ok im sure its been asked a million times but here it goes agian. i have a 57 chevy belair with a 455 buick, atomic efi,700r4,. the engine came from a 70 estate wagon i am going to rebuild it soon (runs fine 58k miles). are the heads on this engine all that great? i am looking at the eledbrock rpm's. would i gain a whole lot? would it be cost effective to keep my 70 heads? im not going for all out race just a nice cruiser and maybe some mpgs
I'd say those heads are great, should be the higher compression heads, might want to just rebuild it to stage 1 specifications, but first make sure the heads are actual 70 heads by looking up the casting numbers. Aluminum heads are nice and will save you good amount of weight and also have some benefits added to them depending on which one you go with. I believe the edelbrock ones allow you to use more readibly available Chevy parts, I'm sure others will chime in , but sounds like you have a nice set up there
Welcome aboard! I'm with Jose, the '70 heads are fine for what you're doing, I wouldn't even bother with the added cost of the larger Stage 1 valve conversion unless you were already planning some port work for a street/strip application. I'd just have them torn down and inspected in case some rebuild work is needed like a valve job, valves replaced, guides replaced, surfacing, new springs, seals, etc. If you have your heart set on the larger valves, check back here first since there's also some machine work that should be done to the combustion chambers that a lot of shops overlook when making the conversion. Devon
..and if you go to aluminum heads anyway, get the best made by TA Performance. But if what you have is running fine, do not tear it down unless you do intend to make a lot of changes to increase performance. A lot of change would be obtained from TA ported aluminum heads and a small roller cam. If you are willing to run headers consider stage 2 TA heads.
headers are out of question its really tight on the gear box now. not opposed to running a roller car but i must be a small one because i have a 2100 stall in my 700r4 trans and dont want another race car! i have 7 undrivable "race cars" it does run fine but i have 40k in the rest of car and the engine is the only thing left untouched. the engine is never been opened up from factory! runs great and strong "well it did in the wagon" now it has msd fuel injection, full msd ignition,and i want to make sure it holds up. all my other cars have aluminum heads and roller cams ect..
http://www.v8buick.com/showthread.p...ng-(Larry-s-motor)&highlight=Larry+roller+cam http://www.v8buick.com/showthread.p...te-and-Dyno-tested&highlight=larry+roller+cam
Here's a set of 455 shorty headers, http://www.v8buick.com/attachment.php?attachmentid=244800&d=1356105310
If you are rebuilding the heads and plan on racking up the miles definitely get hardened exhaust seats installed. From my direct experience my last 2 sets of cast iron heads only racked up 10,000 miles each before the seats receded and caused leakage. I'm starting to think the alcohol in the gas is causing more problems than no lead because I've run iron heads before with higher mileage and no problems.
well it looks great in the box. still getting all the parts i need for the build.the whole car is new(in boxes) except the engine. thats why i was thinking about a rebuild. it must drive betterray:. i will post as its gets going by this summer
Good luck with the build.If you stay with steel heads take NO LIFT'S advice.Alot of HP in what you do with buick heads.
I'm going to go against the grain here. I say do a quality inspection of the heads, exhaust seats probably wouldn't be a bad idea, but if you've been driving it and the seats look good, I'd let the machinist decide if new seats are required. I'd get a small "all torque" cam from TA, standard flat tappet with low spring pressures and run with it. Might only make 350Hp, but the torque will make it a nice cruiser and get good mpg. Big dollars don't have to be spent on modest goals IMO. If anything, deck the block a little to get the compression up to 9.0-9.3'ish and call it good.
TSB, you must have missed the part where he said it is a '70 motor. I'm going to go one step further and say I wouldn't even pull the engine apart if you are only going to do a mild rebuild. If you want a nice cruiser I'd just do a HOT oil pressure check on the engine first and then a compression check. If everything checks out decent just slip a mild cam in it and an Edelbrock intake if you don't have one now. Done. It is a shame to pull a low mileage '70 apart for a small performance gain because you just can't find original engines that don't need rebuilding like you used to. Even before you do anything get yourself a white "Stage 1" oil pressure spring. That will bump oil pressure up to 60 psi from the stock in '70 40 psi. Don't try to run thin Chevy oil. 10-30 or better 10-40 for spirited driving. If you get it rebuilt make sure the machine shop is familiar with the BBB's oil system shortcomings. No BBC bearing clearances allowed! Search it out on one of the many threads discussing it. Not much has to be done for a mild rebuild as far as the oiling system is concerned.