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PRC 237 Cathedral port heads.
Cam Motion Torquer cam for cathedral heads - 233/240 @ 116 LSA
Fast 102 for cathedral heads.
One thing that I clearly noticed is how smooth the engine is, it has absolutely no surging at all at any RPM, and the throttle response is much sharper.
The car made 484 hp and 444 tq at the rear wheels. (at the same dyno in a very similar conditions).
My tuner thinks that my 3200 rpm torque converter is robbing alot of hp, hence the low numbers.
I don't care about that, as when I drove the car back it really pulling!
here is the dyno screen shot, I accidently snapped that photo with the mph scale instead of rpm, so I'm not sure at what rpm those numbers were!
Congrats! very good results from medium (some would say small)
Cam through a stalled auto. Car must be a blast to drive with
Throttle response every where and great Driveability.
Great cam choice! Where is the peak HP RPM?
Now thats a huge downgrade in terms of CFM, but yet I managed to gain 16 hp and 23 ft/lbs at the wheels, and above all, I gained a near-stock drivability and less exhaust noise.
Thanks for Cam Motion for their camshaft recommendation, its exactly what I wanted.
I managed to gain 16 hp and 23 ft/lbs at the wheels, and above all, I gained a near-stock drivability and less exhaust noise.
Thanks for Cam Motion for their camshaft recommendation, its exactly what I wanted.
Kamaro, we are very happy to hear that you have the results you wanted!
You are not alone in wanting the extra power of a stroker, but also wanting a great driving experience. The Cam Motion Stealthy Stroker cams are made to deliver just that.
Kamaro
What were the Torque & Horsepower RPM Peaks for both Set-ups?
Not a fan of the GM L92 heads but as KW Baraka pointed
out the overlaps between the 2 combos are HUGE and
Definitely stacked against the L92, would be curious to
have seen the L92 combo with 228*/238* 114*+3*,
I realize hindsight is 20/20 but it would have been
a better comparison IMO.
Again congrats on your results with the new combo.
Kamaro
What were the Torque & Horsepower RPM Peaks for both Set-ups?
Not a fan of the GM L92 heads but as KW Baraka pointed
out the overlaps between the 2 combos are HUGE and
Definitely stacked against the L92, would be curious to
have seen the L92 combo with 228*/238* 114*+3*,
I realize hindsight is 20/20 but it would have been
a better comparison IMO.
Again congrats on your results with the new combo.
Remember, this is a 416 and not a 6L... so even the other cam isn't really that big. The BTR cam was designed for LS3 heads and has done 550rwhp with them.
But the cathedrals are less affected by overlap, so you could throw more cam at the cathedrals and not lose any torque or drivability and gain even more power - so just swapping heads would have likely resulted in even more power than the OP has even now with somewhat improved drivability.
So it's a pretty interesting comparison for the ongoing discussion between LS3 and cathedral port architectures. And for street cars, it's hard to honestly vote for the LS3 architecture for part-throttle or low and mid-range RPM power over Cathedrals.
Remember, this is a 416 and not a 6L... so even the other cam isn't really that big. The BTR cam was designed for LS3 heads and has done 550rwhp with them.
But the cathedrals are less affected by overlap, so you could throw more cam at the cathedrals and not lose any torque or drivability and gain even more power - so just swapping heads would have likely resulted in even more power than the OP has even now with somewhat improved drivability.
So it's a pretty interesting comparison for the ongoing discussion between LS3 and cathedral port architectures. And for street cars, it's hard to honestly vote for the LS3 architecture for part-throttle or low and mid-range RPM power over Cathedrals.
Agreed, Tony usually specs ~243* Intake duration with his 235 CC
Cathedral head on a 416" for a street car, 10* larger then
Kamaro's cam, my point was to approximate the airflow
Going from large port & large cam to a medium port &
Small cam (for a 416") my suggested specs would have
Been similar in air flow & driving dynamics to his cathedral
Combo, both being a little on the smaller side.
Jake
Let's get your 440" Build going with a MMS LS7 Top-End or your
Build will be longer then mine was LOL! Although I'm sure
I have a few, more then a few years on you.
And 600lb less and through a 6 speed with ridiculously light clutch setups. Never happen with a overdrive auto. Imo.
At 3600 lbs according to Jake he less than 400 lbs heavier then a
stock C6ZO6, the RPS BC2 clutches Tony recommends are significantly
lighter then stock @~30lbs but not the textralia 17 lbs which I
agree are ridiculously light. A well built 440" with MMS LS7, MSD,LLSR
with attention to detail should/could make ~630 RWHP through an
auto VS 680 RWHP M6.
Is 50 RWHP difference between a Manual & 4000 Stall Auto reasonable?
I realize cathedral port heads are a nice choice for a LS3 416, but how cam some of these guys get such killer numbers with ported LS3 head and a LLSR? DO you think that the benefits of the solid cam enhance the added CFM and therefore the volosity of the charge? Does this make any sense or what? I wish someon would so a LLSR street driven 416 w/ TFS 235s or MMS 235s. This would take the hyd. lifter and rocker problems out of the equation.
Great results. Im not surprise at all honestly. Why? Its three other threads beside this one that i know of where guys have more power with a cathedral heads over a ported LS3 head.
Pat G on his G8. Car picked like crazy using AFR 230s out the box. Single pattern cam.
Veeee8 on a caddy made a big increase over ported L92 heads with some TFS 235s.
MikeC on his ws6 402ci car. Car had a single plane intake with ported cnc L92 heads by one of the best. Car went 10.8s @ 127 mph with a Pat G cam. He ditched the top end for a ported fast intake with TEA TFS 235s. Car went 10.4s at 132mph with a Pat G cam.
Car now is more streetable and funner to drive. On the dyno it was 15 rwtq all the threw the entire power band and 20 more horses at peak.
I realize cathedral port heads are a nice choice for a LS3 416, but how cam some of these guys get such killer numbers with ported LS3 head and a LLSR? DO you think that the benefits of the solid cam enhance the added CFM and therefore the volosity of the charge? Does this make any sense or what? I wish someon would so a LLSR street driven 416 w/ TFS 235s or MMS 235s. This would take the hyd. lifter and rocker problems out of the equation.
Because the LS3 heads flow a lot more... at .600+ compared to the cathedrals and are far more efficient uptop. So using a high lift solid setup actually makes use of the advantage of the head. The issue is you need a manifold to take advantage of the higher lift as well as the RPM needed to make it work. The bigger, higher flowing ports, when combined with a solid roller and the appropriate manifold, are a good combo for making power at higher engine speeds. Part-throttle and lower RPM ranges... this is where the cathedral offers something over the LS3 architecture.
Because the LS3 heads flow a lot more... at .600+ compared to the cathedrals and are far more efficient uptop. So using a high lift solid setup actually makes use of the advantage of the head. The issue is you need a manifold to take advantage of the higher lift as well as the RPM needed to make it work. The bigger, higher flowing ports, when combined with a solid roller and the appropriate manifold, are a good combo for making power at higher engine speeds. Part-throttle and lower RPM ranges... this is where the cathedral offers something over the LS3 architecture.
That's a good post, Jake. I have a friend who didn't do much internally to his LS3, but when he put higher ratio rockers on the stock cam, the car responded like nobody expected. From the factory, the cam lift is only 0.520-0.550. You get the lift into the .630 or higher range, and then you start to feel what those heads can do. Conversely, you see many cathedral heads running out of steam between .600 and .650 lift
It goes back to understanding the entire combination and camming appropriately for the heads, the intended RPM range, the intake, and the exhaust. LLSR cams tend to go into higher lift, which takes better advantage of the LS3 head flow. Edit - They can get away with it, because of the stability offered byt he solids over hydrualics.
One thought to put out there.... If you have two similar 416 engines through the same transmission and gearing, making within 15 HP of each other, and driver 1 shifts at 6700-6800 while driver 2 shifts at 7400, driver 2 is going to win at the track. That's got nothing to do with architecture, etc. It's got to to with torque multiplication through the transmission. EVEN IF the higher HP engine is the one shifted at 6700, the above statement will still be true.
Good point V8r. There's average power production on a dyno sheet which I think everyone understands - but average torque at the tire is also extremely important.
Each shift offers ~ 30% less torque at the tire than the gear before. That is a huge difference.
Better yet - you then take the engine that revs to 7400 and switch rear end gears from 3.42's to 3.90's. Due to the extra RPM the mph at redline in each gear stays the same but the torque at the tire has shot up by 14% through the entire rev range. You also get through the "sluggish rectangle port midrange" and into your powerband sooner.