Author Topic: 305??  (Read 6537 times)

Offline 09jjtierney

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305??
« on: December 16, 2014, 06:44:24 AM »
I have a 305 crate motor with less than 20k. Wanting to do some upgrades to get more power, but could a 305 really be wort it or should I just swap for something bigger?

Offline Captkaos

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Re: 305??
« Reply #1 on: December 16, 2014, 03:26:48 PM »
What are you wanting to achieve, how much power?  What is the usage?

Chris Lucas
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Offline 09jjtierney

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Re: 305??
« Reply #2 on: December 16, 2014, 07:26:08 PM »
Its a daily driver for now and one day hope to be a show quality truck.I'm not looking for enough power to race or anything just want to improve enough to get on the the highway and keep up with the other cars. Right now a Prius could get up to speed quicker and pass me if I had a head start haha. And that doesn't settle well.. I know my way around a motor and how everything works but as far as blueprinting an improvement plan I don't know where to start.

Offline VileZambonie

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Re: 305??
« Reply #3 on: December 16, 2014, 07:28:41 PM »
Sounds like you need to start at the back end. What is your final drive ratio? What trans do you have?
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Offline 09jjtierney

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Re: 305??
« Reply #4 on: December 16, 2014, 07:43:46 PM »
I have 700r4 and I don't know what final drive is

Offline VileZambonie

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Re: 305??
« Reply #5 on: December 16, 2014, 07:47:04 PM »
Well that's where you should start. Tell us more about your truck
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Offline 09jjtierney

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Re: 305??
« Reply #6 on: December 16, 2014, 07:59:23 PM »
Ill tell you anything you want to know. To be honest I don't know how to find out what the final drive ratio is. I know I just had the 700r4 rebuilt <2000 miles ago. Motor is stock crate motor from advance auto I believe.  4 barrel Edelbrock that I can't ever seem to get adjusted quite right. Rear end is stock from what I can tell.

Offline VileZambonie

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Re: 305??
« Reply #7 on: December 16, 2014, 08:04:27 PM »
Year, make, model?
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Offline 09jjtierney

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Re: 305??
« Reply #8 on: December 16, 2014, 08:09:34 PM »
1985 Chevy c20 custom deluxe. And I don't know that it makes a difference on specs but originally it was a fire truck

Offline 09jjtierney

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Re: 305??
« Reply #9 on: December 16, 2014, 08:11:05 PM »
Fleetside standard cab long bed 2wd

Offline VileZambonie

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Re: 305??
« Reply #10 on: December 16, 2014, 08:12:59 PM »
check the glove box to see if the spid label is there. If so see if it lists the rear axle ratio or code
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Offline gwcrim

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Re: 305??
« Reply #11 on: December 16, 2014, 08:42:09 PM »
A 305 is a small motor with small valves.  Other than a 4 barrel and headers, you'd be better off spending money on a good 350 (or more.)

I changed my rear gears from 2.7 to 3.73 and it didn't accelerate any  better at all.  A 305 isn't a performance engine.

Offline 09jjtierney

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Re: 305??
« Reply #12 on: December 16, 2014, 09:31:27 PM »
Sticker say 3.23 and option code is gu5

Offline flips87c30

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Re: 305??
« Reply #13 on: December 17, 2014, 08:05:11 AM »
My 92 Chevy has a 305 with a 700r4 and I love it granted it is TBI but it has plenty of power.
87 v30 duelly dump truck 454, th400, np205, dana 60/14 bolt, warn hubs, gmt800 mirrors and LEDs all around the bed.

Offline VileZambonie

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Re: 305??
« Reply #14 on: December 17, 2014, 07:18:28 PM »
What size tires are you running?

I changed my rear gears from 2.7 to 3.73 and it didn't accelerate any  better at all.  A 305 isn't a performance engine.

Are you sure you didn't put the 2.73 back in?  :P

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                         /  _ _ _\_
              ⌠ŻŻŻŻŻ'   [☼===☼]
              `()_);-;()_)--o--)_)

74 GMC, 75 K5, 84 GMC, 85 K20, 86 k20, 79 K10