4.3 or 5.3

bobdog

4x4 Addict!
Location
Sandy
Originally posted by TigerStripe40
Hmm. That's interesting, because, when I have wheeled with trucks running SBC's they usually have to rev their rpms up to get over stuff I simply idle over. If a SBC had more low end torque, they wouldn't have to rev their motors.

It's true that a SBC CAN produce more torque than an I6, but only in the upper RPM range of their power bands.

I6's have a VERY flat power curve, which means that you get most of your power available at idle. V8's on the other hand have a VERY CURVED power curve (ie Bellcurve). They don't make much power at idle speeds. In fact they make VERY LITTLE, you need to rev them for them to make more power. This is an inherant design in the V configuration of the cylinders. An Inline8 would be a torque MONSTER.



Keep telling yourself that. It sounds just like what I told myself when I ran a I6. The fact is if you look at a dyno graph a mild V8 will probably have higher torque figures at all RPMs. They also are able to idle at a lower RPM and smoother because of the additional two cylinders firing. Of course it is easy to build a V8 that will not idle and that will only make power up in the band but the same thing could be done to a I6. I don't have anything against I6s I thought the Jeep 258 was pretty good ecept for the carb and I don't think you could ever kill the 300ci 6 in my old Ford truck but after having both 6 and 8 cylenders in my Jeep the V8 wins in every catagory off idle, mid range and at high revs.
 

SnwMnkys

Registered User
Location
Orem, Utah
I can start my Chevy 3/4 ton with a stock 350 from a standstill with no gas, just realesing the clutch carefully. I will bet you money, if there was a 4.0 I6 from a Jeep in there it wouldnt be able to, why? Because of the more torque the V8 will put out. Sure the torque curves may be diferent but the V8 will still put out more torque at 1000 rpm then an 4.0 I6 will.
 

grinch

inner city redneck
Location
Salt Lake City
I can start my Chevy 3/4 ton with a stock 350 from a standstill with no gas, just realesing the clutch carefully. I will bet you money, if there was a 4.0 I6 from a Jeep in there it wouldnt be able to, why? Because of the more torque the V8 will put out. Sure the torque curves may be diferent but the V8 will still put out more torque at 1000 rpm then an 4.0 I6 will.

Actually my 4.2 does this no problem also..... Not trying to be devils advocate but it can...... Like I said before they are good engines (that will run poorly forever) there are just better choices out there....
 

SnwMnkys

Registered User
Location
Orem, Utah
Originally posted by TigerStripe40
Start your V8 Without moving, and no gas just by dumping the clutch?? RIGHT...
That's something I would like to see...

Did i say Dumping the clutch? Or carefully releasing the clutch? Learn to read.
 

SnwMnkys

Registered User
Location
Orem, Utah
Originally posted by grinch


Actually my 4.2 does this no problem also..... Not trying to be devils advocate but it can...... Like I said before they are good engines (that will run poorly forever) there are just better choices out there....

If the rig you have that has the 4.2 in weighs the same amount as a 3/4 ton Chevy full size with heavy duty bumpers, a winch, and a full tool box, then ill eat my words.
 

TigerStripe40

Arrogant Bastard
Location
Salt Lake City
Originally posted by SnwMnkys


Did i say Dumping the clutch? Or carefully releasing the clutch? Learn to read.


Actually, the point was that you didn't have any gas. But dumping the clutch, or carefully feathering it doesn' matter. I still want to see you start a 3/4 ton truck, with no gas, that isn't moving, by carefully feathering the clutch, or dumping it, or even using the starter motor.

Or even with gas in it..

Please learn to read your own posts.
 

grinch

inner city redneck
Location
Salt Lake City
Nope the rig i have wieghs close to nothing lol.... its mostly tube... I have removed most of the body.......
Tiger posting reply like that will not make you friends on this bb.... Everyone can have thier own opnion its your right..... You will find that most of the experianced wheelers on this board i.e. those of us who have been wheeling 10+ years will not agree with you on this subject. Alot of us have been down the road on trying to make the straight 6 work.... Most of us have found the cost in getting these engins to preform as well as a 4.3, 350, 5.0 ect is not worth the headach you get from it.... ONE MORE TIME
:rolleyes: :rolleyes: :rolleyes: Straight 6's are not bad engines but this post was about a cheap way to convert a 4 cyl to a better engine.... The tranny used behind the 4 cyl will not bolt up to a straight 6 any easier than a 4.3,350,ect. It is more cost efective to swap one of these engins in that a straight 6... Plus if you ever have rebulit a straight 6 or had it done you know that it costs alot more to do than one of these other engines....
If your gonna bag on somone on reading thier posts then maybe you should read what this post was about...... It wasnt about if he wanted a straight 6 or not.......
 

SnwMnkys

Registered User
Location
Orem, Utah
Originally posted by TigerStripe40



Actually, the point was that you didn't have any gas. But dumping the clutch, or carefully feathering it doesn' matter. I still want to see you start a 3/4 ton truck, with no gas, that isn't moving, by carefully feathering the clutch, or dumping it, or even using the starter motor.

Or even with gas in it..

Please learn to read your own posts.


Oh im sorry i didnt put the word Moving in there, i thought you at least be smart enough to figure it out on your own. Anyone have a server that can store a video file no bigger then 64 megs so i can prove it can be done?
 

tweakeyjeep

Soccer Mom
Location
Sandy
I agree with grinch, i'm not trying to bag on anyone, but my buddy's TJ with the I6 can do the same thing your 3/4 truck can do, but my buddy's TJ is in 2nd gear not 1st. Gearing is an issue as well. I'm not sure how low geared u are, but my buddy is way low geared so he is able to do that. he can almost dump it in 2nd gear, but not quite. :D
 

SnwMnkys

Registered User
Location
Orem, Utah
Your comparing Apples to Oranges. A TJ weighs half the amount my truck does. You put the same I6 in the truck and its not going to happen. I think the Truck has 3.50 gears but im not sure. Its definatley not geared low.
 

tweakeyjeep

Soccer Mom
Location
Sandy
I knew I was comparing apples and oranges :D But I was just trying to open up another reason why that happend, but now that you mention that it is not low geared I retract my previous statement. You've got a good point!
 
man did I start the issue here. Well I still believe that the V configuration provides more torque across the board but not as flat. But come on with gearing ratios and what not just about everyone can idle through stuff. My 2.5L will idle over rocks (Small ones). ALso I just blew the head on my 2.5 so it looks like this project gets a jump start. Still figuring cost for electronics to make the conversion.
 

tweakeyjeep

Soccer Mom
Location
Sandy
Originally posted by JeepTJ38
man did I start the issue here. Well I still believe that the V configuration provides more torque across the board but not as flat. But come on with gearing ratios and what not just about everyone can idle through stuff. My 2.5L will idle over rocks (Small ones). ALso I just blew the head on my 2.5 so it looks like this project gets a jump start. Still figuring cost for electronics to make the conversion.

Sorry to hear about the engine... Keep us updated on what happens.
 

SnwMnkys

Registered User
Location
Orem, Utah
There was a used 2003 GM motor up at NPS today, hell if i know if it ran or not, i couldnt even find the price tag on it. It was a V8 thought, it had those funny looking intake ports that are rounded square at the bottom and a rounded point at the top.
 
Well just for giggles heres what I found.

2002 5.3 vortec plus 4l60e tranny with 6,000 miles for 2225.00 after shipping. I should have it in mid August if it all goes well. Anyone know where to get a D44 or Ford 9 rear for a good price ? I dont think the D35c will last very long.
 

Caleb

Well-Known Member
Location
Riverton
Originally posted by JeepTJ38
Well just for giggles heres what I found.

2002 5.3 vortec plus 4l60e tranny with 6,000 miles for 2225.00 after shipping. I should have it in mid August if it all goes well. Anyone know where to get a D44 or Ford 9 rear for a good price ? I dont think the D35c will last very long.

get a 9" IMO and the are all over at PNP...
 
What sports a 9 rear that is about the same width as a TJ ? Someone said the old style broncos were close. I was going to go with a ford 8.8 but then i was talked out of it becasue of it's C-clip design. to bad cause you can get them for around 400.00
 
Top