I'm getting ready to do the Nallin 1250 Conversion on my '03 883.
Going with New Stock XB Heads with the Nallin's 1250 Jugs and Matching Pistons!!

Question?? What Cams should I go With?? The H-D .497 or the H-D .551??

I Mainly ride in the 3000-4500 range, but I think after the Conversion I'll be into the Upper range also.. Looking for a good flat TQ line from down low on up!! If Possible?? :D

It's hard to recommend a cam set. The .551 is a pretty high lift. I run SE .536 cams in my '03 (w/Thunderstorm Heads) and the valves just barley clear the rockerbox cover, so, I would consider clearance an issue too.

You may want to PM Luckymic. He has the same kit on his '03 and I believe he needed to modify his rockerbox covers because the valves were hitting them and he is running the same cam set as me the SE .536. Or, give Justin a call and ask him about it.

I was talking with someone (Can't remember who at the moment.) in the forum and that person is running with .551's. Maybe he/she will see this thread and post a reply to give you more insight.

txsporty

I'm not sure how much help I can give you, but I had the .551" installed at my 1200 conversion.
I didn't choose it, the motor guy thought it would be best for torque through the whole RPM range and upper rev's.
I just went with regular 1200 pistons and no head work. I didn't dyno the bike before, but 68 hp and 67 tq were the readings after.
The only other difference I noticed was the top of the motor is a little louder now than before.

http://www.xlforum.net/forums/showthread.php?t=60


I can't tell you which is better, but it starts and idles good, and I like the way it runs.

How high will your compression be? I personnally would go with some Andrews. If you want to ride with power on the bottom the N2's will give it to you but keep the compression to 10 to 1 or less. My 1200R made 80+ HP/79ft lbs with the heads done and N2's. Some folks will say not to, but I like em and that's just my opinion.

jimmyheadgear

I take it you didn't have any Clearance problems with the .551's??


barry1967

Not sure what the Compression will be, I'll call Nallin's tomorrow and see if Justin would know!!

What kind of Head Mods. did you Do??

Here's a link or two for you to read. It's great stuff. Be sure to read them. It may make you think differently about how your harley runs.

JET (http://)

J.E.T. Heads (http://cycledoctor.com/JohnsonArticles/JET.html)


That's what I have done to my heads.

Here's a link or two for you to read. It's great stuff. Be sure to read them. It may make you think differently about how your harley runs.

JET (http://)

J.E.T. Heads (http://cycledoctor.com/JohnsonArticles/JET.html)


That's what I have done to my heads.

Man, this Conversion Stuff is Confusing!!!!! I'm trying to get the most Bang out of my buck and not have to send parts all over the Country!! :frownthre
What does JET charge to do 883 heads??

You may want to PM Luckymic. He has the same kit on his '03 and I believe he needed to modify his rockerbox covers because the valves were hitting them and he is running the same cam set as me the SE .536
I had to mod my rocker box covers due to the increased size of the valve springs and spring retainers in the heads. I believe they said, but dont quote me here, the .536 cams will normally bolt on.

I thought I had .551s, but I think I have .536s. I did have to have the rocker boxes clearanced.

--Sean

I had to mod my rocker box covers due to the increased size of the valve springs and spring retainers in the heads. I believe they said, but dont quote me here, the .536 cams will normally bolt on.
That makes sense, the Stage 3 head work. I remember that at the time you where doing the conversion I was puzzled as to why they were hitting when everthing should have been a fairly straight forward wrenching operation.

Check out his website and browse around at some of the dyno's. His is a little expensive on the 883 heads but they are labor intensive.

Jet website (http://www.johnsonenginetechnology.com/index.html)

Luckymic

What heads did you use in your Conversion??


barry1967

I checked out their Site!!! I noticed that he does the same thing with Combustion Chamber as HD has done with the XB heads!!

jimmyheadgear

I take it you didn't have any Clearance problems with the .551's??
My bike is an 04, I don't know if that makes any difference, but no clearance problems, clarennce.

barry1967

I checked out their Site!!! I noticed that he does the same thing with Combustion Chamber as HD has done with the XB heads!!

Ya lost me there. Combustion chamber work? Which pic?

Ya lost me there. Combustion chamber work? Which pic?


Guess I was looking at another site!! :frownthre Branch does heads and they fill the Combustion Chamber then CNC it out...

Justin at Nallin's said I'll have 10.5:1 on the Compression!!! That's using Stock(for Now) XB Heads and a slightly domed Piston..

What heads did you use in your Conversion??

Stage 2 XB heads

Stage 2 XB heads

Thanks, Hopefully I should be OK with the Stock XB heads!! :D

I have a 1996 883 XL that I plan to convert soon. I have all the parts. I am ready to teardown and to send the cylinders out to be bored by a local machinist.

I purchased a set of SE.536 cams (25649-91) from Harley and was told at the time of purchase to just bolt them in and that no head modifications are required. However, when I read the HD installation instructions and the posts on this site I get a different story.

The instructions say that HD recommends the valves springs be changed to
SE #18223-98. The instructions also say that the valves should be beveled for valve to valve clearance.(.040) on stock 883 heads. I am on a very tight budget and was not planning for any work on the heads.

My thoughts are to sell the SE .536 cams and substitute for the SE “Bolt In” cams .497.

Any thoughts?

OKXLRider why not see if the local dealer will just swap ya?

I have a 1996 883 XL that I plan to convert soon. I have all the parts. I am ready to teardown and to send the cylinders out to be bored by a local machinist.

I purchased a set of SE.536 cams (25649-91) from Harley and was told at the time of purchase to just bolt them in and that no head modifications are required. However, when I read the HD installation instructions and the posts on this site I get a different story.

The instructions say that HD recommends the valves springs be changed to
SE #18223-98. The instructions also say that the valves should be beveled for valve to valve clearance.(.040) on stock 883 heads. I am on a very tight budget and was not planning for any work on the heads.

My thoughts are to sell the SE .536 cams and substitute for the SE “Bolt In” cams .497.

Any thoughts?
You shouldn't be messing with any cams on a stock 883 head. Spend the money on head work first. You're putting the cart before the horse. Them be mighty big cams for just a little stock port. Even the stock .470 lift cam could crank better if you port the stock heads.

Everyone keeps saying the 883 heads are no good for cams. I just dropped off a set of 04 883 heads for my 04 1200R to be reworked, new valves( smaller than a 1200 1.715I and 1.480E)and guides, springs and locks.

The 883 heads are better for street use than the 1200 heads in my opinion. I think the smaller ports and valves will help increase velocity and give MORE low end torque( which is what we all want) than the 1200 heads can offer.

I do not want 95HP at 7000rpm. Give me 85-90ft lbs at 3500-4000rpm and I'll have more fun than your 90+Hp,7000rpm screamer any day. I see everyone going Nallins 1250's or stage 3 heads and I look at their website at the numbers they put out. Don't get me wrong, they do great work but 6500-7000rpm engines are not what us sporty owners should be looking at. I don't think they will last long at that rpm. I want a nice reliable 6K max motor that puts out a ton of torque, after all that's our riding rpm range.

All those Buells making 100Hp are mostly Fuel Injected and running Buell 2 into 1 exhausts, which won't fit our sports. I am not trying to trash anyone's opinions or beliefs, just trying to make some sense of it all.

We have v-twin engines that run in the 2500-6000rpm range. Big ports are great for high rpm v-6's or 8's or in-line fours but I don't think it is good for a 45degree v-twin with a long stroke.

When I get my 883 heads back I hope I am not eating my words but we shall see.

The guy doing my heads got mid 90's rwHP on a Buell with N2's. That's a small cam making big power. Maybe his small port heads work. Here's a link to the dyno run compared to a stock S1.

http://www.johnsonenginetechnology.com/JETIMAGES/dynographs/bjetbuel1200.jpg

90ft lbs at 3500 and 80ft lbs at 6000K. Think of the fun that would be to ride.


Rant OFF

PS. go ahead and start bashing me, I can see it coming.

barry1967

Should be interesting what you come up with!!! :D

BAARRRRYYY..You just said in your first paragraph that your gonna take 883 heads and have them worked...DUH UHH...What the hell do you think I said ! Port and polish and flow the 883 heads-then match up a complimentary cam. A .536 lift S/E cam on a bone stock 883 head is over camming and will result in worse performance. Again...don't put the cart before the horse.

What the hell do you think I said ! Port and polish and flow the 883 heads-then match up a complimentary cam

Yes, but they are not being ported and polished. Simply a valve swap, smaller than current 04 1200 heads, radius valve job and making the ports smaller and probably stick with my 480 lifts N3's or maybe back down to N2's. Why does the SE catalog recommended the 04 1200 kit with cams, carb and all only make about 78HP at 7000rpm? Too big maybe?

I was not slamming your post. I just think that everyone is going bigger when we should be thinking smaller. That's all I meant. That is just my opinion.

If I am wrong when my bike is done I will admit it.

I was very happy with my JET heads when I got them back. I went to a 1.715 intake and left the exhaust stock, full radius valve job, and shaved .050 off the base. I dont know what the numbers are but the thing pulls forever and likes it. I have talked to people in my area and they all talk about his heads. His numbers dont lie..hope this helps

Thanks HHahn. Have you been to his shop? If you spend any time talking with him all this stuff makes sense. I can't wait to get my stuff together. But of course the weather here in RI is the same crap you got in CT so it's really no rush. I can't ride until March or so anyway.

I have. Very easy to find from 95. Full of machines and super nice people. very happy with the service and recommendations made at the time I had mine done. I will be returning soon I hope to see what can be done with my Ironheads' heads. Where in RI are you located?

Warwick. Right near the RI and Warick Mall.

Barry1967,

You are absolutely right about the 883 heads and velocity, etc. The largest cam I would run on a stock set of 883 heads is the SE .497" lift bolt in cam or the Andrews N4. As far as bolt in on the SE .531" lift cams, you could, but the stock valve springs can not take that much lift. That is why they try to sell the SE .536 cam as a kit with springs and keepers etc. If you are keeping stock springs with the new valves in the 883 heads, then keep your lift under .500". I'll post more later tonight from home about what you can expect in terms of where your torque curve will peak with each cam set.

Shu, the 883 heads are 04 versions. I am taking out the 7mm valves for soem 5/16 units set up to .550 lift. I am not going anywhere near that lift. Besides the 04-05 stock springs supposedly can take the .551 lift cams without a problem but someone here has already had a problem with the .551's unfortunately.

As far as torque goes, I got 79ft lbs @ 4500 with my N2's and 81ft lbs @ 4000 with my N3's. Also got 84/83HP @ 6300 respectively. I'm pretty sure that these 883 heads will improve the torque numbers. Don't care if I don't get more HP but hope I won't loose any either. The XB heads are so big that my velocity should increase signifcantly with the smaller ports and valves. Only time will tell.