Hey Jeff, it was great meeting with you and playing with your sbb 350 Wednesday! Mart and I made it over to lend a hand and a little bit of expertise getting Jeff 's sbb 350 engine ready to assemble. First we helped him remove the pistons and then the crank to get down to the bare block. Then we drilled the pick up hole to 17/32" and the long hole in the block to 1/2" to get a bit more volume out of the oil to the pump. After that we ball honed the cylinders for the brand new used very low mileage pistons that Mart brought over so Jeff's engine will have some drivable compression with a st300 go slow trans.(the 68 st300 is the NON-switch pitch) To help the trans a bit Mart hooked Jeff up with a 2,000 stall converter because the '68 st300 uses the same converter as a th350. Now instead of the '68 st300 only having around 1.2:1 torque multiplication it will now have around 2:1!(not to be confused with the stich pitch dual stall speed st300 prier to '68 that would give 2.45:1 torque multiplication in high stall) We spent about 6 hours there getting the block prepped, the cleaning of the block is Jeff 's home work. The cam he showed us that came out of the engine had a worn out lobe and the crank needs to be reground to .020"/.020" from .010"/.010" because of the metal from the worn out lobe running through the engine! Here is the side job I did for Dave yesterday, the guy wanted his stroker 4.0L Jeep straight 6 cylinder to have a little less compression so he wanted the dish taken a bit deeper; A piston vise, rotary table on a mill and I had the pistons altered in no time! To go from IIRC 15cc to 20cc I had to go about .030" and make the arc on the right of the right hand piston became an actual D-shaped dish like these are advertised. These are hypereutectic pistons so we needed to use carbide, with the silicone content in these wear out regular tool steel very fast, silicone is basically sand which is what glass is made of. The job turned out nice, I think the guy asking to have it done will be happy with the pistons. From what I heard about him is he is an engineering college student in a northern Michigan school where it gets very cold in the winter.(Dave told me the school but I forgot) Dave said that he is a sharp guy and compared him with me on how sure he is about how he wants things done.(Dave's words. "he's almost as bad as you")LOL Sounds like a sharp guy to me!!! Its been a busy couple of days, was good to get away of the sh!7 storm that is my life right now! Derek
Thanks Sean! When Jeff has his homework done and his crank is done and back with Jeff, I or we'll(me and Mart) be back to help him to assemble his engine, Mart might be to busy fishing to go there a 3rd time, but I would like to be there to help him get it started and the cam break-in done. Derek
Great that you guys could help out. Wish I could join the party. Just way too much going on right now.
Hey Jeff, if you want to go .030" on the mains I'll sell these to you. $30+shipping http://v8buick.com/index.php?threads/buick-350-main-bearings.322549/ I grabbed them because they were a good price, and I'm already planning my next 350 build. So I don't really need them.
I really admire you guys helping him out like that. Here's more info on the ST300 to clear up any confusion on the torque multiplication... This is not intended to start anything derogatory, but simply to correct the information. Taken from Wikipedia on the ST300: "From 1964-1967, Buick and Oldsmobile versions of this transmission used a torque converter with a variable-pitch stator called Switch-Pitch by Buick and Variable Vane by Olds. The stator blades moved from high to low position by an electrical solenoid and a stator valve, controlled by a switch on the throttle linkage. At light to medium throttle, the stator blades were at 32°, providing a torque multiplication of 1.8:1 and a converter stall speed of approximately 1800 rpm. At ⅔ to full throttle, the blades switched to the 51° high position, giving torque multiplication of 2.45:1 and a stall speed of approximately 2300 rpm. The blades were also set to the high position at idle to limit creep when stopped in Drive. The variable-pitch stator was eliminated after 1967. This feature was not used on the Pontiac versions of this transmission." ...and again from Wikipedia on non-switch pitch OEM torque converters: "The maximum amount of torque multiplication produced by a converter is highly dependent on the size and geometry of the turbine and stator blades, and is generated only when the converter is at or near the stall phase of operation. Typical stall torque multiplication ratios range from 1.8:1 to 2.5:1 for most automotive applications (although multi-element designs as used in the Buick Dynaflow and Chevrolet Turboglide could produce more)." The same single-stall converters on GM TH350 transmissions typically show between 2.2-2.5:1 torque multiplication (using small block engines) from various sources using OEM spec sheets. This is a pretty far cry from "1.2:1" ST300 and Chevy's powerglide were very similiar in componentry and geometry, and even used the same parts in some areas, with very similar parasitic loss because of it. I have more information on this than before, including cut-away views of either transmission showing the similarities, and a side-by-side comparison to the internals of a TH350, showing vastly less components on the 2 speeds. Ok, that's enough on that. I don't want this to derail the thread, so if anyone is interested on the details I just mentioned, PM me. Cheers guys!
If your crank only needs .020 cut then go with that. No reason to waste a possible rebuild/ cut later. Let the machine shop determine what needs to be done Mart and Derek are pretty good guys to give their time to help out some one on here to get their car set up right. Thumbs up to you guys.
Hello. I just want to give a huge shout out to both Marty and Derek for offering their time to get me straightened out. I'm totally amazed by their knowledge and pretty sure they've literally forgotten more about engines than I'll ever know. Thank you, thank you, thank you!!! Found a crank shop that I'm gonna take it to this week to have it ground to both Marty and Derek's recommendation. Will be ordering all the necessary parts as directed as well. Yesterday I ground down original casting burrs and such, scrubbed the block clean, cleaned out and wire brushed all the bolts holes and blew them out. Guys I would like you to be there for when it comes time to fire it back up so perhaps a third time indeed!!! Jeff
Great to here this kind of collaboration between Buick builders. And to echo others, the burning through money part is no joke. It always cost more than expected. Should be a fun little Buick 350 though. Good luck with it.
Since you have it apart I would get that valley pan set up that TA has to eliminate the valley pan gasket, then you can use the composites on the sides.
On that note...(burning up money) I know you are excited to get this rolling and drop off that crank to get ground but this will illustrate 'exactly' how budgets get blown out of whack and shops get blamed for bad work, parts are blamed for being junk, etc.... This is on the 600-625hp Small Olds I started machining this weekend, and it's a problem on the majority of off brand builds including so many even on this forum. Starting with a crank ground to "-.020" and a block "+.030", it will be cheaper to actually set those aside and start over. I still may reject the block after sonic testing. The short block fill will tighten up the bore appx .001", requiring rehoning. The bores were cut to reflect the minimum to achieve clearance on the forged piston, without the first shop actually measuring the pistons and......not considering that another 250hp requires a little more room to deal with the heat, which will require rehoning. Now that he needs main caps and possibly a girdle, I'll be boring caps/honing block as needed, which will.. change the final dimension of the main bores (variance with stock blocks anyways), which will... change the measurement on the installed bearings, which also vary on stock unmodified blocks and out of the box bearings. In effect, grinding the crank twice would be more than grinding more stroke, or using a steel crank. The rod recon cost towards a much lighter/stronger rod, allowing the stroke change. The cost of honing the block again added to the expensive Sealed Power pistons would have paid for a 200 gram lighter piston that could go another 1500 rpm higher with that better rod. Again, the same things happen on a stock build. Parts have a tolerance range, it changes with brand. It's best to clean and inspect things first, measure them up before you invest machining time. Then bring them back to the shop to machine, with whatever they ask you to bring.
Put a thin film of oil in those bores or you'll be cleaning some light rust out again. Lightly oil all dry metal. Cover with a large plastic garbage bag to keep it particle free.
Got the main and rod bearings in the mail yesterday. Just need a few more items, but luck has struck me a blow... an unfortunate but necessary auto repair on my daily driver has gobbled up my remaining Buick fund. Won't be able to have the car on the road by the time the dream cruise rolls around. It was a valiant effort by Marty, Derek and I to try and make it happen but life got in the way. That said, I do still plan on having it on the road by end of month or early September.
