Dyno Date with new Predator

[Wharf Rat]

Getting a Predator this weekend and I have an hour of dyno time scheduled. So I have a couple questions.

I know I am looking for an AFR of about 11.5 or so at higher RPMs but WHEN? 4000? 5000?

What about AFR below say, 3500?

Timing? I can't find much info about adjusting timing w/ the Predator? Better left alone?

Lastly, in a month or 3, I am going to get around to putting on a MRT catted H-pipe. Is that going to change things enough that I will need to retune? Will it make me leaner or richer?

Thanks, hopefully I keep all the pistons under the hood. I'll post graphs if I am smart enough.

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IF YOU HAVE PULLEY MODS AND EXHAUST YOU MIGHT NEED A CUSTOM TUNE TO BE ON THE SAFE SIDE. iAM RUUNING 12.5 ACROSS THE BOARD A LITTLE LEAN. BUT IAM IN THE PROCESS OF GEETING A NEW TUNE. NO DENOTATIONS. I COULD ADD FUEL BUT THE TUNES OUR FREE. MEAN WHILE JUST ADDING A LITTLE RACING FUEL, TO HELP IT OUT.

 

[hj16]

2500rpms - 13:1
3000rpms - 12.5:1
3500rpms - 12:1
4000rpms - 11.5:1

I usually just go by that, it makes things simple

 

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I Am Hoping To See Similar A/f Numbers On The New Tune. And Keep The Same Hp/tq Numbers.

 

[Wharf Rat]

Well, I had a fun afternoon on the dyno. I don't believe it but here goes.

Bone stock at our dynoday I went 374/370. Since then I added a Magnaflow CB and K&N FIPK and last month I got the new reflash for the stall (AMZ2???).

Run 1: Drove and hour to get there and it was hot and way humid so I wasn't expecting much (shop was AC, though). With no cool down from the drive we did a baseline of 367/385 (SAE on DYNOJET). AFR was mid 11's until it took a nose dive to 10.5. I was pissed and blamed it on the heat from the drive but now I think maybe the new reflash sucks way worse than we thought. Also, I think I let off a little too soon on that run and the RPM #'s on the graph don't jive.

Run 2: Predator Perf tune out of the box- 402/385, AFR mid to low 12's
Run 3: Predator Perf tune 4% more fuel- 417/385, AFR high 11's
Run 4: Predator Perf tune 6% more fuel- 415/385, AFR mid 11's
Run 5: Predator Perf tune 3% more fuel- 454/409, AFR high 11's

The 454 comes at a spike in the line. If I guestimate a straight line I'd say it's really somewhere about 435. I am working on getting the graphs scanned.

I have never heard of numbers that high for a Predator tune and a handful of mods. I was very sceptical standing in the shop looking at the graphs, but on the way home the ass dyno confirmed that there was more power (and I am a firm disbeliever in the ass dyno).

Of course I am stoked but these numbers have to be exagerated somewhere. I think the baseline run sucked and should have been a little higher and the last run peak occured on a spike. Either way from say conservative numbers of 385 w/ stock tune to 430 with a lightly modded Predator tune? Is that possible?

BTW: I went here http://www.idc-solutions.net/ Great guys, nice shop, good prices!

 

[Wharf Rat]

I give up with the wife's scanner
Here's a shitty pic of the last run.

 

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Those Numbers Sound Real Good For The Mods. Hard To Read Chart. I Had Cat Backs And Cai 3.0 Pulley Numbers Jump From 432/440 To 442 /460 With The Stock Pulley Tune Aslo Had To Boast Fuel To Get The Af At 12.