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The Terminator
Engine/Tuning
School me on rotating assemblies... school me on cams...
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<blockquote data-quote="MalcolmV8" data-source="post: 15571664" data-attributes="member: 8854"><p>First very sorry about your friend, it's nice that you're continuing his build. </p><p></p><p>Since you're building the motor the motor it makes your goal so much more attainable. Well easier I should say.</p><p>I built a 10.5 SCR motor with flat top pistons. I had -1.64 CC intake reliefs which are .150" and my ring lands moved down .050" for stronger ring lands. That combo with stock .036" head gaskets makes 10.5 CR. Had I left the ring lands alone it would have been closer to 10.7. To give you a guide line.</p><p></p><p>Heads were hand ported by a local guy. Not the greatest job in the world but it worked. I've since had them re-ported by Livernois for this summer.</p><p>I had cams too. Initially the Comp stage 3s which are 238/240. It got complicated because I was having a lot of cam related issues which turned out to be the boost bypass valve actuator from low vacuum conditions caused by the cams.</p><p>I then had some custom grinds made 228/233 but my problems persisted until I figured out the vacuum / boost bypass valve issue. Not to get side tracked but my point is I don't know which set of cams would have been better due to all of that.</p><p></p><p>Anyways that combo with some good headers, 1 7/8" long tubes and a full 3" exhaust with a 2.9 Whipple Crusher made well over 1k to the wheels. I was spinning that blower to 30 PSI.</p><p>Fuel was true E85 ~ E86 as tested. It came out the pump from a local gas station.</p><p></p><p>I was plagued with lower pulleys breaking left and right and after fighting that issue for a while I got rid of the big blower and went with a 2.3 TVS.</p><p></p><p>Even with that tiny TVS at only a peak of 24 PSI the car still made 800 whp at 6k RPMs and I wrapped it to 7500 RPM. The little TVS makes some torque too. 640 ft/lb at only 3k RPMs and by 4k RPMs over 700 ft/lbs and climbing.</p><p></p><p>All that was on stock rods with ARP 2000 bolts. Some have said I was on borrowed time and others seem to think it would have lived forever.</p><p></p><p>This winter I decided to step things up and have gone with domed pistons putting me at 11.5 SCR. I also got the heads re-done by Livernois and mentioned above so I while I was at it I went ahead and threw in some Molnar rods for piece of mind. Perhaps over kill but they're such good bang for the buck and so incredibly strong it made sense.</p><p></p><p>So a good recipe for hitting your goal is going to be bump the compression, use E85 or race fuel and let the motor breath. No restrictions on air going in or out. You'll hit the goal with a 2.9 Whipple but if driven hard you'll be breaking lower pulleys like I did so be warned. I believe the issues comes from the very quick wrapping RPMs of the high compression motor. It's a lot of inertia to be speeding up and down at very rapid rates.</p><p></p><p>Perhaps lower compression motor with big blower and some nitrous to hit goal.</p><p>Or</p><p>High compression motor with smaller blower and some nitrous.</p></blockquote><p></p>
[QUOTE="MalcolmV8, post: 15571664, member: 8854"] First very sorry about your friend, it's nice that you're continuing his build. Since you're building the motor the motor it makes your goal so much more attainable. Well easier I should say. I built a 10.5 SCR motor with flat top pistons. I had -1.64 CC intake reliefs which are .150" and my ring lands moved down .050" for stronger ring lands. That combo with stock .036" head gaskets makes 10.5 CR. Had I left the ring lands alone it would have been closer to 10.7. To give you a guide line. Heads were hand ported by a local guy. Not the greatest job in the world but it worked. I've since had them re-ported by Livernois for this summer. I had cams too. Initially the Comp stage 3s which are 238/240. It got complicated because I was having a lot of cam related issues which turned out to be the boost bypass valve actuator from low vacuum conditions caused by the cams. I then had some custom grinds made 228/233 but my problems persisted until I figured out the vacuum / boost bypass valve issue. Not to get side tracked but my point is I don't know which set of cams would have been better due to all of that. Anyways that combo with some good headers, 1 7/8" long tubes and a full 3" exhaust with a 2.9 Whipple Crusher made well over 1k to the wheels. I was spinning that blower to 30 PSI. Fuel was true E85 ~ E86 as tested. It came out the pump from a local gas station. I was plagued with lower pulleys breaking left and right and after fighting that issue for a while I got rid of the big blower and went with a 2.3 TVS. Even with that tiny TVS at only a peak of 24 PSI the car still made 800 whp at 6k RPMs and I wrapped it to 7500 RPM. The little TVS makes some torque too. 640 ft/lb at only 3k RPMs and by 4k RPMs over 700 ft/lbs and climbing. All that was on stock rods with ARP 2000 bolts. Some have said I was on borrowed time and others seem to think it would have lived forever. This winter I decided to step things up and have gone with domed pistons putting me at 11.5 SCR. I also got the heads re-done by Livernois and mentioned above so I while I was at it I went ahead and threw in some Molnar rods for piece of mind. Perhaps over kill but they're such good bang for the buck and so incredibly strong it made sense. So a good recipe for hitting your goal is going to be bump the compression, use E85 or race fuel and let the motor breath. No restrictions on air going in or out. You'll hit the goal with a 2.9 Whipple but if driven hard you'll be breaking lower pulleys like I did so be warned. I believe the issues comes from the very quick wrapping RPMs of the high compression motor. It's a lot of inertia to be speeding up and down at very rapid rates. Perhaps lower compression motor with big blower and some nitrous to hit goal. Or High compression motor with smaller blower and some nitrous. [/QUOTE]
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