250 Inline 6

[Claytona08]

Has anyone ever put some money into their 250 and got decent HP out of them? If so what did you do? I currently have the stock 250 in my truck with the granny 4 speed transmission (I think) . It has the transmission with L, 1, 2, 3 & R. The truck runs great right now so I decided to do everything else (paint, lowering kit, rims & interior) first and then focus on my engine/drive train. My plan all along was to build a mild 350 and switch the truck to an automatic tranny. The more I drive my truck I really enjoy the manual transmission. It's not a daily driver so I don't have to worry with switching gears everyday. Then all of a sudden last night I got to thinking. How cool would it be to have a truck that sounded great when idling, ran real good and had a little bit of "get up and go" (Not something out running every car on the street, just decent power). Only to tell people you had a 250 under the hood. Is there things you can do to these engines to make that happen? It's just a thought.

[Axle]

Define your idea of what decent horsepower is.

The thing is, to get decent horsepower out of it, you'll be spending $$$$. Back in the 80's, (aka my street racing days. And since I tend to look at it from a drag racing perspective) we had a handfull of guys who where diehard straight and slant 6 lovers. While the 6's did get meaner, they didn't stand a chance against the v8's. They would have been dollars ahead if they had left their I6 passion as a decorative peice in their garage and just swapped in a v8 with minor mods. Yes, they had unique rides, but their mouth went faster than their car. =-)

Without looking into it, which I should to be fair, is whats the pricing like for speed parts for a straight 6 these days? Headers still cost 2-3x what a v8 header set cost? Have you got an integrated head i6 or an older separate head/exhaust? Obviously to do anything with the integrated head unit, you'll either be swapping to the older head, or taking a very expensive aftermarket route.

Obviously I look at it from the go-fast side, if all you are after is a bit more pep, then some basics will get you there without putting you in the poor house, but it'll never give you v8 bang for the buck. Yeah, I'm v8 biased. Yes, I have also owned (inherited) a couple I6 powered cars. Utility-yes. Gofast-not quite.

Best thing I can say is figure out what you want to get out of it.
Grab a pencil and paper and work out the cost to do that vs swapping in a v8.

Alex.

[Claytona08]

Originally Posted by Axle

Define your idea of what decent horsepower is.

The thing is, to get decent horsepower out of it, you'll be spending $$$$. Back in the 80's, (aka my street racing days. And since I tend to look at it from a drag racing perspective) we had a handfull of guys who where diehard straight and slant 6 lovers. While the 6's did get meaner, they didn't stand a chance against the v8's. They would have been dollars ahead if they had left their I6 passion as a decorative peice in their garage and just swapped in a v8 with minor mods. Yes, they had unique rides, but their mouth went faster than their car. =-)

Without looking into it, which I should to be fair, is whats the pricing like for speed parts for a straight 6 these days? Headers still cost 2-3x what a v8 header set cost? Have you got an integrated head i6 or an older separate head/exhaust? Obviously to do anything with the integrated head unit, you'll either be swapping to the older head, or taking a very expensive aftermarket route.

Obviously I look at it from the go-fast side, if all you are after is a bit more pep, then some basics will get you there without putting you in the poor house, but it'll never give you v8 bang for the buck. Yeah, I'm v8 biased. Yes, I have also owned (inherited) a couple I6 powered cars. Utility-yes. Gofast-not quite.

Best thing I can say is figure out what you want to get out of it.
Grab a pencil and paper and work out the cost to do that vs swapping in a v8.

Alex.

Thanks for your response. You seem like a wealth of knowledge when it comes to these things. I was thinking maybe 250hp, maybe 300 if possible without breaking the bank. I'm thinking the engine only produces like 130hp now and that's just a guess. I'm not sure what type of head I have or anything. I just know it's the original 4.1L I6 that came in the truck. I'm not wanting something that I can race. Just something I can take out to a cruise and people say "man that thing looks and sounds good, what ya got in it?" and I pop the hood to their amazement of an inline 6. I was thinking it might just be in my best interest to stick to my original plan of going with a 350 but just wanted to weigh my options.

[russellh575]

You might go to one of the other parts of the forum, like the 60-66 section. They might have a little more information since more of their trucks probably have/had 250's. I've been wanting to do an I6 truck for a long time now, as soon as one comes up in my price range I'm getting it.

[cory d]

the guys on stove bolt might have some idea's. L6's are well balanced but they dont have the cubes. but if its just for kicks, go for it

[72freak]

Stovebolt!

[Claytona08]

Originally Posted by cory d

the guys on stove bolt might have some idea's. L6's are well balanced but they dont have the cubes. but if its just for kicks, go for it

Is Stovebolt a forum?

[68Timber]

I was hoping you'd consider hopping up that motor just to be different. Go for max torque instead of hp and you could make a nice street cruiser out of it.

[72freak]

Originally Posted by Claytona08

Is Stovebolt a forum?

http://www.stovebolt.com/ubbthreads/

[obijuan]

i am building a 292 with just a cam, intake, and headers. ought to be a good conversation piece. not looking to knock down ten seconds, but it will definitely be a new animal.

why do ANOTHER v8? blech! your engine bay has so much room for activities! i personally love the sound of the sewing machine under the hood. you can hear the rockers and the carb whine, otherwise i cant even tell my 292 was running. i LOVE the L6 motors. i say get after it, and build a *****in motor. get a second job first.

take a look at this book, its got lots of concepts and how to really fine tune your motor. most of it will probably be way overboard for you, but the information in there is tried and true, and can be considered superior.

[875.3CHEVY]

im a 5.3 sorta person but i got a soft spot for straight sixes.they pull hard if you can keep the carb tightened down.ive had the wheels off the ground but thats cause i had 3 ton in the back.i want to build one with a t10 behind it.granny tranny is useless unless in a dump truck

[TwoFiftyShifter]

300hp on a 250 will be pricey, and tough without a turbo.

You could probably have something like 200hp and 250 or more lb of torque. And that torque would be made at LOW rpms.

[Claytona08]

Originally Posted by BRUISER

I was hoping you'd consider hopping up that motor just to be different. Go for max torque instead of hp and you could make a nice street cruiser out of it.

I'm considering it hard, lol

Originally Posted by 72freak

http://www.stovebolt.com/ubbthreads/

Thanks for the link.

Originally Posted by obijuan

i am building a 292 with just a cam, intake, and headers. ought to be a good conversation piece. not looking to knock down ten seconds, but it will definitely be a new animal.

why do ANOTHER v8? blech! your engine bay has so much room for activities! i personally love the sound of the sewing machine under the hood. you can hear the rockers and the carb whine, otherwise i cant even tell my 292 was running. i LOVE the L6 motors. i say get after it, and build a *****in motor. get a second job first.

take a look at this book, its got lots of concepts and how to really fine tune your motor. most of it will probably be way overboard for you, but the information in there is tried and true, and can be considered superior.

That might be what I do if I decide to build up this engine. Cam, intake, headers and a carb. What book are you referring to?

[Claytona08]

Originally Posted by 875.3CHEVY

im a 5.3 sorta person but i got a soft spot for straight sixes.they pull hard if you can keep the carb tightened down.ive had the wheels off the ground but thats cause i had 3 ton in the back.i want to build one with a t10 behind it.granny tranny is useless unless in a dump truck

What is a t10? Is it a manual tranny?

Originally Posted by TwoFiftyShifter

300hp on a 250 will be pricey, and tough without a turbo.

You could probably have something like 200hp and 250 or more lb of torque. And that torque would be made at LOW rpms.

How much do you think it would cost to build one with a turbo?

[obijuan]

this is the book, sorry! lol
http://www.ebay.com/itm/NEW-Chevrole...item2c7392b703


and it takes one metric crap load to run a turbo.

[INSIDIOUS '86]

Ever heard of lump ports? I didn't look for a price but they are def worth looking into
http://www.12bolt.com/lump_head_info...nder_head_flow

[Claytona08]

Thanks guys for all the help.

[Claytona08]

Originally Posted by INSIDIOUS '86

Ever heard of lump ports? I didn't look for a price but they are def worth looking into
http://www.12bolt.com/lump_head_info...nder_head_flow

Never heard of that. I'll look into it. Thanks

[68Timber]

If this truck were automatic, I'd be all in favor of continuing with the V8 plans. But having the SM465 in the truck with a six, it just kinda begs to stay six.

[Claytona08]

Originally Posted by BRUISER

If this truck were automatic, I'd be all in favor of continuing with the V8 plans. But having the SM465 in the truck with a six, it just kinda begs to stay six.

Yeah I really enjoy cruising around in the truck with the manual transmission. I found this video on YouTube that I'd like the engine to look like if I decided to keep the I6. I wouldn't want a cam as heavy as the one in the video though. Just a mild cam would be good for me. I have a Chevelle that I'll have for when I want to go fast...

Chevy 250 Inline Six - YouTube

[moregrip]

I'm keeping my 250 inline 6 too brother. Nothing crazy. 194 head, Clifford intake, headers, with a Weber 2 barrel carb, stock bottom end.

Looking for a nice DD type setup. Nothing overly finicky.

Maybe......."maybe" some form of FI in the distant future.

[Claytona08]

Originally Posted by moregrip

I'm keeping my 250 inline 6 too brother. Nothing crazy. 194 head, Clifford intake, headers, with a Weber 2 barrel carb, stock bottom end.

Looking for a nice DD type setup. Nothing overly finicky.

Maybe......."maybe" some form of FI in the distant future.

Where did you buy your parts at? Are you running the stock cam?

[moregrip]

Originally Posted by Claytona08

Where did you buy your parts at? Are you running the stock cam?

I bought the carb/intake/headers from Clifford as a package deal, comes with air cleaner and fuel pressure regulator which is nice.

Bought the bare 194 head off ebay.

I plan on running the stock cam at first, then switch to a performance cam in the future.

Have nothing installed yet, so still lots to do

[Claytona08]

Originally Posted by moregrip

I bought the carb/intake/headers from Clifford as a package deal, comes with air cleaner and fuel pressure regulator which is nice.

Bought the bare 194 head off ebay.

I plan on running the stock cam at first, then switch to a performance cam in the future.

Have nothing installed yet, so still lots to do

Thanks man! The more videos I watch and read into this makes me want to keep the I6 even more.

[Jonboy]

Originally Posted by Claytona08

Thanks man! The more videos I watch and read into this makes me want to keep the I6 even more.

Probably better not watch any LS swap videos then.