read post #7 first, and if your buying a turbo cam you want limited overlap, early exhaust closing and try to select a turbo cam with a max lift in the range of 30%-35% of the intake valve diameter.
http://store.summitracing.com/egnsearch ... 115+307987
http://www.corvettefever.com/techarticl ... index.html
http://www.dougherbert.com/blowercamsch ... 0_633.html
http://www.peregrinesupercars.com/Camshafts.htm
https://www.hotrod.com/articles/ctrp-1106-turbo-camshaft-guide/
http://www.carcraft.com/techarticles/ct ... index.html
http://www.hotrod.com/pitstop/hrdp_1011 ... index.html
https://www.procharger.com/catalogs/ProCharger_Corvette_catalog.pdf
keep in mind limited overlap and extended duration cam timing on the exhaust timing on superchargers is fairly common , on turbos limited exhaust duration to limit back flow is more common, but turbos work best with higher exhaust pressure so the EVO is delayed and the wider LSA is used. but in both cases lower static compression and larger port cross sectional areas tend to help volumetric efficiency, compared to a N/A engine combo
When your using this style TURBO CAM the exhaust duration is usually some 5 to 10 degrees smaller in duration, but it holds the valve open a bit later. The reason is you don't want an early evo because you're blowing the cylinder down when you do this, so we gotta remove the duration so the exhaust valve starts to open later when there is more pressure in the exhaust gasses in the cylinder which results in increased pressure that tends to help spooling the turbo up faster due to that increased pulse pressure, Below is the type/style of hydraulic roller camshaft I would use with a super or turbo build with heads that flowed like the AFR 210cc on a SBC of about 406 displacement and about 8:1 static compression,obviously many parts would be similar but obviously some need to match each application
this style turbo cam,
240/232 @.050" tappet lift
.635"/.600" with 1.6/1.6 rocker arms
110 lobe center, installed at 110 intake center line
A crank driven supercharger on a similar engine would have a vaguely similar cam
centrifugal supercharger cam,
240/248 @.050" tappet lift
.635"/.630" with 1.6/1.6 rocker arms
113 lobe center, installed at 110 intake center line
you could improve the engine efficiency with a super charger equipped engine combo,with a bit longer intake and extended exhaust duration increase lift and a wider LSA.
obviously you'll want to verify clearances
https://www.crower.com/camshafts/ch...orced-induction-noscam-small-base-circle.html
related useful info you should read
http://garage.grumpysperformance.co...lsa-effects-your-compression-torque-dcr.1070/
https://itstillruns.com/choose-cams-supercharger-7959078.html
https://www.enginelabs.com/engine-tech/inside-forced-induction-camshaft-designs-howards-cams/
http://www.kcams.co.nz/Menu/Selecting-A-Camshaft.php
http://garage.grumpysperformance.com/index.php?threads/supercharger-and-turbo-cams.1226/
https://www.hotrod.com/articles/hrdp-1011-cams-for-turbocharged-engines/
https://www.hotrod.com/articles/ctrp-1106-turbo-camshaft-guide/
http://store.summitracing.com/egnsearch ... 115+307987
http://www.corvettefever.com/techarticl ... index.html
http://www.dougherbert.com/blowercamsch ... 0_633.html
http://www.peregrinesupercars.com/Camshafts.htm
https://www.hotrod.com/articles/ctrp-1106-turbo-camshaft-guide/
http://www.carcraft.com/techarticles/ct ... index.html
http://www.hotrod.com/pitstop/hrdp_1011 ... index.html
https://www.procharger.com/catalogs/ProCharger_Corvette_catalog.pdf
keep in mind limited overlap and extended duration cam timing on the exhaust timing on superchargers is fairly common , on turbos limited exhaust duration to limit back flow is more common, but turbos work best with higher exhaust pressure so the EVO is delayed and the wider LSA is used. but in both cases lower static compression and larger port cross sectional areas tend to help volumetric efficiency, compared to a N/A engine combo
When your using this style TURBO CAM the exhaust duration is usually some 5 to 10 degrees smaller in duration, but it holds the valve open a bit later. The reason is you don't want an early evo because you're blowing the cylinder down when you do this, so we gotta remove the duration so the exhaust valve starts to open later when there is more pressure in the exhaust gasses in the cylinder which results in increased pressure that tends to help spooling the turbo up faster due to that increased pulse pressure, Below is the type/style of hydraulic roller camshaft I would use with a super or turbo build with heads that flowed like the AFR 210cc on a SBC of about 406 displacement and about 8:1 static compression,obviously many parts would be similar but obviously some need to match each application
this style turbo cam,
240/232 @.050" tappet lift
.635"/.600" with 1.6/1.6 rocker arms
110 lobe center, installed at 110 intake center line
A crank driven supercharger on a similar engine would have a vaguely similar cam
centrifugal supercharger cam,
240/248 @.050" tappet lift
.635"/.630" with 1.6/1.6 rocker arms
113 lobe center, installed at 110 intake center line
you could improve the engine efficiency with a super charger equipped engine combo,with a bit longer intake and extended exhaust duration increase lift and a wider LSA.
obviously you'll want to verify clearances
https://www.crower.com/camshafts/ch...orced-induction-noscam-small-base-circle.html
related useful info you should read
http://garage.grumpysperformance.co...lsa-effects-your-compression-torque-dcr.1070/
https://itstillruns.com/choose-cams-supercharger-7959078.html
https://www.enginelabs.com/engine-tech/inside-forced-induction-camshaft-designs-howards-cams/
http://www.kcams.co.nz/Menu/Selecting-A-Camshaft.php
http://garage.grumpysperformance.com/index.php?threads/supercharger-and-turbo-cams.1226/
https://www.hotrod.com/articles/hrdp-1011-cams-for-turbocharged-engines/
https://www.hotrod.com/articles/ctrp-1106-turbo-camshaft-guide/
Supercharged / Turbo Charged
Supercharged engines typically have a shorter intake, longer exhaust, and wider lobe center angle (LCA).
Supercharged engines can continue pushing charge into the cylinder longer than an NA (normally asperated) engine, and also the greater pressure differential between the manifold and the cylinder means the cylinder is filled quicker. This means they like a shorter intake duration on a later centerline, compared to thier NA counterparts.
Higher cylinder pressure after combustion means more gas to get rid of, so the exhaust valve is opened earlier than on an NA engine. This means longer exhaust duration, on an earlier centerline.
Early exhaust centerline and late intake centerline means a wider LCA. This means there is less overlap which also helps stop the pressurized intake charge being lost out the exhaust valve.
Turbo Charged engines are more complicated.
Before the turbo charger reaches an efficient speed the engine behaves much like an NA engine, albeit a low compression one. This means to get the cylinder filled efficiently and producing good amounts of exhaust gas to 'spool up' the turbo the ideal would be a relatively tight LCA. However once the turbo has 'spooled up' and is efficient the engine behaves more like a conventional supercharged engine and wants a wider LCA.
Turbo engine camshaft selection, and the overall performance of the engine, is greatly effected by the turbo selection.
It is easier to get a turbo to spool up at lower rpm by choosing a smaller exhaust turbine housing than by manipulating cams. This means the cams can then be optimised for 'on boost' performance.
Typically higher boost levels, and higher rpm, require more cam duration. The main difference between supercharged and turbo charged engines, is that turbo engines do not flow from the intake out the exhaust, at overlap, as easily as a supercharged engine, and therefore tend to open the intake valve earlier. So turbo engines tend to have a longer duration intake than a supercharged engine, but still shorter than an NA engine.
The turbo charger should be selected before the camshaft, remembering that a turbo, much like a supercharger, can restrict power if it is not big enough.
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