Design a custom cam for me thread
#21
Interesting thoughts guys. I was shifting at 6200. I did not test different shift points. 6200 just sounded and felt right to me. I would like to see it pull hard to a 6500 shift point. The car was dead hooking when flashing the converter from 1800 RPM. I did not look to see what it was flashing to. The 60's were in the high 1.6s. I was thrilled with that. If the car 60' slightly slower, but made up for it in ET hustling out the back door, I would take that trade off. On the street, that is a better situation as this car will never dead hook on the street.
I have to say though, we would not even be having this conversation if the car had more thump at idle. This camshaft reminds me of an old Chevrolet small block Chevy cam we used to call "The 151 Cam" (because of the GM part number). That cam ran fantastic in street cars, but it had one of those idles that was neither here nor there. It did not lope steady and it would not idle totally smooth, so it always just kind of sounded like that car was poorly tuned. Great cam lousy idle.
I have read from a few guys who take the TSP 228 cam and grind it on 110 lobe separation and have great results. That might achieve what I want without making the bottom too soggy. I am not in any hurry to tear into this engine again any time soon, but I would enjoy the cruising experience more with some thump while sitting at a light.
I have to say though, we would not even be having this conversation if the car had more thump at idle. This camshaft reminds me of an old Chevrolet small block Chevy cam we used to call "The 151 Cam" (because of the GM part number). That cam ran fantastic in street cars, but it had one of those idles that was neither here nor there. It did not lope steady and it would not idle totally smooth, so it always just kind of sounded like that car was poorly tuned. Great cam lousy idle.
I have read from a few guys who take the TSP 228 cam and grind it on 110 lobe separation and have great results. That might achieve what I want without making the bottom too soggy. I am not in any hurry to tear into this engine again any time soon, but I would enjoy the cruising experience more with some thump while sitting at a light.
#23
Go bigger duration on your cam like a V2 and your car will be slower at the track. You combo is working well together now, jumping to a low 230s cam will throw that out the window IMO. I wouldn't switch cams at your point just for sound while possibly losing performance.
Last edited by kinglt-1; 08-19-2011 at 12:45 AM.
#24
Maybe Im not understanding your point here, but your last two posts seem conflicting...why would a tr230 be a good choice, if you think a lower 230 duration cam would be slower at the track? Or were you just sayin a tr230 is a good choice for the sound? Not tryin to be a dick at all, perhaps it's my ignorance that needs a better explanation.
#25
Joined: Aug 2007
Posts: 24,241
Likes: 83
From: Turnin' Wrenches Infractions: 005
Well first, I don't particularly care for the V2 or the Futral F14 (which is very similar) for multiple reasons and I never recommend them. However, the TR230 is a 230/224 and comes very highly recommended, idle sounds very good. Some cams seem to work better then others, TR230 is one of them. That's why I recommended it.
#27
#30
I have read from a few guys who take the TSP 228 cam and grind it on 110 lobe separation and have great results. That might achieve what I want without making the bottom too soggy. I am not in any hurry to tear into this engine again any time soon, but I would enjoy the cruising experience more with some thump while sitting at a light.
#32
Overall I don't think there was a bad suggestion in the bunch. I will absolutely consider having Patrick Gs recipe cooked up. It looks like a winner to me. But as many of you have said and a couple of the local race car guys at the speed shop said today: "Your car ran 7.40s in this heat, I wouldn't touch a thing". Everybody is probably right on that, but I just love a bumpin' idle. So, I will rest on it til' winter time and see if I still want to make the change then.
#34
He went just a tad bigger. I stayed a tad smaller because of your converter. But being on a 111 it will bring it on a tad quicker and keep you from shifting as high.
Eps was a no brainer!
I forget.. What was the original cam? Was it specs for your setup or what? Pat g wouldn't have specd that if it wasn't going to go make more power and run better times.
Eps was a no brainer!
I forget.. What was the original cam? Was it specs for your setup or what? Pat g wouldn't have specd that if it wasn't going to go make more power and run better times.
#35
.......Pat G...................STAR
226/230 111+2.......226/236 112+3
IVO.........4.........................4
IVC.........42.......................42
EVO.........48.......................53
EVC.........2.........................3
ECL.........113......................115
OVP.........6.........................7
I'm no cam guru, but looking at these numbers I'm guessing my suggested cam would hold on a little longer up top. Maybe make a few more peak hp numbers?
Overall, most of the cams listed are very similiar and would probably be within 5-10 hp.
Fun game
226/230 111+2.......226/236 112+3
IVO.........4.........................4
IVC.........42.......................42
EVO.........48.......................53
EVC.........2.........................3
ECL.........113......................115
OVP.........6.........................7
I'm no cam guru, but looking at these numbers I'm guessing my suggested cam would hold on a little longer up top. Maybe make a few more peak hp numbers?
Overall, most of the cams listed are very similiar and would probably be within 5-10 hp.
Fun game
#36
It was a fun game indeed STAR. Great suggestion and thanx for playing.
#38
Interesting thing I noticed when comparing the Patrick G recommended Cam to my current grind. It appears that the recommended cam ( EPS 226/230 on 111) actually has less intake duration at .006" than my current cam (XE 222/224). So while the cam has more duration at .050" the seat timing at .006 is actually less than my current Comp XE lobed cam. And while the new recommended EPS grind has 6 degrees of overlap vs. 2 degrees of overlap on my current XE grind, the EPS only has 2 degrees more overlap at the seat timing of .006". This makes me wonder if this cam will lope much harder at all. I will have to put this question to Patrick for his input.
Here are the specs on the new grind:
226/230 .598”/.600” 111LSA +2 advance (with 1.7 ratio rockers)
Comp EPS/EPS lobes 54-000-11 3 bolt cam core
13117R/13118R HR111LSA +2 advance (109 installed intake centerline)
Cam Valve Events 0.006 0.050 0.200
Intake Duration - ID 275 226 148 13117R EPS lobe .598"
Exhaust Duration - ED 279 230 151 13118R EPS lobe .600"
Lobe Center Angle - LSA 111 111 111
Intake Centerline - ICL 109 109 109
Intake Valve opens - IVO 28.5 4 -35 BTDC (- indicates ATDC)
Intake Valve closes - IVC 66.5 42 3 ABDC
Exhaust Valve Opens - EVO 72.5 48 8.5 BBDC
Exhaust Valve Closes - EVC 26.5 2 -37.5 ATDC (- indicates BTDC)
Exhaust Centerline - ECL 113 113 113
Overlap 55 6 -72.5 degrees
Here are the specs on the current grind:
COMP XR275HR-12
222/224 .566/.568 on 112 ICL 110
Valve timing at .006
intake open: 28 BTDC Intake close 68 ABDC
Exhaust open 73 BBDC Exhaust close 25 ATDC
Here are the specs on the new grind:
226/230 .598”/.600” 111LSA +2 advance (with 1.7 ratio rockers)
Comp EPS/EPS lobes 54-000-11 3 bolt cam core
13117R/13118R HR111LSA +2 advance (109 installed intake centerline)
Cam Valve Events 0.006 0.050 0.200
Intake Duration - ID 275 226 148 13117R EPS lobe .598"
Exhaust Duration - ED 279 230 151 13118R EPS lobe .600"
Lobe Center Angle - LSA 111 111 111
Intake Centerline - ICL 109 109 109
Intake Valve opens - IVO 28.5 4 -35 BTDC (- indicates ATDC)
Intake Valve closes - IVC 66.5 42 3 ABDC
Exhaust Valve Opens - EVO 72.5 48 8.5 BBDC
Exhaust Valve Closes - EVC 26.5 2 -37.5 ATDC (- indicates BTDC)
Exhaust Centerline - ECL 113 113 113
Overlap 55 6 -72.5 degrees
Here are the specs on the current grind:
COMP XR275HR-12
222/224 .566/.568 on 112 ICL 110
Valve timing at .006
intake open: 28 BTDC Intake close 68 ABDC
Exhaust open 73 BBDC Exhaust close 25 ATDC
#40
Speedtigger - I have an EPS 226/230 on 113 LSA (2* overlap). When you said something in an earlier post about an in-between cam that would neither lope steady or idle steady, that's what I think about the cam I have. I'm anxious to hear if an additional -2* LSA (4* overlap) will lope like you want it to, since it sounds like we have the same requirements. When I initially talked to Geoff about the cam specs he recommended 226/234-113 but we ended up with a more conservative route - 226/230 (I wanted to err on the conservative side). I've read many times you can live with 5-7* overlap for a DD/street car and that's definitely what I'll be shooting for next time. My biggest question is - should you get more overlap by decreasing LSA (the direction you're heading) or increasing exhaust duration like Geoff suggested? Interesting discussion.