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| What duration cams for automatic set-up? http://4g61t.org/forum/viewtopic.php?f=6&t=35496 |
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| Author: | CSM Shaun [ Sun Oct 23, 2011 1:33 am ] |
| Post subject: | What duration cams for automatic set-up? |
Do any of you guys have any idea what duration cams the fast auto guys are running? I have BC 272s and BC 280s but no idea which set I should be using in my Galant. It is a 2.0l engine but will be automatic. Turbo choice right now is a twin-scroll MHI 25g(certain to be laggy). I can rationalize using the 280s to get more top end, but I am concerned that the automatic set-up will not allow the engine to spin fast enough to make use of the power-band that the 280s will offer. On the other hand, I can rationalize using the 272s to have a bit better mid-range but plenty of top end but I am not sure if the 272s will give me enough top end to make use of the 25g. I will also say that whatever set of cams is not used in the Galant will be used in my 1.6l Scummit with Tonus' old PTE 56 trim turbo. I am more worried about the Galant having the ideal set-up than the Scummit though. |
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| Author: | CaptainTonus [ Sun Oct 23, 2011 1:00 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Anything Brian Crower is complete garbage. Sell both those sets of cams and pick up some FP2's. Done, and done. |
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| Author: | fastvtgsx [ Sun Oct 23, 2011 8:49 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Funny, I've heard some interesting things about the FP2's as well as the BC stuff. I'd think 272's would be fine for you, think back before anyone used 280's and were making plenty of power on the 272's. I think too many people jump to 280s way before they really need them. |
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| Author: | CSM Shaun [ Sun Oct 23, 2011 9:27 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Both of these sets of cams were bought at big time discounts. I will have to check on the specs of the FP2s and see how they compare to the 280s or the 272s. |
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| Author: | CaptainTonus [ Sun Oct 23, 2011 10:01 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Quote: I will have to check on the specs of the FP2s and see how they compare to the 280s or the 272s.
I used to run the BC 280's on my car. The idle was awful, and the bottom-end was also awful. The mid-range and top-end were decent, but the rest of my setup had issues. I swapped to FP2's and noticed HUGE gains in the low-end and still had plenty of power up top. There are numerous examples of people on Tuners swapping from BC 280's for FP2's and actually GAINING power up top, even though FP2's have way way less duration and lift. With automatic and a 2.0L, you're gonna want as much low-end as possible. I'd stick with a mild cam. Either FP2's or maybe HKS 264's or 272's. Kelford is making some exceptionally nice cams, as well as GSC. There are a ton of options.
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| Author: | CSM Shaun [ Sun Oct 23, 2011 10:11 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Then I will be running the BC 272s in the Galant for the time being and keep an eye open for some Kelfords or FPs. I dunno how the 1.6 in the Scummit is gonna like the 280s, but they will certainly be better than the stockers. |
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| Author: | Crackerman [ Sun Oct 23, 2011 11:09 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
with an auto you want to build torque. its the only way to make car driveable. 264's would be my choice. and can support well over 500 hp. more than enough for low 11's or 10s all day long. |
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| Author: | CSM Shaun [ Mon Oct 24, 2011 9:26 am ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Understood but I don't think 264s will offer enough top end. I am not actively searching for new cams, I am trying to decide which set of the two sets that I currently have should be used. If the car were to be a manual with a twin-disc clutch (as was my previous plan for the car) then no doubt I would be using the 280s. But for now I will be rocking 272s until a nice set of Kelfords or FPs roll my way. |
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| Author: | CaptainTonus [ Mon Oct 24, 2011 9:47 am ] |
| Post subject: | Re: What duration cams for automatic set-up? |
FP2's are only like 25x-something duration, but have more lift than HKS 272's, at least on the exhaust cam, and my car made peak power at 8,000rpm on the dyno with those cams and a FP3065. Granted, I have a pretty aggressive port-job on my head, but still, smaller duration cams don't necessarily mean you'll have less top-end. |
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| Author: | CSM Shaun [ Mon Oct 24, 2011 11:13 am ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Also understood. I am not a cam expert but I do understand the power band is influenced by more than just the duration by other factors such as: ramp-up rate, over-lap and lift. The head I will be using has port work, 1mm oversized valves and new Manley springs with titanium retainers. Using the BC 272s or other comparable(and probably better) cams the mid should be good with plenty of top end as you dudes have discussed. |
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| Author: | Mechacode [ Mon Oct 24, 2011 7:42 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
If you simply want advice between the two you have, go with the 272's. With 1mm oversize, you'll flow plenty of air to make power with them without all the crappy qualities of 280's. |
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| Author: | CSM Shaun [ Mon Oct 24, 2011 9:52 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Awesome, thank you boys. |
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| Author: | boostfreak [ Tue Oct 25, 2011 6:43 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Quote: Then I will be running the BC 272s in the Galant for the time being and keep an eye open for some Kelfords or FPs. I dunno how the 1.6 in the Scummit is gonna like the 280s, but they will certainly be better than the stockers.
280's is about the worst cam you could use on a 1.6 |
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| Author: | Enter [ Tue Oct 25, 2011 7:35 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
A buddy of mine had FP2 cams in his auto 2.0L summit and it was very street worthy imo. |
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| Author: | CSM Shaun [ Tue Oct 25, 2011 8:54 pm ] |
| Post subject: | Re: What duration cams for automatic set-up? |
Quote: 280's is about the worst cam you could use on a 1.6
I would need a good reason as to why this is true. The 1.6l has absolutely no bottom end and the mid range is a joke; all due to the 75mm stroke and massive pistons. For a 1.6l the 4g61 is very over-square; Honda's d15b and the 4g15 both have a stroke around 80mm for a point of reference. I think 280s and a set of springs and retainers would make this car far better as it would give a power band of something like 4500rpm to 9000rpm rather than the current 4000rpm to 7500rpm with a sheet metal intake manifold from JMF or some other reputable company.Quote: A buddy of mine had FP2 cams in his auto 2.0L summit and it was very street worthy imo.
That is good to know. I am watching for cheap FPs or Kelfords but would rather just stick with what I have now and spend the money elsewhere. I appreciate the good words about the FPs though.
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