So with my recent 5.9 swap, its no surprise the bug to get more go power has hit. Especially at tax time. So, i started out with a $404 payment to John Mercedes for 1.7 Harland Sharp roller rockers, new valve stem seals and valve covers. When the rest of my taxss come in, I'm changing my blow master to a free flowing muffler from black widow exhaust. Specifically a widow maker. And then, it'll be a tune from flying Ryan. After those, when $$ allows, I'm going to get a 52mm throttle body from hypotek.

all this combined should add around 45-60 hp gove or take, and 50-80' lbs of torque, wheel gain at that. Next tax season in going to get 4.11 gears.

 

Have headers on that yet? You are going to want them. Even shorties will be an improvement, and will help the rest of your mods bring out their best.

 

No. I have them but not on. Went to do it one day but the y pipe didn't match up right. Got plans for full exhaust, but one step at a time.

and no, shorties give no gain, even with those mods. Maybe on a 500hp engine, but even them the gains are not anything to brag on.

 

Shorties build power in the low- to mid-range, whereas long-tubes give you more in the mid- to upper-rpm range. Running smaller diameter tubes (1 5/8ths) will also do wonderful things for low-end torque. And yes, there are dyno charts to prove that.

Also, any gains you have already gotten from the rest of your mods, will be amplified by headers, no matter which way you go. With the 5.9, do 2.5 inch duals, or single 3". Duals would be better... .

Don't suppose there is a chassis dyno nearby you could run it on, is there? Would be interesting to see the numbers you are producing.

 

the only mods I have are no cat, a 5.9 with plenum fix amd no center divider, and that's it. Dyno is about 125 miles away. Cost $100 or so for 3 pulls I think. But National Trails is closer. I plan on going after I get some things done to her.

Real world, I'm expecting 250-260hp at the wheels, and 340' lbs of torque when I get more things done from above.

And yes, I'm going with 2.5 dual exhaust with a jba y pipe, and 2 black widow widow makers with the headers. I had planned to do that out of taxes, but brain fart said all this first would be more fun.

 

Should be fun. Keep us updated, and give us your impressions of the improvement as you go. Yeah, I know, long-term project, but, it ain't the first here.

 

You bet