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camshaft questions 305

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Old 04-20-2010, 10:10 PM
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camshaft questions 305

i was wondering what cam you guys are running in your 305's. ill be going carbed so i am not too concerned about tbi tuning. i was told that going over .480 is very bad. any cam suggestions would be great. we run the lt1 style cams right? anyone running LUN-54760LUN ? it was the only cam i saw for lt engines under .480. please let me know if ive got the info wrong i would rather know now than sticking in a cam and breaking stuff. any suggestions?
Old 04-21-2010, 03:55 AM
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Re: camshaft questions 305

The heads are a limiting factor here. I dont think the stock heads would flow well at .480". I would consider a lower lift cam unless upgrading the heads. The cam is a regular small block roller cam.
Old 04-21-2010, 02:26 PM
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Re: camshaft questions 305

I had a .484 .454 lift cam in my 305. If you run 1.5 rockers and get new springs, you can run the LT4 Hot Cam.

one of my friends got some decent power in his 91 TBI firebird with a stock LT1 cam

Crane Power Max 2050 camshaft in my 86
http://www.youtube.com/watch?v=nGTLJ9nS2aI
Old 04-21-2010, 03:30 PM
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Re: camshaft questions 305

I've been pondering this cam and I wonder what other people think. Given the poor intake flow of the LO3 heads, getting near the max lift of .480" seems like a pointless endeavor.
Old 04-21-2010, 07:23 PM
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Re: camshaft questions 305

There is only 1 cam worth buying for an LO3. It's the ram Jet 350 cam. With the 081 heads, I'd spec you a custom COMP hyd. roller.
Old 04-21-2010, 10:19 PM
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Re: camshaft questions 305

Originally Posted by Zepher
I had a .484 .454 lift cam in my 305. If you run 1.5 rockers and get new springs, you can run the LT4 Hot Cam.

one of my friends got some decent power in his 91 TBI firebird with a stock LT1 cam

Crane Power Max 2050 camshaft in my 86
http://www.youtube.com/watch?v=nGTLJ9nS2aI

i was actually told that you couldnt run more than .480 in a recent email from a tbi tuning guy on a 305 due to clearance issues(i asked specifically about the lt4 hot cam). what valve springs are you running? also what size are the stock rocker studs?
Old 04-22-2010, 08:43 AM
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Re: camshaft questions 305

Originally Posted by Atilla the Fun
There is only 1 cam worth buying for an LO3. It's the ram Jet 350 cam. With the 081 heads, I'd spec you a custom COMP hyd. roller.
I'm curious to your reasoning. It doesn't seems to have a lot of intake duration and it has a really tight LSA (109).
Old 04-22-2010, 09:10 AM
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Re: camshaft questions 305

true, but the tight LSA is cancelled out by the short duration, so you still get an awful lot of idle vacuum, so the computer stays happy. And this cam is 196 / 206 duration at 50, versus the LO3's 178 / 194, so it builds more power without kiling low-rpm torque. And these heads don't allow any top end, so any bigger of a cam just kills low rpm torque while giving you nothing in return.
This cam is cheap, you can get it new for around $135. And the lift is more than the LO3, but not enough to cause problems.
It makes a difference you can feel. Easily.
Old 04-22-2010, 09:26 AM
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Re: camshaft questions 305

Originally Posted by Atilla the Fun
It makes a difference you can feel. Easily.
Well compared to the stock 170ish duration at .050 anything is a massive improvement.

So you think a Lunati cam with 209/213 duration at .050 and a 112 LSA would be too much for a LO3 even with the stock, high torque manifold?

http://www.lunatipower.com/Product.aspx?id=2001&gid=261
Old 04-22-2010, 09:56 AM
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Re: camshaft questions 305

Originally Posted by Saabster
Well compared to the stock 170ish duration at .050 anything is a massive improvement.

So you think a Lunati cam with 209/213 duration at .050 and a 112 LSA would be too much for a LO3 even with the stock, high torque manifold?

http://www.lunatipower.com/Product.aspx?id=2001&gid=261
That cam is mild and would work fine.
Old 04-22-2010, 10:09 AM
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Re: camshaft questions 305

the cam I went with was crane cams compucam 2030 or powermax 2030... that was one of two choices I had or was aware of at the time of carrying a nice decal for my California Emission *****...
Old 04-22-2010, 11:36 AM
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Re: camshaft questions 305

Originally Posted by RED86Z28
That cam is mild and would work fine.
Yeah, it'd work fine from 3000 to 4000. But your average HP from 1500 to 4000 wouldn't be as strong, and that cam costs twice as much. Where's the value? Unless you get 081 heads first, there isn't any.
Old 04-22-2010, 11:37 AM
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Re: camshaft questions 305

Originally Posted by Saabster
Well compared to the stock 170ish duration at .050 anything is a massive improvement.

So you think a Lunati cam with 209/213 duration at .050 and a 112 LSA would be too much for a LO3 even with the stock, high torque manifold?

http://www.lunatipower.com/Product.aspx?id=2001&gid=261
the stock manifold isn't even gonna give you more torque, than the Edelbrock Performer TBI, down at 1500 rpm, where the stock converter stalls to. And if you have a stick, and like idling along at 800 rpm, then any larger cam is a big disadvantage. Keep things in proper perspective.
Old 04-22-2010, 11:56 AM
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Re: camshaft questions 305

Originally Posted by Atilla the Fun
Yeah, it'd work fine from 3000 to 4000. But your average HP from 1500 to 4000 wouldn't be as strong, and that cam costs twice as much. Where's the value? Unless you get 081 heads first, there isn't any.
Well I placed the the value in being able to wind it passed 5,000 rpms. How much torque would it lose below 3000 anyway? I would think that the swirl ports would keep the port velocity decent down in the rev range.
Old 04-22-2010, 12:42 PM
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Re: camshaft questions 305

And there's your problem. Forget 5000 rpm with swirl port heads. You can get there pretty well in first gear, it's true, but even with Edelbrock's TBI intake, LT1 cam and Hooker headers, it's still all done at 4800 because of the heads. It's silly to try to get the cam to do the job of the heads. Leave the cam alone for now, and spend your money on 081 heads. It's a cheaper deal anyway.
Old 04-23-2010, 08:18 AM
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Re: camshaft questions 305

I just programmed the Ramjet cam into desktop dyno and it really doesn't like this cam. The torque below 3000 rpms is way down compared to other cams (the Lunati I suggested, a LT1, or LT4 cam). I think the problem is that while the .050 duration is modest, the total duration is actually large, 288/308. Seat to seat that's 30 degrees more overlap than an LT1/LT4 cam.
Old 04-23-2010, 12:12 PM
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Re: camshaft questions 305

Originally Posted by Atilla the Fun
And there's your problem. Forget 5000 rpm with swirl port heads. You can get there pretty well in first gear, it's true, but even with Edelbrock's TBI intake, LT1 cam and Hooker headers, it's still all done at 4800 because of the heads. It's silly to try to get the cam to do the job of the heads. Leave the cam alone for now, and spend your money on 081 heads. It's a cheaper deal anyway.
anyone know where to find 081 heads? ive called a few places here in houston and no one has them. they all say "well thats a hard head to find..." i searched ebay motors and didnt see anything. anyone have a good source for the 081's?
Old 04-23-2010, 12:26 PM
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Re: camshaft questions 305

Get 059 Vortec's instead, they're more better.
Old 04-24-2010, 12:54 AM
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Re: camshaft questions 305

Originally Posted by Saabster
Get 059 Vortec's instead, they're more better.
What he said!

DD2000 looks very nice with the Ramjet cam and vortec heads.
Old 04-24-2010, 06:04 AM
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Re: camshaft questions 305

Originally Posted by bluers91
What he said!

DD2000 looks very nice with the LT4 cam and vortec heads.
Fixed that for ya.
Old 06-14-2012, 07:57 PM
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Re: camshaft questions 305

You read out to be someone who really know their Chevy stuff. Will you tell me what you think of this combo for my l03 in my 91 camaro. I have a ramjet 350 intake manifold (mefi2) model, in the process of getting some 059 or 520 (vortec) casting heads, E-Z efi computer to take over where the mefi2 left off, 1996 lt4 production cam (not HOT cam), and thats where my plan went blank.... Lol. Do you think you could tell me if I'm on the right page? What am I forgetting?
Old 06-14-2012, 08:47 PM
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Re: camshaft questions 305

what about your exhaust?
Old 06-24-2012, 08:25 PM
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Re: camshaft questions 305

Exhaust has went as far as planned. Flowmaster 80 series muffler wit summit shorty headers with no cat. Nothing major
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