Hi All, Not been on here for many years but it is getting close to making a start on building my Buick 350 motor. I would like to pull on the mountain of knowledge you guys have... The story goes:- Engine 1) I bought a 1980's V8 engine in bits many years ago, I made a start rebuilding it but the workshop I tasked with boring the block for my new pistons made an error and over bored the block so I was very annoyed and put the engine aside for me to calm down.... Engine 2) I found a siezed 350 for sale on Ebay, bought it and dragged it home. upon stripping it down I found it was an SP block GS motor, very very seized on 2 cylinders but the idea was to have it bored for the new pistons PROPERLY this time... but then Divorce hit me.... Engine 3) A random ebay sale was made aware to me for a Buick 350 crate motor, rude not to buy. this is a BRAND NEW short motor, block, crank and pistons... not recon but brand new so I bought this as it was cheaper than having a rebore done to the SP motor... So now I have loads of bits and need to know what to use to build the best motor I can. The heads all seem to have the same casting numbers and look the same so I do not know which to use. I will get exhaust manifolds made custom as this motor is going in a 1953 Buick Special. The intake, I have 2 cast ones and I am about to pick up a TA Performance stage 1 when I visit the USA next month for VLV. The Cam, I have the stock one, the SP one and I have a stage 1 performance one. Crank, I have the original one from Engine 1, reground, Engine 2 (SP) which is rough and the Engine 3 which is brand new. Distributor, I have used the SP one on my UK 3.5 litre rover engine so will need to get a replacement so thinking of a electronic ignition one although I could buy the electronic one for the 3.5Litre and swap it back. The overall requirement for this engine is to sound amazing and ideally I would like a good 300BHP + to 350BHP. Its going through a TH350 into the stock rear end from the 53 Buick which I will modify to open drive. Stock wheels to make it a sleeper. Comments gratefully received please... Spence (UK)
Good morning! I would attempt to use the Sp engine pistons, rods and crank in the new block. The crank is balanced to match the sp pistons and rods as the later engines have heavier rods. The late pistons give about 8:1 compression, the Sp code pistons will give 9.5:1 or better, which you will want to hit 350 Hp. I would use a HEI distributor and a Q jet from Ken at Everyday performance. He can set you up with a distributor and carb that are ready to use. edit, get us some pics and part numbers? Block numbers for the “new” engine? Pics of the pistons? Part number for the “stage 1 cam”? https://www.everyday-performance.com/
Hi Sean, I bought the original rebuild kit with performance CAM in 2007 and dont have any data or part numbers to hand as Divorce tends to take alot of paperwork etc... (just glad I kept all the important things). With the SP motor, we had to really "Persuade" the pistons out of the block with large hammers with wood so I was reluctant to re-use them but I have kept them so what I could do is check the sizes etc and clean them up to see if we damaged them in any way with the hammering... The engines are all away at the moment but when I get back from our holiday to the USA then I plan to get everything out and make a start on putting something together. If it means building up a runner with the new engine and rebuilding the SP to factory then I will do that. I will see if I can lay my hands on the SP pistons and measure them up against other ones I have here and see if the Rods have any part numbers on too. The SP engine actually came out of a Ford Capri but was removed to put a chevy in and they left the SP motor outside so water got in through the carb. such a shame they didnt know what they had. P.S. love your website, some nice things there.
Hi Sean, Ok, I couldn't wait so went to the shed of "Things" and dragged out the new pistons from the rebuild and the old SP pistons and yes, the SP pistons are about 1/16 taller so would give the better compression. The bad thing is, I just checked the SP pistons and 2 are cracked as expected as we had to use a lot of force to removed them. so now I wonder how to get hold of the higher compression pistons if they are available? My next challenge is to find the data on the CAM as that is now in the 1st engine. reluctant to remove it yet as I dont have cam bearings inside the "NEW" engine and would prefer to transplant it in one hit.
most of the good 10:1 pistons have been discontinued. I happen to have a set of vintage forged 10:1 pistons for sale: https://www.v8buick.com/index.php?threads/trw-forged-350-pistons-10-1.367369/
Use later cap screw rods is one of your engines has them. Stronger then 70 rods. Replace cam bearings, deck block can get more compression. I used the 70 sp distributor with a recurve kit and a Mallory electric conversion kit. SP cam may have best performance. All the cams you have sound like should produce good torque and not need to rev engine very high. I would suggest new valve springs. Oiling modifications to block with the bigger oil pump pickup tube. Melling 20IS5 I believe is part number. Drill out oil passage in block to 1/2 inch. Get the harmonic balancer rebuilt.
buy Sean's pistons but use the 73 rods, they are stronger they are cap screw. the only part that is good is the SP block for a numbers matching car after that it is up to you on parts, original or not. Drop some alums on it out of the box no porting needed on those you will go fast. lol
My trw forged pistons & the lighter early rods needed 1 slug of mallory on my last build. Seans trw pistons with heavier capscrew rods may need more than 1 slug for premium balancing. The trw slugs are heavier compared to stock slugs.... Just an fyi.
