The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Engine & Drivetrain > Diesel Conversions

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 01-26-2014, 09:17 PM   #1
MYBAD66
Registered User
 
MYBAD66's Avatar
 
Join Date: Oct 2013
Location: Las Vegas, Nevada
Posts: 79
4bt cummins swap

Hey all I know this is probably a quite popular topic but I'm looking to put a 4bt cummins in the 66 with an sm465 tranny maybe put in dana 40 4.10 geared rear end is there anything in particular I should consider? Cutting the firewall frame etc.
__________________
94 Chevy K1500 350
66 GMC c2500 305
MYBAD66 is offline   Reply With Quote
Old 01-26-2014, 09:46 PM   #2
1972RedNeck
Registered User
 
1972RedNeck's Avatar
 
Join Date: Jan 2011
Location: Townsend MT
Posts: 1,725
Re: 4bt cummins swap

If you get one with a Chevy adapter plate an flywheel, it will mate right to a tranny from behind an inline 6/sbc/bbc.

The firewall and frame are fine.

It would be pretty cool to see a 478 toro-flow under the hood. It should bolt right in too.
__________________
1966 F250 4X4 416
1972 K20 350 4 OTF
Quote:
Originally Posted by GASoline71 View Post
I once pulled an intake manifold for a cam swap... ended up with a full on drag car that ran in the 11's.
1972RedNeck is offline   Reply With Quote
Old 01-26-2014, 09:51 PM   #3
1972RedNeck
Registered User
 
1972RedNeck's Avatar
 
Join Date: Jan 2011
Location: Townsend MT
Posts: 1,725
Re: 4bt cummins swap

Name:  DSCN1391.jpg
Views: 17368
Size:  66.4 KB
__________________
1966 F250 4X4 416
1972 K20 350 4 OTF
Quote:
Originally Posted by GASoline71 View Post
I once pulled an intake manifold for a cam swap... ended up with a full on drag car that ran in the 11's.
1972RedNeck is offline   Reply With Quote
Old 01-27-2014, 11:41 AM   #4
kieth
Registered User
 
kieth's Avatar
 
Join Date: Sep 2010
Location: Tulsa, Oklahoma
Posts: 1,925
Re: 4bt cummins swap

Anyone know the spec's on this engine (hp) max rpm, peak torque. Looks like it would get better fuel mileage with a OD transmission instead a stock 4 speed granny. how about a NV3500 or NV4500.....????they should handle the diesel torque......I always shoot for 65mph at 1800rpm on a diesel engine....someone get me the specs on the engine and I will work up the performance information. Kieth


I looked up the spec's and this little engine will perform rather well, it has the torque performance of a 327 4 barrel engine but is only rated at 2300rpm with peak torque at 1600 rpm. Looks like it needs a transmission with very close gear ratio spacing to keep from falling off its torque curve. Will review and look for a good transmission for this engine........Kieth

105hp@2300 peak torque 265ft/lbs@1600 rpm

Last edited by kieth; 01-27-2014 at 12:00 PM.
kieth is offline   Reply With Quote
Old 01-27-2014, 04:14 PM   #5
TJ's Chevy
Registered User
 
TJ's Chevy's Avatar
 
Join Date: Mar 2013
Location: Southern Oregon
Posts: 10,384
Re: 4bt cummins swap

I know this is big an bulky an expensive....but a Richmond 6 speed will give you 5 direct gears and a 6th gear od. It is pretty close ratio.
__________________
1966 Chevy C10 "Project Two Tone" http://67-72chevytrucks.com/vboard/s...d.php?t=596643
1964 GMC "Crustine" semi-build:http://67-72chevytrucks.com/vboard/s...d.php?t=665056
My youtube channel. Username "Military Chevy": https://www.youtube.com/channel/UC_h...fzpcUXyK_5-uiw
TJ's Chevy is offline   Reply With Quote
Old 01-28-2014, 12:33 AM   #6
Peanutbutter
Account Suspended
 
Join Date: Feb 2013
Location: Mesa, Colorado
Posts: 450
Re: 4bt cummins swap

Quote:
Originally Posted by MYBAD66 View Post
Hey all I know this is probably a quite popular topic but I'm looking to put a 4bt cummins in the 66 with an sm465 tranny maybe put in dana 40 4.10 geared rear end is there anything in particular I should consider? Cutting the firewall frame etc.
Hi, I have a 90 1500 swb 4x4, 4bta with 4500 and 342 gears. To do this swap I would not use the 3500 trans, only the 4500 with around 3.42 gears and remember if you use the GM bread truck block to bellhousing adapter you will either have to cant the motor or the trans I think 7 degrees. We normally get 25 to 28 mpg, one time we got 34 in mass, checked the figures 3 times and came out the same. One time we pulled our smaller two axle fifthwheel camp trailer about 100 miles with no negative effects running 55 to 60 mah. Our truck has at least 400K on the 4bt and never been touched. Getting ready to put one in our blazer chalet.
Peanutbutter is offline   Reply With Quote
Old 01-28-2014, 06:23 PM   #7
dieseldude4bt
Registered User
 
Join Date: Mar 2011
Location: Co
Posts: 412
Re: 4bt cummins swap

Hey Peanutbutter, I know who you are.
The Dodge diesel NV4500 or even the Getrag G360 would be a good option and wil bolt right up with the Dodge parts.
I run the original SM420 with a Ranger overdrive, have no problems with it and it gives me more gear options for my heavy truck when towing.
I average 24 mpg in combined driving in a 6300lb 3/4 ton 4x4 and have got as goood as 30 on a trip to Denver.
__________________
63 k20 with cummins 4bt, owned sence 1982
dieseldude4bt is offline   Reply With Quote
Old 02-03-2014, 11:41 PM   #8
ky-donzi
Registered User
 
Join Date: Jun 2012
Location: madisonville ky
Posts: 313
Re: 4bt cummins swap

I've got a 4bta in a 61 gmc 4x4. I used a late model frame, it makes getting parts easy. I love mine. Dieseldude helped me a lot on my build. Unless you go with a add on OD drop the 4 sp and look for a 5 or 6 speed.

Don't let the numbers fool you they have all kinds of power! Enough to rip gas componates apart
__________________
61 GMC 4x4 1-ton flatbed 4bt cummins, ranger od, sm465, np 205, d60F, d70R 4.11 10,000 ramsey PTO winch.... SOLD

73 k5 gm crate 350-265 / sm465 / np205 3.73 posi
ky-donzi is offline   Reply With Quote
Old 02-04-2014, 01:29 AM   #9
argonaut
Senior Member
 
argonaut's Avatar
 
Join Date: Aug 2008
Location: Long Beach, CA
Posts: 1,813
Re: 4bt cummins swap

Guys I'm intrigued by the 4bt swap. How does it stack up against a big block for power? Obviously it gets double the mileage. I had considered a 6bt but it looks like they're big and heavy and hard to make fit. Sorry if I'm thread jacking!
__________________
Jason M. @argonaut62

1972 K5 Blazer CST, Turquoise
1966 K20 Short Fleet Pickup, Big Ugly
1964 C10 Short Fleet, Gertrude

2001 Porsche 911 Carrera
1996 Ford Bronco XLT
1980 Jeep Wagoneer

2008 Honda CBR1000RR
2005 Honda RC51
1981 Honda CB750C


No dis-assemble Johnny Five! No dis-assemble!
argonaut is offline   Reply With Quote
Old 02-04-2014, 09:57 AM   #10
ky-donzi
Registered User
 
Join Date: Jun 2012
Location: madisonville ky
Posts: 313
Re: 4bt cummins swap

I would say my 4bt (pump is turned up and different turbo) is somewhere in between a hot SBC and a mild BBC. There is a big difference tho, until you drive a diesel you cant really understand what I mean. Even tho my engine probably puts out 400-420 ft/lb, but at 1600-1800 rpm. The HP is very low, so it doesn't feel like driving a BBC until you hook a trailer to it.... IDK if Im making sense.
__________________
61 GMC 4x4 1-ton flatbed 4bt cummins, ranger od, sm465, np 205, d60F, d70R 4.11 10,000 ramsey PTO winch.... SOLD

73 k5 gm crate 350-265 / sm465 / np205 3.73 posi
ky-donzi is offline   Reply With Quote
Old 02-04-2014, 01:26 PM   #11
dieseldude4bt
Registered User
 
Join Date: Mar 2011
Location: Co
Posts: 412
Re: 4bt cummins swap

^^2x what he said.
__________________
63 k20 with cummins 4bt, owned sence 1982
dieseldude4bt is offline   Reply With Quote
Old 02-04-2014, 02:09 PM   #12
jmack91z28
Registered User
 
jmack91z28's Avatar
 
Join Date: Oct 2012
Location: Midland NC
Posts: 118
Re: 4bt cummins swap

My opinion is this isn't a popular topic, at least not here.

My 6BT with NV4500 in my dodge is the slowest thing i've ever owned/driven. Gets good mileage, about 18 mpg average. Pulls decent. My old 94 chevy with a 454 pulled way better but at the cost of 8 mpg... Parts are far more expensive, my (indestructible P pump) injection pump went out last year, costed me $2200 for a rebuild. You can build a nice small block for that much.

I dunno, I don't buy into the cummins hype even though I own one. A swap would be very expensive, around 6-8 thousand? You can buy a lot of gasoline for that, years and years and years of gasoline.

4BT's aren't balanced, so they'll rattle your teeth at idle. I've seen many a 4bt swap that ultimately ended in the owner selling the vehicle because of the harmonics and vibrations.

You want good mileage and torque, and affordability? Why not an older stovebolt 261 or so. It'll produce more power than a 4bt at less weight and costs and with fuel that costs 50 to 70 cents cheaper a gallon.

Just my opinion and experience on it.
__________________
1961 C60 Viking 8' Dump 261 SM420 2-Speed Rear
1966 C10 Fleetside 350 W/ Saginaw 4 speed
1985 K10 Chevy 6.2 diesel 700r4 longbed
2001 Dodge 3500 Dually 24v NV5600 4x4
USMC Reserves
Jason
jmack91z28 is offline   Reply With Quote
Old 02-04-2014, 03:09 PM   #13
ky-donzi
Registered User
 
Join Date: Jun 2012
Location: madisonville ky
Posts: 313
Re: 4bt cummins swap

Jmack

I agree with a lot that you a have said except for

"You want good mileage and torque, and affordability? Why not an older stovebolt 261 or so. It'll produce more power than a 4bt at less weight and costs and with fuel that costs 50 to 70 cents cheaper a gallon."

I doubt that a 261 would pull anywhere near as well as my 4bt, nor get the mileage.
__________________
61 GMC 4x4 1-ton flatbed 4bt cummins, ranger od, sm465, np 205, d60F, d70R 4.11 10,000 ramsey PTO winch.... SOLD

73 k5 gm crate 350-265 / sm465 / np205 3.73 posi
ky-donzi is offline   Reply With Quote
Old 02-04-2014, 04:07 PM   #14
jmack91z28
Registered User
 
jmack91z28's Avatar
 
Join Date: Oct 2012
Location: Midland NC
Posts: 118
Re: 4bt cummins swap

No, you're right, it wouldn't get near as good as mileage as a 4bt. But when you factor in cost difference in fuel, it's not quite as good a deal you know? For the money and time spent that is.

I think a 261 or 292 will put out as much torque as an old 4bt, and a lot more hp. But then it has to do with where the two engines are making torque, how the truck is geared, transmission, etc.

My 6bt doesn't feel like it's really making any power till about 1700 rpm, then after 2300 rpm it's basically making a bunch of noise and not doing anything haha. So you've got such a small powerband. I know you can mess with the governer spring and all that fun stuff in the IP and "turn the fuel up", but I just haven't yet.

A good running stovebolt with a newer style HEI ignition and the such, coupled with a 5 or 6 speed, geared correctly should produce respectable power numbers, tow what you'd need within reason and probably get 20 mpg highway.

I'm not knocking the cummins option, just giving an alternate view.
__________________
1961 C60 Viking 8' Dump 261 SM420 2-Speed Rear
1966 C10 Fleetside 350 W/ Saginaw 4 speed
1985 K10 Chevy 6.2 diesel 700r4 longbed
2001 Dodge 3500 Dually 24v NV5600 4x4
USMC Reserves
Jason
jmack91z28 is offline   Reply With Quote
Old 02-04-2014, 04:18 PM   #15
TJ's Chevy
Registered User
 
TJ's Chevy's Avatar
 
Join Date: Mar 2013
Location: Southern Oregon
Posts: 10,384
Re: 4bt cummins swap

A stock 292 inline 6 makes 153 HP and 265 Pound feet of torque...these motors were lucky if they were getting 15 miles per gallon. I am not sure if your 4bt is turbo charged are not...I forgot. lol. Anyhow, If you turbo stock 292 to 8 pounds of boost your power will increase to around 300 hp and over 300 pound feet of torque...a 261 is not the best motor for 1...parts are scarce...2 trying to find performance parts are nearly impossible. If you were going to do a 6 cylinder a 250 or 292 would be your best bet. Note that many parts aren't interchangeable between the two...a 292 crank will fit a 250..or a 250 head on a 292. The 292 will get much better rpm rang then your cummins will...I can rev my 292 to 4,500 rpm between shifts...and the bottom end is stock...but my carb and manifolds and ignition aren't. The 292 peaks torque around 1,600-2,000 rpm...and hp around 4,000 according to factory. Now if you do a 6bt 5.9 turbo cummins you'll put us all to shame! LOL!
__________________
1966 Chevy C10 "Project Two Tone" http://67-72chevytrucks.com/vboard/s...d.php?t=596643
1964 GMC "Crustine" semi-build:http://67-72chevytrucks.com/vboard/s...d.php?t=665056
My youtube channel. Username "Military Chevy": https://www.youtube.com/channel/UC_h...fzpcUXyK_5-uiw

Last edited by TJ's Chevy; 02-04-2014 at 04:26 PM.
TJ's Chevy is offline   Reply With Quote
Old 02-04-2014, 04:56 PM   #16
jmack91z28
Registered User
 
jmack91z28's Avatar
 
Join Date: Oct 2012
Location: Midland NC
Posts: 118
Re: 4bt cummins swap

Quote:
Originally Posted by T.J. MCCAULEY View Post
A stock 292 inline 6 makes 153 HP and 265 Pound feet of torque...these motors were lucky if they were getting 15 miles per gallon. I am not sure if your 4bt is turbo charged are not...I forgot. lol. Anyhow, If you turbo stock 292 to 8 pounds of boost your power will increase to around 300 hp and over 300 pound feet of torque...a 261 is not the best motor for 1...parts are scarce...2 trying to find performance parts are nearly impossible. If you were going to do a 6 cylinder a 250 or 292 would be your best bet. Note that many parts aren't interchangeable between the two...a 292 crank will fit a 250..or a 250 head on a 292. The 292 will get much better rpm rang then your cummins will...I can rev my 292 to 4,500 rpm between shifts...and the bottom end is stock...but my carb and manifolds and ignition aren't. The 292 peaks torque around 1,600-2,000 rpm...and hp around 4,000 according to factory. Now if you do a 6bt 5.9 turbo cummins you'll put us all to shame! LOL!
Yeah that's all pretty much accurate. A 261 would produce about 150HP at 2,000 and 230 ft lb at about 4,000.

What transmission and rear end are you running in your truck TJ?
__________________
1961 C60 Viking 8' Dump 261 SM420 2-Speed Rear
1966 C10 Fleetside 350 W/ Saginaw 4 speed
1985 K10 Chevy 6.2 diesel 700r4 longbed
2001 Dodge 3500 Dually 24v NV5600 4x4
USMC Reserves
Jason
jmack91z28 is offline   Reply With Quote
Old 02-04-2014, 06:12 PM   #17
TJ's Chevy
Registered User
 
TJ's Chevy's Avatar
 
Join Date: Mar 2013
Location: Southern Oregon
Posts: 10,384
Re: 4bt cummins swap

Quote:
Originally Posted by jmack91z28 View Post
Yeah that's all pretty much accurate. A 261 would produce about 150HP at 2,000 and 230 ft lb at about 4,000.

What transmission and rear end are you running in your truck TJ?
You mean 150 HP at 4,000 rpm and 230 ft lbs 2,000. I am running the stock transmission( 4 speed on the floor) and the stock C-10 axle. GM 12 bolt rear axle...gear ratio probably 3.90 or 4.11. The only reason I rev it to 4,000+ between shifts is the rpm travel between shifts...2nd to 3rd is almost a 2,000 rpm split..if I was to rev it to 4,000 in 2nd then shift to 3rd my rpms would start just around 2,000 rpm....3rd to 4th is worse, But hey...these weren't made for speed. lol...which I am going to change to a richmond 6 speed...5 direct gears and a 6th gear overdrive. Spendy, but worth it.
__________________
1966 Chevy C10 "Project Two Tone" http://67-72chevytrucks.com/vboard/s...d.php?t=596643
1964 GMC "Crustine" semi-build:http://67-72chevytrucks.com/vboard/s...d.php?t=665056
My youtube channel. Username "Military Chevy": https://www.youtube.com/channel/UC_h...fzpcUXyK_5-uiw
TJ's Chevy is offline   Reply With Quote
Old 02-04-2014, 06:38 PM   #18
jmack91z28
Registered User
 
jmack91z28's Avatar
 
Join Date: Oct 2012
Location: Midland NC
Posts: 118
Re: 4bt cummins swap

Quote:
Originally Posted by T.J. MCCAULEY View Post
You mean 150 HP at 4,000 rpm and 230 ft lbs 2,000. I am running the stock transmission( 4 speed on the floor) and the stock C-10 axle. GM 12 bolt rear axle...gear ratio probably 3.90 or 4.11. The only reason I rev it to 4,000+ between shifts is the rpm travel between shifts...2nd to 3rd is almost a 2,000 rpm split..if I was to rev it to 4,000 in 2nd then shift to 3rd my rpms would start just around 2,000 rpm....3rd to 4th is worse, But hey...these weren't made for speed. lol...which I am going to change to a richmond 6 speed...5 direct gears and a 6th gear overdrive. Spendy, but worth it.
Yeah, my fault haha.
__________________
1961 C60 Viking 8' Dump 261 SM420 2-Speed Rear
1966 C10 Fleetside 350 W/ Saginaw 4 speed
1985 K10 Chevy 6.2 diesel 700r4 longbed
2001 Dodge 3500 Dually 24v NV5600 4x4
USMC Reserves
Jason
jmack91z28 is offline   Reply With Quote
Old 02-04-2014, 06:55 PM   #19
dieseldude4bt
Registered User
 
Join Date: Mar 2011
Location: Co
Posts: 412
Re: 4bt cummins swap

4bt vibrations are over exagerated, I have 3 trucks with them and they vibrate no worse than a lot of the 6.2L trucks I have driven.
I also have 4.10 gears and the sm420 and I don't have to rev to 4000 rpm between shifts so there must be a large differance in toque down low between it and a 261.
__________________
63 k20 with cummins 4bt, owned sence 1982
dieseldude4bt is offline   Reply With Quote
Old 02-04-2014, 07:54 PM   #20
ky-donzi
Registered User
 
Join Date: Jun 2012
Location: madisonville ky
Posts: 313
Re: 4bt cummins swap

If the diesel thing bothers you, you can get good numbers out of the newer LS
style engines. They would give good mpg, and power...

I can't stand computer controlled engines tho... This was the biggest appeal to me... My 4bt is completely mechanical...

It doesn't require any electrical connections at all. Matter of fact, if you push it hard enough it will start and take off down the street.
__________________
61 GMC 4x4 1-ton flatbed 4bt cummins, ranger od, sm465, np 205, d60F, d70R 4.11 10,000 ramsey PTO winch.... SOLD

73 k5 gm crate 350-265 / sm465 / np205 3.73 posi
ky-donzi is offline   Reply With Quote
Old 06-25-2014, 02:18 PM   #21
BigSix
Registered User
 
Join Date: Mar 2014
Location: MD/VA/PA Or Inbetween
Posts: 413
Re: 4bt cummins swap

Quote:
Originally Posted by dieseldude4bt View Post
Hey Peanutbutter, I know who you are.
The Dodge diesel NV4500 or even the Getrag G360 would be a good option and wil bolt right up with the Dodge parts.
I run the original SM420 with a Ranger overdrive, have no problems with it and it gives me more gear options for my heavy truck when towing.
I average 24 mpg in combined driving in a 6300lb 3/4 ton 4x4 and have got as goood as 30 on a trip to Denver.
dieseldude - with the ranger overdrive how did your sticks work out? Is there room in front of the bench to put the SM420 stick still?
BigSix is offline   Reply With Quote
Old 06-25-2014, 04:52 PM   #22
dieseldude4bt
Registered User
 
Join Date: Mar 2011
Location: Co
Posts: 412
Re: 4bt cummins swap

The 420 stick moves back 7 1/2 inches and the ranger stick is to the left and in front of that. as is my transfer case stick.
__________________
63 k20 with cummins 4bt, owned sence 1982
dieseldude4bt is offline   Reply With Quote
Old 06-25-2014, 07:05 PM   #23
66LSx
Registered User
 
66LSx's Avatar
 
Join Date: Nov 2013
Location: Green Bay, WI
Posts: 435
Re: 4bt cummins swap

The 4BT.....

gobs of torque, fuel efficiency, and even a bit of noise on the side....

It won't go anywhere fast..... but it'll keep going and going.....

I know a few things about that motor.....and its big brother 6BT....

(my last project 1947 Ford 1.5 Ton on hydroboosted disc brake, 4 link air suspension)





__________________
1966 C10 SWB Fleet
5.3L LM7 Vortec / 4L60e Swap
1966 C10 w/ 5.3L/4L60e Build Thread
2012 GMC Sierra 5.3L 4x4 CCSB
66LSx is offline   Reply With Quote
Old 06-25-2014, 08:44 PM   #24
61_FL_Apache
Who Me?
 
61_FL_Apache's Avatar
 
Join Date: Sep 2010
Location: Royal Palm Beach, FL
Posts: 4,067
Re: 4bt cummins swap

That looks like a cool project!!
__________________
Steve

1997 Tahoe LT 4D 2WD (DD)
2001 Blazer 4D 2WD
1961 Apache 10 (sold)
1965 C10 Stepper (sold)
61_FL_Apache is offline   Reply With Quote
Old 06-25-2014, 11:33 PM   #25
66Submarine
Registered User
 
66Submarine's Avatar
 
Join Date: Sep 2012
Location: Dallas, GA
Posts: 1,497
Re: 4bt cummins swap

I'll have to agree that the light duty Cummins diesel thing was also a little bit of a letdown to me when I really looked into it. Still cool, but not nearly as cool as it looked at a glance.

TJ; FWIW, your truck should have 3.73 gears. 3.90 was the earlier (pre '63) Eaton ratio. Could have 4.11's, but I doubt it.

I'll also add that IME/IMO 4,000RPM is a really excessive shift point for normal driving with the SM420/inline six. I have a weaker 250 in my one ton and normally shift @ something like 2,200-2,500RPM (most of the time). It's certainly not necessary.

FWIW, 292 GM spec is (net) 153HP @ 3,600RPM and 255ftlbs @ 2,400RPM in '65. (I'll post the dyno sheet as an attachment).

So, (in stock form) the 4BT and 292 will probably pull similarly up to 2,000RPM or so, but the 292 will have another 50HP available higher up. That ability to wind it up a little and get half again as much power is kind of nice...
Attached Images
 
__________________
1965 C30 pickup 350/SM420/4.10's (daily driver) thread
1968 Impala 4 door sedan (future driver project) thread
66Submarine is offline   Reply With Quote
Reply

Bookmarks


Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 06:55 PM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com