I have a 1970 GS350 and It has been sitting for quite a few years and I want to compleatly rebuild the engine. I have a budget of around $3,000 to spend on the engine. I am wanting to build a street/strip car. What things would you recomend and how much HP do you think I would have in the end. thanks Adam
First, check the pistons, make sure they are in good shape, if so, you just saved $300+. 70 GS pistons are the best to go with if using stock pistons. Contact Jim Burek at pae enterprises to get all your stuff, he'll get you the right parts the first time. Things to get: Aluminum intake (Poston Or TA, same price, similar performance, many people will give you a different opinion, so personal preference reigns here). ~$250 new New camshaft. TA 212 seems to be a favorite. Also get new lifters and high performance valve springs. Get single or double grooved cam bearings. ~$50 (for a 350, single is perfect, no reasons not to go with double though) Adjustable pushrods are nice but not necessary. ~$??? New Water Pump, GMB NEW from Kragen seems good, ~$40 Check timing cover for wear (behind water pump, oil pump cavity). If wear is present, replace with a new one ~$90 Recommended is to use a thrust plate, this will save wear on the oil pump housing cover and help increase oil pressure. DO NOT use the high volume spacer w/ longer gears. New timing chain, double rollers are nice ~$50 Fel Pro full engine gasket set, - has everything you need except the valley pan gasket. $40 - $75 (depends on where you go, Jim B. had them for $40 a few weeks ago) New freeze plugs (brass!) and oil gallery plugs. (don't forget the 2 in each head) New main / rod bearings. Inspect the crank and turn if needed, make sure to get the right size bearings. Piston Rings - File fit are perfect, otherwise stock rings are ok. Headers, these will give a big increase in power. TA sells the best for the 350, poston and hooker also sell their own. ~$275 (then get a 2.5" mandrel bent exhaust from TA w/ dynomax mufflers) Then get an 800 cfm Q-jet and have it built to the specs of the rest of the engine. get a 2500 stall convertor for the trans. and put a shift kit in the trans. Thats about all I can think of, of course there is more... Should be less than $3k and get you around 300+ at the rear wheels... (350+ at crank) $.02 Dan
You do have the best of the 350 engines to start with. The 70 350 GS was advertised as having 10.25 compression and was rated at 315 horsepower. First, find a good machine shop in your area. Ask around, get someone who knows Buicks. There should be people on this list that can help. My opinion is go with a basic rebuild of the short block, paying close attention to the oiling system; upgrade the valve train (can check with PAE or TA Performance for recommendations), if the budget allows, some head work - bowl porting first. TA intake with an 800 cfm Q-jet is good, TA headers and the 2.5" exhaust with "X" pipe. TH350 trans with a shift kit on the 2nd setting, a (IMO) 2800 rpm converter, and a posi rear with 3.42 - 3.73 gearing. This is similiar to what I am working on right now. (More work on the heads; I have a friend with a cylinder head shop). I am shooting for solid 13 second times @ 100+ MPH. With the AC on. Hope to have it running in time for the Northeast GSCA meet at Cecil County in October. Chuck George 1970 Skylark Custom 1997 Regal GS
It's best to get the shortblock as bulletproof as possible! Definitely, find a 'Buick approved' shop to do the machine work and assembly!! If your local shop doesn't 'speak' Buick - run, don't walk!:Brow: Chevy clearances on our Buicks = a short lived engine!:af: Your best money spent for power is always in the heads...however, if the budget won't allow to fully port the heads, it can always wait until later! BTW, if this is the numbers matching engine - might be wise to pick up a different shortblock - keep yours in storage. If you do, get a 73 or newer one - the rods are the capscrew style, which are stronger (upgrade to the ARP bolts). *For the block, it would be a good idea to have it decked (.005"-.010" down). May need to be decked close to .050". This will give you the best quench for maximum turbulence - in addition to being better for power, it also minimizes the potential for detonation!:Smarty: *For the crank, after the block machining is done, have the shop install the bearings and torque the bolts down. Measure the clearance and have the crank turned (if necessary) accordingly. The crank grinder should have a good idea if it will clean up at .010" or .020". Make certain that he grinds the crank to give the right clearances!!! Looking for .0015"-.002"!! Same goes for the rods! *For the lifters, if you do have the block decked .040"-.050", use the Chevy lifters! They have the pushrod cup down .050" which works out just perfect for you! May not need adjustable pushrods that way. *For the heads, if you're trying to keep costs down, just a cleanup resurface job along with the valve job. If there's money for it, get the oversize TA stainless valves 1.920" intake and 1.550" exhaust. Make sure they 'bowl hog' under the 60* cut - open things up so that the 60* is about as wide as the 45* seat. If they don't do the bowl hogging - the heads might flow worse than they did with the small valves! *For the springs, match it up with the cam. I'd go with the TA 212 cam and the TA 1436 spring (use TA 1130 if you go wilder on the cam or will spin it higher). *For the intake, I don't think anything compares to the TA Stage 1 350 intake - BEST available! *Make sure your timing cover is usable! Scoring under the gears is BAD - replace if necessary! Also, make sure the cover to gear clearance is set properly. Might want to check on TA 1533 - high performance oil pump assembly - http://taperformance.com/pumpkits.htm - comes with timing cover and everything else already clearanced and assembled. I'm sure this isn't everythinig, but it should get you started.:grin:
Buick Parts?? Hey, let's not forget our FAVORITE Buick supplier...Mr. Jim Weise of Trishield Performance. I am rebuilding an engine and he is getting me everthing that I need at decent prices and he offers all the technical help that I need!:TU:
Thanks alot every one for all the info. I cant wait to get started. ill keep you posted on the project. adam
