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[email protected] JoeCool Performance
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Discussion Starter · #1 ·
So I was reading the cranking compression thread on here and now its making me think again about the cam I chose for my engine. IMO considering the discussion on that thread especially the points made by Monte lead me to believe that the other cam I have on the shelf might be a better choice but I'd like to get everyones opinion on this. First my combo:

349 ci with probe dome pistons that were flycut to run a large cam and dome edges rounded. Compression sits around 12.5 to 1 I haven't checked cranking compression but will when I get back home from south carolina later this weekend.

AfR 205 with 58cc chambers and heads are fully ported( don't have flow numbers)

Parker funnelweb intake fully ported matched to the heads and clover plenum completely removed to accomodate a nitrous plate.

850 dp with annular boosters and a double cross nitrous plate.

Tranny is a Tremec TKO 600 with 4.30 gears. Car weights 3250 with me in it. I'm laying preety heavy nowadays lol.

This is the cam that is installed now and the engine is running but haven't been able to drive it yet thanks to all the snow.

Comp Cams solid roller

Duration
296 in
306 ex at .20

260 in
270 ex at .50

Lobe lift is .420 and .672 lift with 1.6 rockers.
LSA is 109

Second Cam is another solid roller

Duration

313 in
339 ex at.20

279 in
296 ex at.50

Lobe lift
.463 in .754 with 1.6 rockers
.444 ex .723 with 1.6 rockers

LSA is 116

So what do you guys think? I plan on stepping up to a 350 shot taking steps from 200 up. If changing to the second cam is worth it I will tear down and change springs and cam. It should be easier now since I have a beltdrive. Thanks everyone.
 

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That 2nd cam is way too big for that combo!Call bullet!
 

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[email protected] JoeCool Performance
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Discussion Starter · #7 ·
What do you guys think about the combo that makes the second cam too big. Heads? Compression? I've seen 347s make big power with cams as big and even bigger which is why I thought itd be ok. I am by no means an expert though. The heads and intake have had preety extensive work done on them. If I had them taken any further we would have had to install a pushrod tube and have had welding and epoxy work performed. Maybe this thread will give better info about my combo. Thanks for the responses.

http://www.yellowbullet.com/forum/showthread.php?t=308107&highlight=my+winter+upgrades+have+started
 

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depends on how good those 205 flow, as the pics of the heads the ex port looks very small, i had a set of 225 and the port went past the inside bolt holes.
 

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of the 2 cams listed.. first cam gets the nod.... spray the house down... needs good valvetrain... that is alot of slr.. got to bang them gears.. first to second is going come very quick..
 

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[email protected] JoeCool Performance
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Discussion Starter · #10 ·
Yes the exhaust is not as large as I would have liked but im running 1.75 headers so I couldn't go much bigger than that. This like always is a budget build for me cause I'm broke. I don't have any money to buy a different cam so I'm trying to make the best of the parts I have around.
 

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349" and your compression the 1st cam is better out of the 2..... The second cam is way way too big for 349".... And neither have some critical timing events listed for a nitrous cam.... What degree does the exhaust valve open.... That is the absolute most critical timing event for a dedicated nitrous engine.
 

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[email protected] JoeCool Performance
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Discussion Starter · #13 ·
of the 2 cams listed.. first cam gets the nod.... spray the house down... needs good valvetrain... that is alot of slr.. got to bang them gears.. first to second is going come very quick..
And I love bangin them gears! Surprisingly though last year I'm preety sure that I made it past the 60 ft in 1st gear. It felt like I had time before I had to grab second unlike the other 5 speeds I had. 1st is a 2.87 in this tranny. But then again that was with a 225 shot and box stock parts. Pardon my ignorance but what is slr? The more I read and learn stuff here the more I realize my ignorance lol
 

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[email protected] JoeCool Performance
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Discussion Starter · #14 · (Edited)
Also would it help by changing to 1.7 rockers? Would it be worth the expense. That would bring the lift to .714 which is really what the cam was intended for when I spoke with Aaron **** at comp.
 

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[email protected] JoeCool Performance
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Discussion Starter · #17 ·
349" and your compression the 1st cam is better out of the 2..... The second cam is way way too big for 349".... And neither have some critical timing events listed for a nitrous cam.... What degree does the exhaust valve open.... That is the absolute most critical timing event for a dedicated nitrous engine.
I have some more info for the 1st cam. Valve timing @.50
In open 21
Ex open 64
In close 59
Ex close 26

Mark @ Bullet will be my first call I make when the time comes for a custom cam. In the meantime I have to work with what I have. I was under the Impression that headflow data is needed for a custom cam and don't want to spend the $ until I can provide all the possible info they need.
 

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Just for an example I got a recommendation from Bullet for a 13:1 427 with high ports and a 350 shot and the cam had less duration on the intake and 113 LSA.
 
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