1970 GS 350-4, Level 2 Bowtie 200-4r, 10 bolt 8.2 posi 3.64 gear. All suspension upgrades to tubular components, UMI adjustable upper trailing arms, F41 69 Chevelle springs in front, 81 estate wagon springs in back. Front disc brake conversion. With no budget in mind and no turbo, I'd really like to get all the sbb has to offer without sacrificing streetability. I once planned on building a 350 on a budget but scrapped that notion. I would end up not being satisfied. Knowing full well I had stopped short of it's upper level potential. I've only built one motor in my life and it was 20 years ago. The motor is still in my car today and runs great but it's time to quench my thirst for more! This project must not force me to do away with the stock ram air system. I'll be using a 68 350 block, crank and heads, never milled, bored or ported, all factory specs. Stripped down to original castings. Unless a 70 block and heads falls from the sky that's what I have to work with. I'm dead set on a roller motor. Any suggestions on where I go from here?
Well the ultimate Hi power streetable car will be a turbo motor. But with N/a It's all about Head porting with a mild cam Stroking to 3.95 will also help squeeze out every ounce of power can purchase rods on ebay with 1.889 bearing for less the reconditioned sbb350 rods
Start with the short block, and then hopefully the alum heads will be out by the time you get the short block done. Or if you want to stay with the iron heads then jsut spend good money on oversized valves and really well done porting. The roller cam will be the key to making lots of power and staying streetable. I would consider a TB EFI system for better street manners, plus they normally sit a lot lower than a carb would and if the single plane intake comes out it will be tight for clearance under the hood. If you setup the shortblock with some nice pistons that are flat tops with valve reliefs then you can easily hit 10.5:1 compression, and with a mild roller camshaft that is custom made would make for a killer combo. I suggest the tried and true Eagle rod and Ross piston combo. You could order up the pisotns and rods: Engine builder Brian Leibee used an off the shelf Eagle rod at 6.30 long and had Ross make custom pistons for the application, after slight machining this combo has been track proven reliable and the cheepest option so far for forged piston and rods combo:The rod used for the Buick 350 is the CRS6300SLW http://autoplicity.com/products/1641313-eagle_crs6300slw_esp_6_300in_2_00in_lw.aspx Just spoke to Troys Engine builder Brian Leibee and he said that it would be no problem to do another setup like this for someone. The rods are VERY slightly narrowed, bearing tang moved and stock buick 350 bearings are used, the piston is custom made anyways so no problem to go with the SBC pin diameter. The piston builder Ross Racing Pistons. Job card # off the order sheet was 115793. Should help speed the process of ordering. Waited about 5 weeks. Pistons are a true flat top with 4 cc valve reliefs. Engine builder Brian Leibee with Leibee Precision Machine, Phone# 307-362-5049. Tell him Troy sent ya he will take care of ya.
Port heads with big valve or wait for TA aluminum heads And intake. Big roller with 10 to 1 pistons with block decked to blueprint spec.msd distibuter.1 3/4 headers.you could go with the 1.889 bearing rods and stroke motor might try for .110 on stroke with .060 or.075 over bore for more cubes.or if you are into E85 go to 12 to 1 compression.
Once you add the bearings it works with a 2" pin on crank. These have been used for about 8 years now by Troy, shifting at 6500 and running 12s. The rods are slightly narrowed, and having Troy's shop do the rod mods and order the pistons means a person could just make one phone call and then the rods and pistons would be sent to them once they were ready. Then take them to the local shop that is building the engine, have the engine built and your done. No offset grinding or special work needed.
Good catch guys... I would buy them through Brian anyways as he gets them for low cost and he knows exatly what work to do. Here is a good link: http://autoplicity.com/products/1641313-eagle_crs6300slw_esp_6_300in_2_00in_lw.aspx
Well you don't need custom rods if you go the route I suggested, they just need a little bit of machine work to make it work. For the pistons the ones I suggest are the only flat tops that I know of that are already designed and proven to work. All you would have to do is call Brian and he would set you up. He said they took a while to come in, but he could do the rods while he was waiting for the pistons. For the bore you can only really tell when you get the results back from the sonic test. Or if you want just skip the sonic test and go with a 30 thou overbore and you will be fine... If you wanted a large overbore and the sonic test came back good then you may be able to go 60 or 70 over, however keep in mind that future rebuilds might not be possible with a large overbore.
With the longer stroke rod and the custom piston combo, should my goal be a zero deck? How much would this combo sit in the hole? 20 thou should be a proper amount shaved to blue print the block correctly. Isn't this right?
If you are talking about using the rod and pistons combo above with the 6.300 rod and Ross pistons then what I would suggest is this: The shorter rod does not effect the stroke of the engine, it just means you need a taller piston compression height. I would have a shop measure your block's deck height, square if off so that all 4 corners are the same height, and then have the Ross pistons compression height made so that no milling is needed to get zero deck. This is the great thing about custom pistons, you can get the compression you want without milling the block and messing up the intake fit. And the best part is that you save money on the rods as they are off the shelf parts. Ross aalready have the pistons designed and it is no problem for them to adjust the compression height on the piston to get a zero deck on the piston. When people talk about cutting the block to the "blueprint height" they are saying deck the block to get it to 10.18" deck height which may take just a tiny bit or maybe more depending on the block as they are not all the same height. In this case I would not even worry about getting it to 10.18 I would just cut as much as it takes to get the deck of the block sqaure.
Need to have deck measured to see what you need to have shaved from top of block. It depends on your compression needs if you should zero deck.flat tops at zero deck will be 11 or higher. But with 6.300 rods you will need taller piston height to make up for shorter rod.decide on compression and rod piston combo ..085 shorter rod add .050 for stroke and say a 1.850 comp height piston a guess would be piston down hole in range of .050 to .070 but you need to measure to confirm.
I agree, that is a good example of the math, however like I said Ross will make any compression height you want so it is not an issue to get the compression ratio you want and no need to deck the block other than to square it off.
I have counted my numbers a few times with Derek on our build. Just got slowed on rods that where too narrow on big end. But found a set @ 6.350 with .827 pin since we have to go custom on piston pin size is no big deal as Sean mentioned. So we can just square block and adjust piston to meet what block height is.
Until the short block gets built. I don't have to choose cam heads and fuel delivery. I have a carb Ken @ EP put together for me using a TA 288 to calibrate but it may need some adjustment with a roller cam. It has all the correct stuff on it to accommodate the 200 R4 and the TA aluminum intake's lack of a divorced choke. I lean more toward a NA system because I've already met that expense. I'm positive this short block will take a year at least to get done unless I hit the lottery. I know where to send the iron heads but if Ken Betts gets the aluminum heads done before the short block is built and I have time to save my pennies. I'll cross that bridge when the time comes. I would imagine the oversized intake valves, seals, springs, roller rockers, bearings, rings, cam bearings, adjustable push rods, head bolts and lifters wouldn't matter which ever heads are used. The cam on the other hand. Would it be wise to wait to buy that until all the other details are decided on?
Wait to order the cam when you know how well your heads flow. If you have flow numbers for the heads then an optimum cam can be designed to work well with the static compression ratio and other factors. I would focus on getting the short block together.
My opinion is to drill out sump passage at least to 1/2 in and round off corners (supposedly can be drilled to 9/16) and drill out oil passages in oil pump housing. some ssy you don't need to but I feel it will lighten load on distributer gears and front cam bearing with more oil volume for hi rpms. The v6 has 5/8 on later blocks.also get a 5/8 pickup tube instead of the 3/8 that came stock. There are oil passages from block to head to oil rockers on 68-69 engines.you might want to plug those depending on rockers/heads you will be using.
Everybody wants to stroke the 350 MORE....WHY? Are you guys needing a diesel engine for torque, then you should buy one. I just don't understand it. Once you get beyond the torque, you need h/p and a free running engine. ????????????????
