View Full Version : Comments on this combination
sean883 19th November 2004, 00:23 I'm doing a 1200 conversion on my 2000 Sporty this winter, here's the parts i was thinking of using.
Ross forged 9.75:1 pistons
bore my cylinders
stock heads-no work
Andrews N4 cams
Bassini pro street exhaust
Anything i left out cause i'm drawin a blank right now.
Anyways would i be better off with getting head work and leaving out the cams? I can't afford both, and i can't afford Nallins or Head Quarters either.
I have thought about adding the 1200 conversion valves. There is a local guy who is supposed to be awesome with porting and such, i just need to get ahold of him to see what he would charge.
edman 19th November 2004, 02:14 I'm doing a 1200 conversion on my 2000 Sporty this winter, <snip>
stock heads-no work
</snip>
How many miles on that bike? I didn't plan on head work either, but my valves were leaking and mucho carbon buildup said otherwise.
engine 19th November 2004, 02:37 well, define "headwork"...A basic teardown and inspection/cleaning of heads I wouldn't consider work. Different if you were adding bigger valves and porting/polishing...I would definately have the shop inspect the heads and do any necessary "fixing".
I'd probably go with the cams over porting with the stock cams. You'll get a bigger power increase that way. The porting is something to do when during or after the larger cams are in. Getting higher lift and more air in would be key. Porting will do the same, but to a lesser extent , and would be noticed more with the bigger cams... Polishing the exhaust port and combustion chamber is good, too...but it costs $$$. Leave the intake port unpolished, will hepl in fuel atomization/swirl-effect.
sean883 19th November 2004, 04:08 As far as head work i meant porting, polishing, bigger valves. The bike has around 10,500 miles so a good cleaning, inspection was already planned. I just wasn't sure if my money would be better spent on ported, bigger valve heads with stock cams or stock heads and N4 cams like i had planned.
Flamin883 19th November 2004, 05:27 I thought that head work with stock cams would give you moor bang for the buck than cams and stock heads. Also in the long run head work will probably be cheaper. Flat tops now, not dished now and flat tops next year when your ready to upgrade next year, + rings, gaskets, hone to fit & wristpins. 2 teardowns vs. 1. DO NOT DISCOUNT HQ or NALLINS, sometimes moor is less. QUALITY proven work (formulas) the first time from guys who know what they are doing and do it daily. Does the machinist in town do Harley heads & jugs regularly? Do you want him to use your heads & cylinders for practice??? HQ & Nallins probably bore cylinders cheaper than him anyway, somethin like $80 hole. HQ ports polishes and installs valves springs guids etc, brand new heads ready to bolt on for right at $800 I believe, sounds like a lot now, but Whats it gonna cost if you get boat anchors from someone who thought they could do it??? Ask Stryder. How much you gonna spend on 2nd teardown to do it later? Where ya at Narley? I'm not picking on those guys, but remember reading about their experience. Good luck with whatever you decide, but at least call HQ and Nallin get some quotes, ask about a discount, :shhhh mention XL forum or XL list :shhhh :shhhh :shhhh ya never know I do
whiffy 19th November 2004, 10:35 Sean,
Get the heads ported and run flat top pistons, not the dished conversion pistons. I wish I had done it that way. This gives you the option of adding cams at a later stage with performance increase. If you fit N4 or similar with standard 883 heads you will not get the performance increase you expect as the 883 valves are too small to fill the cylinder properly with high performance cams.
The standard 883 heads and cams with 1200 bore work fine for tourque with dished pistons. Great for general touring use.
If you want to make more power then you have to port the heads, fit larger inlet valve (or fit XB heads now) and run flat or domed pistons. You can always fit performance cams later to take advantage of the better breathing the engine has with the head work, when you can afford it. The engine will run fine with the standard cams with the ported 883 (or XB) heads.
As was mentioned before, why re-build the motor twice (as I will have to do if I need more power) when you can do this the once?
Whiffy
sean883 19th November 2004, 15:23 $700-800 for just the heads is not in my budget. I'm going to be in school for the next 3 1/2yrs so even if i'm not happy with the dished conversion it would be quiet awhile before i could afford do anything about it.
The guy that i thought about taking my heads to owns a cycle shop and i've heard nothing but good things about him. But he may be out of my budget too, just need to talk to him and find out his prices.
The machine shop that's doing my cylinders does a lot of work on Harleys. They use torque plates and fit the piston to the cylinder and are charging $50 a hole.
If the cams and stock heads won't work good togeather than i just won't buy the cams and save that much money.
Turbota 19th November 2004, 18:20 Parts need to work in combo. You will not benifit enough from just more aggressive cams if the heads don't breath propery.
On the other hand, a very good flowing set of modified heads will not perform to expectations if the cams (stock) won't allow the heads to flow to there max potential.
The correct combo of parts creates a performance increase that's greater than the total sum of it's individual parts. (synogen)
Ron,
Turbota 19th November 2004, 18:26 BTW, if you plan on useing more aggressive cams which normally have a greater valve overlap, I would consider increasing the compression ratio of the engine ... The greater the valve overlap a cam has, the more compression will be lost due to the greater amount of time the valves are in a patially opened position for each stroke of the engine (to include the compression stroke)
Shu 19th November 2004, 20:00 Sean, check you PM later today. I will send you my dyno sheet from a similar set up and you can decide for yourself. I think I can round up one from a similar setup without cams to compare to as well. Give me a little while and I'll try to get it to you.
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