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Old 10-12-2019, 02:57 PM   #101
runslikeapenguin
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Quote:
Originally Posted by shoestring View Post
Please elaborate. Was this measured in an axis that is not in the same plane as the valve stem? If so, then yes, there would be disparities.
I was measuring the crank angle at max lift on intake #1. My dial indicator was at a slight angle but i was only looking for the crank angle at max lift.


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Originally Posted by shoestring View Post
I've measured this at both 0.040" mill and ~0.100" mill and it is extremely close to 1 degree per 0.010". Also, the math backs it up.
This could be due to the IPD cam gear problems you suggested.
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Old 10-12-2019, 08:19 PM   #102
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Yeah, that old style IPD gear is junk. At least the one we measured is. Glad they redesigned it. I'm wondering if there was a redesign in the grind of their turbo cam around the same time? I seem to remember their site mentioning a 110* lobe separation on the cam and I see that is now gone. Perhaps we measured a different version of the cam? The one you had measured by Delta looks really awesome for a street turbo car whereas ours looks like a weird inbetweener grind for NA/Turbo...
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Old 10-14-2019, 02:44 PM   #103
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Originally Posted by redblockpowered View Post
ours looks like a weird inbetweener grind for NA/Turbo...
I think that is how it was originally sold and advertised? But maybe not. I did run it in my NA car once and wasn't too excited about the experience because the dyno curve looked almost exactly like my A cam curve, if I remember correctly.
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Old 10-14-2019, 03:10 PM   #104
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Maybe we can measure enough of these and find a production split. Or ask IPD.
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Old 10-17-2019, 11:49 AM   #105
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Alright, so I sent an email to IPD, and here's the reply I got:

"The designs have been the same for awhile, the supplier has changed now that they are billet and not cast."

Hmm...
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Old 10-17-2019, 01:56 PM   #106
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Hmm, indeed... I guess, did you just ask if there was a production change or did you ask if someone has actually verified that their timing marks are correct? Haha
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Old 10-17-2019, 02:08 PM   #107
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I asked if there were any design revisions, but I suppose that's a fair question too.
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Old 10-20-2019, 09:53 AM   #108
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K13 Turbo added.
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Old 10-21-2019, 02:41 PM   #109
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Quote:
Originally Posted by shoestring View Post
K13 Turbo added.


We're running the non-turbo version in the General Leif, which should be the same aside from the 106° LSA instead of 114°. It looks like there's a large chunk of duration to gain by using tight valve clearances with this camshaft! It has much more off seat duration than even the OC352 "rally" cam, but at .025" and .035" of lift the rally cam has more duration. After that, they're equal for a little bit before the K13 takes over again having fatter and taller lobes.

The factory H cam has a smidge more duration than the K13 between .025"-.250", then after .350" the K13 has more(as well as .5mm more peak lift on the intake lobe and 1mm more peak lift on the exhaust lobe).

Maybe this OC352 rally cam isn't nearly as aggressive as you thought, Shoestring... I've run the K13 in my car and still run it LH2.4 without issues.

Maybe I should adjust the intake valves on the General Leif a bit tighter to give us some more top end.

Last edited by klr142; 10-21-2019 at 04:30 PM..
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Old 10-21-2019, 04:00 PM   #110
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On this K13 you can see the transition between the ramps and the flanks on the dial indicator. It was pretty crazy.
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Old 10-21-2019, 04:23 PM   #111
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It was definitely a lot more aggressive than I expected. Side note: In the process of measuring this one up we tried to find the lift at which ENEM publishes their duration, but we were unsuccessful. Seems like it's something somewhat arbitrary, 0.8mm or the like.
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Old 10-21-2019, 04:24 PM   #112
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I wonder how much difference it makes power wise to play with the lash because of it! It seems like it's definitely worth trying if there was a way to measure power. I don't know that I would want to pay for dyno time to adjust all the valves, though. Well, if I only do the 4 intakes, maybe it wouldn't take too long...

It's a "280°" camshaft according to their notes, and based on that info, indeed it seems like it's measured somewhere likely around 0.8mm. Odd! Here's the info I posted earlier:
Quote:
Originally Posted by klr142 View Post
I'd like to see something that outperforms the H/K cam noticeably without giving up a lot around idle and under 2000-2500rpm, just because it's a more modern camshaft design. Why doesn't anyone make this?!

My ENEM K13 might be close, as it's 12.5mm lift and "280°" duration. Here's more information on that. [EDIT: I'd say it's pretty close!]


ENEM K13 measurements(RSI had it measured):

intake lift .490" / exhaust lift .489"
intake duration at .020" = 288° / exhaust duration at .020" = 284.2° - Don't know if these numbers are after taking up valve lash.
intake duration at .050" = 240.2° / exhaust duration at .050" = 239.6°

K13 as advertised by ENEM:

280/280/105/107/12.5/12.5/2.8/2.4/ 0.40:
In. duration 280° / Ex. duration 280º
In. centerline? 105° / Ex. centerline? 107°
In. lift 12.5mm / Ex. lift 12.5mm
In. lift at TDC? 2.8mm / Ex. lift at TDC? 2.4mm
Valve clearance or lash 0.40mm
Inlet: Open 35 BTDC - Close 65 ATDC / Exhaust: Close 33 ATDC -Open 67 BBDC.
LSA = 106 and 28 degrees of overlap @ .050
The duration at .020" as measured by RSI shows a little less duration than what you measured at .020 here. The difference between the intake and exhaust durations are pretty significant at low lift for you as well where I think the lobes are supposed to be the same.

Last edited by klr142; 10-21-2019 at 05:32 PM..
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Old 10-21-2019, 05:46 PM   #113
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I have another cam in my possession that may be an "RSI Stage 3 NA cam", or may be a copy of the ENEM C2 camshaft that measured at .550" lift, 264°/264° duration and 336° at .012" according to the same place that measured my K13 as 240°/240° at .050" and 288°/284° at .020", for what it's worth.

That seems like a big jump at .050" and explains why it's a performance beast! I'd like to get it back in a motor sometime to play with but I'm still scared to run lash caps under the buckets in addition to shims on top... When we ran this cam last(still on LH2.4!), the engine through a rod and had a piston slam the combustion chamber. One of the lash caps was missing which may have been the or maybe not because I know we were running excessive ignition timing?!
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Old 10-25-2019, 01:29 AM   #114
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For reference and what it's worth, I confirmed with Reine at Agap.se that their measurements are taken at zero lash: http://www.agap.se/Utrustning-2.html.
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Old 10-25-2019, 11:39 AM   #115
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Quote:
Originally Posted by klr142 View Post
For reference and what it's worth, I confirmed with Reine at Agap.se that their measurements are taken at zero lash: http://www.agap.se/Utrustning-2.html.
This is good to know, because there's pretty good specs here. What's up with these cams, though? Do you buy the lobe profiles and then set the separation value you want, or what, because I don't see actual camshafts listed, just lobes.

If it is, I like it.
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Old 10-25-2019, 08:25 PM   #116
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Correct! You pick LSA(or talk to them about your specs and they help*) and profile. It's an extra charge for a dual profile camshaft, but sometimes that is ideal to help with torque. Erland Cox likes to recommend that in NA builds, I think he may have mentioned running around 10° less duration and .5mm less lift on the exhaust side.

Last edited by klr142; 11-05-2019 at 07:00 PM..
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Old 10-25-2019, 09:38 PM   #117
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Quote:
Originally Posted by klr142 View Post
I have another cam in my possession that may be an "RSI Stage 3 NA cam", or may be a copy of the ENEM C2 camshaft that measured at .550" lift, 264°/264° duration and 336° at .012" according to the same place that measured my K13 as 240°/240° at .050" and 288°/284° at .020", for what it's worth.

That seems like a big jump at .050" and explains why it's a performance beast! I'd like to get it back in a motor sometime to play with but I'm still scared to run lash caps under the buckets in addition to shims on top... When we ran this cam last(still on LH2.4!), the engine through a rod and had a piston slam the combustion chamber. One of the lash caps was missing which may have been the or maybe not because I know we were running excessive ignition timing?!
I have a C2 on the bench that I need to send in. When I send my core cams back to josh, I'll cart that with me and send it up
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Old 11-05-2019, 07:02 PM   #118
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Looking at AGAP's offerings and my notes on the ENEM C2, their R33-265-14.0 is pretty close in rough measurement, it seems.

I'm waiting to hear back on what he thinks about running lash caps under the buckets in addition to the standard shims in the buckets. People say it's ok, other people say it's sketchy, and I've seen one lash cap disappear(or at least, I'm certain it was there initially) in an engine of ours that blew up, so I think it's sketch as well... But, I'd really like to try that camshaft out!!!
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Old 11-06-2019, 02:46 PM   #119
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And here is Peter's measurement of the Enem C2 previously posted.

http://forums.turbobricks.com/showpo...2&postcount=72
Attached Images
File Type: jpg Enem C2 cam spec 2.jpg (186.1 KB, 39 views)

Last edited by klr142; 11-06-2019 at 02:52 PM..
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Old 11-06-2019, 03:50 PM   #120
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Dang
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Old 11-07-2019, 12:09 PM   #121
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Me:
Quote:
I do have one more question for you. I have a camshaft available to me that has a smaller base circle than stock by about 2mm that I am considering running. In your experience, is it safe to run lash caps and shims in the buckets at the same time? The camshaft’s profile is similar to your R33-264-14.0 from the specifications, so it’s pretty aggressive. I do have valve springs set up for 14mm of lift with stainless steel 46/38mm valves, but I am still cautious to run both shims and lash caps at the same time. The last engine this camshaft was in blew a rod through the block and I couldn’t find one of the lash caps after disassembly.

Am I worried about nothing and it’s common for people to run both, or should I set the clearances a different way and just use shims or lash caps to set the clearance?
Reine from AGAP:
Quote:
I do not feel it is a problem to use lash caps, the ones I sell sits 2.5 mm down on the valve stem, so for those to come loose it need to be valve float with at least 2.5 mm, if that is happening it would just be a matter of time for something else to brake if there are no lash caps to come loose. The engines that I hear of with these kind of problems is if there are very aggressive, engine speed limiter or launch controls.
Maybe I'll try this out...
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Old 11-08-2019, 04:36 PM   #122
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Grip it n rip it
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