Anyone have any experience with the Redshift 577s in a 103? Any dyno runs? Motor pulls like a freight train with the Crane 290s (Which are a little bigger than the andrews 54s) but has scary cranking compression, and seems to need a little more top end. Build has 10.24:1 static CR, hand ported and relieved S/E heads 1.900 x 1.623 valves with flat top pistons. I want to try the 577s since I already have a set, but am not afraid to go bigger. Also when does a bigger throttle body become necessary? Would a 50mm hurt?

 

What is scarry cranking compresion?......

If its overy 220 lbs, then it could be scarry. If not dont sweat it.

 

Motor is in an 06 dyna, Its a kick in the pants to ride, but it could stand to lose a bit of bottom end tq to gain a few ponies up top. We only made one adjustment to the super rich canned SERT mapsince it only has a few hundred miles on it, and one pull after that. 100tq at 2500, 104 peak and a flat curve, but only 93hp. He said he can get it to over 100 as is, but wants to wait till 1000 miles. I had originally planned to run the 577s, but when I looked at them compared to the stock ones, I found they are ground on a small base circle and I already had the S/E perfect fit pushrods for the combo. Luckily I just scored a set of adjustables from another forum member, and am going to install them with the AMS lifters this week. Just want to know if anyone else has run this cam yet. Also, I think it may want a little bigger throttle body.

 

If you fell ccr is to high few ways to cure.lower compression(I wouldn't unles it with work in combustin chambers) gaskets,mill pistons or unshroud valves some best bet to me.More cam and this depends on riding style.When you checked ccr where both plugs out,battery strong,if engines turns extra quick on check it will read higher,also where lifters fully pumped up this will raise ccr if they are down and your loosing duration(just did this one myself).As said above if its below 220 run it and enjoy just run good fuel and make sure timings right for combo.If factory starting system will turn it fine then I wouldnt worry.

 

I think those cams will hurt you build. but give it at try.

I was thinking of going to the HQ 33 cam, but Doug at HQ told me that in his 120 with 10.75 to 1 comp. engine, the bike seems docile and that his smaller cammed 113 in his bagger feels it has more punch. He will probably put the 575 cams in.

He said if I liked the "big block" power feeling then I should stay where Im at.
and if I wanted the "turbo" feeling get the 33 cams.

I think your compression is too low for that cam aswell.

 

Something I rarely see mentioned is injector size. If you are looking for top end preformance even with stock throddle body bigger injectors help at, "Wide Open Throddle". I bet almost anybody can clean up the Induction Module and get 10% more flow. Just look and see.

 

Thanks Gunny, but since we are already on the rich side, and took some fuel out, I dont think the 25 degree injectors are anywhere near 100% duty cycle. I scored a 50mm throttle body on E-Bay last night, and may give it a try, but it looks to me like the motor just wants bigger cams. I'm not complaining its weak mind you, and we havent leaned on the motor yet to see what its really capible of, I just feel in a dyna, I may benefit from longer duration cams.

We'll see what happens when I get some miles on it, If it doesnt do what I want, I'm threatening to switch to the .030 head gaskets and stuff in some Mackie 598s, that will make it run...

 

I have the Zippers Sleeper 103 build which includes the 575 cam, they also have this kit with the 577 cam and higher compression.

The dyno sheet that came with the kit shows the 577 cam version at 108TQ and 95Hp with stock heads.

My 575 runs very strong, has great lowend torque and low compression, however the cams are noisier than I had expected. I'm still trying to quiet them down.

Dave

 

crane 296 will work great with that compression. my friend is running them and he's getting my by a couple of lengths and i'm making 109/114.5 in my 103 with woods 7h cam.i do get him by a length first and 2nd, but with the higher lift and duration he gets by me. his compression is set @ 10:5 to 1 so he says! lol.

 

Your right.
My last post really had two subjects.

The induction cleanup, even with 50MM is an east to see and do. That helps air flow.

The injector business was a side thing. I thinkall injectors are rated for flow at 80% or so. Probably give some wiggle room. But I do think some guys build a hell of a good build and never think of the injectors.Then talk about wide open HP and TQ graphs. Thats wide open injectors also. Leaving easy HP & TQon the table. Means nothing most of the time though. Till a Stoplight at the right time.
Carb guys think of main jets first thing.
Just some though about don't forget that.

I have heard good about the RS 575.