541 Refresh & Dyno Results
 

Sharing some results from our recent 541 Dyno session. This engine has been in our stable for many years and needed a refresh. Most recently it made 955hp. Bill Meyer refreshed it with some help from KRE for cam and rotating assembly. Jax Engines for machining. Engine made 993hp on Q16 and 979hp on Renegade 114 at 7300rpm. Some details: KRE 430cfm Hi Ports, KRE spec'd 50mm cam, Scat crank & Callies rods. Reused Ross pistons. Moroso pan. 14.2:1 compression. Hope to get 300-400 passes from thiscombo in our bracket program. Special thanks to Bill Meyer, Jax Engines & KRE for tech support.

Nice! Great to see a high powered bracket build

Congrats Aaron!!! That sucker is making some steam!
Best of luck to you guys in your up coming races.

nice numbers. what cfm carb? was there any bearing abnormalities ? what do you normally shift rpm wise ?

Great job Aaron.... Thanks for sharing.

NICE!

Thanks Aaron for the info.

:)

Thanks guys. Sharing to help others in hopes we can keep the brand alive. I'll let Bill Meyer answer any of the tech questions. The refresh was required as I started to see a loss of power after over 300 passes over the past 2+ years.

Just throwing out another thumbs up for Bill & Jax. Bill did a little work on mine, and it spins up nicely!

Sent from my SM-G965U using Tapatalk

Hopeful Bill can share what he found when he tore things apart for the rebuild and what caused the power loss

Nice!!

Thanks, guys. The carb is a hp1250. We tried a brand new 1350 and results were virtually the same. Aaron is very perceptive with his maintenance program and pulled the plug on this one at the right time. Main bearing #2 was getting way too hot and had started coming apart. One of the associated rod bearings was getting bad as well. The crank had a small crack on the 2/1 rod journal which wouldn’t file out, so we replaced the crank for safety. This engine always seems to go after the #2 main first, (don’t they all), so I opened the hole up a little on the 113m this time. Maybe 800 passes this time??😀

Did you dobthe oiling mod to the main saddle (groove the saddle and drill feed oil in bearing)?
You don't have say specs but just wonder what were the rough differences between old and new cam?

Very nice!

What intake was used? If I remember correctly you said you were going to test that new KRE intake on the dyno? Did that happen at this session?

Thanks,

Chad

Nice work Bill and Aaron.

A build making this kinda power going rounds is impressive.

Best of luck in 2020!

Calvin Hill
Hill Performance
708-250-7420

Slow bird - I had not changed the main saddle size oil feed. This time I elongated the slot to uncover a little more hole. Since converting to roller cam bearings, I have been happy with the extra oil that gives the mains.
The cam had a little more lift but a tad less duration. The big difference was lobe sep 112 (old) vs 115 (new). I think I installed it about 113.5 w/new chain.
Chad, we used a BOP intake the same that’s been on it for years. It seems to work the best.

Hi Bill,

Attached pic show a comparison between my #2 main bearing at the end of 2018 (less than half a season) and 2019. Putting over-rich tunes aside, the only changes were increasing oil pressure by ~10lb and switching from Rotella 15-40 (changed oil each day after racing) to Valvoline VR1 20-50 conventional motor oil (Oil was not used more than 2 days racing).

Raven: I’m a little confused on the picture. The bearing on the right looks like it has a little skew line hone issue. Maybe it’s the overlay of the other bearing shell. Anyway, is the # 2 main the one that goes first for you guys. Does anyone else see this trend or what can be done to fix it. I would think based on the oiling route that #1 would be more prone to heat, especially with the front load on the crankshaft..........ideas.....

Billy thanks for sharing. I also have seen the #2 main bearing issue. I would just roll another bearing in #2 at the end of the season.I drill out/enlarge the bearing from the oil feed I’m not really sure how well it works but I still do it. I think your onto something with the roller cam bearings giving the mains more oil. I think it was LPI that drilled out the main saddle oil feed hole and the lifter galley’s to make both bigger to increase oil volume. That might be worth a phone call to Mark Luhn.
Also in a extreme case I think Mike and Eric went above and beyond to feed the #2 main extra oil on their fire breathing nitro motor. There is a thread on here about that somewhere about how they got the bottom end to live.

What oil pressure did you run in 2019?