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Purchasing LM7 Long Block.... Thoughts, feedback, insight on the next move?
Hello! I have lurked here for a long while so I figured it's time I sign up! So here's where I am at. I'm purchasing the LM7 LB from Jegs. Putting the rest of the engine together has been a bit of a task. Never done this before, been researching and doing my best to make the right moves. I would love to hear any of your thoughts on what I have so far. Didnt wanna deal with newer 5.3s and the VVT and other BS. The LM7 after researching seemed and sounded like the best option.
The biggest questions i have are WHAT AM I MISSING? and WHAT CAM TO USE?
--------------------------------------------------------------------------------------------------------------------------------------------------------------------- 1. Engine - $3,569
GM LS 5.3L LM7 460 HP JEGS Performance 5.3L engine, 1999-2007 LM7 truck applications or LS swap vehicles
2) $2,307 FiTech 75213 LS Master Kit W/ 70013, Plus Force Fuel Delivery # 52175213 (after emailing FiTech, they cleared up the question of whether i had to buy a 99-07 ECM. With this kit, I DO NOT as there is one included) https://www.speedwaymotors.com/FiTec...ry,433533.html 2a) ALTERNATE OPTION $1,956 FiTech 71001 Ultimate LS EFI 500HP Fuel Injection SystemS #52171001 https://www.speedwaymotors.com/FiTec...ms,328451.html 4) $579 Speedway 1999-2003 Vortec V8 Wiring Harness #91009903 https://www.speedwaymotors.com/Speed...ess,46373.html 5) $913 1973-87 C-10 LS Swap Radiator with Oil Pan/Headers Conversion Kit # 9100265 https://www.speedwaymotors.com/1973-...it,468658.html
Complete your next LS Swap into that 1973-87 C10 Squarebody Pickup Truck with these installation conversion kits featuring headers, motor mounts, oil pan, and radiator with hose adapter. 5A) ALTERNATE OPTION $724 LS Swap 31 Inch Double Pass Radiator w/Dual Electric Fans/Oil Pan https://www.speedwaymotors.com/LS-Sw...an,468527.html 6) $787 #72042051 Trans-Dapt 42051 Engine Swap Kit, 1973-91 C10/C15 2WD https://www.speedwaymotors.com/Trans...ed,282355.html
Swaps GM LS Engine into 1973-91 2WD Chevy/GMC C10/C15 Trucks and SUVs 1-3/4" tube diameter 5 quart capacity 3" exhaust diameter Automatic/Manual transmission Uncoated finish Kit does not include an o-ring for the oil pump pickup tube Oil pan does not have an option for an oil filter, therefore, oil filter relocation kit # 289-81019 is suggested 7) $403.95 DiabloSport Predator 2 Platinum Programmers 7220 8) $75.60 LS1/LS2/LS6/5.3/6.0 to TH350/700R4/4L60 Adapter Flexplate #57534610 https://www.speedwaymotors.com/LS1-LS2-LS6-5-3-6-0-to-TH350-700R4-4L60-Adapter-Flexplate,60449.html
5.3/6.0 to TH350/700R4/4L60 Adapter Flexplate This flexplate allows the use of GM TH350, 700R4, 200-4R, 4L60, and Powerglide transmissions with Gen III LS engines 9) $479 K&N 77 Series High-Flow Performance Air Intakes 77-3070KP https://www.summitracing.com/parts/k...make/chevrolet
I do wanna upgrade the cam a bit. She wont be towing ANYTHING so no need for a cam geared for that. Something that will wake up that 5.3 even MORE. I am SURE I'm missing something but....
My brain is fried going over prices and links and reading info. Hahaha Thoughts?
Thanks for your time and input in advance! And I am happy to be here(officially)!
PS this is what it all is going into.... That's my 1st baby
In my opinion half of the benifit of going with the LS is using the computer shifted overdrive trans like a 4L80E. I usually use a 4L80E, but I did put a 6.0L in an 87 G20 and left the stock transmission (TH400) but its a box and with the 3.08 gears would not have benifited much from overdrive. If you currently have a TH350 or 700r4, I would pull it and swap to a newer trans.
Personally I converted the 2006 harness that came with the 6.0L to a stand alone. I got the 80K mile 6.0L with the harness, PCM, pedal, etc for $450.
Those swap kits are $$$$ for what they are. All you need is a F-body pan & pickup, a set of C10 LS swap mounts and a set of speed engineering C10 headers or Ebay/Amazon LS swap manifolds. Literally half the cost.
Also if you want a decent harness, use a BP Engineering harness.
My buddy uses the stock air box and intake from a LS truck on these, by bolting them to the battery tray. He uses the stock LS battery cables by installing a new replacement driverside battery tray for a diesel.
Finally he uses the same stock radiator with a set of NV200/City Express electric fans.
No way I'd run a Fi Tech unit on my truck. If you want trouble free standalone systems for LS engines, go with a Holley Terminator system.
It's a harness, computer, wideband oxygen sensor all in one purchase. Then just buy the correct size fuel injectors for your horsepower needs and have a large enough fuel pump.
The $500 intake system is a waste of money man, it's a freaking tube with a filter. You could build one for 1/5th the cost.
It has an upgraded cam in it already that's larger than what's in an OEM application for a real LM7.
222/231 .545/.545 112LSA
Also the upgrades they have already done give it better compression and higher flowing heads. It's basically an Iron Block L33 with stage 4 Low lift cam.
FWIW TSP Stage4 low lift is 222/226 .550/.550 111+3 LSA
If you're wiling to buy a $500 K&N, and $2300 on engine management, but the engine is near minimum. So far your package is over $12K, and you need exhaust, accessories, plus some other stuff. If you have a trans planned, you're already near $20K. I just don't see why you wouldn't bump up what you have so far to $13 or $14 and get a 6.0 longblock, then add your own heads and cam package. For another 150 hp and ft lbs, plus a lot more low torque. Or even buy this in a long block, and get your own heads/cam package. This isn't bad necessarily, but it's just using stock leftovers, mixed and matched for easy results. The numbers look okay, but just saying, you can do this with what you could probably find in your junkyard, refurb the parts, and have an engine builder do it. It's just so ..... bland. There is just no spice in your engine, it doesn't even have salt.
If you're wiling to buy a $500 K&N, and $2300 on engine management, but the engine is near minimum. So far your package is over $12K, and you need exhaust, accessories, plus some other stuff. If you have a trans planned, you're already near $20K. I just don't see why you wouldn't bump up what you have so far to $13 or $14 and get a 6.0 longblock, then add your own heads and cam package. For another 150 hp and ft lbs, plus a lot more low torque. Or even buy this in a long block, and get your own heads/cam package. This isn't bad necessarily, but it's just using stock leftovers, mixed and matched for easy results. The numbers look okay, but just saying, you can do this with what you could probably find in your junkyard, refurb the parts, and have an engine builder do it. It's just so ..... bland. There is just no spice in your engine, it doesn't even have salt.
The heads don't raise the compression in this case. The flat top pistons do.
In this case the heads actually lower the compression to a more manageable 10.0:1 ratio
The heads don't raise the compression in this case. The flat top pistons do.
In this case the heads actually lower the compression to a more manageable 10.0:1 ratio
So its the heads and the 4.8 pistons? This just seems like the budget engine, someone would have built from spare factory parts 15-20 years ago.
If it were me. I would grab a 6.0L or a 6.2L because we all know there is no replacement for displacement.
Chevrolet Performance 19432690 Chevrolet Performance 6.0L 364 c.i.d. 452 hp long block crate engine
Chevrolet Performance 19432422 Chevrolet Performance LS3 430 hp long block crate engine
Chevrolet Performance 19432424 Chevrolet Performance LS3 495 hp long block crate engine
No One ever said, gee I really wish I got the smaller engine...
But more often than not they Say If I had to do it all over again, I wish I would have spent the extra money and started with the larger
So its the heads and the 4.8 pistons? This just seems like the budget engine, someone would have built from spare factory parts 15-20 years ago.
GM produced them with an aluminum block and called it the High Output 5.3L under the RPO L33 from 2005-2007 Classic.
You can get the same rods, pistons and heads from an LS4 too and stick them in an Iron block. Did this 2x with a friends during the pandemic. One put a TSP stage 2 Low lift cam in it. the other used some 862's and a left over LS2 cam he had laying around,
Please stay away from FI Tech. Go with the Holley Terminator X. Ill even tune it for you for free to keep you away from the FI Tech Junk.
Ive swapped over 3 cars and 7 trucks from FI Tech to Holley this year. Got a big box full of junk that they were no help on.
Why mention the standalone ECU stuff and also the Diablo SPort programmer for stock PCM?
Also for $3600 that kinda hurts for a stock 5.3 with just a cam.
Just finshed a 408 for a customer. 6.0 was $600 from a buddy. Sold rotating assembly for $200.
K1 Crank, K1 Rods, DSS Pistons, King XPN Bearings, M10295 Oil Pump, Cam Motion Cam, Cam Motion Pushrods ,243 Heads with .670" Springs/Ti retainers, Johnson 2110R LIfters and Machine work with balancing it come out to $4100.
I know you said you didnt want to go thru building something but it sure saves some money and that was a extreme example.
Finished a 5.3 for my wifes tahoe last week and have less than $1100 in it with bearings, rings, oil pump, Lifters, cam motion cam and springs.
I see several ways to save you quite a bit of money.
09-09-2022, 02:22 PM
Purchasing LM7 Long Block.... Thoughts, feedback, insight on the next move?
