What's holding it back

The one that really counts is the ET and MPH on that little slip of paper, and 13.1 @ 106 with 3600 lbs is pretty friggin good. Out of a basic but seems well thought out street combo, only 375 inches is nice.

It sounds like the tuning is pretty good. Of course there is more power to be found; for example a torker will make more power as would a set of 1 3/4 headers. Might detract a touch from the streetability. You are limited by the BW.

One thing that can really make a difference is an electrical fan setup if you still have the mechanical.

But i would not worry a lot about the chassis dyno number, the important one is the timeslip and it's pretty good. Unless you want one with a 12 at the front.

I'm sort of thinking bigger headers too, but I would have thought the 1 5/8" would support a little more HP than I'm making. I remember a dyno comparison you posted between the torker and Air Gap and there didn't seem to be much to gain at the RPM I am making.

 

Car was on the scales a while back so the weight should be pretty accurate.

 

Still running the fixed engine fan, so might pick up a little there.

 

On the Wallace calculator, the MPH indicates around 340HP, so not too far off what the chassis dyno is saying once you allow for drivetrain losses.

 

Cam is installed at 107.

 

At the moment the car is very streetable, idles at 600 RPM and is very smooth do drive, so could probably live with it being a little angrier.  

 

Gears are also a bit of a compromise, just swaped out the factory 2.87's for the 3.54's, it's mostly street driven and any more woul be an issue on the highway I think. Bit of extra gearing via the tyres could work, but I've just put the current tyres on, they work out at 25.7", so not super tall, I'm running the Toyo drag radials so they seem to hook up ok. If I could borrow a set of 14" slicks and front runners it would be interesting to see how much it would pick up.

 

Since the 13.1, I have made some changes to the exhaust:

 

 

 

Haven't had the chance to run it on the strip yet, was going today but they cancelled the meeting so need to find another opportunity to run it.

 

I'm also working on dropping a little bit of weight if I can, can run a smaller battery and less fuel in the tank for a start and getting rid of the spare and jack out the boot might help as well.

 

I'm hoping that is enough to drop it into the 12's, should go close.

 

Something else that I have been toying with is that I have a set of 1.7 rockers and I was thinking to run them on the intake side only, I have read that it could help with the split pattern cam and I'm also pretty close to Edelbrocks 0.580" lift limit on the exhaust so can't really use them there. don't know if this would make a significant gain, maybe something to try after I get a time with the new exhaust.

 

 

 

In the Harley world it's all about the numbers at the rear wheel.

dyno shoot-outs are VERY common in the world

of HD and HD based motors.

It's rare for these people to run their hogs down

a drag strip.

 

Braggin rights is dyno paperwork.