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Discussion Starter · #1 ·
I just recently noticed something odd about my engine when it idles. After listening behind the car for some time it sounds like durnig idle the rythem of the exhaust tone changes from time to time. It goes from a lopy muscle car sound to a less consistant less lopy sound. It just changes its rythem, I dont get why or how it could be doing this, I mean the firing order cant change so how could the rythem of the exhaust change?
 

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You have the same cam as me and mine does that to. It goes from a uniform lope like a harley in sync then it i will get choppy and be out of sync. Most of that is due to the higher overlap with our cam. For a moment in the cycling of the engine the intake and exhaust valves are open the same time. This creates the lope and due to the fact we are 6 cylinders this causes for more uneven exhaust pulses. The V8 will actually do
this less do to the fact the time between the next exhaust stroke the more cylinders the less Harley effect the less cylinders the more Harley effect till you get to 2 cylinders and you have a harley which can lope about one exhaust stroke every half a second at idle

I have been talking to RGR and he has developed cams with much less overlap with increased HP
 

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Danger Dude said:
You have the same cam as me and mine does that to. It goes from a uniform lope like a harley in sync then it i will get choppy and be out of sync. Most of that is due to the higher overlap with our cam. For a moment in the cycling of the engine the intake and exhaust valves are open the same time. This creates the lope and due to the fact we are 6 cylinders this causes for more uneven exhaust pulses. The V8 will actually do
this less do to the fact the time between the next exhaust stroke the more cylinders the less Harley effect the less cylinders the more Harley effect till you get to 2 cylinders and you have a harley which can lope about one exhaust stroke every half a second at idle

I have been talking to RGR and he has developed cams with much less overlap with increased HP
These cams are actually available NOW, right away.
For what we talked about Corey, I could actually make a
substantially larger cam that is smoother. It would have
more duration @ .050" and less actual overlap. Only to
a point tho... but a cam with similar "lope" would be bigger
than the existing grind, and same LCA's. I need to work up
a trade in program for people wanting to upgrade...
 

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RGR said:
These cams are actually available NOW, right away.
For what we talked about Corey, I could actually make a
substantially larger cam that is smoother. It would have
more duration @ .050" and less actual overlap. Only to
a point tho... but a cam with similar "lope" would be bigger
than the existing grind, and same LCA's. I need to work up
a trade in program for people wanting to upgrade...

EXCUSEEEEEEEEEEEEE MEEEEEEEEEEEEEEEEEEE

I meant to say he HAS developed cams with much less overlap with increased HP

HAHHAHAHAHHA ;) :D
 

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^^^ NutCase ^^^

:D :lol: :D

Thanx for that clarification Corey!
I actually did a few with the old list,
but one was lucky to get 2 lobes of the same .050" that
were distinctly different. Actually, I have one guy now
that is using the same basic .050" durations as you guys
and in a heavy auto tranny T-Bird, he says the power just
blows him away and he doesn't even have the tune yet!

His 215 cam vs. the old 215 cam:

NEW 215 lobe......Old 215 Lobe
215*...................215....................050 duration
.576"...................495"...................total lift w.1.73's
He is running .599" lift with the 1.8's, that adds 4* more total
valve action on average. I like his grind because it is better matched
than the old 215/225 cams, that was my first SC spec grind for big
boost, I'd use less exhaust duration for NA and street SC setups.
You all got my old SC grind, but it was not sold or specced by me,
lots of people pick these up used and while it is a good cam it is not
the best for everyone. Even For José, who the cam was originally
specced out for, I would change up a few items now, considering
the grind availability and the fact that I am a better cam guy now.
That cam was done nearly 6 years ago and we have better springs
and better cam lobes both, plus a better understanding of what these
engines need for the given application.

JUST IN CASE anyone still thinks I spec cams for RPM, think again.
I only spec cams for RDMotorsport, and my RGR-Alumni that need upgrades.
I did not train anyone in cam specs and will not divulge my specs.
But I can get the econo grinds still, if someone can't see the wisdom
in getting the better lobes for a few bucks more. I'll do the best I can
with the old spec lobes. It's just like trying to plow with a horse instead of a tractor :D
 

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Discussion Starter · #6 ·
Okay, this makes since, glad to know it! I spliced in my new TPS from Rob and it seems to have helped alot with the idle. It still doesnt idle down imediately but I guess thats normal.
Its weird cause my idle seems more consistant now as far as the lope goes... :confused: weird.
 

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Discussion Starter · #8 ·
RGR said:
Maybe Bro. Corey could idle smoother if his TPS was adjusted.
:confused: ya think Bro?
Hmm, maybe, it seems like my idle is way more consistant now. I will be listening to it to see for sure...
One thing that dissapoints me a bit is the fact that it still takes a good six seconds to idle down. Its better, but still not normal. Maybe its my splicing technique or something...
 

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No I found what my problems were I think. I installed my BV head and Matching lower today. What I found was startling

1. I had 2 bent push rods. One was bent in 2 places.
2. The cylinder that had the worse bent rod also had the tip of the 19# injector sort of melted. After careful surgery. I repaired it and it is spraying just fine.


While I was at it I reconnected my PCV valve and vaccum line form the drivers valve cover to the CAI. I was tired of smelling oil whrn the AC or the heat was on.

UI have not started it yet because as I was putting on the Radiator plastic drain plug it cracked so it sits until tomorrow ARGGHHHHHH
 

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Discussion Starter · #10 ·
So I take it you had replacement pushrods availible? How did you valves look in your old heads? Man, bent pushrods cant be good for performance. Im sure you will be a much happier person with your BV heads and straight pushrods.

Keep us updated!
 

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Outstanding, glad to hear you FINALLY got those heads on there. You know I've been trying to get to work on this intake i'm trying to design, it should help out quite a bit if I can ever find the materials for it. That's my biggest problem at the moment.
 

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:hammer: :hammer: :hammer:

Dang, that is bad news! You needed something, better
springs or shimmed PR's... Let's make sure this one is
right b4 you crank it! I can call ya DD. LMK
 

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Discussion Starter · #16 ·
Danger Dude said:
She is running great. 75% of the shaking is gone. Idles better. Well get to a dyno ASAP
Bad out dude, you should post some pics of them bent pushrods.
 

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Discussion Starter · #20 ·
My gosh dude, thats bent alright. I wonder how it got like that? Were the rockers too tight or something?
 
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