DynoSim combinations
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I have checked the results I get against real dyno pulls and this DynoSim has shown to be within 2% of real. Not bad in my opinion. I'm seriously considering upgrading to DynoSim5 and an add-on cam file. I have 800 cam files now, but the add-on would give me 6000 files. I was dragged kicking and screaming into the computer age, but I'll tell you, there's nothing any more fun than dinkin' on this thing. Well.....there was that time in New Orleans, but that's a whole 'nuther story... | I have checked the results I get against real dyno pulls and this DynoSim has shown to be within 2% of real. Not bad in my opinion. I'm seriously considering upgrading to DynoSim5 and an add-on cam file. I have 800 cam files now, but the add-on would give me 6000 files. I was dragged kicking and screaming into the computer age, but I'll tell you, there's nothing any more fun than dinkin' on this thing. Well.....there was that time in New Orleans, but that's a whole 'nuther story... | ||
| − | ===355 | + | ===355 SBC street motor, budget build=== |
*Block: '68-'86 Chevy 350 Gen I bored +0.030". Check main bearing bore for round and parallel, align-hone or align-bore, as *necessary to line up the bores and insure they are ROUND. Once the mains are valid, register the block on the main saddle and cut *the block decks to square the block up and set the squish where you want it. I don't want to hear any carpin' about the cost of *cuttin' on the block. If you can't afford to do this stuff, take up another hobby. | *Block: '68-'86 Chevy 350 Gen I bored +0.030". Check main bearing bore for round and parallel, align-hone or align-bore, as *necessary to line up the bores and insure they are ROUND. Once the mains are valid, register the block on the main saddle and cut *the block decks to square the block up and set the squish where you want it. I don't want to hear any carpin' about the cost of *cuttin' on the block. If you can't afford to do this stuff, take up another hobby. | ||
*Crank: Stock 350, 3.48" stroke, 2.450" main journal diameter. | *Crank: Stock 350, 3.48" stroke, 2.450" main journal diameter. | ||
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Stock converter and stock rear gear will work, but would be more fun with a converter that stalls at 2000 to 2200 rpm and a 3.73 rear gear. | Stock converter and stock rear gear will work, but would be more fun with a converter that stalls at 2000 to 2200 rpm and a 3.73 rear gear. | ||
| − | ===383 | + | ===383 SBC stroker 485 hp/496 ft-lbs torque=== |
Staying with RHS, using the Pro Action 180cc heads and reducing the advertised flow by 5% to get closer to real world results, the flow used for this build on a 383 will be as follows: | Staying with RHS, using the Pro Action 180cc heads and reducing the advertised flow by 5% to get closer to real world results, the flow used for this build on a 383 will be as follows: | ||
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*6000 481 421 | *6000 481 421 | ||
| − | ===383 | + | ===383 SBC stoker 505 hp/500 ft-lbs torque=== |
Same motor as above with [http://www.compcams.com/Cam_Specs/CamDetails.aspx?csid=238&sb=0 Comp Cams solid lifter flat tappet cam], 1.5 rockers. | Same motor as above with [http://www.compcams.com/Cam_Specs/CamDetails.aspx?csid=238&sb=0 Comp Cams solid lifter flat tappet cam], 1.5 rockers. | ||
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*6500 481 389 | *6500 481 389 | ||
| − | === | + | ===350 SBC L31 heads=== |
Flat tappet hydraulic cam, stock rail rockers, some head work for better springs. | Flat tappet hydraulic cam, stock rail rockers, some head work for better springs. | ||
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**Peak BMEP 184.5 @4000 | **Peak BMEP 184.5 @4000 | ||
| − | ===350 | + | ===350 SBC dual four barrels=== |
* Pistons: flat-top, 7cc's, 1.561" CH [http://www.kb-silvolite.com/kb_car/...php?action=comp p/n KB106-030] | * Pistons: flat-top, 7cc's, 1.561" CH [http://www.kb-silvolite.com/kb_car/...php?action=comp p/n KB106-030] | ||
*Heads: [http://www.summitracing.com/parts/EDL-5073/ Edelbrock E-Street] p/n 5073, 185cc intake runners, 70cc chambers, 9.53:1 SCR. Published flow was factored by 0.95 for this exercise. | *Heads: [http://www.summitracing.com/parts/EDL-5073/ Edelbrock E-Street] p/n 5073, 185cc intake runners, 70cc chambers, 9.53:1 SCR. Published flow was factored by 0.95 for this exercise. | ||
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**This motor should be waaaaaay fun with a 4-speed or auto with a loose converter. | **This motor should be waaaaaay fun with a 4-speed or auto with a loose converter. | ||
| − | ===400 SBC street/strip truck motor | + | ===400 SBC street/strip truck motor=== |
*400 block bored 0.030" and zero decked to the piston crowns, align honed main bearing bore. | *400 block bored 0.030" and zero decked to the piston crowns, align honed main bearing bore. | ||
*Scat [http://www.race-mart.com/Scat_Manuf...-3750-5700.html p/n 9-400-3750-5700] cast steel Pro Comp crankshaft. | *Scat [http://www.race-mart.com/Scat_Manuf...-3750-5700.html p/n 9-400-3750-5700] cast steel Pro Comp crankshaft. | ||
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Use a composition gasket that compresses to 0.039" to 0.041". With the zero deck of the block, this will put the piston crown at 0.039" to 0.041" from the underside of the cylinder head with the piston at TDC. This establishes your "squish" dimension at 0.039" to 0.041", which will optimize the motor for detonation-free operation on pump gas. | Use a composition gasket that compresses to 0.039" to 0.041". With the zero deck of the block, this will put the piston crown at 0.039" to 0.041" from the underside of the cylinder head with the piston at TDC. This establishes your "squish" dimension at 0.039" to 0.041", which will optimize the motor for detonation-free operation on pump gas. | ||
| − | === | + | ===SBC pump gas street cruiser=== |
*375-400 horsepower, 425+ lbs/ft of torque with 9.0:1 static compression ratio. | *375-400 horsepower, 425+ lbs/ft of torque with 9.0:1 static compression ratio. | ||
*Stock converter | *Stock converter | ||
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===400 SBC with Vortec heads=== | ===400 SBC with Vortec heads=== | ||
| − | This combo is best at building a lot of torque in the 3,500 rpm range. L31 heads on a 406 will not lend themselves to top end hp, so use them where they work the best. On a 400 ci engine that will be to make | + | This combo is best at building a lot of torque in the 3,500 rpm range. L31 heads on a 406 will not lend themselves to top end hp, so use them where they work the best. On a 400 ci engine that will be to make bottom end and midrange torque. |
| − | *Keith Black | + | *Keith Black [http://www.summitracing.com/parts/SCA-25700P/ p/n KB168-030 hypereutectic pistons]. |
*Scat Pro Stock 5.7" rods. These rods are clearanced for the cam right out of the box. Minimum clearancing may be necessary at the pan rail for the big end of the rods. | *Scat Pro Stock 5.7" rods. These rods are clearanced for the cam right out of the box. Minimum clearancing may be necessary at the pan rail for the big end of the rods. | ||
6" rods can cause the wrist pin to get up into the oil ring land. This adds a little more complexity and more things to go wrong than if you were to use a 5.7" rod. | 6" rods can cause the wrist pin to get up into the oil ring land. This adds a little more complexity and more things to go wrong than if you were to use a 5.7" rod. | ||
| − | With nominal +/- 66cc heads (production head combustion chamber volumes are often larger than published data), these 22cc D-cup pistons will produce 9.6:1 static compression ratio. An added benefit is the tall 1.433" compression height, meaning less block deck to cut off to reach a target squish of 0.035" to 0.045". | + | With nominal +/- 66cc heads (production head combustion chamber volumes are often larger than published data), these [http://www.summitracing.com/parts/UEM-KB168-030/ 22cc D-cup pistons] will produce 9.6:1 static compression ratio. An added benefit is the tall 1.433" compression height, meaning less block deck to cut off to reach a target squish of 0.035" to 0.045". |
| − | + | Besides boring and honing, machine shop work will include align honing the main bearing bores and cutting the block decks square and to the proper deck height to work with the piston compression height and gasket thickness to set the squish. | |
| − | + | Stock block deck height is +/- 9.025". The height of your stack of parts will be 1.875" for the crank throw radius, 5.700" for the connecting rod center to center and 1.433" for the piston compression height, for a total of 9.008". Using a gasket thickness of 0.039"/0.040", the block decks will have to be cut 0.017" to reach a zero deck. This will put the squish at 0.039" or 0.040", depending on the head gasket used. Decking the block will also insure that the block decks on all four corners of the block are the same distance from the main bearing centerline, meaning that static compression ratio will be closer to equal across all cylinders and will also contribute to the heads and intake manifold lining up and sealing the way they're supposed to. | |
| − | + | Thinner shim head gaskets used to be available for the 400, but not any longer. If 350 shim gaskets are drilled for steam holes, they might have a large enough bore diameter to work on the 400 block, but this has to be carefully checked to be sure there's no overhang of the gasket into the bore. If the shim gasket intrudes into the cylinder/chamber, it could be a potential cause of pre-ignition/detonation. It's better to use a composition gasket that is engineered for the purpose and cut the decks accordingly. Speaking of steam holes, the heads will have to be drilled for them. [[Drilling steam holes in smallblock Chevy heads]] has info on this procedure. | |
| − | + | This build uses a low-cost hydraulic flat tappet cam and the stock L31 valve springs and retainers. The rpm limit with this motor will be 5000, so there's no need to make any changes to the heads except maybe replacing the seals, unless there's a need for new springs. If you want to keep some safety margin (total of at least 0.050" between the 5 coils, and a safety margin for retainer-to-seal clearance), then you should limit valve lift to 0.420- 0.450". There's no need for 1.6 ratio rockers for this build, either. | |
| − | Crane has a cam that uses easy ramps and will fall right into the static compression ratio range we will use in this motor. #10017 has an operating range of 1800-5400. Here's the 100172 kit which includes lifters. Always buy | + | Crane has a cam that uses easy ramps and will fall right into the static compression ratio range we will use in this motor. #10017 has an operating range of 1800-5400. [http://www.summitracing.com/parts/CRN-100172/ '''Here's'''] the p/n 100172 kit which includes lifters. Always buy quality lifters. Get them with the cam if possible. |
| − | + | Crane's description says this cam needs a 2500 converter, but with the amount of torque the engine will make down low a stock converter and a 3.50 gear will suffice. The lobe separation angle of 106 degrees will help make the bottom end torque that's needed for a stock converter and 3.5:1 range rear gears. The 0.450" lift will work with the stock springs and retainers. Be sure to use feeler gauges between the spring coils at full valve lift to insure that the springs don't stack solid. In theory, they shouldn't, but they have to be checked to be sure. Use 16-18 degrees of initial advance with an additional amount of mechanical advance to bring the total initial and mechanical to 34 degrees. That's all you need with these heads. You need more at the crank than you would with a stock cam though, for the motor to idle properly. We need to bring the idle down for use with a stock converter so we don't have to stand on the brake pedal at stoplights. See [[Hot rodding the HEI distributor]] for details on this and for using a vacuum advance. | |
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| − | + | To the long block, add an Edelbrock Performer RPM intake manifold and top it off with a rebuilt Edelbrock Thunder series [http://www.edelbrock.com/automotive...c/thunder.shtml AVS 650 CFM manual choke carburetor] p/n 1805. Also get the Edelbrock choke cable p/n 8013. | |
| − | + | Mount a 14" x 4" air filter on top. Stack two 14 x 2's if you can't find a 4" thick element. This (and any) motor needs to breathe. Bolt on a pair of long-tube 1-5/8" to 1-3/4" headers and connect the two sides of the exhaust system by using either an X or an H pipe right after the collectors. Use the mufflers of your choice. | |
| − | + | ====Results==== | |
| − | + | :'''RPM HP TQ''' | |
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*1500 122 426 | *1500 122 426 | ||
*2000 174 457 | *2000 174 457 | ||
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*5000 373 392 | *5000 373 392 | ||
*5500 326 311 | *5500 326 311 | ||
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There you have it boys and girls, a tire-shredding motor with a "flat-as-a-table" torque curve and a cam that will have a slightly rough idle so the OP can pose cool down at the Sonic Drive-In. | There you have it boys and girls, a tire-shredding motor with a "flat-as-a-table" torque curve and a cam that will have a slightly rough idle so the OP can pose cool down at the Sonic Drive-In. | ||
| − | + | When using a flat tappet cam, break in is uber important. Read up on what to do and how to do it [http://www.crankshaftcoalition.com/...tips_and_tricks '''here''']. | |
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| + | ===350 SBC- Cheap to build/regular fuel street motor=== | ||
| + | *[http://www.summitracing.com/parts/UEM-KB142-030/ These pistons] | ||
| + | *[http://www.summitracing.com/parts/HRS-CL112011-11/ This cam] | ||
| + | *[http://www.crankshaftcoalition.com/wiki/Vortec_L31_cylinder_head '''Vortec L31 heads'''] from a boneyard, casting number 12558062 or 10239906. Magnaflux for cracks. Fit new stock or equivalent springs and seals. Make certain seals are fully seated on the guide boss by tapping them with a socket and small hammer. | ||
| + | *The stock springs will work well with the mild cam and will not pull the rocker studs out of the heads. Doesn't matter whether the heads have hard inserts in the exhaust or induction hardened seats, either will work. Same casting, both styles flow the same. Give them a three angle valve job and backcut the valves if they're not already done. Use the self aligning stock rockers that came on the heads. | ||
| + | *Align hone the main bearing bores in the block and cut the block decks for 9.015" block deck height, referenced off the main bearing bore so that you know the block deck height is equal on all four corners. This will insure that the heads sit level and flat on the deck and that the intake manifold will sit square to the heads with no gaps to cause a vacuum leak. Use GM head gasket #10105117 or equivalent. | ||
| + | *Static compression ratio will be 9.1:1 and squish will be 0.042". Use Edelbrock p/n 7116 Performer RPM intake manifold. A 600cfm carb is all that's needed. | ||
| + | *Makes 365 hp @ 5000 rpm with a double torque peak of 420 ft/lbs @ 3500 and 4000 rpm. Should make this power on regular pump gas without detonation and make for a real nice daily driver motor. | ||
| + | *The cam begins making power at 1200 rpm, so there's little need for a looser converter. A 2000 stall converter would be all that wouold be needed to keep the car from creeping at stoplights and also to get up into the 1500 rpm bottom range of the intake manifold at the hit of the throttle. | ||
==Resources== | ==Resources== | ||
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