Another annoying "best cam for my 305" post
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Car: 83 bird
Engine: 305/383
Transmission: WC T5
Axle/Gears: 3:42
Another annoying "best cam for my 305" post
Just trying to wake my 305 up a bit. Car is not daily driven or track driven... just a weekend fun machine.
Engine in my car is an 84 LG4 with Edelbrock Performer intake and unknown-size headers & 3" exhaust. T5 car with 3.42 gears.
I do plan on upgrading the valve springs when I do the cam too.
Just looking to get the most power out of this I can with a cam upgrade.
What are the stock heads good till? That might help me choose.
I was looking at these two cams, but now after some research I'm finding they might be too aggressive as the stock specs are 202/206 .403/.415
Lunati Voodoo 10120703 - 268/276 .489/.504 https://www.summitracing.com/parts/lun-10120703
Comp Cams 12-242-2 - 268/280 .477/.480 https://www.summitracing.com/parts/cca-12-242-2
So now I'm looking at this one here: https://www.summitracing.com/parts/sum-1103; 288/298 .444/.466
Suggestions? I'm sure sofa or five7kid will know
Engine in my car is an 84 LG4 with Edelbrock Performer intake and unknown-size headers & 3" exhaust. T5 car with 3.42 gears.
I do plan on upgrading the valve springs when I do the cam too.
Just looking to get the most power out of this I can with a cam upgrade.
What are the stock heads good till? That might help me choose.
I was looking at these two cams, but now after some research I'm finding they might be too aggressive as the stock specs are 202/206 .403/.415
Lunati Voodoo 10120703 - 268/276 .489/.504 https://www.summitracing.com/parts/lun-10120703
Comp Cams 12-242-2 - 268/280 .477/.480 https://www.summitracing.com/parts/cca-12-242-2
So now I'm looking at this one here: https://www.summitracing.com/parts/sum-1103; 288/298 .444/.466
Suggestions? I'm sure sofa or five7kid will know
Last edited by aaron7; 12-06-2020 at 06:44 AM.
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Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: Another annoying "best cam for my 305" post
While it's usually a 'don't spend a dime on a 305' a good cam choice on an LG4 is a 12-256-4
https://www.compcams.com/xtreme-ener...all-block.html
used it and it was good but mine did seem to be a bit noisey.
https://www.compcams.com/xtreme-ener...all-block.html
used it and it was good but mine did seem to be a bit noisey.
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Re: Another annoying "best cam for my 305" post
Both of those cams are WWWWWWWWWWAAAAAAAAAAAAAAAYYYYYYYYYYYY too much for LG4. They need more compression. The 1103 suffers from the inadequate compression problem in the LG4 as well; its EXTREMELY LAZY ramps cause considerable bleed-off of cylinder pressure at low RPMs, and consequently will give very soggy results with the gears you have.
For the early ones like yours, with just over 8:1, the Comp XE256 is a very good option. For the L69 and later LG4 with the 9.x compression, the XE262 works well.
I'd strongly recommend the XE256 or something in that same range from another mfr; the Lunati Voodoo series would be a good place to look, if they have one. If they do, its advertised duration will be acoupla degrees lower than the Comp, like maybe 253 or 254.
For that matter, even the cheeeeeeeeeep Summit 1102 works reasonably well in the LG4, if all you want is "improvement" and you're not looking for the absolute optimum.
You need valve springs no matter what cam you pick. For anything in the range we're talking about here, the LS6 springs with Comp 787 retainers and all the matching hardware, set up at 1.75 - 1.80", will handle it. 28-12713265-16 GM High Performance LS .550" Lift Springs (Replaced LS6) (texas-speed.com)
For the early ones like yours, with just over 8:1, the Comp XE256 is a very good option. For the L69 and later LG4 with the 9.x compression, the XE262 works well.
I'd strongly recommend the XE256 or something in that same range from another mfr; the Lunati Voodoo series would be a good place to look, if they have one. If they do, its advertised duration will be acoupla degrees lower than the Comp, like maybe 253 or 254.
For that matter, even the cheeeeeeeeeep Summit 1102 works reasonably well in the LG4, if all you want is "improvement" and you're not looking for the absolute optimum.
You need valve springs no matter what cam you pick. For anything in the range we're talking about here, the LS6 springs with Comp 787 retainers and all the matching hardware, set up at 1.75 - 1.80", will handle it. 28-12713265-16 GM High Performance LS .550" Lift Springs (Replaced LS6) (texas-speed.com)
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Car: 90 Formula / T-tops
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Re: Another annoying "best cam for my 305" post
mind if I hop on and ask what cam would be good for 1990 LB9? Been thinking of replacing lifters and while in there maybe even having the heads ported along with an Edlebrock intake and SLP runners. just a dream for now, really wanting to get back on changing rear drums to disks and putting in some better gears.
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Car: 92 Firebird, 77 Trans Am SE, 86 Z28
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Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: Another annoying "best cam for my 305" post
mind if I hop on and ask what cam would be good for 1990 LB9? Been thinking of replacing lifters and while in there maybe even having the heads ported along with an Edlebrock intake and SLP runners. just a dream for now, really wanting to get back on changing rear drums to disks and putting in some better gears.
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Re: Another annoying "best cam for my 305" post
LB9 needs a roller cam specifically and carefully targeted to the unique requirements of TPI.
I agree w/ the 501 recommendation. That's what that series was made for. Another somewhat similar one is the 302 grind. Both will "work" with stock tunes but will benefit GREATLY from tuning. The 500 or 301 grinds will deliver less improvement but can probably get by without tuning. Needless to say, either will require springs; the LS6 ones mentioned above will work for these as well. Lifter replacement not really required unless they're bad or wore out in some way, but always a good idea in high mileage motors of course.
I agree w/ the 501 recommendation. That's what that series was made for. Another somewhat similar one is the 302 grind. Both will "work" with stock tunes but will benefit GREATLY from tuning. The 500 or 301 grinds will deliver less improvement but can probably get by without tuning. Needless to say, either will require springs; the LS6 ones mentioned above will work for these as well. Lifter replacement not really required unless they're bad or wore out in some way, but always a good idea in high mileage motors of course.
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Car: 90 Formula / T-tops
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Re: Another annoying "best cam for my 305" post
thanks guys. have the EBL P4 setup, so I have the ability to "learn" to tune. just looking for more street pep, not a 1/4 mile runner. lifters sat in one position for 25 years while in storage, so I'm thinking replacing them could be an improvement, even if subtle. can change the shift point with the EBL P4. not sure if the rest of the motor can handle higher RPMS but will to do what it takes to get there, including springs/rockers. 65K on motor
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Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: Another annoying "best cam for my 305" post
thanks guys. have the EBL P4 setup, so I have the ability to "learn" to tune. just looking for more street pep, not a 1/4 mile runner. lifters sat in one position for 25 years while in storage, so I'm thinking replacing them could be an improvement, even if subtle. can change the shift point with the EBL P4. not sure if the rest of the motor can handle higher RPMS but will to do what it takes to get there, including springs/rockers. 65K on motor
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Car: 90 Formula / T-tops
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Re: Another annoying "best cam for my 305" post
the rollers are probably fine. I doubt sitting harmed them. You can disassemble and clean them too. Springs are all you'd really need. Factory rockers would be fine though full rollers are an improvement. Changing the intake is the only thing that'll greatly increase rpm range. The tpi long runner is going to force it pretty close to stock no matter what.
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Car: 92 Firebird, 77 Trans Am SE, 86 Z28
Engine: 5.7 HSR, T/A 6.6, empty
Transmission: T-5, TH350, T-5
Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: Another annoying "best cam for my 305" post
I had the top of the motor off to do valve seals and cleaned up everything during that process. when torquing the rockers, I noticed torque would not old on some of them, as if the lifter was weak and bleeding down. Are you saying a ported SLP runner wont help increase upper rpm range?
A siamesed runner will move the rpm band though not nearly as much as switching to a super ram or hsr for example. What I was trying to say was without changing intake length the rpm won't move much, even if the cam is made for a higher range.
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Re: Another annoying "best cam for my 305" post
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Car: 92 Firebird, 77 Trans Am SE, 86 Z28
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Axle/Gears: 3.08 posi, 3.23 posi, 3.23
Re: Another annoying "best cam for my 305" post
you understand. not all of them did that too me. man, it sure makes it hard to get proper torque.
but your still thinking the 501 cam will offer some benefit over the factory "hot" cam? If I port runners and heads, and get more airflow, won't that allow a little higher RPM range? If not, what does it do?
but your still thinking the 501 cam will offer some benefit over the factory "hot" cam? If I port runners and heads, and get more airflow, won't that allow a little higher RPM range? If not, what does it do?
The larger cam will fill the cylinders more, more air and fuel equals more bang. Ported runners, base and heads will give more air. The runner length will be a bigger decider of rpm range.
In other words, the cam may be able to make more power and work well in a higher rpm range but the intake runner length will be what determines the actual range the engine works at.
Last edited by aliceempire; 12-07-2020 at 11:36 AM.
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Re: Another annoying "best cam for my 305" post
If I recall, the factory manual specified a procedure for tightening the rocker arms that involved torque. but I may not be recalling correctly. its been a while. maybe after I got them adjusted, they came out of adjustment due to bleed down and that is what I am recalling.
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Re: Another annoying "best cam for my 305" post
If I recall, the factory manual specified a procedure for tightening the rocker arms that involved torque. but I may not be recalling correctly. its been a while. maybe after I got them adjusted, they came out of adjustment due to bleed down and that is what I am recalling.
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