Dynoed again this morning. My last numbers were 560 rwhp and 597 rwtq with a built motor, heads, cams, KB, 100% stock exhaust, and 19 psi of boost. I have had a full exhaust in the past before this engine and was not happy with the noise. But after seeing my dyno numbers and the fact that it felt down on torque, I purchased a Dynatech LT set, twin cats, and Bassani BX cat-back. I also bought the Bassani baffles that go in the tips. My first surprise was that this LT setup was much quieter in the truck than the same basic setup I had earlier. There was one difference, the original setup used the stainless Bassani cat-back and I now am using the coated steel one. I am positive it's quieter, and I'm saying the steel unit transmits less noise to the interior than the stainless one.

To the numbers. With the LT's I couldn't get exactly 19 psi with the pulleys, it either made 18 or 20. So I did a pull at 18 psi with the LT's and made 590 rwhp and 635 rwtq. So a pound less boost made 30 rwhp and 28 rwtq more. This is my street tune with alky, 15 degrees of timing.

Then I pullied it for 21 peak boost. This was on race gas and 20 degrees of timing. It made 621 rwhp and 708 rwtq. I made one pull without the baffles and one pull with. It actually made more hp and torque with the baffles but it was so close it could just be in the dyno itself. The baffles are good for a little more noise reduction in the cab, and cost no power at the 600/700 level, so I will be running them all the time.

Jody

 

Great info Jody, Can you go into more detail on the baffles?

Oh and very good numbers

 

Damn nice numbers. I know that when I put on full exhaust, and colder plugs, I lost 25 horse power because I couldn't get the air in. I had a shoddy port job, and stock upper plenum/throttle body. I am talking to DynoBob about porting my tb, upper plenum and blower.

 

They're kinda pricey at $135/pair. But they do take some of the interior tone out, it is noticeable but not dramatic. They are made by Bassani but would fit any similar diameter tips. By the way, the tape is on there to hold the packing in place; you remove it when you install them in the tips.

 

Thank you for taking the time/effort of doing a before and after results of this mod. Very nice numbers.
Jes

 

What pulley setup did you use to get 21 pounds boost?

 

6# lower and 2.75" upper.

Jody

 

WOW nice #'s

I am seeing 21psi with the 9" lower and 3" upper, but my heads are stock so that seems about right to me.

Bob

 

Thanks Bob!

Jody

 

Wow the price must have changed. From Bassani

All baffles that we have are made to fit Bassani cat backs. They have no part numbers and they are not guaranteed to fit any other application and they cannot be exchanged or returned. They are stainless steel and the cost is $35.00 EACH plus shipping. You will have to tell me the ID of your tip and the length where this is going to fit. Your tip will need a small hole in the bottom to secure the baffle.

See attachments, wrapped in fiberglass cloth, held in place by masking tape. In picture 2, you can see the receptacle for the set screw.

 

I'm going to have to check with my vendor on that one!

Jody

 

I'm glad your getting your numbers that you were looking for.
Do you know greg liggin in Houston? I sold him the KB blower and soon the KB upper intake next week.
CAL

 

Thanks Cal. No, I don't know him.

Jody