eb110americana

iTrader: (4)

My goal is to assemble my own LS3 with new parts. I’m quite mechanically inclined (auto mechanic cert. and experience), but have zero experience in engine building. Things like cam duration, valve overlap, and similar metrics are largely a black art to me, so I need some guidance. For your help and patience, I will share build pics with you along my journey.

I’m looking to take advantage of this board’s collective experience and any site vendors to find a SoCal shop that can guide me to the right parts for my LS3 build, and tune the car when done. I have read the sticky on LS3 > into F-Body, and will continue with any recommended reading.

Goals (in order of importance):
1) SMOG & CARB Legal: I don’t want to have to take my car to “a special guy” to get it registered. California car, so rules are fairly strict here.
2) A/C, Cruise Control, Accessories all functional.
3) MPG: Daily driver, so I’d like to keep things at-or-above the current 16/25 mpg the car gets (I plan on swapping to a 6-speed, so that should boost highway some.)
4) Budget: $10K (I’m also planning a new 6-speed and rear end to cope with the gains. Sell LS1 with automatic to offset some costs.)
5) Quick-to-Rev: Light internals for a free-revving character. It doesn’t have to redline at 9K or make all its power up top, just be constantly ready to play.
6) 450-500 Horsepower: Given my first 3 goals, I am being realistic about output numbers. I don’t want a dyno queen that is grating to drive to work each day. I want something a bit exotic, that delights the senses with lusty sounds and free-revving nature, rather than a big-boy bruiser. Considering a bone stock LS3 makes 430 horses in the Vette, I think this is reasonable.

Absolutely NO:
1) Forced Induction or NOS
2) Relocation of Catalytic Converters or O2 Sensors
3) Pre-Assembled Stuff: I want to build it in my garage.
4) Repetitive Maintenance: I don’t plan to pull the motor again for a long time if I can avoid it.

Ideas:
• Stock bare LS3 block 12623967
• Chevrolet Performance heads, 88958758 or 19201805
• MSD Atomic AirForce Intake
• Matching 102mm Throttle Body
• Lightweight Pistons (valve clearanced?), Connecting Rods, Crank (Eagle?), Flywheel
• 24 tooth reluctor wheel
• Higher Lift Cam
• Higher Rate Valve Springs and better pushrod/Rocker Arm Hardware to Match
• Appropriately Sized Injectors
• Electric Water Pump? (less inertia)
• Catch can or better yet, LS6-style PCV (is this possible on LS3?)
• BBK Shorty Headers, Ceramic Coated (already in use on my LS1)
• Be Cool upgraded all-aluminum radiator
• Aluminum Driveshaft
• Built 6-Speed Manual
• Upgrade old metal fuel tank to 1999+ plastic tank with new pump and requisite hardware
• Upgraded fuel pump? Boost-a-pump?

joecar

The MSD Airforce and the BBK shorties don.'t have CARB EO #...

if you want to goto plain smog station they will notice these.

BTW: FAST 102 and JBA have CARB EO#.

KCS

iTrader: (20)

The Scat I Beam rods are cheap and pretty light. I used them and a 500g Wiseco piston and the bobweight was nearly 80g less than a stock LS3. Mahle sells a piston that's advertised at about 430g and has a smaller 1/1/2mm ring pack.

NAVYBLUE210

2001 Chassis and later Smog
Test plugs into OBD Port
Easier to pass. 2000 and earlier
Is low and moderate speed on
A loaded Dyno very difficult
To get beyond 450 RWHP
with stock LS3 cubes.
What Year is your F-Body?

KW Baraka

iTrader: (7)

I'm going with the Lingenfelter G1-1 cam and 1.8 ratio Comp Cams Ultra Pro-magnum rockers.

With those rockers, the cam specs are 229*/242* with 114* LSA + 1*. Lift at .668"/.668".....valve overlap will be about 6*.

Rockers will require hardened pushrods and guide plates.

You'll also want head gaskets that are about .040" compressed thickness.

I'm also sticking with a stock LS3 intake.

The stock Corvette's 430 HP is at the flywheel.....that's about 360-370 HP to the wheels.

The heads/valvetrain/intake stated above even with a 90mm TB should easily be good for about 430 to 450 HP at the wheels.....or roughly 80HP above a stock LS3.

Of course, after all is said and done, you'll want to get it dyno'ed and street tuned .

KW

eb110americana

iTrader: (4)

Thanks Joe. So far I have been able to squeak by with the BBKs through one SMOG check two years ago. They have all the stock emissions hardware in the stock location, so in theory, they should not affect pollution. The MSD intake is fairly new and still CARB pending, so hopefully it will get approval--but then again, the BBKs have been CARB pending for years, so I'll have to decide if I want to risk it. I also appreciate the notes on the F.A.S.T. intake and JBA headers.

That's exactly what I was looking for KCS! Lightweight parts like that are definitely going to get me to my goal of better engine responsiveness (rather than chasing numbers). The Mahle pistons sound perfect, and I know they are a well respected name, so I will probably go that route. I was reading up on bobweight on the Eagle crank page, and it seems like getting them to balance the crank pre-shipping might be a good way to go, if I know the mass of all the parts I'll be ordering (conn rods, pistons, rings, bearings, pins, etc.) ahead of time. I could potentially order a pre-selected set from them, but then I would not be able to spec special parts such as the Scat rods.

Any recommendations from others? Anyone know of good LS-tuner shop around Los Angeles?

eb110americana

iTrader: (4)

It's a 1998. First year for the LS1.

I should clarify that I am going for 450-500 crank hp, not at the wheels. The final tuning and dyno will be at the wheels, so factor in driveline loss.

I believe it depends on where you live and what kind of SMOG is required, but I thought all cars in my area had to do the dyno test. If I am mistaken, since I am building a new engine, and installing new transmission, driveshaft, diff, and fuel system/tank, would it not be possible to simply use parts/programming from the 2001-2002 cars and spec the later test? Or is it simply the year that matters?

KW Baraka

iTrader: (7)

The MSD intake for the LS3 hasn't been and probably won't be released because MSD testing shows that it ain't much better than the stock LS3 intake.

KW

NAVYBLUE210

If you put a later model engine block in and tell the Smog Shop
You will be referred to a referee station and must have all smog
Equipment for that engine. Then to qualify for the 2001 test you may
Need the 2001 later computer and port to plug into.
That 229*/242* with 6* overlap will not pass a sniffer.

I would consider LS3 Block (standard smog shop would most likely never
Know block difference), with AFR230 heads they have a CARB
EO # and perhaps by extension MMS235s, FAST102 (ported)
Have Tony spec a cam something like 223*/229*-231*, LSA 115*+3*
.610"/.590" should make 450-475 RWHP with all the little details
and drive totally stealth/stock till you mash the throttle.
11.0:1 compression probably as much as you could get away with also
Ideally with as little quench as possible .040 gasket or smaller, that
Cam should have plenty of PTV clearance.
Perhaps even a small 3.90" Stroker Crank with a longer 6.25" Rod.
Best advice would be to talk
With Tony Mamo @ MMS

Tuskyz28

I wouldn't spend a ton of money to achieve what you is after. I have been digging off into my research and development notebook and figure I should share this here information with you. Basically all you need is a cam swap kit.
You can achieve over 490 horse at the crank with the factory cam but if you do a baby cam which would drive like grandma's caddy... 540 plus horse is there.
Read this valuable information here.
http://www.superchevy.com/how-to/engines-drivetrain/1404-three-cam-tests-on-an-ls3-engine-bumpstick-boomerang/

NAVYBLUE210

Sticking with LS3 Heads I would have a little port work done on the
Exhaust side only, biggest cam to pass probably like
216*/224* 117*+2*-3* ADV, would still look at the 3.90" Stroke
If your building from scratch.

KCS

iTrader: (20)

I'd call Volkswagon, see if they can set you up with a special tune to pass emissions lol

joecar

lol...

JimMueller

iTrader: (9)

Intake: I'd either stick with the stock LS3 manifold, or get a modified LS3 manifold from Rick Crawford Racing. $300 plus the cost of the manifold.
Pistons: I'd go with the 4032 alloy. My 4.07" 5cc flat-top SRP pistons are 439g. The lightest Mahle LS3 flat-top piston I can find in their 2015 catalog (http://www.us.mahle.com/media/motors...compressed.pdf) for stock displacement is 458g.
Connecting rods: I went with K1 CH6125ALLBLS8A, 660g 6.125". They make a 616g variant, CH6125ALLBLSL8A, but after speaking with Tom Molnar (former lead engineer at Oliver), he didn't recommend it based upon my projected power level. The Scat I-beams are reputed to handle less power than the K1's... someone suggested to not put more than 500'ish through them, and that made me nervous.
Crankshaft: The OEM unit is quite robust. I'd have a hard time spending almost twice the money on an aftermarket unit for your design goals unless their was a serious performance benefit.
Radiator: When my stocker started leaking bad I read a mixed bag of people receiving aftermarket all-aluminum radiators, be it from BeCool, LGMotorsports, Griffin, etc which had random problems with leaks and they had the hassle of shipping back and forth to resolve the problem. I chose to go with a OEM-style LT1 radiator from the years where the core was a little thicker. It's been working great and I saved a ton of money.
Clutch: If you want quick revving and aren't worried about drag launches, look into a lightweight flywheel. I use a 13lb Fidanza flywheel with the LS7 clutch kit.
Injectors: I'd go with the OEM LS3 injectors since it's easy to find known good calibration data for them.
Fuel tank & pump: If you're going to replace the tank, might as well put in a Racetronix 255LPH kit & hotwire kit while it's out.
Water pump: If it's 100% street and/or open track use, I'd leave it stock. If you'll be drag racing a lot it has value.

gto65lvr

iTrader: (8)

I have a mild cam, TSP headers, LS6 intake and SVO Red injectors and 5.3 2.5 ported heads in my 98 formula and have 405 at the wheels on a slightly stingy dyno from Wongs through an auto and a SS3200 yank.

Not sure why you would want to fight emissions. When you can get what you want out of a stock bottom LS1. But then again on another build I went from ported heads and a cam in a low mile 6.0 to stroking to a 408 with ported ls3 heads for tons more money a tiny bit more HP LOL

Gotta love the sickness

eb110americana

iTrader: (4)

Again, thanks for all the fine words of wisdom. (Also, I apologize in advance for the long post.) Based on this, I need to decide between two potential options: 1) Assemble parts from scratch, or 2) Purchase a complete LS3 crate motor, disassemble and sell extraneous parts, then reassemble with custom bits of my choosing.

If there is any chance that the sum total of all the incidentals, such as sensors, bolts, nuts, brackets, coil packs, etc. may actually cost more (or even the same) to purchase individually than assembled into a $6300 crate motor, this makes more sense for one simple reason: I can be certain not to overlook any individual part on reassembly if I have seen the final product in its assembled form first. As this will be my first engine build, this may be a wise choice for me.

However, as option 1 may be cheaper (and less hassle than selling parts), if I can assemble a build list that is assured to be complete, down to the last screw, I am confident that I can follow a guide to put it together correctly.

The reason I am now considering option 2, is the use of such stock items as the manifold and injectors seem wise:

I did not realize that somehow the MSD intake for the LS3 (#2703) no longer shows up anywhere. I liked the idea of the increased plenum volume, but if it can't be bought and won't pass visual on a SMOG, there is no reason to fight for it. The RCR ported stock intake looks to perform well under the driving scenarios I will be most interested in, so I will gladly take that piece over a F.A.S.T. unit. Any idea how to buy one/get one ported?

Thanks for the link Tuskyz28. I may have read that one before, but it also lead me to this one:
http://www.superchevy.com/how-to/eng...ft-comparison/
Which seems to show some favorable ratings for the Lingenfelter G11 cam. It both mirrors the stock cam well on things like good manifold pressure at idle, and manages to have above-average performance specs through a healthy bump in lift. I would be open to other options, but I suspect they will be similar to the G11. This may be a conservative cam, but if I get too aggressive, it will be easy to fail both SMOG and my mileage targets.

I don't want to get too hung up on HP numbers, as adding 20-70 HP is not a tall order. I am more concerned with how that power is made. It is the difference between the older LS6 CTS-V and the later LS2 CTS-V: both made 400 horses, but the LS6 was much more fun to wind out. More lively with less inertia. More exotic. This is what I am willing to pay more for to build myself.

Very useful link. Using this table for JE Pistons/SRP, the stock displacement 329379 is rated at 438g. Unless there is something lighter out there, this is the best option so far.


I am okay with the lighter conn rods with a 500hp limit, as this is my target.

No matter what I choose, I will still have to have the crank balanced to the lighter reciprocating mass, so there is that. Based on this page, "Eagle Forged 4340 Steel Crankshafts are also available in ‘Lightweight’ versions – Counterweights are knife-edged for reduced weight and less windage. Typical weight reduction is 5-6 lbs." That sounds like a hefty weight reduction for a high RPM rotating piece.


This is good to know. How much power are you putting down now, and under what kind of driving conditions? My car will be in stop-and-go LA traffic in 100+ degree weather, so I want to be sure I won't be sweating just from having to cast repeated glances at the temp gauge. I was quite alarmed to find out how expensive the aftermarket Be Cool units are, even to start. If you are correct, this would save a lot of money. Any others running OEM rads and big power in traffic?


Definitely. I doubt the car will see many hard launches. A lightweight flywheel is for sure in the cards, and the LS7 clutch should match the output specs perfectly.


Also good to know. As long as they flow enough, I'd much prefer to stay stock with the injectors.

Yes, I will need a whole new pump, as the pre-'99 metal tank used a different pump. I replaced my pump about 3 years back, but unfortunately the flap in the filler neck has been letting fuel spill down the side of the car, and a number of parts for the old tank are discontinued anyway. Might as well upgrade to the 0.8 gallon larger plastic tank this time, and get all the right hardware to match. Do you know the exact Racetronix part number I would need?

No drag racing. It will be my daily commuter, but with occasional canyon carving. Maybe the extremely rare stoplight challenge, but I'm more excited by corners. I'm just interested in taking off inertia from the crank, although those e-pumps are surprisingly pricey compared to the belt-driven kind. Any particular reason for this recommendation?

Indeed. Very soon I will need to confer with a shop for guidance before I order a single part. Once I trust their advice, and trust that they can tune my engine to pass SMOG and meet my performance marks, only then will I proceed. So far I have a few leads on shops to look into. Any insight or experience from anyone here?

A & A Corvette Performance
CBM Motorsports
Cunningham Motorsports
MAMO Motorsports (MMS)
RPM Motors

(*Note: I am not endorsing any of the above shops, simply asking for advice on which would be best to build/tune an engine.)

JimMueller

iTrader: (9)

Intake: Rick Crawford is reachable under his username G8-4-Speed here, or Rick Crawford Racing on Facebook. You can also contact Gwatney Performance Innovation (GPI), they are approved by Rick to use his methods to modify the manifold in the same manner.

Cam: G11? I don't see a Lingenfelter G11 cam, do you mean the GT11? Oh wait, I see the GT1-1 now. I think the GT1-1 will give you 5-15HP more above 6300RPM, but you'll be sacrificing 10-25 torque from idle to 5000RPM. Just depends what RPM range is most important to you. For a daily driver, something in the upper-2teens to low 220's on intake duration and upper 220's to low 230's on exhaust duration typically works well on daily driven LS3's, but it also needs to have the right valve events. I suggest contacting one of the well known cam spec'ers here, including but not limited to Kip @ Cammotion, Patrick Guerra, Martin Smallwood (Tick), or Ed Curtis (FTI) in no particular order.

Rods: I'm not sure if that 500HP was at the crank or at the wheels. Found some old correspondence with Tom:

---begin---
Our part number CH6125ALLB-LSSL-8 is a 500 gram rod that is designed to be used in applications where the engine does not exceed 7,600 RPM and uses lightweight (less than 430 gram) pistons and the stroke is 3.622" max. If you are going to be turbo / super charging, spraying NOS or making over 550 HP, I would recommend one of our other rods.
---
I am conservative on my recommendations because I hate it when someone breaks something. I think we could both sleep better at night with the -LSL rod. The light weight ones are usually used in full race engines that see lots of maintenance.
---end---

Crank: Perhaps this is helpful on crank vs bob weight and the usefulness:
http://speedtalk.com/forum/viewtopic.php?t=5063

Radiator: On a Mustang dyno I put down about 410tq and 430hp. I live in central Florida, where it's typically 90-100* all summer (May-October). Most of my driving is local city traffic, and I use a 180* thermostat (specifically changed from a 160*). I also use a mix of distilled water & Water Wetter all year around since I don't need to worry about freezing conditions where I drive the car.

Clutch: I've heard the LS7 clutch assembly is heavy for what it is, but the Fidanza 13lb flywheel helps the RPMs both climb and fall faster. There may be something all around lighter which gives you the desired feel.

Fuel pump: I think this is what you'll want: http://racetronix.biz/customkititems...RFPK%2D001&eq=

Water pump: On the street they just aren't as reliable; they won't give you any warning when they go out. I've read of people having to carry spare fuses so that if the pump blows a fuse they can just replace the fuse. They tend to wear out sooner than a mechanical pump, and it may not work well with an underdrive pulley. I've read that they offer constant flow, meaning it doesn't increase with RPM, which means they won't cool as well when constantly at high RPMs, such as on an open track such as Willow Springs.

Speaking of an open track, if you ever have ANY intention of open-tracking the car (even just as a student), you must know that the LS3 has a serious problem with oil starvation on long left-hand sweepers with sticky tires creating high lateral G's. The oil pools in the passenger head, uncovering the pickup tube in the pan. The best way around that is a dry sump system ($$$), but the trickier part is where to locate the large oil tank that goes with it; some people relocate the battery to the rear and place the tank in the OEM battery location. You might get by with a combination of Accusump, baffled oil pan, higher oil level, not spinning the motor as high, using street tires instead of race tires, etc. YMMV.

eb110americana

iTrader: (4)

You are correct, Jim, on the Lingenfelter cam: there is no G11. I in fact meant the GT11 however, not the GT1-1. The GT11's specs are:

215/231 duration @ .050 lift - .631/.644 lift with 1.7 118.0 CL

This falls fairly well within your recommended range, with perhaps room for a little more intake duration. As is though, it did surprisingly well in the 9 cam comparo I referenced. The GT1-1 is definitely not the right cam for what I am doing.

Thanks for the crankshaft discussion link. I read almost all of it. It pretty much backs up my understanding so far. Reducing bob-weight is the most important for two reasons: 1) it is reciprocating, which has more of an effect than rotational mass and 2) any weight removed is instantly doubled in the corresponding requisite mass removal from the crank counter balance weights. However, rotational weight is not to be ignored. I don't want to resort to drastic measures such as hollowing out the bearing insides or anything that might compromise structural integrity, but shaving weight is still my goal to remove inertia from the engine internals and driveline.

When you say "the LS7 clutch assembly is heavy for what it is" are you still talking mass, or pedal feel? I would like a streetable clutch, but of course it has to hold up to the power number I am targeting. I suspect that with the lightweight flywheel, balancer, and other internal parts, the engine will be easy to stall. But I'm okay with the learning curve until I can drive it as well as stock. Plus it will still be 6.2L, so it's not like there won't be any inertia.

For the water pump, I think I will take the risk on the electric Meziere unit, and if it winds up becoming a liability, I can always switch back to a conventional pulley unit. I wonder if I should swap to a larger alternator? I currently have voltage issues at idle if the HVAC fans are on high combined with defroster, wipers, or blinkers. Many have said that this is because the stock alternator is under spec'ed for these cars, but I believe there is a positive battery terminal cable that is failing internally somewhere, so I will replace the heavy gauge sections once the engine is out. There is also that grounding strap under hood on the driver's side towards the front which always breaks. I have no idea where it goes to, but I'll replace that with something better.

I don't have any plans to track the car, at least for now. The Accusump is a unique solution. I like the fact that it supplies instant oil pressure at startup, which probably adds to engine longevity. But that is yet more complexity I don't really need in my application. I would, however, like to select an oil pan with internal baffles, as well as a crank oil scraper plate (if a plate is possible with an aftermarket crank). With all of my suspension mods, my car can pull some serious G-forces, so I feel that would be prudent. I had to put in heavily bolstered Cipher seats just to keep from sliding all over the car.

gm02ceta

iTrader: (9)

I'm processing the idea of upgrading to an LS3 motor and I'm looking to keep all the emission control equipment so I won't have to deal with re-installing factory parts in order to pass every 2 yrs.

Pending your year vehicle smog testing in California has switched from the visual & sniff the tail pipe to visual & OBD2 port testing only.

It appears that the OBD2 test seems harder to pass because it's checking the proper function of the egr, air, evap, 02 sensors, cats, gas cap, etc. Before the change you could have only 1 of those be non-functioning and still pass so long as the C02 levels out the pipe are low enough to pass.

My previous 2000 SS had longtube headers with no egr but did have cats with 2nd cat delete. Although technically it wouldn't pass the visual it would still pass the test once I lean out the fuel trims and/or run a little mix of alcohol and gasoline in the tank. Some smog stations were lax about the visual inspection simply because if the vehicle didn't blow clean you'd fail anyway.

With the visual & OBD2 port only test if they plug into the port and find more than 1 emissions equipment to be non-functioning the vehicle will not pass no matter the visual inspection. :

What I get from this is that tricking the ECU is next to impossible to pass smog if you turn off any of those emissions functions in your tune.

JimMueller

iTrader: (9)

I'm talking about the mass. If you haven't already perused it, check out this discussion: https://ls1tech.com/forums/manual-tr...l-combo-s.html

There are many proponents of upgrading to a truck alternator. While I keep a truck alternator as a spare, I usually use a locally rebuilt CS130D with an underdrive pulley. I don't have any serious aftermarket electronics to truly need the additional amperage.

Improved Racing makes bolt-in oil baffles for the stock pans, and also offers a couple different oil scrapers. Some minor grinding of the scraper may be needed for aftermarket crank or rods.