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Discussion Starter · #1 ·
Has anyone else noticed the advertised duration and lift for the vtec lobes are the same for the Toda Spec B's and N2's?
 

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Yep. Which is why the N2's are a better choice than the Spec B's since they also retain VTC.
 

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Discussion Starter · #3 ·
I don't see why the spec b's would have a problem with vtc? Yes, the primary and secondary lobes are bigger than the N2's, but they're not bigger than the vtec lobes. Plus if you could clay the motor and find out exactly how far you could go, then you could use the k-pro to keep it from advancing the cam too far, right?
 

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JTSmith said:
I don't see why the spec b's would have a problem with vtc? Yes, the primary and secondary lobes are bigger than the N2's, but they're not bigger than the vtec lobes. Plus if you could clay the motor and find out exactly how far you could go, then you could use the k-pro to keep it from advancing the cam too far, right?
I'll admit it's strange.

The primary and secondary lobes on the N2's have the same lift and duration as the Spec A's, the VTEC lobe on the N2's have the same lift and duration as the Spec B's.

I agree that valve-piston interference would be most likely to come on the VTEC lobe.

To be honest, I have no idea why the Spec B's kill VTC. I think that Toda used the "old rules" (i.e. B-series) when they made the Spec B's and didn't want to mess with restricting VTC. So, they killed it. Later, they learned about VTC and released the N2 cams. But of course, that's just my speculation. No one really knows but them I guess.

Anyway, I'm sure that the K-Pro could be used to retain VTC on the Spec B's, but the question is would the extra lift on the primary and secondary lobes be worth it?
 

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We've installed much larger cams than any of the available Toda cams, AND retain VTC. With ~13.5mm lift - max cam advance is limited to 30 degrees with stock valves and pistons as tested on a K20A (11.5:1).

-Ron
 

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edo said:
We've installed much larger cams than any of the available Toda cams, AND retain VTC. With ~13.5mm lift - max cam advance is limited to 30 degrees with stock valves and pistons as tested on a K20A (11.5:1).

-Ron
Didn't the Hytech setup use a 30 degree limit? I also seem to remember Doug saying that only 25 degrees advance is needed for maximum torque on the high cam.
 

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Discussion Starter · #7 ·
edo said:
We've installed much larger cams than any of the available Toda cams, AND retain VTC. With ~13.5mm lift - max cam advance is limited to 30 degrees with stock valves and pistons as tested on a K20A (11.5:1).

-Ron
Ok do you mean the cam angle w/ the k-pro can only go as high as 30 or you can advance the cam 30 crankshaft degrees?

Also, do you have any specs on the cams you used b/c you can't really say(except for the exact cam you tested ;) ) "with 13.5mm max cam advance is limited to 30 degrees" b/c it will depend on the duration of the cam.
 

· pete
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edo said:
We've installed much larger cams than any of the available Toda cams, AND retain VTC. With ~13.5mm lift - max cam advance is limited to 30 degrees with stock valves and pistons as tested on a K20A (11.5:1).

-Ron
Ron i hope i have missed anything on the forum but are there any updates on the cams you were working on?
 

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JTSmith said:
Ok do you mean the cam angle w/ the k-pro can only go as high as 30 or you can advance the cam 30 crankshaft degrees?

Also, do you have any specs on the cams you used b/c you can't really say(except for the exact cam you tested ;) ) "with 13.5mm max cam advance is limited to 30 degrees" b/c it will depend on the duration of the cam.
You are correct, I purposefully did not mention the duration of this particular cam. It does have way more duration than any Toda application on the market. I cannot share any specifics for duration at the valve. We tested P/V and V/V throughout the entire cycle. This is how we ascertained the physical 30 degree cam advance max (not crankshaft degrees). Anything more would caust V/V contact. There is slightly more room for lift before P/V contact occurs.

This very agressive profile is a 10K+ application. The small lobes alone are roughly the size of the stock Type-S high cam lobe. These made power all the way to 7500rpm and necessitated a very late VTEC crossover to the high cam. Essentially, we ran out of rpms. We know that the stock rods don't like much over 9k, so we did not even bother trying to find peak power with this set of cams.

-Ron
 

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Discussion Starter · #10 ·
edo said:
You are correct, I purposefully did not mention the duration of this particular cam. It does have way more duration than any Toda application on the market. I cannot share any specifics for duration at the valve. We tested P/V and V/V throughout the entire cycle. This is how we ascertained the physical 30 degree cam advance max (not crankshaft degrees). Anything more would caust V/V contact. There is slightly more room for lift before P/V contact occurs.

This very agressive profile is a 10K+ application. The small lobes alone are roughly the size of the stock Type-S high cam lobe. These made power all the way to 7500rpm and necessitated a very late VTEC crossover to the high cam. Essentially, we ran out of rpms. We know that the stock rods don't like much over 9k, so we did not even bother trying to find peak power with this set of cams.

-Ron

I was thinking about this earlier and I got confused, but how can you get 30 degrees of advance when the k-pro has 50 degrees of movement, 25 advance, 25 retard?

Who can I contact about getting cams? (you can pm if you don't want to post)
 

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It starts out at zero (0) or fully retarded, then you have up to 50 physical degrees available for cam advance on the stock VTC internal sprocket.

The cam I was referring to isn't available.

-Ron
 

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edo said:
It starts out at zero (0) or fully retarded, then you have up to 50 physical degrees available for cam advance on the stock VTC internal sprocket.

The cam I was referring to isn't available.

-Ron
hey edo...can you help me with some info retaining to the K24 head..
http://forums.clubrsx.com/showthread.php?p=2652670#post2652670
I know you must get alot of questions....but can you answer my simple questons.. :dontknow: :thumbsup:
 

· big magic bumpsticks soon
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edo said:
You are correct, I purposefully did not mention the duration of this particular cam. It does have way more duration than any Toda application on the market. I cannot share any specifics for duration at the valve. We tested P/V and V/V throughout the entire cycle. This is how we ascertained the physical 30 degree cam advance max (not crankshaft degrees). Anything more would caust V/V contact. There is slightly more room for lift before P/V contact occurs.

This very agressive profile is a 10K+ application. The small lobes alone are roughly the size of the stock Type-S high cam lobe. These made power all the way to 7500rpm and necessitated a very late VTEC crossover to the high cam. Essentially, we ran out of rpms. We know that the stock rods don't like much over 9k, so we did not even bother trying to find peak power with this set of cams.

-Ron

what do you mean when you say 10k+ application?
 

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A 10k rpm plus application, in other words the cams were so agressive that the peak power, assuming the intake and exhaust systems were free flowing enough and the compression was high enough, would be made above 10k rpms. Correct me if i`m wrong though.
 

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Discussion Starter · #16 ·
I seriously doubt you would make peak power above 10k. Just b/c you turn 10k or higher does not mean your power will peak that high.
 

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I dont know is if that was adressed at me but i was answering Diggs question. What a 10k plus application was. From the way edo made it sound, they could not reach the peak power, even revving over 9k. With 13.5mm lift and "a lot more duration" then toda cams i`m inclined to think this is what he meant. We`ll just have to wait for him to chime in and clarify.
 
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