Michael Tomaszewski's 350 Buick Engine Build Engine: Cast Iron 350 Buick, '68-'70* with oil modifications Bore: 3.840 Stroke: 3.850 Bore/Stroke Ratio: 1.002 Displacement: 356.70 ci Cylinder Vol: 730.8cc Chamber Vol: 57.5cc Deck Vol: 4.0cc Gasket Vol: 7.9cc Dish Vol: 11cc Total Chamber Vol: 81.3cc Compression Ratio: 9.99:1 Piston Type: .040 custom lightweight JE Pistons, notched Valve Notch Depth: .160 Compression Distance: 1.890 Skirt Clearance: .0045 Piston Weight: Deck Height: 10.211 Piston to Deck: .021 Ring Land Diameter: 3.803 Piston Deck to To Ring: .250 Gasket Bore & Thickness: 3.89 / .045 Pin Length & Diameter: 2.500 / .940 Connecting Rod: Stock Cast Iron, Polished and Lightened Rod Type: Cap Screw Rod Length: 6.375 Rod Weight: Before: 660 grams After: 613 grams Cylinder Heads: Cast Iron 350 Buick, '68-'70* Intake Valves: 1.92 Exhaust Valves: 1.55 - Intake Flow ---- Exhasut Flow .050 50.6cfm ___ .050 33.2cfm .100 83.2cfm ___ .100 55.8cfm .200 148.5cfm __ .200 104.7cfm .300 198.7cfm __ .300 134.1cfm .400 233.0cfm __ .400 149.7cfm .450 241.4cfm __ .450 151.3cfm .500 248.0cfm __ .500 151.3cfm .550 253.9cfm __ .550 152.0cfm .600 255.1cfm __ .600 --------- .650 259.9cfm __ .650 --------- Note: The intake ports have been further ported sine they were last flowed (the above numbers) and the exhaust ports haven't been ported at all yet, so the numbers will eventually be higher. Valve Covers: Red TA Performance 350 Cast Aluminum Rockers: TA Performance Aluminum 1.65 Ratio Camshaft: TA Performance 350 Hydraulic Roller Centerline: 113/113 Duration @ .050: 231/231 Duration @ .200: 151.4/151.4 Max Lobe Lift: .365 Gross Valve Lift: .602 Headers: TA Performance 2.5" Full Length Chrome Intake: TA Performance Aluminum Stage 1 350 Intake Manifold Carburetor: 750cfm Quadrajet Ignition: Stock Distributor w/Pertronix III Module & Coil Timing Cover: 350 Buick Timing Cover from TA Performance Water Pump: TA Performance High Performance 350 Miscellaneous: TA Performance Thermostat housing, all TA Performance bearings *Block and Head Dates are unknown so we guess between these years We have a software dyno that is surprisingly very very accurate from past engines that we calculated and were then dynoed, one that we know of was exact. I ran the program with the above parameters except with full exhaust, a clutch fan and 91 octane: RPM --- HP --- Trq 3000 __ 214 __ 374 3250 __ 233 __ 376 3500 __ 255 __ 382 3750 __ 292 __ 409 4000 __ 320 __ 421 4250 __ 345 __ 426 4500 __ 373 __ 435 4750 __ 393 __ 434 5000 __ 400 __ 421 5250 __ 410 __ 410 5500 __ 417 __ 398 5750 __ 417 __ 381 6000 __ 417 __ 364 6250 __ 410 __ 344 Bumping Compression to 10.5:1 Results in Peak HP/Trq: 423@5500rpm/441@4500rpm Now changing the Carb to a 950cfm: RPM --- HP --- Trq 3000 __ 213 __ 373 3250 __ 234 __ 378 3500 __ 258 __ 387 3750 __ 296 __ 415 4000 __ 329 __ 431 4250 __ 357 __ 441 4500 __ 386 __ 450 4750 __ 403 __ 446 5000 __ 412 __ 433 5250 __ 423 __ 423 5500 __ 430 __ 410 5750 __ 428 __ 391 6000 __ 426 __ 373 6250 __ 416 __ 350 Bumping Compression to 10.5:1 Results in Peak HP/Trq: 436@5500rpm/456@4500rpm Now with a Single Plane and a 750cfm RPM --- HP --- Trq 3000 __ 198 __ 346 3250 __ 217 __ 351 3500 __ 243 __ 364 3750 __ 282 __ 395 4000 __ 316 __ 415 4250 __ 347 __ 429 4500 __ 384 __ 448 4750 __ 409 __ 452 5000 __ 419 __ 440 5250 __ 432 __ 432 5500 __ 443 __ 423 5750 __ 445 __ 406 6000 __ 440 __ 385 6250 __ 430 __ 361 Bumping Compression to 10.5:1 Results in Peak HP/Trq: 452@5750rpm/457@4750 Now with a Single Plane and a 950cfm RPM --- HP --- Trq 3000 __ 196 __ 343 3250 __ 216 __ 348 3500 __ 242 __ 363 3750 __ 282 __ 395 4000 __ 320 __ 420 4250 __ 351 __ 434 4500 __ 390 __ 455 4750 __ 414 __ 458 5000 __ 424 __ 446 5250 __ 442 __ 442 5500 __ 450 __ 430 5750 __ 453 __ 414 6000 __ 451 __ 395 6250 __ 440 __ 370 Bumping Compression to 10.5:1 Results in Peak HP/Trq: 460@5750rpm/463@4750 As for the whole increasing carb cfm and the power numbers jumping, I dont know what to think of it because I can make it 1200cfm and the numbers still climb. Not too shabby for a little 350 that still has a little bit more potential in it :beers2:
Sounds great! OK, so I need a bit of schooling on "Polished and Highly Lightened Stock Capscrew Connecting Rods". Can someone describe the process and benefits?
Hey Mike, great sounding build. Alot of guys will be following this with great interest! Keep representing the 350! :beers2:
Yes, I dont have numbers atm but I'll add them to my first post. 1.92 intake and 1.55 exhaust We ground a lot of material off around the small pin end and took a lot off of the caps, by doing so this decreases the weight of the rod and thus equates to a lighter rotating assembly which should help make a little more power, less weight the engine has to move to rev. Once we did that I polished the sides of the beams, oil runs off of them better and it reduces any stress risers or removes any microscopic cracks to "strengthen" the rods (not really but materially it technically does). That and they look really pretty too :Brow: Engine isn't built yet, heads still aren't done but I can take and post pictures of everything before the build starts too.
Now IF you were actually testing aluminum heads & SP-350 on the dyno, you would have great interest.:Brow:
Sound great! Now just to keep this all in perspective, what kind of money would we looking at to have this done to our motors? Thanks Matt
Super Mike! Thats exactly the type of build I would like to do. I was hoping for ~375 hp & torque. If I can get over 400 that would be great! You should be done about the time I'm ready to start, I'll fallow this with interest. I'm sure there are a lot of us that can afford to do a build like this but wouldn't even consider spending money on aluminum heads even if they were available.
If you need another platform to experiment/fine tune your build please tell me. I can have the car on a transport in about 30 minutes.
Hey Mike, quick question on the rockers... what lift would you start to worry about clearance with a 10:1 piston without valve reliefs? I've been eyeing up a set for myself.