Supercharged ls swap drivability.

Jdigitty88

Jdigitty88

Not-quite-so-new-guy
Jul 4, 2016
35
32
18
#1
Background:

I have a 4.8 swapped into my regal upgraded the injectors to fic 775's added a vortech supercharger and switched to SD. For the drivetrain, it has the stock th350 (I know won't last) and 8.5 rear diff with stock gears.

Issue:

This is my first supercharged car. I started tunning with hp tuners I have part throttle ok. When I go to tune WOT I go in third start at 2500rpm but it falls on its face. I don't have the kick down connected if I downshift it's much better.

I think I answered my own question after typing this out but will I get the same affect if tune WOT in second?



Pic for attention:
20180128_152724-jpg.82205
 
zdeckich

zdeckich

Master Mechanic
Jun 23, 2013
463
228
43
Fort Worth, TX
#2
What size is the blower and what pulley with how much boost? and whats the fuel injector duty cycle? pump gas or e85?
 
Turbolq4

Turbolq4

G-Body Guru
Sep 25, 2017
798
715
93
Boise Idaho
#3
Do you have a wideband O2 sensor? My guess is that the mixture is way off at low RPM, wot situations.
 
Turbo Zach

Turbo Zach

Royal Smart Person
Sep 8, 2015
1,051
1,094
113
50130
#4
Do you have a knock gauge and a wide band? I would be scared to be messing around with out them.
 
Jdigitty88

Jdigitty88

Not-quite-so-new-guy
Jul 4, 2016
35
32
18
#5
So for some reason, I didn't save any of logs. As soon as it stops raining I will get a log but from what I can remember I don't think it went over 50% DC.

It's 93 octane pump gas The charger is V-3 SCi Supercharger with 3.60. I'm working my way up so hasn't seen more than 5 PSI I do have a Wideband logging it through Hp tunners and using the stock Knock sensors also logging that. It hasn't seen Knock.
 
motorheadmike

motorheadmike

Comic Book Super Hero
Nov 18, 2009
2,695
2,764
113
Ottawa, Ontario Canada
#6
1. Is your injector data correct?
2. Is this OL Speed Density? I don't see a MAF.
3. Is your MAP sensor scaled properly?
4. Is your IAT scaled properly?
5. Have you confirmed fuel pressure under load? What is your IDC?
6. Did you start with someone else's tune? I hope not.

Tuning a boosted engine is not where a novice should start.
 
64nailhead

64nailhead

G-Body Guru
Dec 1, 2014
756
451
63
Upstate NY
#7
If I were you, then I'd unhook the charged pipe and tune it with the new injectors and SD NA. Once it runs, idles hot and cold and accelerates correctly, then it will be as simple as changing the fuel and timing tables when the charged pipe is hooked back up. That is easy info to steal from someone elses tune - just over fuel it and under time it.

Other than that, I'm with Mike - very demanding to learn HP tuners and work out any bugs when into boost.
 
Jdigitty88

Jdigitty88

Not-quite-so-new-guy
Jul 4, 2016
35
32
18
#8
Update time:
So I took yall's advice and checked everything listed also got Master EFI Tuner Book.

Injector data is from fuel injector clinic, Map and iat are correct. I started from the stock tune.

It drives and I think I have the Ve tables situated definitely drivable AFR"s are correct with CMD AFR's. I haven't touched the timing yet because I have two issues right now.

Exhaust and IAT

The Exhaust is 2 into one all 2in same routing as stock. I'm pretty sure that is choking the engine.
The IAT on a cool 60-degree day, start at 104 and at the end of a 1/8 mile run are at 140. Looks high to me IDK

What do yall think should be next intercooler or exhaust?
 

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