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Discussion Starter #1
I did a search but didn't come up with a solid answer...
I know alot of this is specific to each car's mileage, mods, internals blah blah.
I'm getting ready to buy a set of Stage 2 Gude's off of Alllude and i'm going to get a set of nice pretty cam gears to go with them, but is there a nice solid setting to get a little boost (even 5hp would be nice) out of the gears without having to have it dyno'd for 6 hours and a grand later?
I have a bunch of mods and i think the cams will help out now or eventually when i get the turbo installed.

Is there a nice set retard/advance for each cam that anyone has come across that they like with just a handful of bolt ons that won't dick my car to hell, or perhaps someone has done the dyno route and found a good number to put them at?

Thanks in advance kids,

Danny
 

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well for great top end but worse bottom end, you should increase the valve overlap. you do this by retarding the exhaust a couple degrees and advancing the intake a couple. say, 2 degrees each way. your idle will suffer since you are blowing some of the intake air straight out the exhaust (due to the overlap). i increased my overlap by 4degrees total (-2 exhaust, +2 intake), i have no clue what kind of gains or losses you will see if you change them to say -3, +1, or -1,+3 etc... but FYI more overlap on a turbo'd engine is bad, because it creates "turbo chill" since you are sending the cold intake air right out the exhaust.. turbos like hot air.
 

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Well see the problem is that also the reground cams aren't always set a 0deg. they might be a couple degrees off so what for somebody might be 2 positive and 2 negative might be 1 neg and 4 positive for your because your cams were ground 3 degress negative off zero and 2 degrees positive off zero, intake and exhaust respectively (maybe not that extreme but you bget what i mean). your best bet is to get it tuned. I know its expensive but its way worth it. I'm not sure if our engines are interference engines but retarding or advancing them too much might cause bent valves.
 

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Well that's why you always turn the engine by hand before you start it up. Then you know for sure, yo.

--J
 

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Discussion Starter #6
Thanks a bunch guys!

I'll see what happens and warn everyoen if something blows up!
Haha... "don't do +this -this =p~~"

Danny
 

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Keep in mind that the degrees mentioned are at the cams, double those for the true valve timing, +4 becomes +8, and so on.

Personally, i'd skip gudes cams all together, their powerband doesn't match the b20's redline at all.

That said, increasing overlap should benefit high rpm power (intake valve opening sooner, exhaust closing later), while lowering low rpm power, dialing out overlap should increase low rpm power but sacrifice it at high rpm.


EDIT:
Another thing to keep in mind is that this is NOT a time where "if some is good more is better" is true.

Furthermore, i'd be extremely surprised if you found five peak horsepower from adjusting cam gears, your better off tuning them for a better torque curve then you are tuning them for peak power.
 

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If you ever dyno with the Gude cams and cam gears make sure to post it up. I'd really like to see how Gude stands by his product and hp gain.
 
J

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foilks weve been over this. jump had a huge thread on this and a great explanation.


basically our cars respond to +/- I/E go that route, like one or two degrees and youll make huge mid range torque but nothing else can be ahd form these
 

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the reason we get so much more low end power out of +4/-4 In/Ex on our cars is cuz they have negative overlap. more overlap equals more high end power, but adjustable cam gears can only go so far. and if you adjust them to the above, you create a very mild overlap which is what our motors love for low rpm torque, but the gears cant be adjusted far anough for a large enough overlap to increase peak hp; at least not with stock cams.

as for major overlap if you can mod the cam gears to do so, i dont know what kind of clearance issues you may run into with the valves and pistons, so dont try it unless you really know what you are doing.

as for our cars having negative overlap, meaning there is absolutely no overlap at all, exhaust valve closes a few degrees before the intake valve opens, this was done for better gas mileage and smoother driveability at low rpms. creating a very mild overlap with cam gears and stock cams will lower your gas mileage and tune it perfectly for low rpm torque.

if you want more high rpm power, do some research and have custom cams ground for your requirements. more lift will always help all rpms, as long as you have the springs to support it, and as long as you dont max out the valve compression crushing the springs or hitting the valves on the pistons.

i dont suggest a lot of overlap with any motor, as it destroys low rpm driveability and smoothness in a very bad way, much worse than the gains you will get in the top end.

mild overlap, more lift to an extent, and slightly longer duration will show the best gains overall. too extreme on any of those will totally kill low end power, smoothness, driveability, and gas mileage. so do your research before attempting any of the above. keep an eye out in the next few weeks for my posting of exact stock cam specs for b20a5 cams and b21a1 cams. i am going to buy a degree wheel and determine exact specs myself so i have a basis to go by for what specs i want for reground cams. and so everyone else here will know what exact stock specs are so they can use their own knowledgeable judgment on what specs they want too.

somebody (only one person) posted stock cam specs for b20a5 cams once here before, and they are soo incredibly innacurate that if they were true the motor wouldnt even run. so anything that shows up in a search here for stock cam specs is wrong. at least until i determine them for myself. of course unless someone else here has a degree wheel and knows what they are doing and does it before me.
 

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Discussion Starter #14 (Edited)
Ok so...

+4/-4 would be better than stock? Did i read that right? Or would i be trading high end power to get low end power? I don't want to transfer the power i'd like to squeeze a little out if i can.
Plus can someone link Jump's thread on the camgears?
I searched my balls off and couldn't find it.
Thanks moto that was very helpful!!! And get back to me on how you're going to grind yours cuz i have an extra set in storage that wouldn't hurt to have reground.
Danny
 

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car_boy_16 said:
I can wait...cuz it's not going to happen.
so basically what you're saying, is you have absolutely no idea what i am or am not going to do, and are just wasting space in a thread to make me seem like im talking out of my ass making false promises?
thats cool, you're entitled to your own opinion, but i wouldnt speak if you dont know what i am capable of or planning on doing. very few people have a clue as to what i have planned for my lude, but all i can say about it is that i am taking drastic measures to research every possible aspect of the motor for a proper build. cant build a motor if you dont know much about it. only way to get more power is to determine all stock specs for EVERYTHING and figure out how to improve those specs and match them all for the same rpm range of power. and thats where i end that comment before making myself sound as much like an ass as some other people on here do on occasion *ahem cough cough*


Team Paradigm said:
+4/-4 would be better than stock? Did i read that right? Or would i be trading high end power to get low end power? I don't want to transfer the power i'd like to squeeze a little out if i can.
Plus can someone link Jump's thread on the camgears?
I searched my balls off and couldn't find it.
Thanks moto that was very helpful!!! And get back to me on how you're going to grind yours cuz i have an extra set in storage that wouldn't hurt to have reground.
Danny
yes, you read that right. with STOCK cams, the best setting is +4/-4 In/Ex. it will not affect top end power at all while increasing low end power, as all it does is create a mild overlap verse the stock negative overlap.

it'll be a while before i know exactly how i want to grind my cams, cuz i need to mod a lot of other parts of the motor first then take measurements and crap and determine what rpm everything will be tuned for. cam gears are the last thing on my list of mods. but determining stock cam specs is one of the first things on my list. so expect to see that posted within a week or two. soon as i get down to my speed shop and buy a degree wheel and get one of my motors on an engine stand for testing.
 

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lol, ok, sorry if i sounded rude above then. but i already have enough motication to do it lol. so no worries there. it'll deffinitely be done and posted within a few weeks.
 

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if the above gets merged with this post, the above was posted a few days ago. but anyway, im picking up my 18 inch moroso degree wheel tomorrow. and right now it looks like i wont be working much next week, so hopefully by the end of the week next week i'll have ACCURATE stock cam specs posted for b20a5 and b21a1 cams. and im not just referring to lift and duration, im referring to exact opening point and closing point of each cam/valve at 0.001", 0.010" and 0.050", actual lift with rockers adjusted for the difference in heat expansion in the lifters and valves, and may even try to determine max possible lift before the stock valve springs are completely bottomed out. look for my extremely long post/write-up with pics and all info you could ever want for the stock cams sometime next week.
 

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Amaymi said:
I'm not sure if our engines are interference engines but retarding or advancing them too much might cause bent valves.
yes they are interference engines, my friend snaped his timing belt and bent his valve and craked the piston
 

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motoxxxman said:
if the above gets merged with this post, the above was posted a few days ago. but anyway, im picking up my 18 inch moroso degree wheel tomorrow. and right now it looks like i wont be working much next week, so hopefully by the end of the week next week i'll have ACCURATE stock cam specs posted for b20a5 and b21a1 cams. and im not just referring to lift and duration, im referring to exact opening point and closing point of each cam/valve at 0.001", 0.010" and 0.050", actual lift with rockers adjusted for the difference in heat expansion in the lifters and valves, and may even try to determine max possible lift before the stock valve springs are completely bottomed out. look for my extremely long post/write-up with pics and all info you could ever want for the stock cams sometime next week.
Yeah, whatever dude...all I hear is blah blah blah :tongue: JK JK!
 
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