305 wrong cam

[Mmoore031908]

So I am just looking for some suggestions on what can be done cheaply to correct the issue. I have over cammed a 305 and it is dog in the low end. Would it be cheaper to buy rear gears another cam. Im looking for a daily driver not a hotrod so I would prefer not to replace it with a 350 unless it was the most cost effective option.

 

[bucket]

Carb/intake?
Transmission?
Current ratio?
Tire size?

If you don't want to change the cam, I'd change whatever else doesn't fit best in the puzzle. If your rear ratio is steep enough, you may get away with just a converter swap. If you have an auto of course.

What cam is it anyway?

 

[Mmoore031908]

305 LE9/700r4/3.08. With stock converter. It has a summit stage 2 intake with 600 cfm summit carb. 31 10.50 15. The cam is part #SUM-1065 http://m.summitracing.com/parts/sum-1065

 

[bucket]

Well that's not such a bad combo, other than the gearing. But I think the gearing is too tall even with a stock cam. It may sound steep, but a 4:10 ratio would do well with the overdrive trans. Even as it is now, you need to make sure the converter is locking up like it's supposed to. A trans temp gauge would also be a very good idea. A lot of 700r4's have died because nobody was aware they were cooking the fluid.

 

[Mmoore031908]

How would I know if the converter is locking up or not? So really the gears would make the combo much better? In your opinion what would be the most cost effective option to replace gears?

 

[Swims350]

you need better gears and that intake is killing you that stage 2 intake is for 1500-6500 rpm so below 1500rpm it sucks. 305 is best for low end torque. You need better gears if not then you need to change cams to an rv or towing cam more for low end. cost wise if you can't do gears yourself but you can do a cam swap, do cam swap. gears are gonna e $300 for a front and rear set with nothing else, unless you get lucky and find used.

 

[bucket]

The manifold is fine, it's a dual plane. Even if it were a single plane, it wouldn't hurt as much as the tall gearing.

Where is the timing being run at?

 

[Swims350]

no it shouldn't bother it as much as other stuff but it is the wrong rpms range. IMO 3.08's are good for a car not a truck unless it's a 2wd lowrider or something, they should have no place in a 4wd.

 

[Georgeb]

I think a cam change would be a good first option. Then I would consider gears after I tried the different cam. With an overdrive available I would go to 4.10s for gears.

 

[MikeB]

Your manifold would work a lot better on a 350 than a 305, especially a 305 with 3.08 gears. I'd go with a Performer EPS or Weiand Street Warrior manifold along with a cam in the range of 194/204 duration, which is close to the specs of a base 350 cam. Anything more just isn't gonna work in a 305 and 3.08 axle.

Just so happens Crane makes a nice little 305 cam at 194/204 with a 104 LSA. Even with more duration than a stock 305 cam, its 104 LSA will preserve, maybe even increase, cylinder pressure. http://www.summitracing.com/parts/crn-114112

Crane's Description:
Great for 305 engines in cars, light and intermediate trucks with optional gearing. (Consider that 2.56 and 2.73 were common standard ratios in the 70s and 80s.)
Good low and mid-range torque and HP.
800-4400 RPM power band

 

[firebane]

Don't forget with a cam swap you're going to need a lot of stuff.... cam, lifters, rad fluid, oil etc.

Cam change is going to add up pretty quick.