SBC vs 2F

[Off Duty]

Cool, though, I think the FJ by itself limits how far you can push it. Don't expect sharp turning, don't expect to drag race between lights, or go vertical (though that sure as hell can be fun).

So it truly is to try and get everything out of the FJ. Thank you for supporting this thread.

...Buy a Porsche...a Corvette, and a motorcycle. Problem solved.

this thread is all over the place...

...Ain't that a fact!
It bounces from one "problem/solution" to another.
We've gone from what do you think of the SBC v. the 2f, to the Mercedes Benz engine, to f**king autocrossing and street racing
Is there really a point to the thread, or is this controlled by a bot?

IF... a 2 f is properly cared for it will outlast any small block 3 to 1. Yes... the small block has more Horsepower.. the 2 f has more torque. the 2 f runs cooler, and CAN be built to have nearly the same horsepower as a mild small block. I like both, and the only reason my 40 has a small block, is because it was cheaper than building a nice 2 f.

I'd have to disagree with your assessment of the 2f outlasting the SBC. If both are equally maintained, I doubt seriously the 2f will outlast the SBC without more extensive maintenance at some point.
The newer LS engines when properly maintained, are good for a couple hundred thousand easily. Refresh, and start all over. Rebuild/refresh costs? About the same, maybe slightly less for the SBC.

IIRC, they both make good torque, just at different RPM ranges. The SBC is designed to rev higher. I had an L98 in an 87 corvette. They didn't call it a "Tourqe monster" for nothing

Two things I'd like to see when building the 2f to match a "mild" SBC.
1) the longevity after the build.
2) the cost sheet.

Drop that same money in a SBC, and there's no comparison on either. As you said, it's cheaper to build the SBC

 

[Mace]

Historically 350's were a 100K engine. The newer ones have changed that considerably. During the time the 2F's were being built, the Chevy power plants did not last as long with similar upkeep.

 

['74 UA FJ]

this thread is all over the place... IF... a 2 f is properly cared for it will outlast any small block 3 to 1. Yes... the small block has more Horsepower.. the 2 f has more torque. the 2 f runs cooler, and CAN be built to have nearly the same horsepower as a mild small block. I like both, and the only reason my 40 has a small block, is because it was cheaper than building a nice 2 f.

A 2F doesn't approach the amount of torque that most stock 350s deliver.
2F: 210ft-lbs @ 1800
350: ~300 ft-lbs @ 2300

Now people like to say "But a 2F makes more torque way down low in rpms." Take that 350 that makes 300 at 2300 and look at 1800rpm on the dyno chart and you'll see that it makes more than 210.

Historically 350's were a 100K engine. The newer ones have changed that considerably. During the time the 2F's were being built, the Chevy power plants did not last as long with similar upkeep.

I have no date to back this up other than observation of driving tons of 70s and 80s chevy pickups, but I'd be surprised if the average lifespan of a 350 built in the 70s was less than 150,000 miles.

 

[jmdaniel]

I have no date to back this up other than observation of driving tons of 70s and 80s chevy pickups, but I'd be surprised if the average lifespan of a 350 built in the 70s was less than 150,000 miles.

I agree. Born and raised in the upper Midwest, my experience was that the cars would rust out before the motors were done.

 

[Mace]

I agree. Born and raised in the upper Midwest, my experience was that the cars would rust out before the motors were done.

Which happened in about a year and a half

 

[Off Duty]

I don't know. All I know is I've had a bunch of small block chevy's from the time I started driving until now, and all of them have gone well in excess of 100k.
I was crappy with the upkeep and beat them like a red headed step child!

 

[Enigma]

The only thing I ever broke on my SBC 350 fj40 was the transfer case, a couple of times
When I first got it, the 350 was already in it, along with a M22 4 speed, AA adaptor to 3 speed tcase and stock 4.11 axles on 31" tires.
Being the young fool I was then, constantly drag racing it, burning rubber, and always trying (and succeeding) to get that tire chirp through all 4 gear changes.
This resulted in a the aluminum housing of the transfer case to literally tear in half, and then drag it behind me by the brake cable as I coasted to a stop.
If I had known about the "Tcase saver", this probably would have been avoided, perhaps breaking drive shafts inside.
Long story short, drive like an idiot you brake stuff.
Since then, the tranny has been replaced with a SM465, and age/wisdom (along with a slow shifting truck tranny) and no more broken parts.
The 2f is a great engine, but a SBC is just wayyyy more fun.

 

[bikersmurf]

At idle, my 1.5F would keep chugging along without spinning the wheels if I needed to give it a little throttle. I'd recomend keeping your 2F for as long as it runs, and replacing it with annother 2F if it were to die.

That said, my 1.5F died, and I don't regret replacing it with a stockish 350. I've added a Quadrajet, an RV cam, and dual exhaust... But other than that, it is as it drove onto the showroom floor. New it was a 250 hp 350, now I'd estimate more like 300 hp. It chugs along at idle very nicely... But if you give it a little gas, the tires will easily slip. On the highway it has all the power you'll ever need. It will also run all day long at 3000 rpm without complaining.

Costs... My F and 2F were going to cost $3000 + for a basic rebuild... For that I can get two crate 350s or one very nicely rebuilt 350 with higher end components... Not just a basic rebuild.

Don't get me wrong, I loved my 1.5F... But they're not cheaper in the long run.

 

[Brian in Oregon]

His engine builder sucks..

Exactly my point, might have only seen V8s if the F engine had to be rebuilt often.

And I run with people who have V8s, one having a stock V8, and yes, it works well, has grunt, but we had to stop for him to refuel rather a lot, and he brought a whole car of parts in it.

Which brings in that other point! "Anything man made will break at some point, no matter what you do."

You're guessing.

The issue is he and his son were trying to drive the Toyota six at interstate speeds like it was a V8, at high sustained RPMs, and the motor is not designed for that. This is where a V8 is more suitable.

 

[Brian in Oregon]

A 2F doesn't approach the amount of torque that most stock 350s deliver.
2F: 210ft-lbs @ 1800
350: ~300 ft-lbs @ 2300

Now people like to say "But a 2F makes more torque way down low in rpms." Take that 350 that makes 300 at 2300 and look at 1800rpm on the dyno chart and you'll see that it makes more than 210.

I have no date to back this up other than observation of driving tons of 70s and 80s chevy pickups, but I'd be surprised if the average lifespan of a 350 built in the 70s was less than 150,000 miles.

Well, you have to take that with a grain of salt. While on paper that is true, it may or may not apply to an individual application. Case in point...

When I first bought my FJ40, with a 350 (and Toyota 4-speed) it had no low end torque and often required a healthy blip of the throttle to keep from stalling when pulling out.

Once it was rolling, it ran like a striped ass ape. Made lots of power. But the gas mileage was still as sucky as the I6.

The problem was the carb.

The PO had a Holley 650 Truck Avenger installed, and while this is a good performance carb, it has almost no low end response while the throttle blades transcend past the off idle slots. No amount of tweaking to the accelerator pump could compensate. The problem was so severe that you could not even make a second gear start.

I installed a QuadraJet. This was a tradeoff. I lost the mid and especially top end power, though to be sure the power it did make was still in excess of the I6. But the low end power was now nearly as good as the I6. First gear starts are very easy without the need to mash the go pedal. In fact, I can do THIRD gear starts on level ground, and second gear starts on mild hills. It almost lugs as good as a six.

The rest of the engine is bone stock except for the small tube block hugger headers and the overly large dual plane intake. When the headers go out they will be replaced with rams horns. At some point I'd like to install an aluminum small runner dual plane intake. The cam is stock, not even an RV.

I think it is fair to say my setup is a mild V8 swap, not a hot rod. And that was the main point I was making in my earlier lengthy reply. There are two kinds of V8 swaps. Stock and hot rod. One does not require much in the way of upgrading the drivetrain, though a case saver is always a good idea. The other may well need beefed up components.

 

[Elbert]

A 5.7 engine swap is a great solution.....how you want to control fuel flow is another consideration (fuel injection vs. carb). SBC 5.7 is very dependable....plus I can buy most any part in "anywhere USA"...

SBC are not prone to repair issues and the newer fuel injection versions last a long time... Plus mine cranks with one twist of the key (no matter how hot or cold).

A SBC of any flavor is a proven solution and very dependable once you work through the swap issues.

If you care a whole lot about MPG then I think you might as well turn in your cruiser keys to start with...

Personally I think my swap to a V-8 and Yota 5 speed have made the truck more fun to drive....and yes I've had some gremilins with the marks setup and fuel injection but I would do it all over again. My 5.7 vortec is stock except for different exhaust manifolds, removal of some emissions crap, and custom PCM programming (engine internals are stock)....no leaks and makes good power.

Nothing unique about swapping over to a 40...that I know off...if carbed I think I would run a q-jet, if not then I would go fuel injection (GM flavor).

 

[bikersmurf]

The biggest factor to consider with a converted 40 is how well the conversion was done. Far too many V8 conversions have been done after the 2 4 was finished. A "Molsen" degree dosen't make for careful engineering.

I've seen some nice ones here on mud... But most I've seen in person are total hack jobs that shouldn't be on the road.

The biggest benefit to a stock Fj40 is the careful engineering that went into it. Far too many 40s suffer from what POs and current owners have done to them to improve them.

 

[Brian in Oregon]

My 350 is a cold blooded bastard. Must be fully warmed up in any time other than summer.

The previous owner had an issue with the Marks of Australia conversion kit, but that was because they did not follow the instructions when it came to the type of clutch to install. Once the right clutch was used, no more problems.

I sure wish I had a five speed in mine. It really needs an overdrive gear.

Yeah, mileage is sucky. That tends to limit extended range trips. I calculated the fuel expense difference to drive the FJ40 to Yellowstone vs the wife's RAV4, and it was about $350. The FJ40 would be more fun with the roof off, though. But there aren't many places there that a RAV4 can't go. But for hunting trips here, yeah, the RAV4 would be scrap metal, while the FJ40 shines. The RAV4 ain't gunna be fording irrigation canals or flooded areas either, while it's routine for the FJ40. Some of the roads are "paved" with sharp three inch rocks, no gravel. The FJ40 can take tires with heavy enough lugs and plies for that. The street tires on the RAV4 would be busted quickly.

The FJ40 is a tool, and like all tools, it's better suited to some jobs, but not for others.

 

[Mace]

You're guessing.

The issue is he and his son were trying to drive the Toyota six at interstate speeds like it was a V8, at high sustained RPMs, and the motor is not designed for that. This is where a V8 is more suitable.

No I'm not. What do you consider freeway high rpm's?

 

[Brian in Oregon]

Around 4000 rpms sustained.

 

[psreno]

4000? Really?

I don't think I go past 3500, ever. Just no need, and that's with a 4 speed and 31's. I think I'm cruising at 70 around 3200. Ya got like 3.11's in the rear?

 

[toyotalandfj40]

Due to having a ECU with the 2F, I can get 6000 (don't do that for too long), but I can run about 80 at only 3500 (that's my read out when I plug in my laptop).

 

[Bret]

FWIW (which ain't crap) when I first got my 40 it had a GM 250 straight six in it, it had enough power to move around but not enough with 35's and lockers. Once you got it bogged down a little the clutch would get a workout or smokeout. It started to lose oil pressure and I thought I would wait until it died to swap it out. After over a year I swapped it anyways for a mid 70's bone stock 350. Ran and never falted. Had a lot more oomph than the 69 250 that was removed. 2 years later I wanted to renew the entire drivetrain and went H55 with a HT383, small Dart heads and fuel injection. The motor pushes over 400 ftlbs above 2K and can easily turn the tires from 400 rpm up. If I was looking at bulding a SBC I would do a low compresion stroker with small intake runnes etc. for all bottom end grunt. Easier on parts and still enough HP on the top end to scare the crap out of you on the highway. A SBC and H55 is a very good fit and if it lacks anything it is very low gears.

 

[Brian in Oregon]

4000? Really?

I don't think I go past 3500, ever. Just no need, and that's with a 4 speed and 31's. I think I'm cruising at 70 around 3200. Ya got like 3.11's in the rear?

3.11's?

 

[Pighead]

[QUOTE='74 UA FJ;7274902 look at 1800rpm on the dyno chart and you'll see that it makes more than 210.



[/QUOTE]



Still too fast. The beauty of the F series is that they'll pull you up a rocky hill at 400 RPM...