700r4 /4.10 rear/350 engine in 72 c20 sound good?

[Signkutter]

The motor is a recent rebuild and is equipped with the Edelbrock EZ efi , Edelbrock Performer airgap intake, Edelbrock 2117 cam and 60909 Performer heads.

Don't know what this engine should be pushing torque or HP...I was told the motor was good for 350hp and around 400 tq peak power. How does set sound for a 72 2wd LB C20? Don't need a hot rod but it does need to have enough to pass with authority and not strain with 1k lbs in the bed

[A1971Blazer]

The 4.10 gear will bring it alive....and still have a decent highway manners with the OD....what size tires?

[Signkutter]

Originally Posted by A1971Blazer

The 4.10 gear will bring it alive....and still have a decent highway manners with the OD....what size tires?

265/70 R16 all the way around.

[Signkutter]

Reason I ask us because I have the opportunity to buy a 6.0l LQ4 chevy engine with about 100 k miles on it ...and I'm wondering if it would be an improvement over this 350 in power/performance

[A1971Blazer]

Originally Posted by Signkutter

Reason I ask us because I have the opportunity to buy a 6.0l LQ4 chevy engine with about 100 k miles on it ...and I'm wondering if it would be an improvement over this 350 in power/performance

You'll get all kinds of different responses to that question....some owners are "old school" all the way and the term "LS swap" is sacrilegious....other hold to the "latest and greatest" maxim....but undeniably....the computer controlled engine will be far superior in terms of both performance and economy....the downfall...the swap can become more expensive than simply sticking with an "original" style powertrain... (just my 2¢)

[Signkutter]

Originally Posted by A1971Blazer

You'll get all kinds of different responses to that question....some owners are "old school" all the way and the term "LS swap" is sacrilegious....other hold to the "latest and greatest" maxim....but undeniably....the computer controlled engine will be far superior in terms of both performance and economy....the downfall...the swap can become more expensive than simply sticking with an "original" style powertrain... (just my 2¢)

thanks for the insight...your are spot on about the swap cost...its not simply plug n play.

[jocko]

I'm assuming your C20 already has a 4.10 in it, yes? 4.10 is a good gear for a C20. What was your original trans? Note that a 700R4 doesn't just give you lower highway rpms, it has a deeper first gear than most 3-speed automatics as well - so, in 1st gear, a 4.10/700R4 is approximately the same as a 4.98/TH350... If you've ever driven a 4.88 or 5.14 with an older trans, well, you get the idea. So, if you plan to do any hauling or camper-ing, etc, (or hauling 1000 lbs regularly) I'd want that 700R4 a little beefed up personally. Especially if you plan to ever floor it from a dead stop (ala the 4.98 comparison.. can and will damage the weak link, whatever that happens to be - u joint, trans, etc)
Don't forget you'll need a means of locking up the torque converter in o/d and that line pressure setup is critical before running (recommend EZ-TV thing from Bowtie Overdrives. They are also a wealth of good info, even just on the website).

With that tire and 4.10s, here are your 1st gear torque multiplication and cruising rpm comparisons to a TH350 and TH400:

[Signkutter]

Originally Posted by jocko

I'm assuming your C20 already has a 4.10 in it, yes? 4.10 is a good gear for a C20. What was your original trans? Note that a 700R4 doesn't just give you lower highway rpms, it has a deeper first gear than most 3-speed automatics as well - so, in 1st gear, a 4.10/700R4 is approximately the same as a 4.98/TH350... If you've ever driven a 4.88 or 5.14 with an older trans, well, you get the idea. So, if you plan to do any hauling or camper-ing, etc, (or hauling 1000 lbs regularly) I'd want that 700R4 a little beefed up personally. Especially if you plan to ever floor it from a dead stop (ala the 4.98 comparison.. can and will damage the weak link, whatever that happens to be - u joint, trans, etc)
Don't forget you'll need a means of locking up the torque converter in o/d and that line pressure setup is critical before running (recommend EZ-TV thing from Bowtie Overdrives. They are also a wealth of good info, even just on the website).

With that tire and 4.10s, here are your 1st gear torque multiplication and cruising rpm comparisons to a TH350 and TH400:

A very informative post Jocko , thanks. What are the problems that arise if the torque converter isn't locked in o/d?

[skytop]

I had to make the same rear end axle ratio decision with my 700R4 with 20"/35 tires. After many years of having 4.11 gears, I decided it was a better decision to go with the 3.70 gear set. I am not street racing and 4.10's are too aggressive.

The 3.70's are still definitely lively but brings down highway RPM quite a bit for less noise and wear on engine and myself.

[Big Kev-O]

When the torque converter is "locked up" the transmission is in a mechanically coupled with the motor. Minimal/No heat is generated.

***When the converter is in an unlocked (disengaged) state, there is going to be some loss (slip) across the converter during almost all driving situations because of converter slip. The results of this loss or slip is work heat generated into the transmission fluid.***

Hot trannys die.

I have a 68 C20 with Crate 350, mild comp cam, 700R4, Bowtie overdrive EZ-TV kit, Switch activated manual electronic lock up. My truck easily pulls my 4700 lb. boat up steep grades. Smokes tires for days and has nice low RPMs at highway speeds.

I installed the motor,camshaft, trans, EZ-TV kit. After dialing in the carb and all the other work I now believe it would have been just as easy to get a LQ9 with 4L80E. You can get a "3 wire" harness and ecu ready to go. Wham bam thank you mam, no carb nonsense, 6.0L power and Mpg. I may have saved $500 going the 350 route. Wish I would have listened to friends and grabbed a 6.0 from wrecker.


***This info is borrowed from the Bowtie overdrives website.Link below.

http://700r4.com/faq/whatlock.shtml

[Signkutter]

Originally Posted by Big Kev-O

When the torque converter is "locked up" the transmission is in a mechanically coupled with the motor. Minimal/No heat is generated.

***When the converter is in an unlocked (disengaged) state, there is going to be some loss (slip) across the converter during almost all driving situations because of converter slip. The results of this loss or slip is work heat generated into the transmission fluid.***

Hot trannys die.

I have a 68 C20 with Crate 350, mild comp cam, 700R4, Bowtie overdrive EZ-TV kit, Switch activated manual electronic lock up. My truck easily pulls my 4700 lb. boat up steep grades. Smokes tires for days and has nice low RPMs at highway speeds.

I installed the motor,camshaft, trans, EZ-TV kit. After dialing in the carb and all the other work I now believe it would have been just as easy to get a LQ9 with 4L80E. You can get a "3 wire" harness and ecu ready to go. Wham bam thank you mam, no carb nonsense, 6.0L power and Mpg. I may have saved $500 going the 350 route. Wish I would have listened to friends and grabbed a 6.0 from wrecker.


***This info is borrowed from the Bowtie overdrives website.Link below.

http://700r4.com/faq/whatlock.shtml

I am in the same boat, brother told me to go 6.0l 4L80E and forget the 350...hind sight