Oh well my new bub7 2:1 lost me 3 hp and 7 tq on the same dyno with the same corrections (S.A.E.)! In all fairness I had run shell on the original run (no ethenol) this dyno run had chevron ( recently added 10% ethonol) so that may be a factor but the loss was all the way through the rpm range on a pretty even loss all the way through. The V&H true duals seem to have kicked bub's but on this one dident realy expect alot more but a loss? Damn, so all you 2:1 believers it is not always true! Is a 125.9ft lbs enough,yea it is and I can here my radio now and that was the goal but sometimes you have to give to get I guess.

 

The real question is:

will it still launch the front wheel?

Got any pics of the pipe on your bike?

 

no pic's yet and havent tryed since the pipe install but probably would come up a little!

 

Was there any tuning done on this dyno pull, or was it just a baseline to see what that pipe did with the true dual tune? Just curious. Also, since the loss was all the way through, I wonder how much did have to do with the fuel quality difference on the two runs? I would think the 2-1 would out perform the duals on the low-end at least.

The front wheel would "probably" come up a little????? Funny guy. I'm sure it will still go sky high if you want it to.

Zach

 

I have a pro-tuner so the air fuel was pretty close only a little lean in one spot. The timing was not changed at all for this run, it remained the same for both pipes. The fuel is suspect as well with me but semes like quite a loss for 10% ethonol. However I do know that ethonol hurts power and milage but to that extent?

 

Well you didn't tell us what you where compairing these new figures to so we have nothing to base them on. But I do know that those BUB pipes are only 1 3/4" the entire length.
With such a large engine I would have thought you would need a larger system like a D&D Borzilla to get the full benifit from your build.

 

original pipes (V&H duals) 110hp 134tq new pipes 107hp 126tq bub7 2:1 Called bub there reponse is the bub 7 was perfect for my build and as good or better than the rinehart 1-7/8 headpipe 2:1. Went with the bub7 because they were quieter. They also said the bub7 had a steped headpipes 3-steps and the rinehart was steped 4-steps so if it is 1-3/4 the intire way some one lied.