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740 NA: Clean Slate for Something More?

@Vincent Gagnon:
Thanks for the tip. Would like to know more of what you're thinking here ;-)

@Jack:
Location is not an issue for this. All kosher --

@everybody else:
Thanks for the ongoing comments...
 
Jack said:
been wrong on more than one occasion but its not just the rods that make it stout
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You?re right. There was a difference in material used in the block casting and they wear extremely well in comparison to the b230 engines (which also wear pretty well).

But mainly it?s the rods that make the bottom end so stout.
 
PromiseRing said:
You’re right. There was a difference in material used in the block casting and they wear extremely well in comparison to the b230 engines (which also wear pretty well).

But mainly it’s the rods that make the bottom end so stout and heavy and slow to rev compared with any design after 1969
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Very interesting...now you know about cast iron?

Where'd you learn that? Link!

It couldn't possibly be a combination of a better wrist pin locations and longer rods and the resultant reduced tendency for side-thrust from less rod angulation, and pistons wanting to tip?

Why do you suppose everybody else in the world had gone away from pistons with compression heights in the 45-46mm range--except conservative old German Opel by the late 60s? And everything from Japan to USA to Germany and Sweden had gone to pistons with compression heights around 39,5* to 41,5mm...And by the early 80s around 35mm?
And by the 1990 around 30-32mm? Everybody..from Japan to Germany and America.

Do tell.
You have an opinion on everything, that's fine..But tell us some facts..

And you seem certain that the forged steel crankshaft that is bigger in every dimension that a Small Block Chevy crank contributed nothing, it was the rods that made the B21/b23 stout..Hmmmm Live and learn..



*Even Volvo themselves with the introduction 15 years after everybody else of the B200/B230 that had 39,7mm comp height.
 
John V said:
Very interesting...now you know about cast iron?

Where'd you learn that? Link!

It couldn't possibly be a combination of a better wrist pin locations and longer rods and the resultant reduced tendency for side-thrust from less rod angulation, and pistons wanting to tip?

Why do you suppose everybody else in the world had gone away from pistons with compression heights in the 45-46mm range--except conservative old German Opel by the late 60s? And everything from Japan to USA to Germany and Sweden had gone to pistons with compression heights around 39,5* to 41,5mm...And by the early 80s around 35mm?
And by the 1990 around 30-32mm? Everybody..from Japan to Germany and America.

Do tell.
You have an opinion on everything, that's fine..But tell us some facts..

And you seem certain that the forged steel crankshaft that is bigger in every dimension that a Small Block Chevy crank contributed nothing, it was the rods that made the B21/b23 stout..Hmmmm Live and learn..



*Even Volvo themselves with the introduction 15 years after everybody else of the B200/B230 that had 39,7mm comp height.
Click to expand...
Yes also has a lot to do with crank steered vs piston steered rods. Again, just what I've read on here many many times.

Oh here's something else I read on here from Roy.

I am not a metallurgical engineer, I am just regurgitating what I've read on here.


2manyturbos said:
The B21s are known for running quietly with 300,000+ miles on them.
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2manyturbos said:
Piston material and nickel content in the blocks. The B21/23 engines run quiet almost forever until the bearings wear out and they start knocking. I've seen them with 450,000 miles on them running quietly. Quietly is a relative term. New, they were not a quiet engine. A 6 cylinder whiteblock is so smooth and quiet when in good shape I have accidentally tried to restart one while it was running. It was the first one I owned. A pristine 90K mile 960 sedan. I thought it has stalled after backing it up in my driveway. That was a horrible sound when the starter tried to engage the flywheel at 750 RPM. It's only happened once.
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Here's the link you asked for.
http://forums.turbobricks.com/showthread.php?t=343562
 
Longevity of b21 and adding a turbo are not the same things

Skinny rod early 230 go forever also

Seen way more b21s with a hole in the block than early b230.
 
Jack said:
Longevity of b21 and adding a turbo are not the same things

Skinny rod early 230 go forever also

Seen way more b21s with a hole in the block than early b230.
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Didn't say they won't go forever, but that doesn't mean they wear as well as a b21. Idc how many redblocks you've neglected and blown up. Makes no difference to me.

Shut up
 
Jack said:
But you say they are stout and your example is longevity and rods

Nothing was said about me blowing them up
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:uh: yes they are stout. Search any old thread on here. It takes quite a bit to kill them so whichever ones you've seen must have been neglected pretty bad. Rods help with being stout, huge big end, huuuge crank, good materials in block. What is so difficult to understand, is everything I've read on this forum a lie?
 
B21F

With a +T longevity.. show me 2 builds


What I claimed is that they weren’t good for a plus T... right or wrong I really don’t know.

The way they came from Sweden and longevity I know about. So gape that TB search engine and show me what you found inside
 
Jack said:
B21F

With a +T longevity.. show me 2 builds


What I claimed is that they weren?t good for a plus T... right or wrong I really don?t know.

The way they came from Sweden and longevity I know about. So gape that TB search engine and show me what you found inside
Click to expand...

why tf would a +t not work in the long term?? There is nothing inherently wrong with the NA block or internals. If anything they make a better DD torquey motor. Have fun with a 7.5:1 CR. Kinda sucks when not in boost.
 
SquareD said:
Oh, lets run this back. It sounds like OP wants simple bolt-ons which are easily sourced and add mid-range grunt; making his free NA, Auto 740 more fun to drive. Right now something as involved as a +T is out of the question.

OP the short answer is there is hardly any "off the shelf" support for any of these cars, turbo or NA. If a +T is out, I assume swapping in a JV sourced longblock is not going to happen.

If you want easy bolt ons, you have what you've found... basically sourcing a turbo exhaust and retrofitting it to your NA for "more flow" and the VX cam. The exhaust really won't do much, but make it a bit louder (I know because I did this to my old NA940) and the VX cam won't do a whole lot, maybe a handful of hp at specific spot on the rev range. You'll lose some low rev power, so you'll have to couple that VX with an adjustable cam gear (Yoshifab, STS Machinine and IPD all offer variations). K&N filter won't do much, especially on an NA... so really yeah that's about it.

Honestly, the biggest bang for your buck when it comes to upping enjoyment would be from suspension mods. Some sport springs, sway bars, chassis bracing and if you want fancier shocks (bilstein or koni)... Be aware though... the older you are and the further you go down that road the less you'll like DDing the car. I recommend fresh gas pressurized shocks/struts, sways and lower chassis braces for a nice handling DD, sport/lowering springs if you want to hunker it down a bit.

That's my no BS 2 cents.
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Vincent Gagnon said:
What about gearing?

it's the secret of happiness duuuuuuuuude.
Click to expand...

This thread will be closed/cleaned up soon I'm sure, but these should be the main take aways for the questions asked.
 
curiousCat said:
@Vincent Gagnon:
Thanks for the tip. Would like to know more of what you're thinking here ;-)
Click to expand...

Well, if you don't want to weld/cut/custom driveshaft etc. for the moment, you might want to consider simply swapping a manual transmission and figure out what final drive you have.

The shortest they made is 4.10.

This is simple and (I don't know where you are) but I'm pretty sure with a little bit of patience, looking in pick and pulls, craigslist and posting here in wanted, you could get what you need for cheap.

I had a 16v NA manual 4.10 740 and it would accelerate ok and was nice on the highway.

That is a reasonable fist step.

Now, if you want to go full retard, we can talk.

soclosenotnear said:
This thread will be closed/cleaned up soon I'm sure, but these should be the main take aways for the questions asked.
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Yeah, I have the same feeling.

That's what happens when anybody go against the doxa around here : put a turbo on a 300 000 000 000 000 miles engine, everything will be fine, you just need a good tune.

I don't get it.
 
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