i have a 327 sbc. i was using water late last year. my first thoughts were a head gasket or intake. i did a compression test and all seemed fine. i had 150 pounds on all eight. i also had a miss that would come and go. the usual plugs and wires etc were replaced. the miss was still there. i figured i would tear it down this winter. i got the heads off and had them pressure checked. all 8 exhausts are cracked and one intake. the shop says this was common on the old fueley heads to crack above the seats. so i need new heads. I'm a mopar guy not a chevy guy. i bought this 66 chevelle 30 years ago in high school and now it needs some attention. it had double hump date coded heads and intake on it. I'm looking for more hp. the machine shop says renegade aluminum heads and a rpm air gap intake will get the most bang for the buck. it would go on the 327 block with a 6 inch h-beam rod. hot solid lift cam 750 double pumper,headers, msd-6 ign. and its a four speed with 4:11 gears. i drive it on the street a lot and want to run it at the track a few times. what are your thoughts.
Usually you don't see those heads crack like that,but it's irrelevant now.... Combo sounds solid,and will perform.... Just the 6'' rod deal- exisisting already,or planned? If planned- why a 6,and not a beefed stocker? aftermarket is cheap concidering machining and all......Scat,Eagle,Summit......What do you have already?
I have heard the renegade heads have problems with the exhaust seats. I know it's not cheap, but if you're going the aluminum head route, I would just suck it up and go with a more reputable brand. (AFR, Brodix, Dart...) That said, I'm sure that 327 will be potent with modern heads that flow well. What compression ratio are you planning on running?
i put in the 6 inch rods last year on the shop owners advice. they do a lot of sbc race engines. he said the engine would make more torque. it has the stock small journal crank in it. rods are eagle h-beams. the pistons are the keith black silvolight I'm not sure that is the correct spelling. the shop said i will have 10:1 compression. i know the alum head will wick more heat and be less prone to detonation.
Are you still working with the shop that originally did the heads? Did they put the seats in? I willing to bet they cut too deep when they did the original job an the heads cracked when they pushed the seats in.....ask me how I know...
no its not that. i bought these heads at carlisle a few years ago. my original intention was to return the car to a l-79 365hp setup. the car is one of these l-79 cars. so i started to collect all the special parts. the engine that was in it when i bought it in high school was a 350. the l-79 engine for 66 used a unique block and heads that were only made from jan.66-june66. they also used all the other parts like the finned large balancer the large alternator deep groove pulley, larger exhaust manifolds etc. so i bought up all this stuff and the heads were already machined. i just put on springs and valves. i have done a lot of business with this shop over the years and trust them. I'm just looking for others opinions on the heads they recommended. I'm just looking for the best option with out breaking the bank.
You are correct closed chamber GM heads usually crack between the valve and the spark plug hole. That does not change the current problem though. I run trick flow heads and like them real well, they are a good street strip head and not especially expensive. I do not care for the edelbrock performer series intakes. Yes they are hyped and yes they are over rated just like their cam shafts. You can do just as well if not better with stock GM parts and a little elbow grease. I do like their heads, they make a pretty damned good head. If I wanted to stay with a stock appearing head I would find a pair of 327 Turbo fire (power pack?) heads and pocket port them and run 'em. But that is just me I suppose , and good castings are getting hard to come by these days (hence the trick flows I am currently running ). They will give you more then enough performance to run hard on the street and race once in a while.
Hey Racer I know this does not address your original reason for this post; but you said your Chevelle was a 66 correct, and you stated you wanted to return it to it's l79/365 hp configuration. I know you are a Mopar guy, but I just wanted to let the guys that maybe don't know the finer points of GM small block history know that their was no l79 offered in the 66 Chevelles. Both 1965(350 hp) and 67(325 hp) were available with the l79 engine. The 66 Nova did use this engine rated at 350 hp though, as well as 67 Nova with a 325 hp rating(only 6 or 7 were built) These were all the same 11.25-1 comp. as well as same cam/valvetrain configuration. I could spout off a lot more trivia here and I'm not not trying to sound like those uppity numbers matching guys, but there is a lot of misinformation on the web about these cars. Good luck on your mission. Doug p.s. I also highly recommend Air Flow Research for aluminum heads.
I have only owned one brand of aftermarket head, Brodix. They have been flawless. There are probably others that are just as good. But I would buy these again in a heartbeat.
You might check out the GM Vortec heads from GM Performance. Not Aluminum but the 220CC runners and, big valves and heart shaped chambers make real power. I bought a set for a 400SBC ready to bolt on for around $325 with 170CC intake runners and they will flow more air than the engine can pump up till the cam signs off.
I have run Dart, AFR, Procomp aluminum heads. All worked well. There are several new heads out. Promax is one getting good reviews. I currently have a new set of Profilers on order. They are getting rave reviews. Cast and machined in Ohio. They will outflow my Darts by quite a bit. Paint'em chevy orange. Nobody will know.
[QUOTE="jaw22w, post: 10890694, member: 213900" Paint'em chevy orange. Nobody will know.[/QUOTE] Only the guy with the Ford you just dusted.
ddddenny the factory never published they offered a l-79 chevelle for 66. but they did make some starting in january. I have met some original owners. the chevy book on casting and part numbers lists the special parts they used. the book even goes so far as to distinguish the part numbers between nova and chevelle. a example would be the exhaust manifolds. the stock 327 took a 2 inch pipe the l-79 took a 2 1/16. due to the different bodies there are two different castings. i have a set and could send you a pic. i could pm you the info on the parts with casting numbers if you would like. i brought the car to the national chevelle owners meet a few years ago. several other owners of 66s were shocked to see it. thats were i found out the car was special. up until then i thought it was just another malibu. when i was in hs nobody cared about numbers matching. my plans have changed since i put this engine in I'm now going for more durability and power.
i may have found a set of holley heads. they were offered in a cam,head,intake kit called systemax a few years back. anyone have any experience with this kit. they claimed 425-450 hp. thanks to all that have responded.
I'd just go another set of camel humps, nothing ruins the traditional underhood look like a set of accessory bolt heads. Camel humps are still plentiful, around here they have rebuild pairs at the swap meets for around $500. I looked into the 6" rods on the 327 for my daily, and I'm going 10.5 to 1's, the biggest thing that sold me was the pistons being around 500g instead of 600g so all in all including the rod weights I saved 85g off each cylinder's up and down weight. That's a whole lot of mass that isn't being forced up and forced down every rotation
6" rods making more torque is a bunch of malarkey to me, but I'd use 'em just for the fact that they will stabilize the piston in the bore better than a shorter rod. Read what Iskenderian has to say about rod lengths in his Tech Tips 2005.... http://www.iskycams.com/techtips.php#2005 If you're going to use a longer rod, you might just as well use one that makes sense. If you use a 5.850" rod, such as the Eagle CRS5850S3D shown here..... http://www.motorsportsunlimited.com...sp-connecting-rods-small-2-000-crank-journal/ then you can use any off-the-shelf 350 piston (1.560"/1.561" compression height). With a crank radius of 1.625", rod length of 5.850" and piston compression height of 1.561" (Keith Black KB105-030), the stack measures to 9.036". Cut the block deck height to 9.020" to make sure the decks are square and each corner of the block is the same distance from the crank centerline so that every cylinder has the same compression ratio and the same squish. With a block deck height of 9.020" and a stack of 9.036", the pistons will pop up out of the block by 0.016" with the piston at top dead center. Use a Fel-Pro #1044 composition gasket (0.051" compressed thickness) to set the squish at 0.035". Use Pro-Filer aluminum heads, 23 degree, 180cc intake runners and 70cc chambers. Makes 10.276:1 static compression ratio with 0.035" squish. http://www.profilerperformance.com/racing/cylinderheads/sbc-23-degree Pay attention to the KB Piston instructions for piston to wall clearance and ring gap . Their pistons fit tight in the bore and need more ring gap than some other piston manufacturers. https://www.uempistons.com/index.php?main_page=product_piston_info&cPath=3_4_22&products_id=466 Use the Air Gap intake only if you will use the motor mostly at the track. If you will use it mostly on the street, then use the Performer RPM model, part number 7101. Street motors need the heat of the motor running through the intake manifold to help atomize the air/fuel mixture on its way to the heads, so the Air Gap model may present some driveability problems on chilly days. For your info, aluminum heads heat and cool at a different rate than the iron block they're bolted to, so you need a composition gasket to help absorb some of the movement and prevent fretting of the aluminum heads. These 0.051" gaskets will do that job nicely. I see that some fellows use steel shim gaskets with aluminum heads. Not a good idea. Use a retro-fit hydraulic roller cam such as Howards #CL110885-08 installed straight up, a good quality 10", 2500 stall converter, some 3.73-3.90 gears in the rear and hang on tight. This combo should easily make 425hp and 450ft/lbs of torque using a 750 carb and 1 5/8" long tube headers. 110885-08 is the cam only. CL110885-08 is the cam and lifters. You should be able to find the kit for under 600 bucks. Use these tutorials to help do this whole mess properly..... http://www.crankshaftcoalition.com/wiki/Valve_adjustment_SBC/BBC http://www.crankshaftcoalition.com/wiki/Determining_top_dead_center Here are 19 reasons not to use a flat tappet cam...... http://www.crankshaftcoalition.com/wiki/Camshaft_install_tips_and_tricks .
hey racer, you are correct about your rare L79 chevelle. that engine was available in 66 in all body styles including the 300. too bad the original bullet is long gone. there are about a billion ways to build a small chevy. your bottom end is stout already, so slam those holley heads on w/ a gigantic two carb tunnel ram and call it good.
its funny you say to throw a tunnel ram on it. i did just that after i graduated hs. to be cool in 1984 you had to have some thing coming out of the hood. that was the hay day for the street machines. mine had the tunnel ram with a pair of 660 center squirters velocity stacks on top of that. it ran like crazy until the cylinders washed out. then gas went up to a dollar a gallon and it came off. i would park the car every night in front of the house. im still surprised nothing was ever stolen. i do have one pic from back in the day with the tunnel ram on the car. good memories indeed.
in a previous post i said the l-79 was available for the chevelle in january. i went back and looked at my resources and i was wrong. the casting for the engine started late in january and the cars were available in march. my car was made the third week of may-66. the blocks had thinner cylinders for some reason. these cars must have been built to race in some specific stocker class. almost the same hp as the 375 hp 396 yet less weight. who knows.
The '67 that we drove from Oregon to here in '71 was L-79 powered. bench seat, cloth upholstery, no radio, 4 speed, posi, steelies and dog dish hubcaps. You could still order cars back then if you knew what papers to fill out. That said I have had an ongoing love affair with the L-79 motor for a very long time. I think that everyone has something that they lean toward, the L-79 is mine.
I don't know if it's advice but a few years ago I had the strongest smallblock I ever had. It was a 74 'vette with a 383 and had AFR aluminum heads. Not sure what else was done to that engine but it had a helacious lumpy cam! Was a street car with a worked 400 turbo and ran 7.90s at the local 1/8th mile. Needless to say, I like AFR heads.
mine is a aztec bronze standard black interior bench seat four speed. the only option on the car is a rear window defroster. who orders a stripped malibu with only one option exept a racer from wisconsin that wants to see out of the rear window as it blows away the competition.
Honestly if your car is that rare I would put that motor stock and put it under the bench , nothing like windowing a valuable block... Then I would build big ... Or better yet buy a running hot motor off a guy upgrading for pennies on the dollar good prepped sbc 's should be relatively easy to find , dress it as stock as you can and go beat on it and don't worry
then i might as well sell the car and hang a picture of it on the shop wall then it will never get hurt by me. there are no sacred cows in my collection. we chop, alter, modify, race ,beat and drive everthing we have. they built the l-79 to go race and thats exactly what we will be doing. with the hemi coupe i dont have extra cash for another sbc. the smart thing to do would be to pull it but were do you stop. do i pull the fenders off or change frames so i dont hurt the originals
I had an original L-79 66 NOVA that was turned into a drag car long ago...... Parts were long gone.... I would say unless it's going for a 100 point resto- just build it the way you you want,and dress it accordingly. but,with the intake,and the 585cfm holley,it might not pan for the rest of things.... Do YOUR thing,and burn tire! Forget the #'s matching,or parts scrounging,just make yourself feel good about it,step down,get sideways,and leave some tracks......
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