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Old 12-08-2010, 12:43 AM   #1
dash13
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Keeping my I6 250...what to do?

I am keeping my I6 250 and want to know what to do to it. I have changed plugs and wires and replaced the valve cover gasket. Replaced the fuel filter and did an oil change.


What's next?
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Old 12-08-2010, 01:09 AM   #2
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Re: Keeping my I6 250...what to do?

Here are some pictures of it now.
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Old 12-08-2010, 01:20 AM   #3
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Re: Keeping my I6 250...what to do?

Are you looking to do some modifications? You could look at buying some headers to do dual exhuast and let her breathe a bit better, change from your points setup to an HEI unit. That's all I've done to my 230 yet.
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Old 12-08-2010, 01:29 AM   #4
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Re: Keeping my I6 250...what to do?

Explain the Points to HEI and why one would change.
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Old 12-08-2010, 01:34 AM   #5
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Re: Keeping my I6 250...what to do?

Definitely get an HEI look for late 70s straight sixes in the junk yard (Novas, Camaros, Malibus, & pickups) or get a new one (Ebay $60-$120). They are 100% more reliable. Dual exhausts sounds great on these motors, and an intake, carb, and cam swap will wake that little guy up too. Check out Clifford Performance if you wanna get hooked and spend all your Christmas money!
http://www.cliffordperformance.net/M...gory_Code=C250
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Old 12-08-2010, 01:37 AM   #6
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Re: Keeping my I6 250...what to do?

1. HEI unit. ignition coil into the distributor cap, eliminating the need for a coil wire and adjusting them. HEI's produces both a hotter and fatter spark', huge HP gains.

2.2 barrel carb intake "more fuel flow"

3. go to pick and pull and get a new model exhaust manafold from a inline 6...maybe out of a truck of the 1980-85. they are 1/2" bigger....its like running a header..and run 2 1/2" mufflerand pipe.
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Old 12-08-2010, 01:39 AM   #7
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Re: Keeping my I6 250...what to do?

HEI is way more reliable and produce a hotter spark. You'll have to probably run an ignition hot 12V to power it up because I think the points coil is low voltage. They are 1 wire hook up and easy tach hook up too. Plus they are a cleaner look than the points set-up.
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Old 12-08-2010, 01:46 AM   #8
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Re: Keeping my I6 250...what to do?

This all sounds great.
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Old 12-08-2010, 01:59 AM   #9
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Re: Keeping my I6 250...what to do?

Keep us updated on what you get done. We all have to stick together cause Inliners are like Mopar Guys ........ Crazy and Outnumbered!
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Old 12-08-2010, 02:14 AM   #10
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Re: Keeping my I6 250...what to do?

I can do that. And I certainly notice that

What kind of gas mileage should I expect once I'm driving my truck?
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Old 12-08-2010, 02:17 AM   #11
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Re: Keeping my I6 250...what to do?

Depends on gearing and trans but don't expect over 16
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Old 12-08-2010, 06:17 AM   #12
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Re: Keeping my I6 250...what to do?

As everyone else said - you have to go electronic. Better starting, more power, easier maintenance, better mileage.

I've pulled off 20 mpg with a 250 before on a steady cruise, but 16-18 is the norm for me.

If it's a '67 250 I usually update to the '68-'72 monojet.

You might want to pop a side cover, pull a lifter and look at the cam lobe. If it looks worn it's not too hard to put a new cam in and it will really wake it back up...
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Old 12-08-2010, 10:59 AM   #13
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Re: Keeping my I6 250...what to do?

Quote:
Originally Posted by ol_skool_chevy View Post
3. go to pick and pull and get a new model exhaust manafold from a inline 6...maybe out of a truck of the 1980-85. they are 1/2" bigger....its like running a header..and run 2 1/2" mufflerand pipe.
Will the 80-85 manifold fit on a mid-sixties 230 L6?

I think GM stopped making the 230s around 1970 or so, and mine needs a new manifold. If a newer and better model out of a bigger L6 would work I'd love to make this change.

Thanks!
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Old 12-08-2010, 03:21 PM   #14
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Re: Keeping my I6 250...what to do?

If it's a '67 250 I usually update to the '68-'72 monojet.

You might want to pop a side cover, pull a lifter and look at the cam lobe. If it looks worn it's not too hard to put a new cam in and it will really wake it back up...[/QUOTE]

Tell me more......
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Old 12-08-2010, 03:27 PM   #15
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Re: Keeping my I6 250...what to do?

Quote:
Originally Posted by camrycurt View Post
Will the 80-85 manifold fit on a mid-sixties 230 L6?

I think GM stopped making the 230s around 1970 or so, and mine needs a new manifold. If a newer and better model out of a bigger L6 would work I'd love to make this change.

Thanks!
The exhaust manafold will fit....I have one
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Old 12-08-2010, 03:40 PM   #16
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Re: Keeping my I6 250...what to do?

For future mods (not just the engine) you can go to power steering (pump mounts are harder to find) and brake booster (you'll need the also harder to find offset air filter set up). Both of these are just things to tinker with but keep you looking for I6 parts. Hoses and wiring are things to go through as well. Everything thats black in the pic is new stuff on mine.
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Old 12-08-2010, 05:20 PM   #17
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Re: Keeping my I6 250...what to do?

Quote:
Originally Posted by dash13 View Post
If it's a '67 250 I usually update to the '68-'72 monojet.

You might want to pop a side cover, pull a lifter and look at the cam lobe. If it looks worn it's not too hard to put a new cam in and it will really wake it back up...
Tell me more...... [/QUOTE]

Well, '68 was when the redesigned monojet was introduced. I've found it easier to work on and it performs well. It's a direct bolt-on so I did that to my '67.

I had a '70 Bel Air with a 250 that was not well maintained. It ran, but didn't have a lot of power. I popped a lifter out and looked at the cam lobe. It was worn way down.

For not much money I got a stock replacement cam from JC Whitney and popped it in. Now the valves opened all the way . Made a noticeable difference in power.
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Old 07-25-2017, 10:14 AM   #18
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Re: Keeping my I6 250...what to do?

i got excited when i saw this picture!! i thought mine was actually road worthy hahaha

i did the petronix system in my distributor. i wanted to keep the look of the coil (the original look)
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Last edited by stevenfromtexas; 07-25-2017 at 10:17 AM. Reason: rotate picture
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Old 07-25-2017, 10:21 AM   #19
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Re: Keeping my I6 250...what to do?

sorry if this is sideways too





Quote:
Originally Posted by dash13 View Post
Here are some pictures of it now.
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Old 07-25-2017, 10:45 AM   #20
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Re: Keeping my I6 250...what to do?

Just an FYI, if you want your photos to upload with the proper orientation, when taking a picture...
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Old 07-25-2017, 10:50 AM   #21
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Re: Keeping my I6 250...what to do?

If you have photos that you have already taken with the home button on the left, top or bottom, they will have to be rotated in a piece of software to correct the issue. Even though the appear to be right-side-up on your phone or computer any vBulletin forum (like this one) will not display them properly.

If you would like to know more about how to correct the orientation of images you've already taken please see this post http://67-72chevytrucks.com/vboard/s...d.php?t=743225
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Old 07-25-2017, 02:47 PM   #22
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Re: Keeping my I6 250...what to do?

In '79 the 250 became known as the 4.1 liter Pulsair with integral intake and totally different exhaust manifold. The manifold (80-85 ?) mentioned would have to be from a 292 and not all 292's. It is larger with 3-bolt outlet, but very hard to find and not worth the effort to change the exhaust system for marginal if any improvement.
If you want to change the exhaust, get tube headers and run dual exhaust all the way back.
That change alone to the engine will still give only marginal improvement. You still have a 8:1 cr and not exactly a performance head.

If you are able to adjust points properly and have a dwell meter, keep the stock distributor. The HEI has two advantages. You don't have to adjust or replace the points every 10,000 miles and it will provide a better spark over 6,000 rpm. OK, three, it will fire old, dirty, misadjusted spark plugs, long after their usable life with a points ignition. A remedy is to check and clean every 10,000 along with the points.

It won't give more power or fuel mileage than a well maintained point ignition.

25 years ago I installed an HEI, because my truck was my daily and only driver. I was driving 60 miles a day for work only and the interval for the points needing attention was more frequent than I had time for.

If you want to make changes that will put a smile on your face and make you want to get behind the wheel, add power steering and AC.
These are notable, worthwhile improvements that give the biggest bang for time and effort.

The next thing is gearing. That can be corrected with new rear gears or depending on the current gears, possibly with an over-drive trans.
Unless that has already been addressed, you're probably driving the slow lanes or side streets. Get the right gears /trans and get out on the highway and enjoy.

The one thing that you haven't been told is that the sky will fall if you don't change the Alt to a Internally regulated Alternator. B.S.

I have AC, HEI, electric fan, elec brake controller, Bluetooth stereo and stock alternator.
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Old 07-25-2017, 08:05 PM   #23
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Re: Keeping my I6 250...what to do?

Quote:
Originally Posted by dash13 View Post
I am keeping my I6 250 and want to know what to do to it. I have changed plugs and wires and replaced the valve cover gasket. Replaced the fuel filter and did an oil change.


What's next?
Has your motor been rebuilt? Sure is clean.
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Old 07-25-2017, 10:33 PM   #24
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Re: Keeping my I6 250...what to do?

Quote:
Originally Posted by cericd View Post
Just an FYI, if you want your photos to upload with the proper orientation, when taking a picture...
thank you very much for the picture advise....several of the pictures were taken before the tips..

thank you again
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Old 07-26-2017, 08:06 AM   #25
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Re: Keeping my I6 250...what to do?

I agree with many posters above. HEI (Pertronix OK, but if a failure, HEI parts available inexpensively anywhere around town same day.) Power Steering. I'm OK with manual brakes, even discs but YMMV.

But the best thing you can do for your 6 cylinder is a T5 transmission from an S10 with a 4.3.

I really like the way a lowered truck rides as well. Drop kit, swaybars and gas shocks and my '69 is a pseudo-sports car.
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