Nutrition Help

I am still struggling on this 4th disipline of nutrition. I need help. Here is my background of things I have tried. Last year, I trained with a powerade mixture that I mixed. In races I used gels. My HIM last year, I double mixed the powerade in my aero bottle and planned to drink half of it and then fill it up with water and drink the rest, gels to fill out the other calories. Bad idea. By mile 20 I was starting to burp and then around mile 25 I threw up. I could not keep anything down the rest of the bike. Not even water. I would drink it, and then I would burp and it would come right back up. Felt better on the run. Took gels and drank a lot of water. Ended up being pretty dehydrated after the race. This later year, I have been training with gels and water only. Been taking about 2.5 gels an hour and 1-1.5 bottles of water an hour. It has worked really good on my training rides. I did try the Zym tablets you put in your water, but on a training ride I got a really bad stomach ache. Kansas HIM I had water and gels. I had 3 gels before the start of the race with a bottle of water. First 20 of the bike, went through 1 bottle of water and 2 gels. I was taking 1 gel every 25 min. Shortly after mile 20, I felt like I was running out of energy so I took another gel at 20 min. I started burping and then followed that up with my stomach hurting. The "I am on the verge of needing to puke" that is how the whole day my stomach felt. I kept eating a gel every 25 min and drinking 1+ bottle an hour. I felt a little better after I took a gel, but that didn't last real long. On the run I switched over to the gatorade and water only. Drank 1-2 cups of each at each aid station. This got me through, but my stomach never got any better until I stopped running. Then it was fine. I do not think I was dehydrated at all because I peed about 10 times after the race and urine was still pretty clear. I am not sure what is out there that I should try. I like not having a sports drink and just using the gels, but maybe a salt tablet or something. Will that help? My HR on the bike was a little higher than I normally bike at so could that have made a difference. It was at 80% instead of 74% So I slowed the second 20 to get it under 75% thinking that would help, but never felt any better so I just kicked it up again and went. Overall, I never felt low on energy or thirsty. I just wanted to stop eating and drinking. Any suggestions would be greatly appreciated.