Dyno tuning questions

[Dean Lampe]

I'm going to the dyno at some point this winter. The bugs are sorted out with the rest of the car and it runs good in its fresh out of the crate tune but I know I'm rich and my knock sensor is jacking with my timing.

What kind of improvement can I expect from the dyno tune? Can I set up the system to run in open or closed loop? Does anyone have some before and after numbers?

 

[Alex]

I think I picked up around 40RWhp (forget the exact number); my timing and a/f was pretty wonky.

If nothing else I would do it for piece of mind - even though your engine is not f/i'd you're still putting it through its paces so I'd want to make certain everything is as spot on to ideal (e.g., 13.7 a/f) as possible.

 

[Dean Lampe]

Sorry but what is f/i'd?

 

[Dave]

force inducted

 

[Alex]

Sorry but what is f/i'd?

forced induction - blower, turbo, etc..

 

[Dean Lampe]

Thanks guys, remember this is my first dance with out my good ole Weber's!

If I wanted to add hp, what is the ususal first LS upgrade? Or better yet, where will I gain the most bang for my buck?

 

[Ken Roberts]

The first engine mod I'd recommend is a cam change. Not an off the shelf cam but one spec'd to your particular use. I used "PAT G" for mine. He has a huge following on the forums. He emailed the cam specs to me and I purchased the custom ground cam from Summit Racing (Comp Cams). Camshaft Help-LS1 Custom Cams-Guerra Motorsports-Patrick G cams

CNC porting the cylinder heads would be my next recommendation. I used Advanced Induction for that. Advanced Induction - 270/275/280cc GM 821 Package

West Coast Cylinder Heads is used by Katech. http://www.proheads.com/pricing.html


While you have the timing chain out a upgrade to the C5R ISIS chain is highly recommended. These were used by Katech in their racing program and apparently they have yet to break one. http://store.katechengines.com/c5-r-timing-chain-p30.aspx

 

[Allan]

I gained 30 hp and 30 torque at the wheels on my LS376 without picking up any knock and keeping the AFR where it should be.
Really felt the difference as it hit 95mph in second gear in a flash then the rev limiter kicked in.

 

[Dean Lampe]

where did yu set your rev limiter?

 

[Allan]

where did yu set your rev limiter?

6800 rpm

There was a large gain in HP in the lower rpm's and continued all the way up the rpm's. Max HP was at 5800 rpm

 

[Dean Lampe]

What were your final numbers at the tires?

 

[Mike]

Dean - I'd make sure to have the gas tank filled with whatever racing octane gas you would normally use also. Since your car is track only, not as much as an issue with us guys that use street gas and whatever octane it supposedly is.

 

[bob d]

Dean one of the big benefits of dyno tuning is to make sure the car is tuned properly so you do not run the motor lean, which will result in damage. It is much easier to find the problem on the dyno than on the track. Other than that you will get the feedback for the output at different RPM's which gives you shift points to look for.
Bob D

 

[mark b.]

gm tech on the shelf now did an ls9 cam upgrade to an ls3 engine and they were happy with the results, over 400 rwhp, that being the only change except for some springs things depending on your engine. i have heard the asa cam is good also, don't know how they compare.

 

[FLATOUT]

Buddy is having his cam only LS3 08 C6 tuned at LMR this coming Monday. I know it's not an SLC but I'll let you know what it makes. My 03 Viper with bolt ons and their tune picked up 46rwhp and 52ftlbs making over 500rwhp. Been to so many shops over the years with different builds that I have learned that some are definitely better than others when it comes to this.

Good Luck.

 

[Mesa]

gm tech on the shelf now did an ls9 cam upgrade to an ls3 engine and they were happy with the results, over 400 rwhp, that being the only change except for some springs things depending on your engine. i have heard the asa cam is good also, don't know how they compare.

Isnt an LS9 a supercharged engine? Seems odd to me that a SC spec cam would perform in a NA engine. But I am no expert and would be interested as to why this would work.

 

[mark b.]

yes it is, and the lobe seperation was something like 122.

 

[FLATOUT]

Non SC spec'ed cams will work fine in forced induction packages they just might not be the absolute best option, but certainly won't hurt performance.

 

[Ben Whittle]

Non SC spec'ed cams will work fine in forced induction packages they just might not be the absolute best option, but certainly won't hurt performance.

Seems like what is being discussed is going the other way LS9 cam --> LS3.

 

[FLATOUT]

Seems like what is being discussed is going the other way LS9 cam --> LS3.

Haha thanks Ben missed that slight detail.