Ran a couple of models on some of the cams above, it'll only let me graph 6 runs at once. This was based upon my prior 347 LS1, Fast 90 LSX intake, ARH 1.75" headers and PRC 5.3L heads. I intentionally cropped off the HP/TQ numbers just to look at the deltas, and I only changed valve events and lift (if provided) so it doesn't take into account ramps, dwell over the nose, asymmetry, etc. Of course you always want to match the cam to the head design to maximize the results but all I wanted to see was how the VE's altered the graph.



Outside of Patrick's RR cam, I like the deltas of the 5/43/47/1 and 3/44/53/2. The cam I used with my 347 was a 227/235 110+2 .645/.650 using LSK lobes... I'd never use LSK lobes in a HPDE/RR car due to the ramps.

I'm not convinced the model of PatG's cam falling off so drastically after 6000RPM isn't exaggerated... but could anything be done to PatG's RR VE's so the HP curve after 6000RPM carried a little flatter until 6500RPM like the other cams without changing too much elsewhere?

 

wow now this is the kinda tech I love. numbers never lie vs "i love my cam" and "it feels awesome" suggestions.
while my colorblindness and lack of knowing what the heck im looking at hold me from learning much, but im anxioius to see you guys discuss the comparo and see what I can pick up.
im getting close to D-day for decision time on my cam as the short block will be finished being built in 2 weeks, and ill need to have cam picked and in hand.

out of curiousity what were the cam specs on the two cams you liked the "deltas" on? (5/43/47/1 and 3/44/53/2)

yeah id definatly never want those .645/.650 lift, jeez. id be sweating bullets about valve springs on every straight away. hoping to stick around the .610ish range that I have now. origonaly was gonna go down to a 600 or so but im slowely creeping up my comfort zone. but 645 would be way out of the question. it sounds like your test motor was very similar to my current and new setup. any other info I could give you that would help your simulator? I recently filled out the 3 page tick cam questionnaire.

HUGE thanks Jim for taking the time to run all those! very cool of ya.

 

Jim, I tend to see overlap helping to carry power past peak due to (I assume) the added scavenging of the chamber at high rpm. I would need to re-read that thread, but I thought I remembered that cam carrying surprisingly well for its size.

 

The 224/228 110 +0 from the "Torque coming out of my ears" thread did carry well. 2-42-44-4 did have added scavenging, enough to overcome the late EVO of 44. The 223/223 110+2 with it's 3.5-39.5-43.5- -.5 lacks that scavenging and goes limp after 6k in Jim's simulator.

STANG KILLA SS 2, the 5-43-47-1 was the 228/228 I suggested. Now my arm is sore from patting myself on the back. The Jim sim also makes me think the 225/225 won't carry. Now you may be asking yourself, "If overlap makes more power why would Jim consider a cam with -13 overlap" ? I think the answer is throttle response. Someone in the other thread said, " Too much power in drag racing, you spin your tires. Too much power in road racing, you spin your car ". I could handle some throttle lag from off-idle to 1500 rpm. The question in my mind is, "How much overlap can I run and have throttle response from 2000 rpm and up " ? Does compression help throttle response ?

 

BTW, STANG KILLA SS 2, did you get a VE calculator like Darth_V8r suggested ? The two Wallace calculators I linked to on the first page of this thread are web based and work well enough. The Excel spreadsheet from Piano Prodigy does much more and is the one I use the most. You can get it here :
https://ls1tech.com/forums/generatio...sier-than.html

To see if you have to fly-cut your pistons for the cam you selected, the P to V calculator speedtigger linked to works very well. Get that here :
https://ls1tech.com/forums/generatio...alculator.html

 

I'm in the middle of modeling something for my LS3 at the moment, it won't be done by the time I leave for work. If there are any other's you want me to model & compare just let me know and I can start on them this evening; the data needed is in the 'Cam Specs' sheet of the "Engine Analyzer Pro testing" Excel workbook link in my signature.

A separate Excel link for Compression calcs is in my sig also. The reverse DCR calculator requires macros, and I've had problems in the past getting that feature to work (even after enabling macros) when downloading it from Dropbox, although it works on my local version of the file; YMMV. This version translates duration/lsa to VEs only; I have a later local build which also does it the opposite way. This sheet was built around PianoProdigy's original work.

I have that PtV calculator also, maybe I'll try to integrate it with my Compression Calculator workbook to reduce the redundant data entry.

 

going back to the first page for a bit about the +3 LSA on the SNS2
(and keeping in mind Ive never installed a cam)
I assume theres a dot or mark or something that you line up the cam with the crank or something when installing?

with the +3 of the SNS2 do you have to rotate the cam 3 degrees when you install it? ie off straight up/lined up? ie is this whats refered to as "degreeing" a cam?
or is the SNS2 installed exactly the same as the others that just have a single LSA number?

 

It's actually really easy. The advance is already ground into the cam. The cam gear will only go on one way. Line up the dots on the timing set and you're set right. I always recommend renting a degree kit to verify, but 95+% of the time, if the dots are lined up, the cam is installed as intended.

 

As I alluded to before, this is only a model... it's certainly dependent upon entering the most accurate data as can be provided for the entire longblock as well as proper implementation by the software developers. Many don't believe in these products and I respect their opinions because people would rather put $500 towards a known proven combination instead of putting it towards simulators which aren't proven to reflect real world results.

Sorry about the colors, all I can do is change the background color of the graph, that won't help comparing the curves. I never looked to see if the calculated data is exportable.

5/43/47/1: 228/228 109/113 (or 111+2) assuming symmetrical lobes, overlap 6
3/44/53/2: 227/235 110.5/115.5 (or 113+2.5) assuming symmetrical lobes, overlap 5

 

Gonna have some real world results (hopefully) soon on a similar setup to what you guys have been talking here. Also building a road race 6.0 motor, topped with aftermarket as cast heads with hollow valves and a 226/230 114+3 middle of the road cam.

Valve events are
IVO 2* BTDC
IVC 44* ABDC
EVO 52* BBDC
EVC -2* ATDC
0 overlap at 0.050

Hoping this peaks around 6400 or so so I can rev to 6800. And with 11.5 compression should have a nice torque band while being easy to drive and on the valvetrain (sub .600 lift and smooth Cammotion lobes).

Will let you know how it feels after I tune and break it in.

 

Guys I have not read the linked threads yet so maybe this is covered there but I have not seen mention of the effect of engine size which I believe has a significant impact on cam size, timing, etc. Anyone care to comment? Great thread!

 

Torque coming out of my ears thread: https://ls1tech.com/forums/generatio...am-change.html
Matching dyno thread: https://ls1tech.com/forums/dynamomet...o-results.html

My takeaways from the first thread:
---begin---
IVC: Near 41-44 to match manifold runner length, peak around 6200/6300. Increase it by a few degrees for it to carry past 6300.
EVO: In 40's, numerically lower better for torque. 44 long power stroke (good for torque); 48 medium power stroke; 52 shorter power stroke (softer on torque)
Overlap bias ((ivo-evc)/2): negative indicates intake bias (carrys past peak power very well); positive indicates exhaust bias (falls off past peak power much quicker)

So to get it to carry better past peak HP:
* Increase IVC by a few degrees
* EVC needs to be greater than IVO to get the overlap to be intake biased
---end---

My understanding regarding larger displacement is that the motor will typically have a larger cylinder bore and usually bigger valves, so it moves more air. A cam that causes a 346ci to breathe deep,due to lift,duration and valve opening and closing points, won't fill a larger displacement equally or the same volumetric efficiency won't be met due to the larger motor's bore & valve size. Of course there are many variables to deal with when talking about optimum cam timing for any given motor but it's all about what the cam will do to 'effeciently' fill the chambers. A larger motors natural torque increase at low RPM's will likely more than offset the torque loss caused by a cam designed for higher RPMs. So you would need to adjust the valve events to match the needs of the increase CFM demand.

 

it would appear the two your referring to are the top two on my list
the TSP 228R and the Tick SNS2 (although i would probly go with the mild version of the SNS2, how much would this change its graph/delta/events?)
which would be your choice? (anyone)

also the TSP 228R has your choice of LSA. you give 111+2, so would i order the 111 or 113?

i wouldnt mind seeing how the Titan 4 stacks up to these two above. its an extra $50
Duration at .050 - 227/232
Lift with 1.7 - .612/.595
Lobe separation 113
Intake center line 109

 

Here's a model containing my prior two discussed favorites from this thread (5/43/47/1 & 3/44/53/2) but also containing Redtan's 2/44/52/-2 and Patrick's Torque cam (2/42/44/4). The former two are quite similar and the latter two are quite similar.



Performance wise on this model, I like Pat's just slightly over Red's, and either over the first two. Pat's has less residual exhaust overall, but RedTan's short circuits just a little less around peak torque. Pat and RedTan's also have less propensity to knock above 4500RPM than the other pair. Pat's has a little higher intake vacuum than RedTan's above 5600RPM to redline. RedTan's idle vacuum is expected to be in the upper 15's, while Pat's is expected to be in the upper 14's. If I was spending a lot of time on the highway in 6th gear at low RPM's cruising (below 1500 RPM) I'd opt for Pat's due to the bump in torque and slightly better BSFC, but it might require a little more TLC on the idle tuning.

Something that irks me about EAP is that the cam valve event calculation iterations are based upon duration and centerlines, not the specific VE's. So I can't run a model with specific ranges for each event. I requested an enhancement and they said they'd add it to the list and expect it to be done in 1-2 years

 

Definitely stick to the cams in this group^. There is not a loser in the bunch. The wider lobe center angle cams like these generally exhibit a wider flatter power curve which you will find beneficial in road racing.

 

Below is what I was considering to match with some ported LS3 heads, except modeled in my old 347 LS1 block above... -1/41/53/-1 or 220/232 114+3, 2* overlap, no bias. Smoothes out the dip near 3000RPM and sacrifices a little at each end.



The cams suggested by Geoff, Kip & Martin are all pretty similar... +/- a few HP above 6200RPM, +/- a few ft/lb below 5000RPM. Geoff's has less residual exhaust below 2000RPM. Other than that nothing of note on the modeling. I'd go with whomever makes you the most comfortable.

Cams Suggested to me:
226/234 .604"/.604" LSA113+3 (Geoff @ engpwrsys): 3/43/53/1, 4* overlap, exhaust bias
224/230 .612/.604 LSA114 Int. c/l 111 (Kip @ cammotion): 1/43/52/-2, 1* overlap, exhaust bias
227/235 .618/.600 LSA112.5+3 (Martin @ Tick): 3/44/52/3, 6* overlap, no bias

Those three against the 220/232 114+3:

 

I don't put much stock in those simulators. They were fun to play with, but I never use them to make real world decisions.

 

Look into a grandam cup cam. It was made for road racing.

 

If you go for the TSP 228R make sure you get the NEW design with the .600" lobes and the 8620 Callies Carbocore, not the older design with the XE-R lobes.
In case your not getting this Valve Event thing, let me go into more detail.
Lets take Geoff's EPS 226/234 113+3 as an example. 3/43/53/1 are the events. Intake valve is open to .050" lift 3 degrees before top dead center . Intake valve is .050" before closed at 43 degrees after bottom dead center. Exhaust valve is open .050" at 53 degrees before bottom dead center. Exhaust valve is .050" before closed at 1 degree after top dead center. The overlap on this cam is called "Exhaust Biased" because more of it is on the exhaust stroke, before TDC. On Pat G's 224/228 110 +0 the VE's are 2/42/44/4 so it's Intake Biased, more overlap after TDC on the intake stroke.
The LSA (lobe separation angle) on Geoff's cam is 113 degrees, it's ground in and can not be changed. The advance is +3, also ground in but it can be changed by you when your installing if you have adjustable timing gears. Changing your advance does NOT change your overlap, it just changes where the overlap occurs ( intake biased or exhaust biased). You can calculate a cam's overlap. Add the intake and exhaust durations and divide by 4. subtract the LSA from that number and double the result. 226 + 234 = 460. 460 divided by 4 is 115. 115 - 113 =2. 2 doubled is 4. That cam has 4 degrees of overlap.
What you get for the extra $50 is this: the cam is ground on a 8620 core instead of a 1060 core. The 8620 is a tougher material. After it's ground, the lobes are polished to get rid of a whining sound some cams have. Instead of a cam card saying what the finished size should be, you get a Cam Dr. report with a actual measurement of the finished cam.

 

JimMueller, would you compare a couple of cams for me ?

228/230 112 +4 Jegs TrickFlow
224/230 111 +1 PREDATOR_Z suggested for me

Also, I'm curious what PipeMax says about my headers. I have a Y pipe like you but here are the measurements of my headers: Spoolin FD headers 1 7/8" primary 1=34 3=29 5= 27 7=22 2=34 4=30 6=24 8=22 for a 27.75" average length. 18* Merge Collector from mid-merge to V-band = 6"
RX7 ORY , V-Band to FlowMaster 4" merge 22.5" , 4" mid pipe 30" , 4" to 3.5" transition 4.5" , 3.5" to muffler 23" , OBX muffler 18" , 4.5" Muffler tip 8"