5.3, versus 6.0, versus 5.7 (1 Viewer)

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workingdog

workingdog

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I have a 66/67 FJ40 with a 60's or early 70' 350 SBC in it and the stock 3 speed behind it.

A while ago, I bought a mid 80's 5.7l (octopus looking intake) with adapter, NV4500 and stock transfer case. I'm now getting ready to actually do something and I wanted to get some input on whether to stick with the 5.7 or move to a mid 2000's 5.3 or 6.0 vortec.

I like the modern vortecs, I have one in my FJ60, the reliability is hard to beat. But I don't know a lot about the mid 80's 5.7 other than I know it was a very popular engine.

This 40 will be the truck my boys learn to drive a stick in and will hopefully supply us years of easy wheeling on fire roads and the occasional real trail.

To answer the questions that will obviously come - I'm ditching the 350 because it was a really crappy installation and because I am tired of wondering if it is going to start on any particular occasion. I am not considering going back to a 2F. It was a great engine in 1965, but in 2013 ...

Thanks in advance for the help.

Peter
 
Is it a TPI? Having driven a 5.7 tpi and a 5.3 vortec I'll be honest the tpi feels more powerful. Don't get me wrong it does not have more power but because it makes its torque a lot lower in the power range and does push over 300lbs of torque it is a great feeling engine.

The tpi is a nice reliable setup that makes great torque and gets pretty good mileage. You defiantly can't go wrong with the vortec but a polished TPI is the single most beautiful looking engine ever produced.

If it was my choice I would run the 5.7 My second choice would be a 6.0. A 6.0 will flat out haul in a 40. A 5.3 is great but in a 40 you might as well go big the mileage will not be much different but the pedal feel is night and day.
 
The mid 80s 5.7 is a 350. It is not hard to make a carburated 350 start well and stay reliable. If you want EFI, any of the first gen throttle body 350 (5.7) setups are very easy to set up. Just did one. John
 
Your octopus intake description leads me to also believe you have a 5.7 TPI engine... nice unit. A buddy and I installed one in Wrangler back in the early/mid 90's. Lot's of fun, great torque, and plenty of hop-ups available if you need more.
 
I tried to find some information on the 5.7 on Wikipedia, but there wasn't much. It is a TPI. So does that engine have a Mass Air, PCM and O2 sensors? What improvements were made when the change to the Vortec line happened?
 
Uhggg, :D it's been almost 20 years.... I can't quite remember.... I think the earlier systems were mass air flow, and the last couple of years of the TPI were map... PCM, yes. They all have O2. I might still have the books we used, but all of the info is likely well established on line.
 
I could find lots and lots of information about the Vortecs, but not any details on the TPI 350's - other than they have a lot of torque - which sounds appropriate for my use.
 
I thought megasquirt was for cars that didn't have ECMs? What advantage would it have over the stock programming.
 
Thanks, that search was productive.

Thy 5.7 TPI engines were released with both MAF and MAP sensors, I'll have to look closely at mine to see what I have.

To answer my own question, MegaSquirt would let you adjust injector flow rate and other fuel injection parameters that would be a lot of work to do using the stock ECM.
 
I've got a tpi 350 in my 40, it's a great engine and has been very reliable for me, but if you have plans for extra h.p. imo you'd be a better off to get a 6.0 right off the bat. The LS is just all the way around a superior engine design
 
I've got a 350 TBI in my fj40 and a lq4 6.0l in my fj75, there both good engines so it probably comes down to what your wanting and what your preference is, my fj40's mostly my offroad truck and personally I prefer running the 350 in it, its got good usable power that works well with the drive train (twin ARBs, 30 spline longfields and H55) and doesn't smash everything to bits, the centreforce clutch copes fine without spinning up or slipping, I think if I had the 6.0l in the fj40 I'd just end up with excess HP resulting in more likelihood of smashing the drive train to bits. My fj75's just a street truck and soft roader now and the 6.0 engines my preference its had a 305 and a couple of 350's in it previously and the 6.0's the best engine I've had in there by far, its running the H55 manual box with an LS1 flywheel and a homemade twinplate clutch (2f pressure plate and 2x 2f clutch plates) with all the auto trans stuff taken out of the stock GM computer, it's made it a really nice road driving truck heaps of power and low down torque, always starts easy and drives smooth I like driving that truck :)
 
The 350 is a good motor and easy to get parts for. The 5.3/6.0 is far superior in just about every way. The problem I'm having is that the 5.3s can be had for damn near the same price as a TPI/TBI any more and they are about easier to find.

I'd like to 5.3l my SWB 45 for on road use and TBI the pig. I would consider speed density TPI. It needs simplicity and ruggedness. It does not need hp. It does not need a MAF that might get wet or dirty. I'd like to be able to see if its getting fuel. If I could get off idle torque I might even consider a 4.3. I don't need 200hp in that truck. It would just break stuff.

Both currently run carbed 350s.
 
check out how cheap 4.8's are going, i see them complete with harness and ecm for 300 around here, and still makes like 275 hp or something like that, but less torque than the 5.3
 
If you have the 5.7 TPI...then go with that. I think the TPI engines only came in teh camaro Go get a manual from Helm that corresponds with the year model engine you have for the respective camaro.

As I recall the tune port only came in the camaro or firebird...late 80's?

If you were to post pictures of the engine its easy to confirm a TPI just based on the intake.

I agree that the new series of SBC are better....but at the time of my swap I had a 5.7 vortec and that's what I used. I really like the output/power of a 6.0 and it seems like a lot of guys like the 5.3 as well Since there are a number of swaps here on the board where they have used the 5.3.

The 6.0 in my pickup runs well and makes plenty of power. IF $$ was no object I would have a 6.0 plus matching 4l85E trans in my LC.
 
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I did the 01 5.3 vortec (LQ9 truck motor) and I LOVE that motor. It gets good mileage (considering 4.88 gears, 37's and aerodynamics of a cinder block), it runs amazing and they are beautifully engineered motors for the mechanic (shade tree or otherwise.)
For me... I didn't need a ton of power. I was after comfortable hwy speeds, reliability, serviceability, parts availability and better fuel economy. All miles beyond the F motor. The 5.3 just seemed the best match for all that was going on the rig and how it was going to be used.
That being said, if you HAVE a motor already. I'd try and make that work. Why spend the extra on different/ similar motor to what you have.
 
1991 - 1992 are speed density (no mass air flow). They make tons of low end torque. They are fun engines. I have one in my 60 :)

Dyno
 
I should have the engine here next week and will post a picture.

Right now, since I already have the 5.7, there's seems little motivation to replace it. The mass air/air pressure sensor is the only thing I'm trying to sort out.

Peter
 
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