Inliners International
Posted By: futten 250 chevy stroker - 10/22/14 08:25 PM
i have been brainstorming maybe harebrained storming but i may be getting my hands ona chevy 250 and i thought hm maybe it will be possible to stroke the thing up in volume sins the 292 crank fits the black and ive found that a ford 302 rod has the right big end specs but is 5.400 lengt and id need a pontiac piston thing is im not real sure if a v8 rod and piston will work on a inline has anyone ever played with 250 chevys?
Posted By: CNC-Dude #5585 Re: 250 chevy stroker - 10/22/14 11:06 PM
The 292 crank in the 250 block is not a very good combo to build. You will be better satisfied with putting the 292 crank in a 292 block and building it that way.
Posted By: futten Re: 250 chevy stroker - 10/23/14 01:24 AM
finding a 292 in norway is like finding a needle in a barnfull of haystacks and theres about a 100 barns and one needle
Posted By: CNC-Dude #5585 Re: 250 chevy stroker - 10/23/14 02:55 AM
I would just build a 250 then. Also, the combo of parts you are considering make a much worse combination because the rods are way too short. Even with using the 250 rods in the traditional 292 stoker, they are even too short also, and they are longer than the Ford rods you are considering. Also, the 302 Ford rods are much too narrow as well, and you couldn't even use them.
Posted By: futten Re: 250 chevy stroker - 10/23/14 03:31 AM
damn!
Posted By: futten Re: 250 chevy stroker - 10/23/14 03:45 AM
i found if i can use a 5.7" rod ment for the 250 i can use a ls1 piston with a 1.34" compression height what are your thoughts there??
Posted By: 70Nova Re: 250 chevy stroker - 10/23/14 09:50 AM
What is your intended use for the engine? Low rpm cruiser/tractor or a screaming race engine? Look at rod ratios: you need a LONG rod with the long stroke, or piston speeds will get too high. It would run ok at low rpms, theoretically, but could not survive higher rpms. With the long stroke, and long rods, you would need extremely short pistons. Not sure that combo exists, you may run out of cylinder height no matter what.

http://victorylibrary.com/mopar/rod-tech-c.htm
Posted By: strokersix Re: 250 chevy stroker - 10/23/14 12:12 PM
I've done it with 4 inch 383 small chevy pistons and stock 5.7 250 rods. Needs a LOT of counterweight cut to clear wrist pins but it works. I don't recommend 4 inch bore either...

Better is 6.0 aftermarket rods and custom pistons. My current engine is 4.062 stroke, 6.0 Crower rods, and custom JE pistons .060 over. Runs good. Not cheap.
Posted By: futten Re: 250 chevy stroker - 10/23/14 12:43 PM
well it would be a hopped up street engine not a real high rpm screamer i wouldent go over 4" bore i think the engine is bored 30 over but it would be fun to end u with a 300 cid six banger with some good power ina 250 package kinda like a 10 pounds of shit i a 5 pound bag kinda thing to haul som v8 guys ass and when the wants to see the engine all he sees is a littl
e ol 250
Posted By: CNC-Dude #5585 Re: 250 chevy stroker - 10/23/14 02:24 PM
Any type of build like this has pros and cons, you will just have to see for yourself if its worth that, versus finding a 292 block to build it from. Most people in Norway probably couldn't tell the difference between a 250 and a 292 by looking at them anyway if they are that scarce over there.
Posted By: Chevelle292Wagon Re: 250 chevy stroker - 10/23/14 03:26 PM
Originally Posted By: CNC-Dude #5585
Most people in Norway probably couldn't tell the difference between a 250 and a 292 by looking at them anyway if they are that scarce over there.


Ha! Most folks in this country can't tell either : )

I wonder though if a 250 with a turbo from a Saab or Volvo might be more cost effective? (seeing how Sweden is right next door to Norway)
I'm assuming/hoping there is a suitable Turbo that he can use.
Posted By: 70Nova Re: 250 chevy stroker - 10/23/14 04:36 PM
a used stock turbo from a saab or Volvo would be a bit small, 2.0 - 2.2 dispacement engines and low boost kicking in early in the native application.... it would spool up quick with a 292 smile
Probably makes boost at idle, LOL

But yea, turbo could be the most cost effective choice and make decent power with a near stock 250. Turbos help make torque and power at low/normal rpm range, so the engine would not need to rev any higher than stock.

Posted By: panic Re: 250 chevy stroker - 10/23/14 05:27 PM
The 292 crankpin is 2.100" (same as 1968-* SBC), the Ford is larger at 2.123".
The mean piston speed in f/m is entirely controlled by the stroke length: stroke × RPM ÷ 6. Piston acceleration varies slightly with the rod ratio.
Based on the 250 deck height of 9.15" and the 292's 4.12" stroke, a 5.40" rod makes the piston CD about 1.69" - which is fine for the piston but makes for a very bad rod ratio (1.31:1), and a high rod thrust angle: 22.4°.
Even with the V8 5.7" rod, the angle is 21.2°, very bad.
A 6" rod is better at 20.1°, but the piston is way too short at 1.09".

Best advice: just get a 292 motor.
Fast & cheap 250: Eaton M90 from eBay for $300.
Posted By: futten Re: 250 chevy stroker - 10/23/14 11:04 PM
what about my re "design of 5.7 rod and ls1 piston with a 1.34" compression height??
Posted By: panic Re: 250 chevy stroker - 10/24/14 01:20 AM
Even with the V8 5.7" rod, the angle is 21.2°, very bad.
Posted By: futten Re: 250 chevy stroker - 10/24/14 02:50 AM
danger of rod smackin the bottom of the bore?
Posted By: strokersix Re: 250 chevy stroker - 10/24/14 10:18 AM
Don't forget how much crank counterweight you will have to trim to clear the wrist pin at BDC. I turned my crank weights round as far as I could, then "pendulum" cut them some more to clear 5.7 rods. And mine is destroked to 4.062 as well. I used this same crank for three builds. First two builds were 5.7 250 rods and 383 small chevy pistons at 4 inch bore. Last and current build is 6 inch rods and custom pistons, same crank. I've run all three hard street duty for fun. Not racing.

6 inch rods means you won't have to trim as much in addition to improved geometry as pointed out above.
Posted By: futten Re: 250 chevy stroker - 10/24/14 10:55 AM
so it can be done but not an ideal setup geometry wize
Posted By: CNC-Dude #5585 Re: 250 chevy stroker - 10/24/14 02:08 PM
Well, the 6" rod does improve the geometry a little bit, but the main point is that it costs a lot of money in both parts and labor to put a 292 crank into a 250 block, and probably makes it considerably more expensive than just using a 292 block to begin with. It would still be cheaper to ship a block from the US and build a 292 that way than to build one as a "stroker" using a 250 block. You need to start pricing machine work over there and see what it is going to cost to cut the counterweights down to clear the pistons and re-balance it afterward, along with the pistons and rods for the swap.

Its going to be cheaper to build a turbo 250. You can get many properly sized turbos off of eBay very reasonable, and you don't need any custom parts internally to do it.
Posted By: futten Re: 250 chevy stroker - 10/24/14 03:46 PM
i can do some machine work myself and sins the crank and rod journals are the same size then no line bore needed
Posted By: CNC-Dude #5585 Re: 250 chevy stroker - 10/24/14 04:47 PM
Let us know how it works out for you.
Posted By: strokersix Re: 250 chevy stroker - 10/24/14 04:49 PM
Reason I did it was to look like a stock 250 externally. That's the only justification that makes any sense.

In terms of cost and durability I would choose a 292 block.
Posted By: Twisted6 Re: 250 chevy stroker - 10/24/14 07:41 PM
Originally Posted By: CNC-Dude #5585
Well, the 6" rod does improve the geometry a little bit, but the main point is that it costs a lot of money in both parts and labor to put a 292 crank into a 250 block, and probably makes it considerably more expensive than just using a 292 block to begin with. It would still be cheaper to ship a block from the US and build a 292 that way than to build one as a "stroker" using a 250 block. You need to start pricing machine work over there and see what it is going to cost to cut the counterweights down to clear the pistons and re-balance it afterward, along with the pistons and rods for the swap.

Its going to be cheaper to build a turbo 250. You can get many properly sized turbos off of eBay very reasonable, and you don't need any custom parts internally to do it.


Tom Langdon Used to sell a kit for around 1000. But I don't know if he still does or not.
Posted By: CNC-Dude #5585 Re: 250 chevy stroker - 10/25/14 12:05 AM
That wasn't a bad price for someone wanting to be a little "stealthy".
Posted By: efi-diy Re: 250 chevy stroker - 10/25/14 10:16 PM
For the cost of the parts - why not get a vortec 4200 out of a Saab 9-7? The 2008 engines were 291 HP STOCK. Build a header and do some exhaust port work and you will have a 325HP engine.

Or add a turbo and get 400+ HP easy...
Posted By: futten Re: 250 chevy stroker - 10/25/14 11:46 PM
saabs have chevy inliners??? ive worked on some saabs in my day and never seen this
Originally Posted By: efi-diy
For the cost of the parts - why not get a vortec 4200 out of a Saab 9-7? The 2008 engines were 291 HP STOCK. Build a header and do some exhaust port work and you will have a 325HP engine.

Or add a turbo and get 400+ HP easy...


Still have not seen an invoice of what your build cost.
Always suggesting a 4200, which is fine, but not seeing what your build costs? What are you hiding, asked you before what your build cost w/no response.

It's not cheap

MBHD
Posted By: THE FRENCHTOWN FLYER Re: 250 chevy stroker - 10/26/14 01:44 PM
Originally Posted By: efi-diy
For the cost of the parts - why not get a vortec 4200 out of a Saab 9-7? The 2008 engines were 291 HP STOCK. Build a header and do some exhaust port work and you will have a 325HP engine.

Or add a turbo and get 400+ HP easy...


Why are many rodders still building Flathead Ford V8s at twice the cost of a SBC with half the potential HP output? I guess some (many) folks like traditional engines. Otherwise Inliners International would have little reason to exist. You could just hook up with one of many modern techno geek websites that deal with modern tuner car engines.
Originally Posted By: efi-diy
For the cost of the parts - why not get a vortec 4200 out of a Saab 9-7? The 2008 engines were 291 HP STOCK. Build a header and do some exhaust port work and you will have a 325HP engine.

Or add a turbo and get 400+ HP easy...


A break down of parts would be a good start. cool

Forged pistons, cyl sleeves + cost to install sleeves. eek

Two piece billet turbo exhaust manifold. eek

Port & polish + larger valve installs on 24 valve cyl head. eek

Custom camshafts. eek

Trans adaptor as to run a TH400 4l80E , etc.

I know there is more to it than what I mentioned.

A ball park price on these items would be good.


MBHD
Posted By: efi-diy Re: 250 chevy stroker - 10/26/14 09:25 PM
Originally Posted By: THE FRENCHTOWN FLYER
SNIP
Why are many rodders still building Flathead Ford V8s at twice the cost of a SBC with half the potential HP output? I guess some (many) folks like traditional engines. Otherwise Inliners International would have little reason to exist. You could just hook up with one of many modern techno geek websites that deal with modern tuner car engines.


Except the 4200 is not a tuner car engine now is it - it came in a GM truck.

The original stock engine turbo build cost:

$1000 for the engine
$800 for the turbo
$200 for the MS2 kit.
$750 for the turbo manifold.

Mind you this was in 2007/8 so things have changed - the cost of the engines have dropped. I could have gotten a good used turbo but didn't.

Quite a few people are now using the stock exhaust manifold and a U up pipe to mount the turbo on and have good results.

For a budget build this should be doable for ~$2000 with a used engine/turbo.

Go look at what others are doing - vortec4200.com

Originally Posted By: efi-diy
Originally Posted By: THE FRENCHTOWN FLYER
SNIP
Why are many rodders still building Flathead Ford V8s at twice the cost of a SBC with half the potential HP output? I guess some (many) folks like traditional engines. Otherwise Inliners International would have little reason to exist. You could just hook up with one of many modern techno geek websites that deal with modern tuner car engines.


Except the 4200 is not a tuner car engine now is it - it came in a GM truck.

The original stock engine turbo build cost:

$1000 for the engine
$800 for the turbo
$200 for the MS2 kit.
$750 for the turbo manifold.

Mind you this was in 2007/8 so things have changed - the cost of the engines have dropped. I could have gotten a good used turbo but didn't.

Quite a few people are now using the stock exhaust manifold and a U up pipe to mount the turbo on and have good results.

For a budget build this should be doable for ~$2000 with a used engine/turbo.

Go look at what others are doing - vortec4200.com



Thanks for some info, not all though. frown

Just trying to help you out on selling the 4200 over here on this forum.
Since you continually suggest for guys to stop wasting there money on the 194-292's & to install a 4200 for cheaper for more power.

A good break down on what parts to get & parts needed to build one of these would serve your cause better I would think.

A master list of parts & cost would be great for you to post here instead of just saying the same thing over & over & over again, with nothing to back up your plan of installing a 4200.

J.M.O.

MBHD
Posted By: intergrated j 78 Re: 250 chevy stroker - 10/26/14 10:34 PM
I have owned and currently have a 4200. IMHO great swap material. But like The Frenchtown Flyer says some people like me would just rather have the older
engines at twice the cost and half the power. After all a stock smooth running 4200 would be well over 300 HP with just a decent exhaust system. Much harder to get that kind of power out of a naturally aspirated 235 or 250. A 292 would still be far off without mods. I will probably swap one in something someday but for now I will stick with the older engines. Jay 6155
Posted By: 70Nova Re: 250 chevy stroker - 10/26/14 10:55 PM
I don't think many of us are here to find the "easy way" smile
Certainly not gonna find the cheapest way. That would be a $500 junkyard 350 V8, running in a weekend and making more power and torque than our sixes. But I'm not interested in easy or cheap. Not when it's about engines anyway. wink
Posted By: futten Re: 250 chevy stroker - 10/27/14 04:56 AM
whats fun with quick and easy? i like learning and finding out stuff and building a sleeper engine showing up with a box of tricks and everyone thinks you have a lame little 250 not knowing whats hiding inside
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