T-man TR590 vs. TR625?

[MRO]

I want to run one of these cams in my upcoming build, but still can’t decide on which one.

Here are 2 build ideas I’m contemplating...

Build #1

Bore stock cylinders to 107ci and use JE flat tops

Stock heads ported with 1.9 intakes, stock exhaust & milled to get 80cc chambers.

.030 head gasket

TR590 cam (set at 10.8:1comp)

Stock 46mm T/B bored to 49mm and manifold ported by HPInc.

Stock HD head pipes with cycle shack slip-ons or D&D Fatcat 2 into 1

Build #2

Bore stock cylinders to 107ci and use JE flat tops (set piston/deck height to zero)

Stock heads ported with 1.9 intake stock exhaust & milled to get 83cc chambers.

.030” head gasket

TR625 cam (set at 10.5:1comp)

Stock 46mm T/B bored to 49mm and manifold ported by HPInc.

Stock HD head pipes with cycle shack slip-ons or D&D Fatcat 2 into 1

Now I have seen dyno sheets on both of these cams, but really can’t see any big difference in HP and torque. They both seem to produce similar numbers, thou I would think the tr590 would have a flatter torque band and slightly higher hp with its little more duration and slight bump in compression.

Question is, does anyone have experience with using these cams and if so, how would you compare what the "real world" difference in power band? Any likes or dislikes? My bike is a 08 dyna with stage 1 and a gear change (49 tooth clutch basket), and I’d like to have something that produces more HP and torque in the higher rpm band, and pulls harder at roll-on speeds.

-Matt

[nw_guy4_fun]

Assuming the same "corrected" CR the 625 is the torque under the curve winner, the 590 is a little more high rpm power winner. The 590 especially needs a good pipe as it has considerable overlap and the exhaust port needs to be functioning very well especially the up to .300 numbers.

[laserp]

I'm in a similar situation. I'm leaning to the 625's for my softale 107 I'm putting together, because with my combo and riding style.... love low and mid torque more than 5000 plus RPM nuts. The 625 was designed around a softale/B motor medium weight bike that stays under 6K rpm. I think the 525 would be real sweet, but a little finiky to tune it in at the higher static comp.
As of right now, I'm going with the 107 Axtell kit ( cyl bore, 20 deg. domed pistons, HTCC head recondition), Horsepower inc 55 mm thottle body, TMan TR625G cam with the hyd conversion kit, Baisley Roller Rocker conversion
Tune by Bean this spring

[MRO]

Originally Posted by nw_guy4_fun

Assuming the same "corrected" CR the 625 is the torque under the curve winner, the 590 is a little more high rpm power winner. The 590 especially needs a good pipe as it has considerable overlap and the exhaust port needs to be functioning very well especially the up to .300 numbers.

Thanks Don! Good to know! So would the tr590 require more then a "street port" to take full advantage of that cam? Also, do you think the 49mm TB would be to small? I don’t what to run a TB and set of heads that will not work real well with that cam… If it requires heads with raised and welded exhaust port and 55mmTB, then I would just run the tr625 cam.

-Matt