Need your opinion. Thanks in advance

[x ReAcT x]

Im at the stage where I will be putting a new V8 in the truck and i have reached a dilemma. Either carb or EFI. Kidding of course im going EFI but this is the real predicament: Ls swap or splurge and go for the crate RAMJET 350. One of the main things im hoping for with this swap is Fuel Efficiency. With the LS swap im going to need a variety of things: engine, harness, fuel, motor mounts and transmission adapter. I have a 6000 budget and i really would like to stay in that range. I can get the entire RAMJET 350 with a serpentine system for 6K. Brand New, Never opened, ready to go. So heres some info about the truck. 1986 K1500 with SM465 and 3.42 gears. I would love to swap the transmission and gears but I made the decision to spend money to rebuild the SM465 and put a 600 posi-trac unit in the back. So i cant swap gears or tranny out. So this is where im at.. Which is easier? which is better? LS 6.0L or 5.7L RAMJET 350??

[68Stepbed]

I say the LS platform. Here's why. The RamJet engine is a great engine, with plenty of power/torque, but if you ever plan to upgrade anything later, well, you can't. The RamJet FI system is tuned for only that engine and cannot be reflashed, retuned, etc.

With the modern OBD II PCM system of the Gen III/IV(LSx) engines, all the technology is available for it for retunes/reflashes and upgrades.

Also, if you search around, you should be able to find a good 6.0 engine with PCM/ECM, harness, manifolds intake and pretty much everything you will need for under $2K. More than likely even get an engine/trans combo for that price.

The aftermarket is pushing towards the Gen III/IV market more and more also.

Check out LS1tech.com for lots of good info, and an enormous classifieds section.

[BR3W CITY]

you posted it in the Lsx section, so subliminally you WANT an ls motor.....go get one.

[Clyde65]

I dont get it, you are working on a 4x4 AND you want fuel economy? JK, JK! only way for that is going with a 5.3/4l60e out of a 4x4 truck, cam, tune etc and all that. leave the 3.42's and roll that way, imo it will give you as close as you will get to economy with a 4x4 and some muscle behind it. The 6.0 wont give you economy, HP yes.

[Jonboy]

I agree. I would sell the SM465 and go 4L60E.

[mooseknuckles]

Ls..

[ls1nova71]

The ramjet doesn't get as good of mpg as you may think. Its fuel injected, but as was stated earlier, you can't really tune it. Not to mention its basically a TPI in disguise which is almost 30 year old technology, from back when they were just figuring out EFI. The newer Ls engines are better due to the fact great strides have been made in recent years when it comes to fuel economy. That said, if that's your goal, a 5.3 would be more suited to your needs, 6.0's are thirstier!
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[Daaaanz67]

Ls all the way just got done with mine and make excuses that I have to go get something just so I can drive it hard to keep my foot out of it oh so smoooooooth.
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[68GMCCustom]

LSx..... 5.3 should meet your needs, be more economical then a 6.0... and still provide roughly 350hp for fun.

[x ReAcT x]

Originally Posted by 68Stepbed

I say the LS platform. Here's why. The RamJet engine is a great engine, with plenty of power/torque, but if you ever plan to upgrade anything later, well, you can't. The RamJet FI system is tuned for only that engine and cannot be reflashed, retuned, etc.

With the modern OBD II PCM system of the Gen III/IV(LSx) engines, all the technology is available for it for retunes/reflashes and upgrades.

Also, if you search around, you should be able to find a good 6.0 engine with PCM/ECM, harness, manifolds intake and pretty much everything you will need for under $2K. More than likely even get an engine/trans combo for that price.

The aftermarket is pushing towards the Gen III/IV market more and more also.

Check out LS1tech.com for lots of good info, and an enormous classifieds section.

I didnt realize how cheap an LSx swap would be. Wiring harness from GMPP is $800. I can get the motor for $1000 from my friend (serpentine system included). The tanny adapter is probably $800 im assuming?? Get a holley fuel regulator and holley external fuel pump for $50 and $150 respectively. But what about the clutch and flywheel i cant find any info on them...

[x ReAcT x]

Originally Posted by BR3W CITY

you posted it in the Lsx section, so subliminally you WANT an ls motor.....go get one.

Hahaha I guess i made it too obvious

[x ReAcT x]

Originally Posted by Clyde65

I dont get it, you are working on a 4x4 AND you want fuel economy? JK, JK! only way for that is going with a 5.3/4l60e out of a 4x4 truck, cam, tune etc and all that. leave the 3.42's and roll that way, imo it will give you as close as you will get to economy with a 4x4 and some muscle behind it. The 6.0 wont give you economy, HP yes.

Yea fuel economy in a 4x4 is like asking for ice water in hell but i figured if im going to spend 6k for a daily driver i better make it worthwhile. The only thing is i want a manual. and since ive already spend money to rebuild the stupid sm465 im going to have to keep it. Should have just went with the NV4500....

[x ReAcT x]

Originally Posted by Jonboy

I agree. I would sell the SM465 and go 4L60E.

That definitely makes the most sense but i want a manual

[68Stepbed]

Originally Posted by x ReAcT x

I didnt realize how cheap an LSx swap would be. Wiring harness from GMPP is $800. I can get the motor for $1000 from my friend (serpentine system included). The tanny adapter is probably $800 im assuming?? Get a holley fuel regulator and holley external fuel pump for $50 and $150 respectively. But what about the clutch and flywheel i cant find any info on them...

Google is your friend.
http://www.google.com/#hl=en&gs_nf=1...w=1152&bih=696

[BR3W CITY]

actually the prices you posted seem kinda high for that stuff....

[x ReAcT x]

Originally Posted by 68Stepbed

Google is your friend.
http://www.google.com/#hl=en&gs_nf=1...w=1152&bih=696

Haha I have been looking for that advcanced adapters piece forever through google guess i just didnt work it right. thanks for the link

[x ReAcT x]

I was thinkin of just buying the 5.3 engine from turnkeyenginesupply.com
They have raving reviews from respected sources. These are the only ones that arent blocked through my proxy at work but:
http://www.truckinweb.com/tech/1204t...s/viewall.html
http://www.knfilters.com/news/news.aspx?ID=1170


and now for the downside 7000.00 excluding shipping....

[BR3W CITY]

didn't anyone say
car-part.com yet?

i swear 80% of people (aka everyone who didn't already have a full donor, or buy a "Ready to run" engine) get swap stuff this way.
15min on car-part, a few phone calls and a trip to a salvage yard goes pretty far in getting what you need.

[whitels1]

Originally Posted by x ReAcT x

One of the main things im hoping for with this swap is Fuel Efficiency.

LS all the way, I just did this swap into my 81 K5 / SM465, I spent less than 6k, and I had to completely rebuild my engine. http://67-72chevytrucks.com/vboard/s...d.php?t=532351. Drives like a dream!

[x ReAcT x]

Originally Posted by whitels1

LS all the way, I just did this swap into my 81 K5 / SM465, I spent less than 6k, and I had to completely rebuild my engine. http://67-72chevytrucks.com/vboard/s...d.php?t=532351. Drives like a dream!

You did a great write up for that thread, very detailed. Ill be refering to that every now and then to point me in the right direction. How did you get the sm465 to mount to the 5.3L? did you use AA?

[x ReAcT x]

I appreciate everyones input and im going with the 5.3L/SM465. Your right it just makes sense to upgrade to LS. So this is what im buying will be putting it in when i get it in the mail.
5.3L E-ROD CRATE ENGINE 6189.95
http://paceperformance.com/i-7542625...nsmission.html
ADVANCE ADAPTER LS TO SM465 627.21
http://www.advanceadapters.com/products/pn-712500m/
DIRTY DINGO ENGINE ADAPTER MOUNTS POWDERCOATED
http://dirtydingo.com/store/product_...oducts_id=1308

Well ended up going about 1000.00 over my budget but with a few more parts this should be a relatively easy swap. Nearly turn key

[whitels1]

Originally Posted by x ReAcT x

I appreciate everyones input and im going with the 5.3L/SM465. Your right it just makes sense to upgrade to LS. So this is what im buying will be putting it in when i get it in the mail.
5.3L E-ROD CRATE ENGINE 6189.95
http://paceperformance.com/i-7542625...nsmission.html
ADVANCE ADAPTER LS TO SM465 627.21
http://www.advanceadapters.com/products/pn-712500m/
DIRTY DINGO ENGINE ADAPTER MOUNTS POWDERCOATED
http://dirtydingo.com/store/product_...oducts_id=1308

Well ended up going about 1000.00 over my budget but with a few more parts this should be a relatively easy swap. Nearly turn key

That's a lot of money on the clutch set up, you could use your old clutch and an NFW1050 flywheel/LS7 pilot bearing with no problems and it would save you big time. The Engine should be a sweet running machine!