View Full Version : where to get aftermarket cams for 16a1
KaBlammyman
09-20-2003, 02:43 PM
Where can I get some aftermarket cam shafts, cam gears, valve springs and retainers for my D16a? Am I able to somehow use 2 SOHC cams? Any info would be appriciated.
UnhuZ
09-23-2003, 02:21 AM
Well iīve been using ebay and canīt complain about it...
And you have energy dinamics site as well
you can use ZC cams in a D16A1 - stock ZC cams have roughly .040" more lift than any 86-89 D16A1 cam ever did. HOWEVER, you absolutely must have adjustable cam gears with at least 10* of adjustment in order to use the ZC cams in the A1.
The reason being that the rotational relationship between the cam key and the cam's "straight up" position is different between the ZC and A1 cams. ZC's use 34T cam gears where A1's use 40T cam gears. In order to compensate for where the teeth on the different diameter gears fall for the belt to be tight between the cams, the keyway is in a different spot on the cams.
I just went though all this with my D16A1 using ZC cams. The cam gears are my own design & manufacture, so I can't suggest where to get cam gears other than AEM. You just need a pair of any 40T cam gears.
Moving along to your question about springs & retainers, unless your A1 springs aren't up to spec., you can simply put .060" shims underneath the stock valve springs to raise the seat pressure without coil bind. Nothing is going to outlast the stock retainers so I wouldn't bother changing them, especially if you are thinking of going with titanium (Ti retainers are a wear item - they wear out).
strudel
10-15-2003, 09:55 PM
TJ, Can the keyway just be re-aligned in order for the stock cam gears to work on the ZC cams? I make the assumption that one has to remark the AEM gears if they were used because the difference in diameter. Does the difference in diameter not change the rotation speed of the cams. Even using the ZC cams and gears the rotation would be off, wouldn't it. I'm not a master at this that is why I would like to learn more about it. Thanks.
I don't believe that the keyway could be reground to match the D16A1 cams - the difference in degree's isn't far enough away...Unless you ground keyways 180* from the stock D16A1 position and ran the A1 cam gears upside down.
You could re-mark the cam gears, or just write down what numbers are true zero with the cams straight up - install the cams using the M5 dowels, leave the gears loose, set the belt tension, verify the TDC mark, tighten the gears. If you think about it, the markings on the cam gears are only relative numbers, so if your intake cam gear reads +4 when it's really zero, then +5 is going to be 1 degree advanced.
Now, what I found when using the dowel method to find where the cams were at true zero was that the registration holes in the cam caps are 5.5mm, or very nearly 5.5mm since they are cast pieces. The counterbores in the cams are 5mm. With a 5mm dowel going through the 5.5mm hole, there is roughly +/- 2 degrees of "slop" (about 4* total). To remedy this, I first ran a 5.5mm drill through the caps to clean up the holes, and then made some custom stepped dowels with a 5.5mm diameter to match the cam caps and 5mm at the end for the cam. This greatly reduced the slop-factor to less than 1* total.
To answer your question about the difference in cam gear diameter and cam speed - NO! Remember that every 4 cycle engine must operate with a 2:1 crank/cam ratio. It doesn't matter what the diameters are as long as the cam pulley diameter is 2x the crank pulley diameter.
A D16A1 has 40T cam gears, and a 20T crank gear. A ZC has 34T cam gears and a 17T crank gear, so the relative cam speed is exactly the same.
I had considered using ZC cam & crank gears on my D16A1, however the one difference between the two motors is that the ZC & D16A1 waterpump pulley's are not the same diameter. This throws the belt length off. I'm not exactly sure how much, and I don't know if there is enough motion in the tensioner to take up the difference. I haven't totally ruled out this option.
If anyone is willing to send me a ZC timing belt and a timing belt crank gear, I can try it out! I already have a set of stock ZC cam gears...
This would open up a whole world of adjustable cam gears since the ZC cam gear is the same size as a B series cam gear.
strudel
10-16-2003, 09:34 AM
TJ, Thanks, that explanation makes it clear as mud as I didn't know the relationship between cam and crank gear. If belt length is the only problem I just read a thread about that here:http://www.redpepperracing.com/forums/index.php?act=ST&f=2&t=3563&hl= It appears to be quite the swap. The fellow alludes to the initails TJ throughout, would that be you by any chance?
The reason I am curious about these things is that I am putting an 86 D16A1 into an Austin Mini and am compiling an info package for myself from various boards that can be used when the time comes to rebuild the engine. Hopefully it can be increased in HP for less money than buying a B series and anything over 100 HP in a Mini is a blessing in any case!
KaBlammyman
10-21-2003, 04:17 PM
wow, its been a while since I been back here cuz my question was not an easy one to answer, but I'm glad someone knew the answers! :D Anyway, to recap, I can use ZC cams with AEM cam gears(or some other adjustable aftermarket gear) set to at least 10+ degrees, and leave the rest of my head, stock? Is this an accurate summary? Anymore info would be appricated. Also, is there anything else on the ZC "better" than the D16A1 (browntop) that I could swap in there? ...many people wernt 100% sure on the yahoo e-groups about what internals would benifit a D16A from a ZC. I just like the idea of semi building a D16A1 wth ZC parts rather than just buying a ZC...even though I will get a ZC eventually. :wink:
Yep - I'm the same TJ mentioned over at redpepper. That's my friend Kirk who's put the DOHC head on the old 84-87 block. He designed that extra tensioner instead of trying to find another belt that just happened to be the right length.
It may be possible to mount the same kind of 2nd tensioner on the D16A1 if you are going to use the ZC crank and cam belt pulley's. I made that tensioner bracket for him, so if you collect the appropriate ZC pulleys and want to try the dual tensioner, let me know via e-mail and I can machine one for you. My email address is schmtj@ispec.com
Just remember that you need to get all three cam belt pulleys - running just ZC cam pulleys with the D16A1 crank pulley would spell disaster in about 2 revolutions of the engine.
Anyway, to recap, I can use ZC cams with AEM cam gears(or some other adjustable aftermarket gear) set to at least 10+ degrees, and leave the rest of my head, stock? Is this an accurate summary?
Almost accurate. You need the adjustable cam gears with 10 degrees of adjustment - don't set them to 10+ degrees!
When you install the ZC cams and go to put the belt on, do it this way to ensure that the cams are set at zero relative to the crank:
-install the cams using the M5 dowels that are referred to in the Helm manual
-leave gear's adjustment loose
-install the belt
-set the belt tension
-verify the TDC mark on the crank
-tighten the gears adjustment
If you think about it, the markings on the cam gears are only relative numbers, so if your intake cam gear reads +4 when it's really zero, then +5 is going to be 1 degree advanced.
To really make sure that the cams are very close to zero, pay attention to this next part!
Now, what I found when using the dowel method to find where the cams were at true zero was that the registration holes in the cam caps are 5.5mm, or very nearly 5.5mm since they are cast pieces. The counterbores in the cams are 5mm. With a 5mm dowel going through the 5.5mm hole, there is roughly +/- 2 degrees of "slop" (about 4* total, and that's per cam!). To remedy this, I first ran a 5.5mm drill through the caps to clean up the holes, and then made some custom stepped dowels with a 5.5mm diameter to match the cam caps and 5mm at the end for the cam. This greatly reduced the slop-factor to less than 1* total. "
-TJ
KaBlammyman
10-21-2003, 07:01 PM
Thanx TJ for all the info!
strudel
10-21-2003, 09:11 PM
TJ, Appreciate the info and offer of help. It will be a while til I actually tear the engine down as I am just trying to finish the Mini frame for engine and CRX crossmember/suspension etc. Slow process with not enough time to play with it. I will certainly try to contact you in the future for some hands on info as it's always good to have a resource that has done some difficult or different modifications.
I suspect you might already have seen this url on a similar cam installation. http://www.muller.net/sonny/crx/ or are you also the same person as this site? http://www32.brinkster.com/tjshondas/ Just curious. Are you US or Canada based?
Jmorin
10-22-2003, 10:05 AM
Where can I get some aftermarket cam shafts, cam gears, valve springs and retainers for my D16a? Am I able to somehow use 2 SOHC cams? Any info would be appriciated.
Good questions but this is the DOHC ZC part of the forum ,you might get better response outside of this one.
strudel, yes I am TJ of TJs Hondas.
rally25rs
10-27-2003, 06:01 AM
For those of you that have already done this, how many degrees off are the ZC cams in the A1 head? Someone said not to set the adj cam gears to 10 degrees, so what is the correct setting?
Thanks!
My head is still at the machine shop, so I cannot tell you the # of degrees. Also, since my block has been decked and head milled, that compounds what my cam gear settings are in the D16A1 compared to a stocker.
The only ways to set the ZC cams straight up are to use the dowels I mentioned above or a degree wheel.
BseriesKllR
10-29-2003, 11:51 AM
you would have to use 2 8 valve sohc cams but i dont think its worth it
KaBlammyman
10-29-2003, 09:25 PM
you would have to use 2 8 valve sohc cams but i dont think its worth it
im sorry, what do you mean by this...I'm lost...who were you repling too? I understood that SOHC cams dont work in DOHC engines well...but what do I know...
strudel
10-29-2003, 11:11 PM
kablammyman, I suspect it was to do with your original post where you asked about using 2 SOHC cams in a D16A1. Since the valve train in a SOHC D15B2 series came in 8 and 16 valves dependant on model and the D16A6 came with 16 the question is would the lobes line up in the A1 engine? I would guess the 16 valve cam would not and the 8 valver probably wouldn't be worth the regrind effort even if it fit. This is all just speculation on my part. The other question is if they are all the same length and circumference on the cam journals?
atomikpunx
11-02-2003, 10:17 PM
http://www.muller.net/sonny/crx/caminstall/index.html
sonny's cam install explains.
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