Timing with turbos
Thread Starter
TECH Resident
Joined: Aug 2003
Posts: 948
Likes: 0
From: orlando, florida
Timing with turbos Just wanted to get an idea of what other peoples timing setups look like on a turbo car does the timing drop real low when the boost comes on say like down to 14* @3200rpm(peak TQ) and then work back up to 22* @ 6600rpm. or does it stay around 14* until 6600rpm. just want to get a better idea of how the tuning works on turbo cars. Thanks in advance. 
TECH Fanatic
Joined: Nov 2001
Posts: 1,190
Likes: 0
From: Las Cruces, NM
Re: Timing with turbos Kinda depends on the engine, turbo setup (how big the turbo, intercooler etc), gas, IATs. The Incon kit makes max torque at the roughly same point as stock. I dip down slightly before torque peak then ramp back up. I am runing 9 psi boost on 91 octane with a low of 19 deg timing at torque peak with no knock.
Obviously if you get torque peak earlier you are going to have to tweak the settings more heavily.
Gary
Obviously if you get torque peak earlier you are going to have to tweak the settings more heavily.
Gary
Thread Starter
TECH Resident
Joined: Aug 2003
Posts: 948
Likes: 0
From: orlando, florida
Re: Timing with turbos my TQ peak is at 3700rpm So thats where my lowest timing is and it ramps up from there but I suspect my timing is to low so i`m trying to get an idea of what other people are running. My timing at peak TQ is 15* ramping up to 20 at 6500rpm. Is this decent for a turbo setup? My setup is, stock ls1 except forged pistons, arp rod bolts, arp head studs and 9.1:1 comp. turbo tech 60-1 turbo, tuned on 93 octain. My IAT stays right around 110* under hard driving. Coolant temps never go above 190*F. thanks for the help I really appreciate it. 
TECH Fanatic
Joined: Nov 2001
Posts: 1,190
Likes: 0
From: Las Cruces, NM
Re: Timing with turbos You have never really said what air fuel ratio is, that will have a huge affect on timing.
The only way to tell if your timing is to low is slowly start raising it up, looking at knock, iat, air flow,etc. Once you get some knock back off the timing.
Gary
The only way to tell if your timing is to low is slowly start raising it up, looking at knock, iat, air flow,etc. Once you get some knock back off the timing.
Gary
Re: Timing with turbos set your boost level and stop fooling with it for a while, set your afr the way you want it, then do the above for the whole rpm band.. add and subtract timing till you get negligable knock all the way up.. making slight afr adjustmets to keep that on spot simultaneously..
there really isnt one optimal timing curve for tubo ls1's but i would definitely say baring something unusual going on you should be able to run at least 10psi with 20* timing at tq peak.
i had about 2* knock at 3700 (total after knock was 19*) on the same compression and 93 octane (720rwtq)
there really isnt one optimal timing curve for tubo ls1's but i would definitely say baring something unusual going on you should be able to run at least 10psi with 20* timing at tq peak.
i had about 2* knock at 3700 (total after knock was 19*) on the same compression and 93 octane (720rwtq)
Thread Starter
TECH Resident
Joined: Aug 2003
Posts: 948
Likes: 0
From: orlando, florida
Re: Timing with turbos But its so much fun playing with the boost.
I`ve got the AFR set at 11.5 now and the boost is back up at 10psi now the cars running decent but it feels like its holding back, kinda surges. almost like its not getting enough advance And mightymouse, you now how f**ked up my tune was so I`m gonna start all over with my timing tables and see if I can`t get more out of it. I`m going to start out at 20*deg in the lower right quarter of the timing table and pull timing where I get KR. hopfully this will work. By the way I put my car on a mustang dyno to get my AFR set at 11.5 and it turned out my last tune that was suppose to be 12.5AFR was realy 13.5 so I think thats why it ran like crap after the first tune. my hp was also up from 385 to 411rwhp but thats because i`m holding 10psi all the way to redline now.
I`ve got the AFR set at 11.5 now and the boost is back up at 10psi now the cars running decent but it feels like its holding back, kinda surges. almost like its not getting enough advance And mightymouse, you now how f**ked up my tune was so I`m gonna start all over with my timing tables and see if I can`t get more out of it. I`m going to start out at 20*deg in the lower right quarter of the timing table and pull timing where I get KR. hopfully this will work. By the way I put my car on a mustang dyno to get my AFR set at 11.5 and it turned out my last tune that was suppose to be 12.5AFR was realy 13.5 so I think thats why it ran like crap after the first tune. my hp was also up from 385 to 411rwhp but thats because i`m holding 10psi all the way to redline now.
Trending Topics
TECH Resident
Joined: Jan 2002
Posts: 956
Likes: 0
From: Phoenix, AZ
Re: Timing with turbos From what I've read, yes, you need to worry about consistent KR. I've even heard that if you hit like 3, and then it drops off, not too much to worry about . . . although I personally like to see a big fat 0.
- Dug
- Dug
LS1 Tech Stories
The Best V8 Stories One Small Block at Time
6 Common C5 Corvette Failures and What's Involved In Repairing Them
Pouria Savadkouei
Retro Modern Bandit Pontiac Trans AM Comes With Burt Reynolds' Autograph
Verdad Gallardo
Top 10 Greatest Cadillac V Series Performance Models Ever, Ranked
Pouria Savadkouei
Top 10 Most Powerful Chevy Trucks Ever Made!
Hennessey's New Supercharged Silverado ZR2 Has 700 HP
Verdad Gallardo
Coachbuilt N2A Anteros Is an LS2-Powered C6 Corvette In Italian Clothes
Verdad Gallardo
Awesome K5 Blazer Restomod Comes With C7 Corvette Power
Verdad Gallardo
10 Camaros You Should Never Buy
10 LS Engine Myths That Refuse to Die
Verdad Gallardo
Re: Timing with turbos There are sooo many variables It will be difficult to say. Need to know more about the motor, cam, heads, etc. I do see your sig but is there more there or are you running stk cam. As the cam will determine the amount of cyl head pressure and timing the combo will take.
Jeremy Formato
Jeremy Formato
Thread Starter
TECH Resident
Joined: Aug 2003
Posts: 948
Likes: 0
From: orlando, florida
Re: Timing with turbos mine is bone stock except the pistons(9.1:1) and rod bolts. Stock cam, heads and even intake but i`ll be doing a cam and intake before the new year.
Thread Starter
TECH Resident
Joined: Aug 2003
Posts: 948
Likes: 0
From: orlando, florida
Re: Timing with turbos Well now i`m pissed! The shop that was first to work on my car, the one that installed the turbo and long block has been blowing smoke up my ***. When I toasted my motor they pulled the motor and sent it to another shop to have it done, this i was ok with because I was already pissed at them for messing up my tune. well all this time they have told me that they had the other shop put 9.1:1 comp. pistons in. well I went to the shop that actually did the rebuild and asked for a invoice so I could see what part number the piston where well come to find out the pistons were forged flat tops with valve reliefs 9.9:1comp. 
. It`s not the shop that did the motors falt because i never asked them what they put in. I just didn`t think the shop that I was dealing with had any reason to BS me. 
. It`s not the shop that did the motors falt because i never asked them what they put in. I just didn`t think the shop that I was dealing with had any reason to BS me. TECH Resident
Joined: Jan 2002
Posts: 956
Likes: 0
From: Phoenix, AZ
Re: Timing with turbos That sucks!! Can you prove with the 1st shop's invoice that 9.1:1 pistons were what you were expecting? If so I'd be taking it over there and telling them to make it right!
- Dug
- Dug
Thread Starter
TECH Resident
Joined: Aug 2003
Posts: 948
Likes: 0
From: orlando, florida
Re: Timing with turbos Ya i`m gonna try and get them to make it right but I don`t see them helping any. When i called them and confronted them today with the invoice They did alot of finger pointing and basicly gave me the, So what do you want me to do about it attitude. any ideas on how to get my comp. down without having to change pistons again? Will the LQ9 heads and cometic gaskets get me down around 9.0:1 or do i need to replace the pistons? But look on the bright side it takes a pretty stought motor to take 14psi @ 9.9:1 comp 