3.4/3500 Tuning

[koolcamaro]

After all these years I finally have a successful 3.4/3500 hybrid setup. The first time I did this was with the 3.4 Camaro pistons, 11.5 compression, and megasquirt. I never could get that engine to run right as it would cough, stumble, and stop running. It could have been incorrect sized pushrods, too much compression, bad tune, or maybe even an electrical issue, but we will never know.

This time around I did a complete engine rebuild with 3400 pistons. Engine runs well, but I need some help with tuning. Is there anyone that's already been tuning an NA 3.4/3500 that wouldn't mind sharing their spark tables?

I'm using TunerCat to tune my 95 Camaro 3.4(manual transmission). Below is a list of my engine mods:

Fully ported/polished 3500 heads, 3500 LIM, 3400 UIM
TCE 65MM Throttle Body
TCE Adjustabe fuel pressure regulator with stock 22# 3400 fuel injectors
Manley SS intake valves, stock exhaust valves(sigh), LS6 valvesprings, manely retainers/keepers
Mild 260 Comp Cam, lifters, custom pushrods, Cloyes Double roller timing set, and 3500 1.6 roller rocker arms
New GM Main bolts, ARP rod bolts(lined/honed), ARP cam bolts, ARP flywheel bolts, ARP clutch bolts, ARP head studs, and stage 8 locking header bolts
Stock crank, stock rods, and Mahle cast 3400 pistons with Total Seal conventional rings
Clevite main bearings, clevite rod bearing, and durabond teflon coated sbc wide cam bearings
RK sport headers with 3500 header flanges welded in place( thanks John!)
MSD coils, MSD plug wires, and NGK TR6 spark plugs
ASP underdrive pulley system
180 degree thermostat
cheap ebay CAI

[koolcamaro]

3.4/3500 Build Pictures

[koolcamaro]

Hopefully I get this hybrid running strong in the near future. My future plans with this setup is to upgrade the T5 to a T56, upgrade the 3.42 gears for 4.11, and throw on the powerdyne bd11a supercharger with custom brackets and new bearings. I have all of these parts, except the gears, so it's mainly just getting around to installing everything. The supercharger will be a bit more involving as I'll have to worry about rebuilding it first, new injectors, new fuel pump, brackets, and tuning. Since my T5 and 10 bolt rear end were rebuilt a couple years ago I will hold off on the gears and tranny swap. The Powerdyne will be next once i get this NA 3.4/3500 running strong. So if anyone can offer any help on tuning or maybe has some Tunercat files they can send me it would be much appreciated!

[fasteddi]

I run a turbo hybrid so my tables are a bit different but can you cut and copy or upload your timing table here so we can see it?

[koolcamaro]

I run a turbo hybrid so my tables are a bit different but can you cut and copy or upload your timing table here so we can see it?

How much boost do you run and what size injectors? I only ask since I plan to run around 8lbs of boost when i supercharge. If you run about that much boost, then your table might work perfect for me when i go FI. Below is the spark table I'm currently running which is just a 3100 stock timing table.

[fasteddi]

Dang i run alot more timing then you. But its hard to compare. I run 15psi of boost generally. On this table ive attached, it was with 15psi of boost, a decent 270 cam, the hybrid 3100 top end on my 3.1l and 93 octane. No KR but i have very cool IATs considering.

I did run 48lbs injectors previously. I dont want to confuse ya, but now im running E85 on a 3.4/3400 engine that has the RWD pistons so very high compression, I have 80lbs injectors as of now in it. I killed my original hybrid motor about 1 month ago after 3 flawless years of racing every weekend. It did good for a long time. It finally rocketed at 11.23@123MPH on 15psi and 75hp of n20 off the line, right before it finally died...lol

A supercharger tune is alot different then a Turbo tune from my experience with a l67 compared to my turbo car. You timing will be lower as it is but it will still be higher like mine before you go into boost. So in the 80-100kpa areas dont be afraid to run some more timing.

But when it all comes down to it, you have to just dial it in yourself. Adding half a degree of timing at a time until you see KR then rip out what you just added to make it happen and another .5 degrees as well to keep it safe.

Are you running 93 octane right now? That helps alot when adding timing and when you boost the car you will definitely want to run high octane to keep it away from KR exspecially with a supercharger which is grossly inefficient compared to a decent brand properly sized turbo.

[koolcamaro]

That timing table helps, thanks a lot! That's insane that you had an 11 second hybrid that lasted 3 years of consistent weekend racing. It definitely held up like a champ! I hope that I can have similar success with my hybrid setup.

I'll keep that in mind about tuning. I'm just finishing up adding a wideband which i've been putting off for awhile now. Should finish the wiring this weekend and this will help me out a lot because I don't even know if I'm running rich or lean.

I'm running 93 octane. I plan to have it tuned at the local dyno shop here in the next couple of weeks. I figure if I want as much power out of this tune then 93 octane is the least I could do. Do you have any advice on preparation prior to me getting a dyno tune? I'm going to work on tuning the car's fuel tables and when I have it close Ill swing it by the dyno.

[fasteddi]

Yea a wide band helps alot!

Thanks. Yea it was a good engine for sure. At least a solid 250-300 passes on that motor at the racetrack. And a good 50 or 60 of them were 11 second passes last summer though the fall when I finally had that puppy dialed in.

Yea 93 is the best thing to use, helps alot if your trying to add a few ponies from timing.

There isn't too much you can do while you await your dyno tune. You can tinker with the tune if you want, but they know what they are doing and a good dyno tune shop only needs 3 or 4 pulls on the dyno and in most cases. If it was a turbo car with some wild cam in it and so forth its more difficult and could take some more time

Just make sure you get a before and after dyno sheet so you can see what the difference was. Record it on your phone if you can. Also see if you can datalog it or if you can have a copy of the datalog on a CSV file.

Ive never had the opportunity to dyno my car. Im sure it would be a fun experience. So have fun and if they let you hang out with them at all when dyno tuning it, make sure to ask some questions.