texas4x4rebel
1/2 ton status
What are your plans for the K5 is it just a DD or wheeler both?
CK5
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BBC vs LS#/X Need Advice Please
- Thread starter cliles
- Start date
He needs the single serpentine setup from the 88-up C-K trucks, not the R-V that he has now. They use both V-belt and serpentine.
wayne
3/4 ton status
Correct me if I am wrong, but you have a 90 correct? You should have a 700r4 trans. Both of my 90's had 700r4's. Anyhow, go with the LS engine. You can do a mild LS and have more power then you will ever need. If you go with the RJ or any other bigblock figure on changing your trans or serious beef up of the trans you have now. Even the LS will need a good trans behind it.
Semi-daily driver, mud/rock on occasions, general truck duty so I can move back to a fast car and drop the pile 2011 dodge hemi
I thought the 90's had the 4L60e, could be wrong, but either way f##k the transmission, if it can't hang then I'll find something that can. The whole point of this post is because I worry I will end up with either a 14 mpg low torque LSX or a 10 mpg BBC. I am trying to have it all, and if I can't, I'll choose the neck breaking torque every time.
I thought the 90's had the 4L60e, could be wrong, but either way f##k the transmission, if it can't hang then I'll find something that can. The whole point of this post is because I worry I will end up with either a 14 mpg low torque LSX or a 10 mpg BBC. I am trying to have it all, and if I can't, I'll choose the neck breaking torque every time.
y5mgisi
1 ton status
Boy that is a tough one! As much of advocate of the Lsx that i am, the Ram Jet 502 would be pretty bad ass!
A 90 K5 has the single serp set-up...
'87 is the bastard year with a serp belt and V-belts. I have one of those sitting here too.
As for "low torque" LSX...I've driven my buddy's 2011 GMC quad cab with the 5.3. It's stock, and of course it weighs well over 5000 lbs and it has a ton of balls. Even with a higher tq peak the LSX is gonna be a very snappy/torquey motor IMO. That and you get the latest FI/timing/fuel management vs the archaic set-up the Ram-Jet comes with.
texas4x4rebel
1/2 ton status
Well my vote is for a ls motor, I have a 5.3 in my k5 and love it couple weeks ago I went out with it and never had any issues and it had plenty of power stock.
If I had the money I would do a custom built Ls 408stroker do some research on those.
If I had the money I would do a custom built Ls 408stroker do some research on those.
Going to have to go with the ls seires motor due to the my 00 gmc runs, got a 4.8 going in my 86 when I have time to get it swapped.
i didn't get a chance to read thru the thread completely, but i am a huge lsx fan, i've seen these motors do things that it would take multiple different engine combo to get what you can do with an lsx, if you learn how to tune you can get a multi tune ecm built that will hold, a fuel saving, towing and a balls to the wall tune all at the flip of a switch. you can use a stock computer and get just as good of results as you can with a completely aftermarket program. Every one is making every different kind of aftermarket performance product there is for them. they are the new SBC with 10x the engineering, a stock crank can handle 1000hp all day, there are an unlimited number of ways to build these motors from screaming 12,000rpm lightweight small displacment, to a 454 blown 1500hp + monster. just my .02
You are correct about the '90 being a serpentine, but '87 isn't the only year with the V belts, and the single serpentine belt on the alternator. I believe 1985 is the first year for that setup, although it may be earlier, and that setup was used through 1988.
Martin
I was under the impression that the R/V trucks carried over the dual belt thingy, and the new style C/K got the single belt. Possibly different with a 454, but the motor I have now is an 86, that had the dual belt, and the 89 crew that I used to have. But I've had an 89 K3500 with a 454, that had the single setup on it. Just another way of GM confusing the public..
As for what motor, get the most band for your buck. Dunno how it is where you are, but a local late model junkyard is tripping over LS engines. They have 4-5 tiers of these motors sitting on the shelves.
Good read on swapping an LS....http://lsx4u.com/home.html
As for what motor, get the most band for your buck. Dunno how it is where you are, but a local late model junkyard is tripping over LS engines. They have 4-5 tiers of these motors sitting on the shelves.
Good read on swapping an LS....http://lsx4u.com/home.html
Once again, thanks for all the help.
No offense to the people that mentioned their satisfaction with the stock performance of the ls's, I realize we all have different performance expectations/wants, but there is no way that any near stock LS could compare to the ram jet (even if it's fuel injection system is archaic (not saying your wrong, I am so ignorant that I cannot honestly speak intelligently about that).
That being said, I know the LS's are capable of pretty much anything, and I am trying to determine now I one can't be built with +450 ft/lbs @ 1800-2000 rpms, and if so can it be done for the cost of the ram jet. Still thinking turnkey bc of my time constraints (baby and I still have to be the trim carpenter for my new house), hope to have a decision soon. I want to have an engine ordered by next Friday.
I like the comment about multiple tunes, any ever dick with the LS's with the VVT setup, one builder says they have started making some pretty badass truck and fan boat motors with them.
No offense to the people that mentioned their satisfaction with the stock performance of the ls's, I realize we all have different performance expectations/wants, but there is no way that any near stock LS could compare to the ram jet (even if it's fuel injection system is archaic (not saying your wrong, I am so ignorant that I cannot honestly speak intelligently about that).
That being said, I know the LS's are capable of pretty much anything, and I am trying to determine now I one can't be built with +450 ft/lbs @ 1800-2000 rpms, and if so can it be done for the cost of the ram jet. Still thinking turnkey bc of my time constraints (baby and I still have to be the trim carpenter for my new house), hope to have a decision soon. I want to have an engine ordered by next Friday.
I like the comment about multiple tunes, any ever dick with the LS's with the VVT setup, one builder says they have started making some pretty badass truck and fan boat motors with them.
LSX For You
Your right, these guys look like that have it figured out. I will give them a call today.
I have not heard from many Ram Jet owners. Are all the K5 problems solved, so they abandoned the forum? Or are they just nervous to speak up bc they wish they have had an LS?
Your right, these guys look like that have it figured out. I will give them a call today.
I have not heard from many Ram Jet owners. Are all the K5 problems solved, so they abandoned the forum? Or are they just nervous to speak up bc they wish they have had an LS?
RJ FI Setup
tRustyK5, what is archaic about the Ram-Jet's FI setup? Like I said above, I am not arguing, just trying to learn. The guys at (http://www.mefiburn.com) make it sounds like the MEFI 4A ECM that comes with the newer Ram Jet's can be tuned just like any other MEFI setup.
There is an article in HotRod where they put one of the first RJ's in project X, it came with a horrible stock tune (as I have heard is common with the old MEFI 3 ECM's), and they had it cranking out an extra 121 ft/lbs & 74 hp at the rear wheels by "leaning out the fuel mixture, and moving to a slightly more aggressive timing curve". There are a ton of variables in going from rear-wheel to fly-wheel, but you gotta think they at least tune up 150 ft/lbs and 100 hp at the fly-wheel.
http://www.superchevy.com/technical...sucp_0710_chevy_mefi_engine_tuning/index.html
Thanks
Chris
tRustyK5, what is archaic about the Ram-Jet's FI setup? Like I said above, I am not arguing, just trying to learn. The guys at (http://www.mefiburn.com) make it sounds like the MEFI 4A ECM that comes with the newer Ram Jet's can be tuned just like any other MEFI setup.
There is an article in HotRod where they put one of the first RJ's in project X, it came with a horrible stock tune (as I have heard is common with the old MEFI 3 ECM's), and they had it cranking out an extra 121 ft/lbs & 74 hp at the rear wheels by "leaning out the fuel mixture, and moving to a slightly more aggressive timing curve". There are a ton of variables in going from rear-wheel to fly-wheel, but you gotta think they at least tune up 150 ft/lbs and 100 hp at the fly-wheel.
http://www.superchevy.com/technical...sucp_0710_chevy_mefi_engine_tuning/index.html
Thanks
Chris
I haven't been to the site I listed in a long time. But if I read that right, 550 horse motor for $3500, then still have it EFI-capable. Not too shabby. I have bout $3000 total into my 454, 400-ish horse, and almost 500 torque, still more than a stock LS engine. Big blocks rule!!!!
No offense taken, my mostly stock 00 GMC Z71 with a 5.3 puts down 253hp/281tq on a chassis dyno with cold air intake and the convertors cut off on the factory tune.
Ive rode in some pretty wicked cam only ls camaro's, there is a camaro running around town with a stock ls2 with stock L92 heads and a custom cam that has a turbo installed and they had it up to 17 psi on the dyno which made 981hp/781tq.
Ive rode in some pretty wicked cam only ls camaro's, there is a camaro running around town with a stock ls2 with stock L92 heads and a custom cam that has a turbo installed and they had it up to 17 psi on the dyno which made 981hp/781tq.
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There is no "e" in Camaro.....
Martin
Martin
Fixed it, thought it looked funny but was in a hurry ( stupid iPhone ).
Over on the 5th Gen Camaro site there are guys with the LS3 that have a cam, supercharger, tune, headers, and exhaust making 550-600hp. All very streetable and reliable with pump gas.
Here is the dyno video of 981hp camaro...
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