First off Id like to Tim And TJ for all the help with this project. There was a boat load of work to be done in a few short days. Tim was swamped with other projects as usual but he found time and space to get it done. I will post this up in chonological order as things occurred as it will be easier for me .
The first beast on the list was a customers z400 which had a boatload of money love and time into . A very nice woods racer indeed. I believe he said he had over $15000 into the machine The engine was a 472 cc with just about every power mod that could be done. I forgot to ask for permission to post names or pics so I will just say the results. He ended up with a healthy 46hp which I think is crazy good for a z400.
Next on the list was Karens moto . The engine was the one owns the record for most powerfull stock part motor from many years ago. Since it was built with all worn out used parts and a welded up cable case I decided to test one of my own pistons in it. No big deal if it blew chunks. I set cam timing way back to 104 105 and had a custom right side full titanium exhaust with a early 2000 model suzuki right side muffler on it. It looks great and sound good while being super quiet. Unfortunatly the dyno showed that was a horrible combo as it could only muster 46 horse . We were scratching our heads trying to figure out what the deal was. I switch fuels with no change. I thought maybe when I threw the piston kit in I messed up the cam timing or maybe the piston was just that bad ? So in a last ditch effort to weed out the causes we threw a FMF ti system on and bam it went to 53 horse and some awesome torque. Dyno tuning was stopped as this will never run with that exhaust so it would be a waste of time to see what we could get out of it now that we knew the the problem was an exhaust. I am just glad it wasnt a piston problem. The valves were starting to leak when I pressure tested the engine so I will go threw it ,update the porting ,cam timing and see what the new pistons are capable of .
March 2017 Dyno Week Testing Results
Next up was Tim's 450 quad. His best efforts were 57.5 horse with an open ti pipe. So we threw on my big bore duals with D&D cans and power jumped several horse with no tuning. After tweaking it for a while and more fuel the engine at last broke the 60 horsepower barrier on pump gas no less. This engine really liked the massive tubes and power was as high as 4.5 horse more in the mid range over the FMF system. The look on Tims face when the power chart screen popped up was priceless.
Torque was above 35 forever . What a fricken beast . I will get some more 60hp club decals made for you .
https://www.youtube.com/watch?v=xEbO1DA07Sw
I didnt download Tims dyno charts but did get a screen shot .
Torque was above 35 forever . What a fricken beast . I will get some more 60hp club decals made for you .
https://www.youtube.com/watch?v=xEbO1DA07Sw
I didnt download Tims dyno charts but did get a screen shot .
Now we come to what I was really there for. Next winter, Jamie Nelson wanted a quad to compete in circle track ice racing in the unstudded class. He came across a deal on a pile of Dale parts the owner gave up on and got a good deal. He was thinking of building it into a hybrid Yamaha quad and came to me to see what his options were so we went through the parts to find was was usable. He had most everything he needed to build an engine including a steel sleeve we could bore out to 98mm so thats what we ended up doing.
I spent some time over the winter and did all my updates and porting. The crank was in great shape so Brian at Kinney Racing worked his magic on the bearing update. This was my first engine where the focus was to maximize the valve seat area and run the valve as large as possible without cutting it down. It's also the first engine to use the larger bore velocity stack I designed. One of the requirements was also to be able to run with a quiet exhaust as Wisconsin requires a 96db level limit even for racing on public lands and water ways. There might be a few places we could get away with open exhaust so we tested for both options on the dyno. We plan on having 2 ecu's setup so the exhaust could be swapped out quickly and the preprogrammed ecu installed instead of messing around with the laptop.
But before we get to that another dyno customer showed up with a ported 450r and some time was spent tuning that. I believe it had the hrc exhaust and cams. I sure don't miss the days of carbs. Power was tweaked to 45 horse and 33 pounds of torque.
I spent some time over the winter and did all my updates and porting. The crank was in great shape so Brian at Kinney Racing worked his magic on the bearing update. This was my first engine where the focus was to maximize the valve seat area and run the valve as large as possible without cutting it down. It's also the first engine to use the larger bore velocity stack I designed. One of the requirements was also to be able to run with a quiet exhaust as Wisconsin requires a 96db level limit even for racing on public lands and water ways. There might be a few places we could get away with open exhaust so we tested for both options on the dyno. We plan on having 2 ecu's setup so the exhaust could be swapped out quickly and the preprogrammed ecu installed instead of messing around with the laptop.
But before we get to that another dyno customer showed up with a ported 450r and some time was spent tuning that. I believe it had the hrc exhaust and cams. I sure don't miss the days of carbs. Power was tweaked to 45 horse and 33 pounds of torque.
Here is where the weird happens. First off we install Jamies 460 in the test wrig. Right away its pulling some unreal numbers . I was pretty sure this engine had 55 horses in it which was our goal as that was the norm 10 years ago when I did a bunch of them. With the FMF ti pipe and a D&D muffler it made 58 horse on the first run. Then did a few changes and got it up to 59.61 hp. So OK this our first test and we had not even strapped the duals on yet.
Then Tim suggest that maybe the FMF muffler would be the answer to get this baby over 60 as it has proven track record of giving the best results . So I installed the muffler and to our surprize it lost power . The D&D smoked it handily every run. We ended the night with expectation that the duals would blast this beast way past 60 hp like they did on Tims 450 quad.
So next day we start out with the standard bore stepped duals which have been the standard for years. It was shocking that they could not beat the TI headpipe. Changing the afr up or down did nothing. The best they could do was match the ti pipe in the mid and top end. So we didnt even try going with the quiet mufflers and went on to the BIG bore duals thinking this is going to be the one .
It was kind of a running joke that wouldnt it be funny if we could not get to 60hp no matter what . So again with full faith I bolted on the big bore duals and we let her rip. WTH???? it took forever just to break 59hp and we could only do it once. We tried several types of race gas and they lost about a horse each . This engine loved pump gas and the more restrictive ti pipe and stepped duals. Just the opposite of the norm. And still no 60 horsepower 
SOOOOO after giving up hope we set about installing the quiet mufflers on the Big duals for the restricted noise races. Not to shabby with 57 horse and 35 pounds of torque . That is more 80db quiet power than our 467 stroker motor that won the 2008 championship did with the ear splitting exhaust . Food for thought . I know thats Dale world record but what about all other machines? I think that even beat my 505 for quiet power.
Now that the engine had close to 100 dyno runs on it we racked our brains trying to think of a way to get to 60hp. Since the FMF made the most we reinstalled it . We also removed the inside fine filter of the UNI which is not a problem since its a winter quad. After another battle of tuning at last it happened.