Home » Mechanical Roller Tappet
All our Roller profiles are designed with our exclusive Inverse Radius technology.
Our Inverse Radius designs produce a slow initial opening of the valve, then increases the lift rate as needed per engine specifications.
This design gives you more area under the curve at the same lift and duration then a normal flat flanked roller profile.
The result is less air being lost to the overlap process, and more air being retained in the cylinder.
This makes the engine more efficient, increasing both torque and Horsepower.
SR Roller Series
Introducing our new SR Series mechanical roller profiles for Street/Strip performance. All our new SR Series profiles are designed with our exclusive Inverse Radius technology. These profiles give you the ultimate in performance and reliability for your street/strip application. These profiles are for use with Mechanical Roller tappets with a .750″ diameter wheel. The SR Series Mechanical Roller profiles are for use in both street and racing applications, and require the use of our Mechanical roller lifters and high-rate springs.
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Duration
|
Lobe
|
Valve Lift
|
|||||
|
Part #
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Advertised
|
@.050″
|
Lift
|
1.5
|
1.6
|
1.7
|
|
|
SR66340
|
240°
|
212°
|
.340″
|
.510″
|
.544″
|
.572″
|
|
|
SR66365-11
|
242°
|
217°
|
.365″
|
.531″
|
.566″
|
.601″
|
|
|
SR67296-9
|
244°
|
213°
|
.296″
|
.430″
|
.459″
|
.487″
|
|
|
SR67340
|
244°
|
216°
|
.340″
|
.510″
|
.544″
|
.572″
|
|
|
SR68350
|
248°
|
220°
|
.350″
|
.525″
|
.560″
|
.595″
|
|
|
SR69350
|
252°
|
224°
|
.350″
|
.525″
|
.560″
|
.595″
|
|
|
SR70360
|
256°
|
228°
|
.360″
|
.540″
|
.576″
|
.612″
|
|
|
SR71360
|
260°
|
232°
|
.360″
|
.540″
|
.576″
|
.612″
|
|
|
SR72370
|
264°
|
236°
|
.370″
|
.555″
|
.592″
|
.629″
|
|
|
SR73365
|
268°
|
241°
|
.365″
|
.547″
|
.584″
|
.620″
|
|
|
SR73370
|
268°
|
240°
|
.370″
|
.555″
|
.592″
|
.629″
|
|
|
SR74344
|
272°
|
241°
|
.344″
|
.516″
|
.550″
|
.585″
|
|
|
SR74347
|
272°
|
246°
|
.347″
|
.520″
|
.555″
|
.590″
|
|
|
SR74365
|
272°
|
243°
|
.365″
|
.547″
|
.584″
|
.620″
|
|
|
SR75345
|
276°
|
244°
|
.345″
|
.518″
|
.552″
|
.587″
|
|
|
SR75365
|
276°
|
246°
|
.365″
|
.547″
|
.584″
|
.620″
|
|
|
SR76347
|
278°
|
250°
|
.347″
|
.520″
|
.555″
|
.590″
|
|
|
SR76363-7
|
276°
|
245°
|
.363″
|
.545″
|
.581″
|
.617″
|
|
Asymmetrical I.R. Rollers
Our Asymmetrical I.R. Intake profiles utilize the same design characteristics as our famous Inverse Radius profiles, but with a faster opening
ramp to create more power, and a slower closing ramp for more stability at higher RPM’s. These Intake profiles are for use with Mechanical Roller
tappets with a .750″ – .825″ diameter wheel. The Asymmetrical I.R. profiles are for use in racing applications only, and should only be used as
Intake profiles.
|
.Seat
|
.050″ Duration
|
Lobe
|
Net Lifts
|
||||||
|
Part #
|
Duration
|
Opening
|
Closing
|
Total
|
Lift
|
1.5
|
1.6
|
1.7
|
|
|
R75428A2
|
302°
|
129°
|
125°
|
254°
|
.428″
|
.627″
|
.668″
|
.710″
|
|
|
R76418A
|
304°
|
127°
|
126°
|
253°
|
.418″
|
.612″
|
.652″
|
.693″
|
|
|
R76425A2-7
|
308°
|
127°
|
125°
|
252°
|
.425″
|
.627″
|
.668″
|
.710″
|
|
|
R77435A
|
308°
|
132°
|
128°
|
260°
|
.435″
|
.637″
|
.680″
|
.722″
|
|
|
R77452AS
|
308°
|
130°
|
128.5°
|
258.5°
|
.452”
|
.660”
|
.704”
|
.748”
|
|
|
R77469A-7
|
308°
|
130°
|
128°
|
258°
|
.469″
|
.693″
|
.739″
|
.785″
|
|
|
R78418A
|
312°
|
131°
|
129°
|
260°
|
.418″
|
.612″
|
.652″
|
.693″
|
|
|
R78421AR
|
312°
|
131°
|
129°
|
260°
|
.421″
|
.617″
|
.657″
|
.699″
|
|
|
R78452AS
|
312°
|
131.5°
|
130°
|
261.5°
|
.452”
|
.660”
|
.704”
|
.748”
|
|
|
R78469-7
|
312°
|
132°
|
130°
|
262°
|
.469″
|
.693″
|
.739″
|
.785″
|
|
|
R78367A2
|
314°
|
131°
|
129.5°
|
260.5°
|
.367″
|
.535″
|
.571″
|
.606″
|
|
|
R78450A2
|
314°
|
133°
|
131°
|
264°
|
.450″
|
.660″
|
.704″
|
.748″
|
|
|
R79390A
|
316°
|
131°
|
130°
|
262°
|
.390″
|
.570″
|
.608″
|
.646″
|
|
|
R79421AR
|
316°
|
132°
|
131°
|
263°
|
.421″
|
.617″
|
.657″
|
.699″
|
|
|
R79452AS
|
316°
|
133.5°
|
132°
|
265.5°
|
.452”
|
.660”
|
.704”
|
.748”
|
|
|
R80420A
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320°
|
136°
|
132°
|
268°
|
.420″
|
.615″
|
.656″
|
.697″
|
|
Inverse Radius Rollers
Our Inverse Radius Roller profiles produce a slow initial opening of the valve, then increases the lift rate as needed
per engine specifications. This design gives you more area under the curve at the same lift and duration than a
normal flat flanked roller profile. The result is less air being lost to the overlap process, and more air being retained in
the cylinder. This makes the engine more efficient, increasing both torque and horsepower. These profiles are of
ruse with Mechanical Roller tappets with a .750″ – .825″ diameter wheel. The Inverse Radius Roller profiles are for
use in racing applications only, and can be used as Intake or Exhaust profiles.
|
Duration
|
Lobe
|
Net Lifts
|
|||||
|
Part #
|
Seat
|
.050″
|
Lift
|
1.5
|
1.6
|
1.7
|
|
|
R64352
|
256°
|
210°
|
.352″
|
.511″
|
.545″
|
.579″
|
|
|
R68400
|
272°
|
226°
|
.400”
|
.582”
|
.621”
|
.660”
|
|
|
R70400
|
280°
|
233°
|
.400”
|
.582”
|
.621”
|
.660”
|
|
|
R71390
|
284°
|
236°
|
.390″
|
.568″
|
.606″
|
.644″
|
|
|
R72350
|
288°
|
236°
|
.350″
|
.508″
|
.542″
|
.576″
|
|
|
R72380A10
|
288°
|
239°
|
.380”
|
.555”
|
.592”
|
.629”
|
|
|
R72395
|
288°
|
240°
|
.395″
|
.575″
|
.614″
|
.653″
|
|
|
R73346
|
292°
|
238°
|
.346″
|
.503″
|
.538″
|
.572″
|
|
|
R73400
|
292°
|
243°
|
.400″
|
.584″
|
.624″
|
.664″
|
|
|
R73401
|
292°
|
244°
|
.401″
|
.586″
|
.626″
|
.667″
|
|
|
R74347DP
|
296°
|
246°
|
.347″
|
.505″
|
.539″
|
.572″
|
|
|
R74375-10
|
296°
|
245°
|
.375”
|
.548”
|
.584”
|
.621”
|
|
|
R74406
|
296°
|
248°
|
.406″
|
.593″
|
.634″
|
.674″
|
|
|
R74410-10
|
296°
|
244°
|
.410″
|
.600″
|
.640″
|
.680″
|
|
|
R74425
|
296°
|
248°
|
.425″
|
.622″
|
.664″
|
.707″
|
|
|
R75425
|
300°
|
252°
|
.425″
|
.622″
|
.664″
|
.707″
|
|
|
R75438
|
300°
|
254°
|
.438″
|
.641″
|
.685″
|
.729″
|
|
|
R76347DP
|
304°
|
250°
|
.347″
|
.505″
|
.539″
|
.572″
|
|
|
R76358
|
304°
|
252°
|
.358″
|
.521″
|
.557″
|
.593″
|
|
|
R76410-10
|
304°
|
252°
|
.410″
|
.600″
|
.640″
|
.680″
|
|
|
R76412
|
304°
|
254°
|
.412″
|
.602″
|
.643″
|
.684″
|
|
|
R76417
|
304°
|
255°
|
.417″
|
.610″
|
.651″
|
.693″
|
|
|
R76424
|
304°
|
255°
|
.424″
|
.620″
|
.662″
|
.705″
|
|
|
R76424BW
|
304°
|
254°
|
.424″
|
.620″
|
.662″
|
.705″
|
|
|
R76434
|
304°
|
256°
|
.434″
|
.635″
|
.678″
|
.722″
|
|
|
R76442
|
304°
|
256°
|
.442″
|
.647″
|
.691″
|
.735″
|
|
|
R77315
|
308°
|
252°
|
.315″
|
.457″
|
.488″
|
.520″
|
|
|
R77385
|
308°
|
255°
|
.385″
|
.562″
|
.600″
|
.639″
|
|
|
R77424
|
308°
|
258°
|
.424″
|
.620″
|
.662″
|
.705″
|
|
|
R77425BW
|
308°
|
257°
|
.424″
|
.620″
|
.662″
|
.705″
|
|
|
R77425
|
308°
|
260°
|
.424″
|
.622″
|
.664″
|
.707″
|
|
|
R77434
|
308°
|
260°
|
.434″
|
.635″
|
.678″
|
.722″
|
|
|
R77444
|
308°
|
260°
|
.444″
|
.650″
|
.694″
|
.739″
|
|
|
R78322
|
312°
|
254°
|
.322″
|
.467″
|
.499″
|
.521″
|
|
|
R78372
|
312°
|
256°
|
.372″
|
.542″
|
.579″
|
.616″
|
|
|
R78390
|
312°
|
258°
|
.390″
|
.569″
|
.608″
|
.647″
|
|
|
R78398
|
312°
|
259°
|
.398″
|
.581″
|
.621″
|
.661″
|
|
|
R78410
|
312°
|
262°
|
.410″
|
.599″
|
.640″
|
.681″
|
|
|
R78417HC
|
312°
|
262°
|
.417″
|
.611″
|
.651″
|
.692″
|
|
|
R78421
|
312°
|
261°
|
.421″
|
.616″
|
.658″
|
.700″
|
|
|
R78424
|
312°
|
262°
|
.424″
|
.620″
|
.662″
|
.705″
|
|
|
R78425
|
312°
|
264°
|
.425″
|
.622″
|
.664″
|
.707″
|
|
|
R78430
|
312°
|
262°
|
.430″
|
.629″
|
.672″
|
.715″
|
|
|
R78437
|
312°
|
262°
|
.437″
|
.640″
|
.683″
|
.727″
|
|
|
R78440
|
312°
|
262°
|
.440″
|
.642″
|
.685″
|
.728″
|
|
|
R78453
|
312°
|
264°
|
.453″
|
.664″
|
.709″
|
.754″
|
|
|
R78480
|
312°
|
262°
|
.480″
|
.702″
|
.749″
|
.795″
|
|
|
R79388
|
316°
|
262°
|
.388″
|
.567″
|
.605″
|
.643″
|
|
|
R79392
|
316°
|
262°
|
.392″
|
.572″
|
.612″
|
.651″
|
|
|
R79425
|
316°
|
265°
|
.425″
|
.622″
|
.664″
|
.707″
|
|
|
R79429
|
316°
|
266°
|
.429″
|
.628″
|
.670″
|
.713″
|
|
|
R79431
|
316°
|
264°
|
.431″
|
.630″
|
.673″
|
.717″
|
|
|
R79450
|
316°
|
267°
|
.450″
|
.657″
|
.700″
|
.744″
|
|
|
R79465
|
316°
|
263°
|
.465″
|
.679″
|
.724″
|
.770″
|
|
|
R79480
|
316°
|
266°
|
.480″
|
.702″
|
.748″
|
.795″
|
|
|
R80346
|
320°
|
260°
|
.346″
|
.503″
|
.538″
|
.572″
|
|
|
R80362
|
320°
|
262°
|
.362″
|
.526″
|
.561″
|
.596″
|
|
|
R80367HC
|
320°
|
262°
|
.367″
|
.535″
|
.571″
|
.606″
|
|
|
R80393
|
320°
|
264°
|
.393″
|
.573″
|
.614″
|
.644″
|
|
|
R80412
|
320°
|
268°
|
.412″
|
.602″
|
.643″
|
.684″
|
|
|
R80417HC
|
320°
|
269°
|
.417″
|
.611″
|
.651″
|
.692″
|
|
|
R80424
|
320°
|
272°
|
.424″
|
.620″
|
.662″
|
.705″
|
|
|
R80432
|
320°
|
269°
|
.432″
|
.631″
|
.673″
|
.715″
|
|
|
R80440
|
320°
|
269°
|
.440″
|
.642″
|
.685″
|
.728″
|
|
|
R80444
|
320°
|
266°
|
.444″
|
.650″
|
.694″
|
.739″
|
|
|
R80465
|
320°
|
270°
|
.465”
|
.680”
|
.725”
|
.770”
|
|
|
R81332-10
|
324°
|
261°
|
.332″
|
.483″
|
.515″
|
.547″
|
|
|
R81437
|
324°
|
273°
|
.437″
|
.638″
|
.680″
|
.723″
|
|
|
R81538
|
324°
|
277°
|
.538″
|
.789″
|
.842″
|
.894″
|
|
|
R82362
|
328°
|
268°
|
.362″
|
.527″
|
.563″
|
.599″
|
|
|
R82401
|
328°
|
272°
|
.401″
|
.585″
|
.626″
|
.666″
|
|
|
R82412
|
328°
|
273°
|
.412″
|
.600″
|
.640″
|
.680″
|
|
|
R82426
|
328°
|
274°
|
.426″
|
.623″
|
.665″
|
.708″
|
|
|
R82436
|
328°
|
276°
|
.436″
|
.638″
|
.681″
|
.725″
|
|
|
R82448
|
328°
|
277°
|
.448″
|
.656″
|
.701″
|
.746″
|
|
|
R82465
|
328°
|
277°
|
.465”
|
.680”
|
.725”
|
.770”
|
|
|
R82495
|
328°
|
278°
|
.495″
|
.727″
|
.776″
|
.826″
|
|
|
R83373
|
332°
|
272°
|
.373″
|
.544″
|
.581″
|
.618″
|
|
|
R83436
|
332°
|
279°
|
.436″
|
.636″
|
.678″
|
.721″
|
|
|
R83472
|
332°
|
282°
|
.472″
|
.692″
|
.739″
|
.786″
|
|
|
R83500
|
332°
|
273°
|
.500″
|
.732″
|
.780″
|
.829″
|
|
|
R83538
|
332°
|
284°
|
.538″
|
.789″
|
.842″
|
.894″
|
|
|
R84363
|
336°
|
272°
|
.363″
|
.529″
|
.565″
|
.601″
|
|
|
R84389
|
336°
|
277°
|
.389″
|
.568″
|
.606″
|
.645″
|
|
|
R84412
|
336°
|
280°
|
.412”
|
.600”
|
.640”
|
.680”
|
|
|
R84436
|
336°
|
282°
|
.436″
|
.636″
|
.678″
|
.720″
|
|
|
R84455
|
336°
|
282°
|
.455″
|
.664″
|
.709″
|
.753″
|
|
|
R84472
|
336°
|
288°
|
.472″
|
.691″
|
.737″
|
.783″
|
|
|
R84488
|
336°
|
286°
|
.488″
|
.716″
|
.765″
|
.814″
|
|
|
R84500
|
336°
|
285°
|
.500”
|
.732”
|
.781”
|
.830”
|
|
|
R85373
|
340°
|
278°
|
.373″
|
.544″
|
.581″
|
.618″
|
|
|
R85510
|
340°
|
289°
|
.510”
|
.747”
|
.797”
|
.847”
|
|
|
R86397
|
344°
|
282°
|
.397″
|
.579″
|
.617″
|
.656″
|
|
|
R86406
|
344°
|
284°
|
.406″
|
.593″
|
.634″
|
.674″
|
|
|
R86436
|
344°
|
288°
|
.446″
|
.638″
|
.681″
|
.725″
|
|
|
R86446
|
344°
|
290°
|
.446″
|
.653″
|
.698″
|
.742″
|
|
|
R86465
|
344°
|
291°
|
.465″
|
.680″
|
.725″
|
.770″
|
|
|
R86485
|
344°
|
284°
|
.485″
|
.709″
|
.756″
|
.804″
|
|
|
R86495
|
344°
|
296°
|
.495″
|
.725″
|
.774″
|
.823″
|
|
|
R86525
|
344°
|
292°
|
.525″
|
.769″
|
.820″
|
.872″
|
|
|
R87335
|
348°
|
288°
|
.335″
|
.487″
|
.520″
|
.557″
|
|
|
R87389
|
348°
|
290°
|
.389″
|
.568″
|
.606″
|
.645″
|
|
|
R87465
|
348°
|
294°
|
.465″
|
.680″
|
.725″
|
.770″
|
|
|
R88373
|
352°
|
288°
|
.373″
|
.544″
|
.581″
|
.618″
|
|
|
R88455
|
352°
|
298°
|
.455″
|
.667″
|
.712″
|
.758″
|
|
|
R88528
|
352°
|
300°
|
.528″
|
.774″
|
.826″
|
.877″
|
|
|
R89351
|
356°
|
288°
|
.351″
|
.511″
|
.546″
|
.581″
|
|
|
R89455
|
356°
|
300°
|
.455″
|
.667″
|
.712″
|
.758″
|
|
|
R89480
|
356°
|
302°
|
.480”
|
.702”
|
.749”
|
.796”
|
|
|
R90530-2
|
362°
|
310°
|
.530″
|
.777″
|
.829″
|
.881″
|
|
|
R91480
|
364°
|
309°
|
.480”
|
.702”
|
.749”
|
.796”
|
|
AK435 Series
The AK435 series Intake profiles utilize the fastest accelerating opening ramps
in the industry to create more H.P. and Torque, while the ultra-smooth closing
ramps make the AK435 series remarkably easy on your valvetrain.
The AK435 series profiles are for racing applications only, and should only
be used as intake profiles.
|
Seat
|
.050″ Duration
|
Lobe
|
Net Lifts
|
|||||
|
Part #
|
Duration
|
Opening
|
Closing
|
Total
|
Lift
|
1.5
|
1.6
|
1.7
|
|
R74435AK
|
296°
|
124°
|
123°
|
247°
|
.435″
|
.637″
|
.680″
|
.722″
|
|
R76435AK
|
304°
|
128°
|
126°
|
254°
|
.435″
|
.637″
|
.680″
|
.722″
|
|
R77435AK
|
308°
|
130°
|
128°
|
258°
|
.435″
|
.637″
|
.680″
|
.722″
|
|
R78435AK
|
314°
|
133°
|
130°
|
263°
|
.435″
|
.637″
|
.680″
|
.722″
|
|
R79435AK
|
318°
|
135°
|
132°
|
267°
|
.435″
|
.637″
|
.680″
|
.722″
|
|
R81435AK
|
324°
|
137°
|
133°
|
270°
|
.435″
|
.637″
|
.680″
|
.722″
|
|
R82435AK
|
328°
|
138°
|
136°
|
274°
|
.435″
|
.637″
|
.680″
|
.722″
|
New “Sprint Series”
I.R. Roller Profiles
New for 2015 is our line of “Sprint Series” Inverse Radius Roller profiles.
These profiles are designed specifically for the extreme performance
demands of today’s Sprint and Latemodel race engines. Using our
“Parametric Profile” design equation, these lobe profile designs are
optimized for 400-420ci V8 engines.
These profiles are designed specifically for the extreme performance
demands of today’s Sprint and Latemodel race engines. Using our
“Parametric Profile” design equation, these lobe profile designs are
optimized for 400-420ci V8 engines.
| Duration @ | Lobe | ||||
| Part # | Seat | .020″ | .050″ | .200″ | Lift |
| R78465s | 312° | 292° | 264° | 189° | .465″ |
| R78480s | 312° | 292° | 264° | 190° | .480″ |
| R78453s | 312° | 296° | 266° | 190° | .453″ |
| R79465s | 316° | 296° | 267° | 191° | .465″ |
| R79480s | 316° | 296° | 267° | 192° | .480″ |
| R79450s | 316° | 300° | 269° | 193° | .450″ |
| R80465s | 320° | 300° | 270° | 194° | .465″ |
| R81465s | 324° | 303° | 274° | 196° | .465″ |
| R82465s | 328° | 307° | 277° | 199° | .465″ |