Turbo & Supercharged Cams
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Joined: Sep 2003
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From: TX
A word of advice on doing cam testing a turbo car. Whoever is doing your testing, you need to be logging EMAP and shaft speed on the turbo. We tested 4 different grind profiles on the white drag s2000 we built last season. From really big to almost OEM. The big cams were great at low psi levels, as boost went up EMAP went to crap and efficiency fell way off. The cam was limiting our power potential. As we went down in lift and duration, our gains at low psi levels were not as impressive but as the boost was increased EMAP was much lower and efficiency was better. We were able to get more power/torque with higher pressure ratios. The trend went this way as the cams went smaller. We ended up using the smallest profile in the engine, made the most power as well. Our EMAP/efficiency was much better as well.
The problem I see is that the testing will show great gains at lower psi levels that most of the engines will see on pump gas, but when boost is increased efficiency will be down and power will suffer. Kings is running OEM cams in their drag cars, and I might be switching back to OEM in ours as well from the trend I have been seeing. Getting EMAP and shaft speed will give you the lost pieces of the puzzle to knowing what is going on with engine and turbo efficiency, instead of speculating and making educated guesses. I know personally what kind of time and money it takes to test things like this, so hats off to making something happen.
The problem I see is that the testing will show great gains at lower psi levels that most of the engines will see on pump gas, but when boost is increased efficiency will be down and power will suffer. Kings is running OEM cams in their drag cars, and I might be switching back to OEM in ours as well from the trend I have been seeing. Getting EMAP and shaft speed will give you the lost pieces of the puzzle to knowing what is going on with engine and turbo efficiency, instead of speculating and making educated guesses. I know personally what kind of time and money it takes to test things like this, so hats off to making something happen.
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Joined: May 2002
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From: Raleigh, NC
I have supercharged and turbo'd cars here in the shop we can use for testing. dyno in house 
the turbo car has a bw efr turbo so we can log shaft speed, i doubt the owner would let me drill and weld into a brand new coated full race manifold for emap pressure. This is a pump gas only motor, 400-500hp.
the supercharged car has SOS novi1200 kit, makes 20lbs at 9800 rpms, close to 500hp. It will be on race gas, it is mostly a track day car. we are currently running ap1 cams with k24 rockers in a vtec killer configuration. This thing wants to be on the high cam all the time.
the turbo car has a bw efr turbo so we can log shaft speed, i doubt the owner would let me drill and weld into a brand new coated full race manifold for emap pressure. This is a pump gas only motor, 400-500hp.
the supercharged car has SOS novi1200 kit, makes 20lbs at 9800 rpms, close to 500hp. It will be on race gas, it is mostly a track day car. we are currently running ap1 cams with k24 rockers in a vtec killer configuration. This thing wants to be on the high cam all the time.
Thread Starter
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Joined: Sep 2003
Posts: 2,480
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From: TX
I have supercharged and turbo'd cars here in the shop we can use for testing. dyno in house
the turbo car has a bw efr turbo so we can log shaft speed, i doubt the owner would let me drill and weld into a brand new coated full race manifold for emap pressure. This is a pump gas only motor, 400-500hp.
the supercharged car has SOS novi1200 kit, makes 20lbs at 9800 rpms, close to 500hp. It will be on race gas, it is mostly a track day car. we are currently running ap1 cams with k24 rockers in a vtec killer configuration. This thing wants to be on the high cam all the time.
the turbo car has a bw efr turbo so we can log shaft speed, i doubt the owner would let me drill and weld into a brand new coated full race manifold for emap pressure. This is a pump gas only motor, 400-500hp.
the supercharged car has SOS novi1200 kit, makes 20lbs at 9800 rpms, close to 500hp. It will be on race gas, it is mostly a track day car. we are currently running ap1 cams with k24 rockers in a vtec killer configuration. This thing wants to be on the high cam all the time.
We have a good turbo candidate lined up.
We are looking for a more typical supercharger set up with 7-15PSI & VTEC. If we get that to work, I am sure we can make a VTEC only set for y'all.
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From: TX
Still looking for a Supercharger Tester?
Again if the cams dont work we will buy them back. If they do, you can keep them at a discounted price.
Let us know, we have a turbo tester, need a SC tester.
Again if the cams dont work we will buy them back. If they do, you can keep them at a discounted price.
Let us know, we have a turbo tester, need a SC tester.
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From: New England
Hmmmmmm, high cam - duration cam - defeat the functionality of a forced induction car.
A little isn't bad. Most of the turbo honda vtec engines run much more overlap. It will move the power band up in the RPM range more.
Too much and you will be throwing boost into the exhaust system.
A little isn't bad. Most of the turbo honda vtec engines run much more overlap. It will move the power band up in the RPM range more.
Too much and you will be throwing boost into the exhaust system.
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Hmmmmmm, high cam - duration cam - defeat the functionality of a forced induction car.
A little isn't bad. Most of the turbo honda vtec engines run much more overlap. It will move the power band up in the RPM range more.
Too much and you will be throwing boost into the exhaust system.
A little isn't bad. Most of the turbo honda vtec engines run much more overlap. It will move the power band up in the RPM range more.
Too much and you will be throwing boost into the exhaust system.