What to Do Next - Big Duration on a 115??
Thread Starter
TECH Senior Member
iTrader: (7)
Joined: Nov 2001
Posts: 9,491
Likes: 1
From: Bethesda, MD
What to Do Next - Big Duration on a 115?? Well its probably cam changing time, the 232/236 114 is a little big for me, at least if I stay with stock cubes. I like its top end pull, but it needs a 1000 rpm idle and I can't get rid of the occasional surge in 1300 - 1400 rpm range.
The previous cam was a 224/224 114 which had decent manners (900 rpm idle and no surge at 1200), but I'm trying to stretch a little more power out and use a 900 - 950 rpm idle with no surge at 1300 so I was thinking of a comp XE-R:
228/228 115 +4
or
226/230 115 +4
I'm pretty sure the 228/228 114 has been run sucessfully and probably would meet my drivability criteria. However, I'm somewhat curious to see what a 115 LSA would do, if anything. Could I drop the idle back another 25 - 50 rpm? Does the increasse in LSA defeat the gains from increasing duration?
So what happens when you combine a lot of duration with a high LSA?
<small>[ December 12, 2002, 08:15 PM: Message edited by: Ragtop 99 ]</small>
The previous cam was a 224/224 114 which had decent manners (900 rpm idle and no surge at 1200), but I'm trying to stretch a little more power out and use a 900 - 950 rpm idle with no surge at 1300 so I was thinking of a comp XE-R:
228/228 115 +4
or
226/230 115 +4
I'm pretty sure the 228/228 114 has been run sucessfully and probably would meet my drivability criteria. However, I'm somewhat curious to see what a 115 LSA would do, if anything. Could I drop the idle back another 25 - 50 rpm? Does the increasse in LSA defeat the gains from increasing duration?
So what happens when you combine a lot of duration with a high LSA?
<small>[ December 12, 2002, 08:15 PM: Message edited by: Ragtop 99 ]</small>
TECH Fanatic
Joined: Aug 2002
Posts: 1,566
Likes: 0
From: Objects in mirror no longer matter.
Re: What to Do Next - Big Duration on a 115?? </font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Ragtop 99:
<strong>So what happens when you combine a lot of duration with a high LSA?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">You shift your car really high.
<strong>So what happens when you combine a lot of duration with a high LSA?</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">You shift your car really high.
Launching!
Joined: Nov 2001
Posts: 294
Likes: 0
From: Dallas, TX
Re: What to Do Next - Big Duration on a 115?? Joel, I'm by no means an expert...but here goes
could you try something along the lines of the TR 227/224 114 ( with maybe more lift for your heads )
it should idle well, make good power to 6400, and let u shift no later than 6800 or so....
-Alex
could you try something along the lines of the TR 227/224 114 ( with maybe more lift for your heads )
it should idle well, make good power to 6400, and let u shift no later than 6800 or so....
-Alex
TECH Apprentice
Joined: Aug 2002
Posts: 331
Likes: 0
From: Gambrills, MD
Re: What to Do Next - Big Duration on a 115?? What happens when you widen the LSA by 1 degree is that you lose 2 degrees of valve overlap. This means the car will idle slightly better, and throttle response at lower RPMs will be slightly smoother.
Theoretically, the wider LSA will make the power band start slightly earlier, and it will maintain power slightly longer after peak HP is reached. Peak HP and TQ will be slightly lower. However, with only one degree of difference in LSA, the net effect will be very minimal.
Theoretically, the wider LSA will make the power band start slightly earlier, and it will maintain power slightly longer after peak HP is reached. Peak HP and TQ will be slightly lower. However, with only one degree of difference in LSA, the net effect will be very minimal.
Thread Starter
TECH Senior Member
iTrader: (7)
Joined: Nov 2001
Posts: 9,491
Likes: 1
From: Bethesda, MD
Re: What to Do Next - Big Duration on a 115?? I don't have a problem shifting high. I have an ARE shortblock and use 6800 with my current cam. As long as I get a nice wide torque curve, I'm fine with shifting high. I need to be able to have good torque (not peak) by 4000 rpm and my shift extension is well over 5000 rpm, so high end power is ok. I know that shifting the power curve down would be best for maximum ET, but I also enjoy spinning the motor up in 2nd & 3rd gear on country roads when I can't get to the track.
Vice: what rpm or speed is your buddy using for lock-up?
Alex, I think ARE big valve heads like mine respond better to single or traditional split patterns.
Vice: what rpm or speed is your buddy using for lock-up?
Alex, I think ARE big valve heads like mine respond better to single or traditional split patterns.
Re: What to Do Next - Big Duration on a 115?? Joel - I think the 228/228 114 LSA cam would be a great choice. I'm running our 228/228 on a 111 LSA in my A4, and I LOVE it. My peak HP is right at 6,400, and it carries it out to 6,600 before starting to drop off. My old 224/224 112 LSA cam only had two degrees of advance ground in, and it peaked at 6,550 RPM. My current 228/228 has 3 degrees ground in, FYI. You won't have a problem with targeting a 900-950 RPM idle with this cam, especially on a 114 LSA. I have mine idling at 850 RPM. <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" /> The only time I have any surging issues is when the car is cold. Once it is up to temp, I do not have any problems whatsoever.
You'll pick up some drivability over the cam you have now, and you'll still be able to wind the engine out without it running out of breath. I think it will work out well for you. Besides, now is the time to buy a cam since we're having a cam sale! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Trevor
You'll pick up some drivability over the cam you have now, and you'll still be able to wind the engine out without it running out of breath. I think it will work out well for you. Besides, now is the time to buy a cam since we're having a cam sale! <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />
Trevor
__________________
Trending Topics
Re: What to Do Next - Big Duration on a 115?? That cam is going to rock for you! First, it will have a smooth idle for a 228 cam (wide LSA & fast XE-R lobes). I do not think this cam will have as high of a power peak as some will say. With an intake closing point of 45 degrees ABDC, you are in the ideal range of making kickass power with a 346. You should make peak power at about 6200-6300 and it will carry nicely past 6800. Although you might give up 5 rwhp peak power vs going with a narrower LSA cam, you will be 5 rwhp stronger at 5000 rpms and 6500 rpms than a 112 LSA cam. Basically, you will give up a little peak power, but have a broader, flatter power curve. Just the ticket for an automatic and a Pro Thruster converter. I say well done!
__________________
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
2013 Corvette Grand Sport A6 LME forged 416, Greg Good ported TFS 255 LS3 heads, 222/242 .629"/.604" 121LSA Pat G blower cam, ARH 1 7/8" headers, ESC Novi 1500 Supercharger w/8 rib direct drive conversion, 747rwhp/709rwtq on 93 octane, 801rwhp/735rwtq on race fuel, 10.1 @ 147.25mph 1/4 mile, 174.7mph Half Mile.
2016 Corvette Z51 M7 Magnuson Heartbeat 2300 supercharger, TSP LT headers, Pat G tuned, 667rwhp, 662rwtq, 191mph TX Mile.
2009.5 Pontiac G8 GT 6.0L, A6, AFR 230v2 heads. 506rwhp/442rwtq. 11.413 @ 121.29mph 1/4 mile, 168.7mph TX Mile
2000 Pewter Ram Air Trans Am M6 heads/cam 508 rwhp/445 rwtq SAE, 183.092 TX Mile
2022 Cadillac Escalade 6.2L A10 S&B CAI, Corsa catback.
2023 Corvette 3LT Z51 soon to be modified.
Custom LSX tuning in person or via email press here.
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Re: What to Do Next - Big Duration on a 115?? I had a 228/228//111 back in 2000 and it was fun and with tuning it ran okay.
I think a 228//228//115 would idle like a B1 but you'd have to advance it for sure to keep the peak from being too high.
I think a 228//228//115 would idle like a B1 but you'd have to advance it for sure to keep the peak from being too high.
Re: What to Do Next - Big Duration on a 115?? Ask Terry Burger about his MMS 229 cam. He had one in his stock cubed engine runnin 10s. Its a single pattern cam with .578" lift and 230 duration at .050" lift with a 114 LSA.
Thread Starter
TECH Senior Member
iTrader: (7)
Joined: Nov 2001
Posts: 9,491
Likes: 1
From: Bethesda, MD
Re: What to Do Next - Big Duration on a 115?? PSJ: 4 degrees of advance is the plan.
Dug: The MMS cam is what made me think that it would work. It runs close to 230 duration on a 114, so my guess is a 228 on a 115 would perform close, but have slightly better drivability.
Dug: The MMS cam is what made me think that it would work. It runs close to 230 duration on a 114, so my guess is a 228 on a 115 would perform close, but have slightly better drivability.
Re: What to Do Next - Big Duration on a 115?? Rag
Those are the correct numbers for the the mms229 cam. I bought one used and those were the numbers on the cam card. I havent installed it yet so I cant tell you anything about the idle quality. Some say its smooth some say its rough. Probably a matter of tuning and idle speed. I have a M6 so it doesnt really matter. If youre interested, MMS has a dyno of that cam on their website. Its in a z06 corvette.
Good Luck!
<small>[ December 13, 2002, 09:19 PM: Message edited by: dug ]</small>
Those are the correct numbers for the the mms229 cam. I bought one used and those were the numbers on the cam card. I havent installed it yet so I cant tell you anything about the idle quality. Some say its smooth some say its rough. Probably a matter of tuning and idle speed. I have a M6 so it doesnt really matter. If youre interested, MMS has a dyno of that cam on their website. Its in a z06 corvette.
Good Luck!
<small>[ December 13, 2002, 09:19 PM: Message edited by: dug ]</small>