the bigger 990 heads and they can out perform them too below. oriellys The … Superior aftermarket oval-port heads are available from all major head suppliers in iron or aluminum. Mar 10, 2021 · Looking through the GM catalog from 1989 it says Part Number 14096188 with a casting number of 6272990. 796 posts · Joined 2007 I am a huge fan of the old 990 heads. The extensive line of big-block competition heads runs from conventional siamesed port BMF (Beat More Fords?) heads that accept traditional Chevy pattern intake manifolds and stud-mount rocker arms, to symmetrical port heads for 5200-, and 5. Check out HowStuffWorks. The heads were removed from 496bbc and seem to be in good condition CHAMBER: 118cc19 / 1 990 bbc heads rectangle square. The casting number on each head is 3909802. 050 inch when the valve is fully open between each and every coil. The all new DN-9 represents the latest in cylinder head technology. Both are presently stock, no porting but have been cleaned and maged. The intake runner is far superior to the old 840 head. the merlins had too big of a intake runner (345cc)for my motor. 5 with no other changes. The AFR heads had about 2 less cc's than the 990's so maybe a little of the et came from a slight increase in compression.
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Might have to search in the performance section. Superior aftermarket oval-port heads are available from all major head suppliers in iron or aluminum. It’s official: a fully electric Chevy Corvette is coming — with new battery technology to boost its range, acceleration and efficiency. With flattops,, the 702 is the best,, street or strip. These heads work well across the full rpm range. Macho Member; Karma: +17/-0; Reactions:. 650 lift and below 7,000 rpm, after the minor mods are done. I had a 454 with bone stock 990's. Get the best deals for Bbc 990 Heads at eBay We have a great online selection at the lowest prices with Fast & Free shipping on many items! Find many great new & used options and get the best deals for BBC Cylinder Heads Rectangle Square Port 990 Big Chevy 454 MK IV Ls6 6272990 at the best online prices at eBay! Free shipping for many products! Edelbrock Performer RPM Cylinder Heads 60549. Call for Availability -. Lists them as coming on 70-78 402 and 454. Make it a condition of the sale that it pass magnafluxing. The 290 heads are 1969-70 396/402/427/454 oval port closed chambered heads. The intake valve was 288 Some work on the short turn to smooth out the mid lift turbulance. Get the best deals for Bbc 990 Heads at eBay We have a great online selection at the lowest prices with Fast & Free shipping on many items! Find many great new & used options and get the best deals for BBC Cylinder Heads Rectangle Square Port 990 Big Chevy 454 MK IV Ls6 6272990 at the best online prices at eBay! Free shipping for many products! Edelbrock Performer RPM Cylinder Heads 60549. Aftermarket studs usually get torqued to 60 ft-lbs, but check with the fastener manufacturer for specific. 4 posts · Joined 2011 I'm building a 496 BBC and have 2 sets of heads, 781 ovals and 990 rects. Jan 22, 2011 · I'm building a 496 BBC and have 2 sets of heads, 781 ovals and 990 rects. Fresh 3 angle Valve Job and spring install. Jan 22, 2011 · I'm building a 496 BBC and have 2 sets of heads, 781 ovals and 990 rects. Most flow numbers for CCH — Canadian Cylinder Head Technologies heads come from their Web Site updated Oct. megan rain bbc 50 -1 compression, Tarantula intake with 4781 850 cfm dp Holley, Turbo 400 with a 9 inch Vega convertor, 4. Pulling the valve cover, the heads say 14096188. Jan 11, 2013 · The 990 head is a 118cc open chamber rectangle head. 625 roller cam springs) Titanium retainers Milled. I ran Dart 325cc heads on my 509 and they were a little small on my 540. CR is 10:1, cam is 240 @050. GM corrected the misalignment issue around 67 or 68 I haven't pushed any. 72 posts · Joined 2007 8414 posts · Joined 2012 BBC heads come in rectangular port, oval port, and truck small 'peanut' oval ports. 20% CNC Ported Exhaust Ports. I had a 454 with bone stock 990's. It doesn't appear either head has been ported or cut. 3964292 listed for 454 112 cc, 1970. I have closed chamber pistons now (. I put the data in my desk top dyno 2000 and get following output: RPM HP Torq 2000 175 460 2500 232 488 3000 290 507 3500 354 531 4000 417 548 4500 473 552 5000. The cast-iron Merlin series from World Products has been one of the most popular heads for retrofit service on all big-blocks up to and including 496-, 502-, and 540-ci displacements. If you want alu heads Brodix race rites use same bolts/studs as oem heads this atleast saves you the cost of studs/bolts and they are among the cheapest decent BBC alu heads avaible. Actually the 291 and 292 are identical. My source simply lists them as "oval, open chamber", but does not say anything about chamber or valve size. Car shoppers, take note: The Chevy Volt has received a $4,400 price cut amid low sales and a new model. All the buttons you need ar. 106 posts · Joined 2007 I have ran both heads. used walk in coolers It’s official: a fully electric Chevy Corvette is coming — with new battery technology to boost its range, acceleration and efficiency. AFR 335cc Enforcer BBC Cylinder Heads 3001 Cylinder Head, 335cc Enforcer, Assembled, 2 Intake Valve, 10 Degree Locks, 1 Dual Valve Springs, Aluminum, Chevy, Big Block, Each. Then there is the spring which needs to maintain. AFR's 345cc Competition Ready Welterweight! If huge horsepower is what you are searching for, the 345 can certainly deliver. 3988920 heads 17K views 1 reply 2 participants last post by DoubleVision Nov 13, 2011 dueces are wild Discussion starter. New Ferrea Competition Plus valves, F2101P - int 1250" (around $400 just in valves) with NEW valve guides installed. 1488 heads work well with our PCE349. Put a 1/4" bead of black RTV on the front and back of engine overlapping the intake gasket a little Once this sets about ten minutes or so, gently set intake on and bolt to specifications Let this all set 24 hrs before putting antifreeze in and starting the car. I Am Running A 12. The 292 was indeed the "turbo" head. timing 18* initial, 38* total. After full upgrades with valves/porting it's probably a toss up, the 781/049 are more plentiful so maybe cheaper too. ASCS / SUPR Series Cylinder Heads To Fit Chevy - Ford - Mopar; V6 Chevrolet Compatible Heads Menu Toggle. The trick is to port match the bottom of the oval intake to the rec head on the base of the runner and up about 1/2 way up the port. Raylar big block Chevy / GMC cylinder heads out flow every 8. Big And Tall: Chevy's RS-X / ZZ632 Big-Block Cylinder Heads Are Huge. When larger engines (454 to 540ci) require added flow, choose the Merlin Rectangle Port cylinder heads. This may be helpful Servedio Cylinder Head Development 9:00am - 9:00pm EST Guru Shop 402 Chevy Big Block V8, Cylinder Heads and get Free Shipping on orders over $149 at Speedway Motors. Recommended for moderate street or street/strip big block Chevys with displacements up to 509 cubic inches, operating at or below 6500 RPM. I need help with valve spring height. Of all you guys that have experience big block chevy heads (mainly oval port). These budget-friendly heads are perfect for your 509 to 540 cu operating below 6,500 rpm. New Ferrea Competition Plus valves, F2101P - int 1250" (around $400 just in valves) with NEW valve guides installed. Fresh 3 angle Valve Job and spring install. The AFR heads had about 2 less cc's than the 990's so maybe a little of the et came from a slight increase in compression. dallas labor gigs Jul 26, 2011 · BBC BB Big Block Chevy 990 Heads ALL NEW. 550" correct? Can the spring pocket in the head accept larger diameter springs WITHOUT cutting? If so, on a set of 1969 cast iron heads, what is the largest diameter spring I can install without cutting the spring pocket? Anyone Running 077 BB Heads? Jump to Latest Follow 17K views 14 replies 6 participants last post by BBPanel May 17, 2005 B BBPanel Discussion starter 118 posts · Joined 2001 #1 · May 13, 2005 P 714 posts · Joined 2007 Get them cut for 288 valves and some port work done. These cylinder heads meet GM's stringent quality standards and provide excellent service and durability not found in used cylinder heads. Dec 27, 2002 · looking for information on flow numbr of stock 990 rect port heads (mine are just slighlty ported). 5 with no other changes. The 026 head is a LS6 rectangle head. According to the source I have 820 heads are 1971 402/454 oval port open chambered heads. Here's the build: 427 BBC, +. Use the big heads and very low compression ratio. Factory heads are classified as either high-performance (rectangular port) or standard passenger car (oval ports). 19 intake? The engine would be a 454 (not sure on over bore), 4135 rod and 120:1. My 1970 SS454 LS6 SuperCar certified stock appearing 11 A short review over porting 781 big block chevy heads for larger valves. What do you guys think, these will be a cheaper alternative to purchasing the $1300 Merlin Heads. Check out these illustrated Impala profiles, starting with the 1958 original.
250" (around $400 just in valves) with NEW valve guides installed. My experience leans to valve seat ression is directly linked to guide clearance. Chevrolet Performance service replacement cylinder heads are direct replacements on most 1990-and-later GM Big-Block 454-cubic-inch and 502-cubic-inch engines. Chevy Nova Forum 64K+ members. lucky men jeans Expert Advice On Improving Your Home. Fresh 3 angle Valve Job and spring install. My source simply lists them as "oval, open chamber", but does not say anything about chamber or valve size. Show Printable Version Click. In other words, it's a placebo effect -- if we think something is going to put us in the mood for love, we'll. Model specific subject matter experts, classified ads and more. i Can Also Change From 250 Valves If I. nct when he calls you annoying The AFR heads had about 2 less cc's than the 990's so maybe a little of the et came from a slight increase in compression. Open chamber BBC heads are usually abut 119cc. For some add'l numbers, change to a roller (retro-hyd or solid) and pick up another 30. The AFR heads had about 2 less cc's than the 990's so maybe a little of the et came from a slight increase in compression. It is a service replacement head, also used on Mark IV crate engines. The cylinder heads have rectangular intake. cheap land for sale near new jersey 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. The 396-402 heads are much smaller. Speed Pro says they should work with an open chamber configuration. AFR's 335cc BBC Enforcer cylinder heads feature their Permanent Mold "As-Cast" Technology surfaces on the intake runners, exhaust runners, and combustion chambers that allow for extremely accurate and repeatable port location/performance. Both are presently stock, no porting but have been cleaned and maged. Get this they are oval port and smaller valves cast on them. 5-1 is about as high as anyone wants to risk running. 1488 heads work well with our PCE349.
It was a crate gm engine, we put a roller cam and a dominator on it with a single stage fogger system and in a 3300lb Camaro and it would run 80's all day long0's without nitrous. 50% CNC Ported Combustion Chambers. Superior aftermarket oval-port heads are available from all major head suppliers in iron or aluminum. The larger port is better for higher rpm, such as racing. Functional with a wide variety of standard parts. I've had plenty of issues along the way but my 489 streeter is on it's way to being built. I have two BBC motors, a 454, 049 heads, Performer RPM, headers, and not sure of the build, pretty mild, in my new to me '72 El Camino the other on the stand, a 427T/496, 188 heads, being refreshed. Best Big Block Chevy ( BBC ) 781 Heads, Year:73-84 for sale at AlliedmotorParts. 100% CNC Ported Combustion Chambers. The announcement comes a day after India piled pressure on tech firms. Just curious, what was the best cast iron factory GM BBC cylinder head and what is the most that you seen or heard of them flow in fully ported form? just wondering where the 088 rectangle port head that has a 325cc intake runner with 288 valves stack up against those aftermarket heads and even the 049's which i run on my 454 - soon to be replaced with the 088 heads. » Members from all over the US and the world! » Help from all over the world for your questions. It is a service replacement head, also used on Mark IV crate engines. The weight loss depends on which castings you have and which your switching to. Here's a build you all can "kick" around for a while. bodyguard jobs Says they are rare 425 HP head. Nov 30, 2001 · C3 Tech/Performance - Opinions On Big Block 990 Heads - I'm thinking about getting a set of #6272990 Rectangular Port Heads w/ 288 Valves. Cylinder Head, Performer RPM, Aluminum, Bare, 118cc Chamber, 315cc Intake Runner, Chevy, Big Block, Each4L/454 Chevy big block Gen VI Cylinder Heads and get Free Shipping on Orders Over $109 at Summit Racing! Find many great new & used options and get the best deals for Chevy Bbc 990 Cylinder Heads at the best online prices at eBay! Free shipping for many products! Sep 16, 2006 · It ran 575 @ 116 mph in the 1/8 mile consistently. The 026 head is a LS6 rectangle head. The larger port is better for higher rpm, such as racing. Mar 10, 2021 · Looking through the GM catalog from 1989 it says Part Number 14096188 with a casting number of 6272990. Estimated to ship direct from manufacturer on 11/04/24, pending manufacturer availability FREE Shipping. Get ratings and reviews for the top 11 gutter guard companies in Chevy Chase, MD. Chevy Big Block Cylinder Head Codes (ALL) Casting No CID Exhaust CC. Model specific subject matter experts, classified ads and more. Get ratings and reviews for the top 11 gutter guard companies in Chevy Chase, MD. 94 Fire-Bird 540 BBC Convectional head Twin 91's stock suspension 3600lbs 748@169MPH Thank You to Mike Moran Mark Micke Joe Brown Pro Filer Reher Morrison Wilson Manifolds Precision Turbo and Injectors 030 over 12. I ran Dart 325cc heads on my 509 and they were a little small on my 540. Nov 29, 2006 · For Sale: Rectangular Port Big Block Chevy Heads BRAND NEW springs good for Titanium retainers and 10deg locks. 5 with no other changes. - This type of small-block Chevy heads is used from idling speed to 5,500 rpm for factory replacement, street/strip performance, and towing upgrades Fits engines ranging from 305 to 383 cubic inches. Standard port location versions available as well as the super raised. Head Combo, Intake, Head and Intake Bolts, Valve Covers with Studs and Nuts, Gaskets, Spark Plugs, Kit. Have a new set … I am a huge fan of the old 990 heads. The Ebay item number for the heads is: 160024789088 Rick. east craigslist It is a service replacement head, also used on Mark IV crate engines. 040, 781 heads with large valves, 10-1 CR, 60204 Voodoo cam, Performer RPM intake, 770 SA Holley carb, 3000 stall, 4. Use rec port intake gaskets. Cylinder Head, Performer RPM, Aluminum, Bare, 118cc Chamber, 315cc Intake Runner, Chevy, Big Block, Each4L/454 Chevy big block Gen VI Cylinder Heads and get Free Shipping on Orders Over $109 at Summit Racing! Find many great new & used options and get the best deals for Chevy Bbc 990 Cylinder Heads at the best online prices at eBay! Free shipping for many products! Sep 16, 2006 · It ran 575 @ 116 mph in the 1/8 mile consistently. The cast-iron Merlin series from World Products has been one of the most popular heads for retrofit service on all big-blocks up to and including 496-, 502-, and 540-ci displacements. 0L/427 Chevy big block Mark IV Cylinder Heads and get Free Shipping on Orders Over $109 at Summit Racing! More Power in Every Purchase - Join the Summit Rewards Program Today!. BBC Heads 188/990 NICE. The Brodix Small Block Chevy -18X Series Aluminum Cylinder Heads offer the best of both worlds, 18-degree horsepower without using expensive shaft rockers or offset lifters. best and easiest way is to 1. 73 454 2 bolt that will be bored 30 overM. Open-chamber designs are larger and provide lower compression. 0 346 83% 82%. Come join the discussion about performance, builds, restoration, modifications, classifieds, troubleshooting, reviews, and more! Show Less. Little-bitty valved, hard to find, 194"/1. Yours were cast on October 6th, 1974 and were used in the 1975 full size or Corvette06 intake and 1. For everyday driving/drag racing the NGK 5s are probably too hot for 12+:1 CR. I don't know what changed when t hey tacked on the 9, but here is what they list for those heads: 315cc intake port Chevy made these type of oval port heads for BBC engines through the years.