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Passin' through
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Discussion Starter #1
With a street port job done to my stock heads (example - Big Boyz), how do they compare next to some midrange perfomance heads set up at 1.900" intake and 1.615" exhaust valves (example - GMR's CNC or RevPerf stage II) ?

Specifically, if I couple them with Andrews 37 cams, 9.7 CR and 95", how much more low - mid range torque will the $850 heads get me over the $300 street heads? Bagger, 2 up.

I'm wrestling with the thought of spending an extra $550 for a couple ft lbs torque. However, more than 10 ft lbs might be worth it.

What's a post from me without a bonus question:
What are the OEM measrments of the stock intake and exhaust VALVES on HD's TC 88 heads (2005 Road King)? I couldn't find the specs in the manual...

As ever, grateful for any feedback.
 

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Average Dude
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Flashkev said:
With a street port job done to my stock heads (example - Big Boyz), how do they compare next to some midrange perfomance heads set up at 1.900" intake and 1.615" exhaust valves (example - GMR's CNC or RevPerf stage II) ?

Specifically, if I couple them with Andrews 37 cams, 9.7 CR and 95", how much more low - mid range torque will the $850 heads get me over the $300 street heads? Bagger, 2 up.

I'm wrestling with the thought of spending an extra $550 for a couple ft lbs torque. However, more than 10 ft lbs might be worth it.

What's a post from me without a bonus question:
What are the OEM measrments of the stock intake and exhaust VALVES on HD's TC 88 heads (2005 Road King)? I couldn't find the specs in the manual...

As ever, grateful for any feedback.
IMHO, Beans porting will compete with "midrange performance heads". Those who actually have his heads will, I am sure, agree. If I were in your position, I would give them to Bean and put the $550 saved into a SERT and a good tune (which BigBoyz can also do real well!).
Give Bean a call!
 

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Their porting is a good value. It will be perfect with a high nine compression ratio and TW37 type cams. Just don't think that a cam change or other add-ons later will push the HP right up the ladder past 1.0 hp/cu.in. It just won't happen. In the midrange there is virtually not a lot of difference on these mild builds unless the tune is poor or the pipe is wrong.
Get a good pipe and tune and you will be very happy with the heads.
 

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YankeeBob said:
IMHO, Beans porting will compete with "midrange performance heads". Those who actually have his heads will, I am sure, agree. If I were in your position, I would give them to Bean and put the $550 saved into a SERT and a good tune (which BigBoyz can also do real well!).
Give Bean a call!
@gree: @gree: @gree:
Had their heads on my 01 with the same build, still among the highest #'s ever posted here for that conbination with ANY heads including CNC, welded, etc, etc... The dyno was reaffirmed on several different machines over a 2+ year period....

I'd put Bean's heads up against anyone's! Ignore the price...

Better yet, just send bean and springer $850 aand tell em to fix up our heads with one of those fine street port jobs if it will make you feel better to spend the $$....
 

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It is impossible to get a near perfect port job on heads with the valve guides in place. If they are removed, they need to be replaced. At the least, this is one premium thing that really should be done. the next is comp releases if you are going over 10:1. If you are going to a high lift cam, stronger valve springs are needed. it is important to have the proper tension and travel, to weak causes a flutter, to strong can flatten the cam.
Bigger intake valves are said to have a slower response at low rpm. I do not know if this is a good idea for a torque engine. Big heavy gasoline powered trucks have heads with small intake valves. These same heads with larger valves in them with popup pistons make a lot of HP.

Whatever you decide to do, make sure that the parts work together. Just bolting together "high performance parts" is not going to give you a killer engine. Do your homework or get a professonal to pick it out.
 

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route66paul said:
It is impossible to get a near perfect port job on heads with the valve guides in place. If they are removed, they need to be replaced. At the least, this is one premium thing that really should be done. the next is comp releases if you are going over 10:1. If you are going to a high lift cam, stronger valve springs are needed. it is important to have the proper tension and travel, to weak causes a flutter, to strong can flatten the cam.
Bigger intake valves are said to have a slower response at low rpm. I do not know if this is a good idea for a torque engine. Big heavy gasoline powered trucks have heads with small intake valves. These same heads with larger valves in them with popup pistons make a lot of HP.

Whatever you decide to do, make sure that the parts work together. Just bolting together "high performance parts" is not going to give you a killer engine. Do your homework or get a professonal to pick it out.
I ported my own heads with the guides in place. I even shaped them a little where they are in the air flow path. I did check the seal afterward. I know a prof porter could do a better job than I with them in.I say save the money for something else.The combo you mention with the 37 cam would be great with a bagger and and 2 up.
I ended up with 96hp and 104 tq after a tune. My first romp on the throttle with me and the OL (400lbs combined) was a little spin and then a wheelie.
just my 2 cents
immo
 

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Passin' through
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Discussion Starter #7
Thanks all for the constructive replies. I sorta guessed this would be the popular feedback: use the $550 elsewhere - but I really appreciate the confirmation. I'm not trying to build a dragster or get better numbers than anyone else... just trying to feed my "grin"

{salute(
 

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nw_guy4_fun said:
Their porting is a good value. It will be perfect with a high nine compression ratio and TW37 type cams. Just don't think that a cam change or other add-ons later will push the HP right up the ladder past 1.0 hp/cu.in. It just won't happen. In the midrange there is virtually not a lot of difference on these mild builds unless the tune is poor or the pipe is wrong.
Get a good pipe and tune and you will be very happy with the heads.
I also share your opinion on this, I have done a couple of those very builds with the 37 cams 95 inch and am doing another one as soon as the heads get back, These builds pull strong, have a nice quiet valvetrain, and excellent reliability, all for a ridiculously low price, I know BigBoyz takes a lot of second guessing from people because of the low price, but big dollars doesn't always equate to big quality or performance for that matter. I like to think of BigBoyz port work as a "working mans" port job, not everyone has a bottomless wallet for a 1350.00 dollar cam sets and 900 dollar cylinders to be topped off by a 1200.00 dollar set of heads, and then be run in the 2000 to 3500rpm range 99 percent of the time. If Bean charged 500 bucks it would still be a great value and he would still be busy as hell. But if your reading this Bean, keep the price low, at least for us repeat customers anyway.
 

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Fastest Chkn N the South!
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I'd say that anytime we're comparing expensive parts v/s cheap it's at least a two fold question...1. How much extra power are we really talking here and 2. how much $$$ is a HP worth to you? Personally, I like a HP to cost me no more than $100-$125 depending on the other factors involved (potential negatives such as labor or tuning costs, drivability or reliability problems etc...) So, if an extra $500 gives me 4-5 HP with no additional negative side affects then it's a heckuva deal to me. Or, if that $500 gets me only 1-2 HP it's not. To someone else $250 a HP might be fine.

I went the $850 head route (GMR) because I know I'm getting a well matched package (I'll pay up a little to remove any possibility of doubt) and I'm gambling that there might just be a couple of extra ponies in there somewhere as an added bonus.....or at least there won't be that little voice in the back of mind wondering if I've missed out on a little.

So, go with whatever gives you the warm fuzzies that you dollar has been well spent. I don't think you can go very wrong either way.
 

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Fastest Chkn N the South!
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BTW, I should clarify that when I mention a HP I don't necessarily mean at the HP peak. I'll take an average of 1 HP across the board over a 2 HP gain only at the peak everytime. So, if $500 extra dollars got me an average of even 2 HP across a wide range of RPM then it very well may be worth it, IMO. It could even be that the low and/or mid-range HP is increased and the peak is not changed and that would also be ok.

Most people tend to talk about "low-end TQ" and "high-end HP" as if HP isn't mearly a calculation of TQ and RPM. To simplify I usually refer only to HP regardless of the RPM being referred to.
 
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