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Opinions Wanted: Stroked 258 I6 vs. 283

6K views 34 replies 16 participants last post by  kufd 
#1 ·
Ok, my current 83 has an Iron Duke mated to a (GM bolt pattern) T176/Dana 300 combo. My 80 (getting torn down for rebuild) has a 258 mated to the same (AMC bolt pattern) T176/Dana 300 combo. The Iron Duke just isn't going to cut it for my needs (I-75 driving 70/80 MPH) and some mild to medium trails. I looking for opinions from you guys who have a stroked 258 or a 283. I'm interested in the power, MPG, torque, etc! Which would you guys reccommend?

Thanks for your opinions :cheers2:
Rick
 
#5 ·
I'd go for the SBC. V-8 is going to beat that one, probably in both power and cost.
Plus, once it's in, you're set up to drop a bigger SBC in whenever the mood (or money) allows.

Look at the TRUE cost of making any power with a stroked 258. Those "crate" stroker 4.6's claim 260hp.

A 283 stock is already going to likely have that much, and even more if it's even mildly modified. It's going to bolt right up to your bell housing, too.

I'm just not a big fan of the stroked 258's.....to me, it's a lot of money for how much power you ultimately make. Even if you miraculously managed to have one make 300hp, (unlikely) you could kill that figure for less money with a small block.

Now, if you lived somewhere that it was illegal to swap in an SBC, I might change my tune, but otherwise, go for the V-8.
 
#6 ·
I'd go for the SBC. V-8 is going to beat that one, probably in both power and cost.
Plus, once it's in, you're set up to drop a bigger SBC in whenever the mood (or money) allows.

Look at the TRUE cost of making any power with a stroked 258. Those "crate" stroker 4.6's claim 260hp.

A 283 stock is already going to likely have that much, and even more if it's even mildly modified. It's going to bolt right up to your bell housing, too.

I'm just not a big fan of the stroked 258's.....to me, it's a lot of money for how much power you ultimately make. Even if you miraculously managed to have one make 300hp, (unlikely) you could kill that figure for less money with a small block.

Now, if you lived somewhere that it was illegal to swap in an SBC, I might change my tune, but otherwise, go for the V-8.
Even though you are a Pac fan, thank for your input.
HEELS RULE :2thumbsup:
 
#8 ·
I would go with the a bigger motor, Imo, the 283 is a good motor, but it's not a low down torque motor, it's small so it has to rev up to make much. IIrc, they are from the 50's/60's, so any that you find will not have valves and valve seats that will live long with modern unleaded.

I would look for a 350 or other larger SBC motor, unless you have or can get the 283 in good shape cheap.
 
#9 ·
How do you stroke a 258? Or are you talking about a 4.0L-based stroker? I have a 4.6L stroker in my Scrambler and love it. The 283 Chevy is as good as any other SBC (why not a 350? the block is the same size, if you're going to swap why not go with bigger displacement??), but is a whole different animal than an inline 6. Not a torque motor at all. High reving little screamer than makes HP at high rpm. Not a good Jeep engine. And to whoever said above that a 283 makes 260hp stock, I laugh. Stock ratings were in the 160hp-185hp range.
 
#18 ·
And to whoever said above that a 283 makes 260hp stock, I laugh. Stock ratings were in the 160hp-185hp range.
You are wrong. The Chevy 283 was the first factory V8 to claim 1hp per cubic inch, in the 60's you could order a 283 with 283hp. Stock ratings were in the 160hp-283hp range.
 
#10 ·
Here are my thoughts on this the small block is a good little engine on the other hand its a higher reving engine here are the specs for the 283.

Model Designation: 150, 210 & Bel Air (all engines available) Wheel base: 117-1/2 Valve Location: In head Bore and Stroke: 3.875 x 3.000 Piston displacement, Cubic Inches: 283 Compression ratio: 8.50 Maximum Brake Horsepower: w/2-barrel carb: 185 @ 4600 RPM; w/4-barrel carb: 230 @ 4800 RPM Maximum Torque Lbs.Ft. @ RPM: w/2-barrel carb: 275 @ 2400 RPM; w/4-barrel carb: 300 @ 3000 RPM Normal Oil Pressure Pounds: 35
Now have a 4.7 stroker in my 85 Jeep and for the most part I really like it. The only area that has given me any headaches are the fuel delivery I tried the Howell TBI setup and it just did not work well. The Howell TBI is somewhat programmable but it really is very limited. The major problem is the very unequal length of the intake runners, which cause's more fuel to be delivered to the shorter runners and less to the longer runners.

I over came this with a Weber Redline TBI system which works very well. But I think I will go to a Weber Redline MPI setup.

Horse power numbers are are over rated its torque that moves you down the road. And a stroker has a lot of torque. Here is a picture of my 4.7 with the Howell adapter.

And here is a friends 4.9 stroker that he built for Bonneville for his World Fastest Jeep Comanche it puts out over 400 HP and over 400 Ft Lbs of Torque it was tested at the Hesco Dyno so its not a theoretical build.

Now you can go either way and both have their advantages and disadvantages. Building a Stroker has a very " HIGH GEE WHIZ FACTOR" and you can go from mild to wild but its more of a old school hot rodder thing where you have to experiment to get that right combination to make it work. A SBC has all kinds of stuff off the shelf so it more an assembly type build.

And what ever you do dont buy a pre manufactured stroker every one of them is garbage. Mine started out as a Golen and lasted less than 5000 miles (poor assembly) My current version is 10,000 and still going strong and it will last a really long time.
 

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#11 ·
Everyone quoting HP numbers on 283s needs to take a lesson on the difference between gross and net HP ratings. After 1971 all HP numbers are net ratings, which are 25-30% lower than gross ratings. So take your 185hp (gross) 283 and subtract 25% and it puts out a whopping 139hp (net). Even a stock 4.0L was 180hp (net). No comparison. Sure, the fuel injected high-zoot version of the 283 put out 283 hp (gross, only 212 net), but try finding one of those nowadays. Even a modestly built 4.XL stroker will put out 240hp (net) with ease, and up close to 300 lb/ft of torque. A stock 2bbl 283 only put out 275 lb/ft at 2,400rpm.

Here's a good discussion on the comparison between a 4.XL stroker and any small block V8. Jeep Strokers • Stroker Horsepower & Torque Numbers VS. Small Block V8's
 
#19 ·
Problem with that link is, they are comparing flywheel HP/Torque figures from strokers with RWHP figures for Small Blocks. They claimed their figures were all from the flywheel, but that is false. I know some of those engines they are talking about, and they are wheel HP, not flywheel.

Look at the RWHP dyno sheet for a stroker 4.6 a few posts down on that link:
258 Torque
201 HP...and it doesn't get there until the engine's almost wound out.

Less power than one of the stock 305's listed in the thread.

And from the link:

Note: There's no doubt nor argument here that SB Ford and Chevy V8's have huge aftermarket support and will be both cheaper and easier to get higher power from. 275-300hp is a few bolt ons away for most any small block V8. This thread is intended to show the value of a Stroker build versus swapping in a stock small block. It is not an argument over which has the most potential for high end power! The stroker gets very expensive very quickly.
I rest my case.
Do the math. If you do one of these strokers RIGHT, you will have over 3k in it, no if's and's or buts. And what will you have for 3k? 300 ft/lbs of torque, give or take.
A stock 96-2000 Chevy Truck/SUV Vortec 350 has 255hp/330 ft/lbs torque. And that's at the wheels.
How many of those does everyone think are out there in salvage yards? Get one with the fuel system and computer, cheap. Does anyone seriously think it would take over 3k to have one of these running in a CJ?
Slap it in, spank anyone's stroker.

I don't mean to seem like I'm raining on anyone's stroker parade....if you're in love with the 6 cylinder, then by all means build one. But just don't try to sell me on it with the "less money" angle....it just ain't so. It's a lot of money to basically get almost even with a 70's smog motor small block, and still won't be even with even a 302 Mustang engine of the late 80's or 90's.
 
#17 ·
Why would he want a downgrade? :laugh:

For the cost of the stroker and all it'll take to get it "right", he could rebuild the 283 if he's dead-set on that motor, and still come out ahead on the HP.

There's just no comparison....you have to work hard to get HP out of that 6 cylinder.....but take that V-8, slap some good heads on it, a mild cam and an intake, and you're rolling.

And even if you get 275hp out of the 6......he's obviously after more power. Most folks won't be satisfied with 275hp for long.....they will be at first, because it's better than stock....until their buddy with a stock 350 spanks their butt from a stop light, and he has less money in his entire conversion than you do in just your motor.
 
#23 ·
That's what I'm talking about....in this case, he doesn't even need a bell housing adapter....he'd actually have to get another bell housing to put the 6 in there, unless his has two bolt patterns on it.

The SBC will bolt right up, just need engine mounts.....and he's going to need those for either engine he chooses.
 
#26 ·
Which ever swap you do.
Don't forget the cost of a few other things, radiator, motor mounts, exhaust, etc.
Do your homework. So you have the total cost of the project before starting.
Have some extra cash in the bank for stuff you did not plan for.
It is always better to have something that moves and still runs than a 1/2 finished project that needs funds.
 
#27 ·
Well to clarify the stoker was built by the kid who is selling it, his Dad did all the machine work. He say he has around $800 in it but will sell it for $400 firm. My only problem is, it was never put in the CJ, he ran out of money and sold the Jeep, now he is trying to recover some of the money. He has no way of firing it up, so I really have no way of what I'm getting in the engine. My thinking is going with the 283 but I'm sure the stroker will get better mileage but not sure if the offset in gas saved is worth it?
 
#28 ·
I see no reason the stroker will get better mileage, unless it's because it's a less powerful engine.

Neither is a paragon of fuel efficiency, but I don't think there'll be that much difference.
 
#33 ·
Well, I talked to the guy a week ago and he said he would be pulling it this weekend and I could come pick it up. I told him I would come over and help him pull it, he's said that's cool, see ya Saturday. So last night I pulled the $200 out of the ATM and called him at 9 am to verify today was the day. His reply was, him and his buddy pulled it on Wednesday and he sold it to his buddy for $150 All I have to say is :ranton::rantscream:That sorry @$$ MFSOB better never need my help again with his computers, Yea I'll gladly fix them at $100/hour:rantoff:
 
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