Revolution Performance
Banned
Joined: Jan 2012
Posts: 3,098
Likes: 474
From: Location location.
Back on track I like the idea of a high quality set of big inch barrels and pistons,at 1300 bucks though not so into the idea.
When Jaimie does a similar set for $700 with exchange barrels(I think),there's another 600 left to use on suspension or brakes, I know I could buy these and sell my pistons and jugs for around 200 but that's a bit of effing about.
Jaimie's product would be cheaper for me to play, but the down time for exchange of barrels to the US might be a pain.
If this product was say $1100 and the quality was known to be of a very high standard I'd probably be all over it.
By the way Art gasoline is not the future.
When Jaimie does a similar set for $700 with exchange barrels(I think),there's another 600 left to use on suspension or brakes, I know I could buy these and sell my pistons and jugs for around 200 but that's a bit of effing about.
Jaimie's product would be cheaper for me to play, but the down time for exchange of barrels to the US might be a pain.
If this product was say $1100 and the quality was known to be of a very high standard I'd probably be all over it.
By the way Art gasoline is not the future.
Grand HDF Member
Joined: Nov 2017
Posts: 4,251
Likes: 3,134
From: Texas
If anyone is interested this is what the gasoline future may look like in the US.
https://www.detroitnews.com/story/bu...ards/33902227/
https://www.detroitnews.com/story/bu...ards/33902227/
They're asking Congress to be the bad guy because they want to go to 91 octane gas, and they don't want the customers to be mad at them for requiring premium gas. They don't want to be responsible for their cars requiring gas that costs 40-50 cents more per gallon.
I think it's far more likely that the Trump administration would relax CAFE standards rather than the legislators take responsibility for effectively raising the price of gas for everyone.
Last edited by FatBob2018; Sep 26, 2018 at 11:01 PM.
Seasoned HDF Member
Joined: Jul 2013
Posts: 11,185
Likes: 7,961
From: In my head
(I forget where, maybe Montana or Utah) but about 15 years ago coming home from sturgis on a rainy night we pulled into a 76 gas station for a quick fuel up and saw a pump with 103 octane. Needless to say 3 of us filled up our bikes with the 103 fuel. I remember our bikes running so good and the exhaust fumes was like a night at the lobster house. The next fuel stop was a regular gas station with standard fuel and I noticed the inside of my exhaust pipe was white like a crayon. Not a single bit of carbon left. Maybe it was all perception but our bikes never ran as good as they did that night.
HD EFI Guru
Joined: Jan 2008
Posts: 4,490
Likes: 4,776
Her is what I was talking about with the higher octane from the article.
" Higher octane makes gas more stable under ignition compression — commonly known as knock — which can damage internal engine components. A higher, 91-octane (95 RON) standard would allow engineers to design engines to a higher compression ratio — perhaps to 15:1 over today’s average of 10:1 — and gain more mpg while not sacrificing performance. "
So an engine redesign along with higher octane yields a 3% increase in fuel economy per the article for about a 3% increase in cost. So if you started with a 100 Hp engine, with a redesign on the engine and going from 87 octane to 91 octane you would get 103 Hp............ is it worth it to the consumer, hell no. Is it worth it for the auto maker fighting to make the government standards for fuel efficiency, hell yes.
" Higher octane makes gas more stable under ignition compression — commonly known as knock — which can damage internal engine components. A higher, 91-octane (95 RON) standard would allow engineers to design engines to a higher compression ratio — perhaps to 15:1 over today’s average of 10:1 — and gain more mpg while not sacrificing performance. "
So an engine redesign along with higher octane yields a 3% increase in fuel economy per the article for about a 3% increase in cost. So if you started with a 100 Hp engine, with a redesign on the engine and going from 87 octane to 91 octane you would get 103 Hp............ is it worth it to the consumer, hell no. Is it worth it for the auto maker fighting to make the government standards for fuel efficiency, hell yes.
Road Captain
Joined: Jan 2015
Posts: 626
Likes: 109
From: New York
Reviving and old-ish thread I found pretty interesting. My 2018 Stage 4 108 RGS was built up with RevPerf cylinders to a 124 a few months back. I re-used everything from the Stage 4 with the exception of the jugs/pistons, Rocker-arm Shafts, cam chest innards & pushrods. Went with a Fueling Race oili pump/cam plate kit and a Wood WM8-408 cam. The bike runs amazing and is currently running with a with a T-Max.
I’ve yet to see Dyno numbers, but will have it Dyno’d next month and will share the results if anyone is interested. What I’m feeling by the seat of the pants throughout the gears and what I’ve outrun over these 1400 miles post build, have shown me with certainty that the numbers posted on their site for just the cylinder/piston kit mean NOTHING. When matched with the right components, which is what some alluded to earlier in this thread, this 1200 dollar set comes alive.
I had a lot of reservations when choosing which kit to go with including what seemed to be a low CR of the RevPerf kit vs the FM & S&S, but some pretty reputable local builders had nothing but good things to say about the new RevPerf cyclinder kits. Would I pay for RevPerf’s complete package? Probably not and that’s just because it doesn’t include the exhaust. I’m using a D&D Billet Cat and that’s a 1700.00 pill to swallow by itself with ghost pipe in black. Willing to accept whatever the Dyno tells me at this point. But this Kit significantly outperforms my Stage 4 in every category but gas Mileage. I’m pretty sure I’m taking a small hit there. Lol.
I’ve yet to see Dyno numbers, but will have it Dyno’d next month and will share the results if anyone is interested. What I’m feeling by the seat of the pants throughout the gears and what I’ve outrun over these 1400 miles post build, have shown me with certainty that the numbers posted on their site for just the cylinder/piston kit mean NOTHING. When matched with the right components, which is what some alluded to earlier in this thread, this 1200 dollar set comes alive.
I had a lot of reservations when choosing which kit to go with including what seemed to be a low CR of the RevPerf kit vs the FM & S&S, but some pretty reputable local builders had nothing but good things to say about the new RevPerf cyclinder kits. Would I pay for RevPerf’s complete package? Probably not and that’s just because it doesn’t include the exhaust. I’m using a D&D Billet Cat and that’s a 1700.00 pill to swallow by itself with ghost pipe in black. Willing to accept whatever the Dyno tells me at this point. But this Kit significantly outperforms my Stage 4 in every category but gas Mileage. I’m pretty sure I’m taking a small hit there. Lol.
Advanced
Joined: May 2018
Posts: 52
Likes: 27
From: Berlin, Germany
You will find very different quotes for the compression ratio of the RevPerf Kit on the internet. Even on their Homepage it changed from 10.5:1 to 10.4:1 to 10.7:1 to 11.1:1 over the last couple of month.
I know, alot depends on the used head gasket, but from 10.4:1 to 11.1:1 is quite a difference...
I know, alot depends on the used head gasket, but from 10.4:1 to 11.1:1 is quite a difference...
Road Captain
Joined: Jan 2015
Posts: 626
Likes: 109
From: New York
Good to note! I spoke to RevPerf directly before purchase and was told that the site which reflected 10:7 was actually wrong for some time and that it was actually 10:8. However I was also told that without knowing the actual combustion volume of my SE heads, which seems to be an HD trade secret or something, I cant really be sure What the final combo is without having the heads tested. I know the kit came with .30 cosmetic head gaskets.
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Grand HDF Member
Joined: Nov 2009
Posts: 4,315
Likes: 1,663
From: Tampa
Good to note! I spoke to RevPerf directly before purchase and was told that the site which reflected 10:7 was actually wrong for some time and that it was actually 10:8. However I was also told that without knowing the actual combustion volume of my SE heads, which seems to be an HD trade secret or something, I cant really be sure What the final combo is without having the heads tested. I know the kit came with .30 cosmetic head gaskets.
At those bore and stroke ranges, a 10 thou gasket difference is a change of about .25 on the CR