2015 Rocket rear %?

[jrkracing54]

I have a 2015 Rocket that we bought last year and only ran a couple times at the end of the year. It was always loose. I scaled the car and the rear % came out at less than 52% but I was told by Rocket to run it there. I'm thinking that is too low but was just wondering what some of you other guys were at. I'm gonna rescale and add weight but not sure how far I need to go. This is a limited late about 525 horse steel block wet sump engine. I run in Florida mostly East Bay and Volusia but once in a while at BRP. I'm already over my 2300 Lb. minimum weight but I can't drive it as loose as it was. Any info is greatly appreciated. John 1*

[25rjr]

These Fla tracks made it tough to get rear% with a steel block motor, esp if you're a bigger driver. Are you running the Spec Brodix alum heads? If not, you'll just have to keep adding lead (not passed the rearend though) until it gets tight enough. Ive always had to run at least 54-55% rear at those tracks.

[Kwoods25]

Put a 1 in spacer on LR and try that, how much gas are you running in rear and what size tank? Also what springs across rear

[jrkracing54]

I have the Fuel safe wedge cell 28 gallon and I scale with 18 gallons in it. I have a 225 in the right rear and a 175 in the left rear. I may try the left rear wheel spacer. I own 2 brand new ones from Wehr's that have never been on a car. John 1*

[Kwoods25]

Putting one on the LR will tighten her up pretty good

[25rjr]

I have the Fuel safe wedge cell 28 gallon and I scale with 18 gallons in it. I have a 225 in the right rear and a 175 in the left rear. I may try the left rear wheel spacer. I own 2 brand new ones from Wehr's that have never been on a car. John 1*

I forgot to tell you in the pm that we always ran the lr wheel spacer. That was the first thing Josh told us to do.

[jrkracing54]

My car does not have the 1" shorter left rear tube and axle. This rear came out of my old car and was set to their old standard. From what I was told they always run the spacer on there and that was only put on there so it could be taken off for some of the bullring tracks they run on the Hell tour like Farmer City and Macon. Just so everyone knows what I'm working with. John 1*

[Dirtmod13]

My car does not have the 1" shorter left rear tube and axle. This rear came out of my old car and was set to their old standard. From what I was told they always run the spacer on there and that was only put on there so it could be taken off for some of the bullring tracks they run on the Hell tour like Farmer City and Macon. Just so everyone knows what I'm working with. John 1*With Which front end do they recommend using the LR spacer, blue or black?And what year chassis is it. I spoke with josh a couple times and he never said anything about it. Maybe he just assumed we had it.

[RacerX10]

My Rocket manual says the 1" spacer is for the orange car, which is apparently the one with the 1" shorter LR axle.

[TheJet-09]

I'm hijacking the thread, but a kid who runs very good in a Rocket by me has the LR spacer on to start the night, then takes it off at feature time. That seems like reverse logic to me. Is that Rocket's recommendation or am I missing something?

[chop6259]

I would double check that you have the 4 bar links in the correct hole locations. We used to have a GRT and switched to a Rocket chassis a few years ago. GRT would references holes from the top while Rocket references holes from the bottom. I can't tell you how many times we accidentally put the bars in the wrong hole because we were used to referencing from the top down. If all other things are measuring out correctly, I would start looking for oversights like this. Especially if you are new to the chassis.

[RacerX10]

I'm hijacking the thread, but a kid who runs very good in a Rocket by me has the LR spacer on to start the night, then takes it off at feature time. That seems like reverse logic to me. Is that Rocket's recommendation or am I missing something?

Agreed, that makes no sense at all .. unless there is something very wonky on that car (non-standard)

[a25rjr]

I would assume, his car is getting too tight. That's common if you have to run 55's or similar on the rear, and build up enough temp to make them grip. They don't start working well until they get to approx. 150 deg.

[mark1971]

Josh drove a crate late model in Florida and he left the shop with 52.5% in the rear. We are getting ready to start this year with a pair of new 2015 blue front ends so I'm interested in how this works out for you. Both cars have the wider rear ends from black front chassis.

[grt74]

I'm hijacking the thread, but a kid who runs very good in a Rocket by me has the LR spacer on to start the night, then takes it off at feature time. That seems like reverse logic to me. Is that Rocket's recommendation or am I missing something?

funny you've said that,think about it this way,if your a very good driver in the slick (car is driven straight)but suffer when you qualify(because you need to throw it and it always over rotates),the spacer will help you and its a very easy adjustment

[TheJet-09]

@grt74, He is very good in the slick. Actually all around. I figure it's an easy way to adjust bite without turning on the coilovers. At least if you feel wheel weight is more important than wheel spacing?