CB I didn't know I had any issues until the day you text me showing me the pushrods and shims. That was the day I pulled my heads and saw I touched off in cylinder one. Mine has been a solid combo, and now I know to cut the pushrods down.

Sent from my XT1080 using Tapatalk

I know Owen. Again, I'm not pointing any fingers at anyone. Just saying, we know now there are potential problems, yet if you look at this thread over the last couple weeks since everyone has known this, you'll still see the same old stuff. Nothing noting any issues. There is a guy putting together a motor right now with these parts that had no idea nearly everyone running them had an issue at some point and time.

We have to share the bad with the good, or this does not work.

Eat a dick, guidry.

K fellas keep it clean no bull shit or dik eating here that will mess up thread lol

I have been researching and questioning since I first saw this thread. I knew someone would eventually come up with a problem. Hopefully we can all use each other to find the necessary solution.

CB seems to have a valid issue with the lash screw falling off the stem. I took a cover off earlier to start getting ready to measure clearance. When I look at the way the intake rockers move, I can see that its very possible to happen on mine as well.

I had an idea that popped into my head when lash caps were mentioned. The is not currently enough space for caps, not any actually. I first thought maybe a slightly longer valve stem would be the answer... But what if we found another set of retainers with a steeper angle, setting the keeper slightly lower. This would allow space for a cap, and give slightly more pressure.

Sorry for being a broken record. I have a tendency to repeat myself until I feel like it's sinking in. And I really don't want these guys to be mad that I'm questioning things. I want more info. We can all use it...

I like the lash cap idea.. my concern then is coil bind. There isn't much clearance as I sit now. Look at the pics I posted. Remove the shim, drop the retainer...How much effort is it really worth to try to shove a square peg in a round hole? If we make it through the weekend of the fun run, we have a week at the lake to try to break em. If they break again, we're going back with stock cams...fuck it. Maybe a year down the road, we'll try another grind.

I see now what might have gotten your dander up cb. I posted an "it's all good" reply here the other day about the progress of my engine after you've been dealing with a fuck up. I see now that I unintentionally neglected your plight. There's a lot of good points to be had from everyone's experiments as we get further along. Different approaches to the build are whats going to eventually find the limits of the design whether that's good or bad. So far it's been good. Where I'm from broken records are kept around when they still have something good to share, to which I must admit I'm damn tickled to see we're back on a positive track.

Wasn't any one post in particular...and my intentions were not meant to be negative, just informational. My delivery comes across harsh most of the time...it is what it is. I do appreciate all you guys have done this far, and all of the help I have received, both on and off the forum. I just want to prevent anyone else from having a catostrophic failure, and there is a lot of stuff being talked about outside of this thread that's pretty important to those still in the build phase... I wasn't planning to make a post about what happened with ours until we got back up and running and are really able to put them through the ringer, but there has been quite a few posts since then on this thread that are implying that everything is perfect, and the simple fact is, it just isn't. This stuff needs to be talked about. I know it sucks, but it's important. Trust me we aren't happy about it, but if sharing what happened can prevent someone else from having the same issue, I"ll post the same shit 100 more times...

When this project was in its infancy a VERY well respected race engine builder expressed his doubts about the intake rockers weight and their ability to handle high rpms. Had a lot to do with inertia, mass and such , anyway I believe this combined with the lobe profile on the Dyno mod 1 grind is prolly why this is happening. Just my theory... I do think the geometry can be improved though and indexing the pistons is a fairly common practice in race engines to allow for a higher lift cam.

I still don't see the need for indexing the pistons. I can't get my valves anywhere near them.. Our failure was due to rocker geometry. The adjustment screw fell off the valve stem and pinned the valve open. There is no doubt in my mind about that. With the extremely small cross section of the valve stems, there may not be a really awesome solution for that in this application. There is just too much travel to deal with and not enough surface area. We have the "open valve" position figured out, but I'm not super happy about the "closed valve" position. Have you looked at my pics? What are your thoughts?

I have looked at the pics and the one with the broken boss has me perplexed. That's the old style head? The pin head "should" be facing the camera is what I mean but the boss for the side with the head has a step to keep it from spinning... My thoughts are that high rpm valve float causes the tappet to leave the cam lobe at the peak which shoves heavy pushrod and heavy rocker so hard it overcomes the springs even when almost fully compressed. Of course when the rocker tip jumps off the stem your screwed. If the stems had any more space between the ends and the keepers this would be a lot more disastrous. For those of ya not familiar with valves floating, it can happen two ways, one is when the spring allows the closing valve to bounce on the seat and the other when the springs cannot keep the lifter in contact with the cam lobe at max height. More spring pressure, less radical cam profile or rev limiter are the three cures. The rest (geometry) is basically perfecting the recipe.

The broken one is the old style, yes. And I agree with all of that. Valve float caused the adjustment screw to pop off the valve stem, pinning the valve open. I believe the others who have touched off have had the same issue, but have no way of knowing for sure. I believe they've been lucky enough to pop back on the stem without major damage, but also believe they're playing with fire there if no correction is made.

My question is what are your thoughts on the correction? I definitely like where we are when the valve is open now, but not super excited about where we are when it's closed. We're coming down at an extremely steep angle. We think we'll be ok, but won't know until we try. I think worst case we bend a valve this time because of side load, I don't think we will fall off again on either side. I also don't know what we can do to make it any better. Obviously, you understand my concerns with using a slightly longer push rod to make the starting angle better, as that puts us back closer to the edge we've already fallen off of once.

I really want this to work as we've invested the time and money in it now, but I'm just really not sure with the little valve stem and huge about of travel, we'll really ever be able to come up with a really good solution.

There was literally no room for error on the valve stem man. Like, .012 more lift and you're off the side. The 308 wouldn't make u much safer..

No on the longer pushrods for sure. I hate to say it but if you're set on running that cam it's going be even higher spring rates which I'm not all warm and fuzzy about or a limiter. The one I've been procrastinating installing is a 5200 max and will work exactly like the Briggs by cutting the coils out. I think the limiter was about $60 and even if we have to incorporate a pickup (proximity switch) it won't be as much as another cam.

Our failure happened at around 4500 rpm's. First trip out. Deep water. Just easing into the throttle watching an a/f meter while trying to tune the carb. We were using the century springs, not shimmed. We have now switched back to stock springs, shimmed, and locked in place with the locators we made. I would like a rev limiter, but it would not have prevented our failure.

I'm not "set" on running the cam...it's just all we have at the moment. We will try to break them after next weekend...if we can't we're likely gonna keep rockin it. If we do, I think we're going back to a stock cam for the time being.

Sorry I keep asking, but what do you think about the starting angle? Valve closed? Does that concern you? A lot? A little? My machine shop guy thinks we'll be fine there if we have no intentions of turning past 5k, which we don't, but he didn't really like it, and I can't say I really do either...

Ok. This is really getting out of hand and I'm getting calls from all sorts of people that don't have issues.

Ok the reason I indexed my heads was the simple fact that I wanted to get my clearances back. That's it. It has nothing to do with touching off, nor does it have to do with the additional Decking. I wanted it. ME that's it. By indexing my piston, I negated all the DE king that I had done and basically got my stock clearances back.

Now part 2. Take into consideration that I have,the fastest kawi with the .310. At no time did I loose power or notice any drop off when it touched off. If T chauvin hadn't Decided to deck an additional .025 to a total .050, my ass would still be running those heads as is. With the touch off. At no time did my rocker geometry come into question. My geometry was dead nuts with .025 decking, but when you accedently spin it 6000, shit will happen. I was also the first to run a kawi with the .310 and also the first to run it with stock springs.

Which brings me to another point. The stock springs from one motor to the other have varied. Mine stock were 18 lbs. Mikes were 15. He'll he had one head that had a 12 and a 15 lb intake spring.

TC was the first to notice that by decking .050, the rocker geometry was out of wack. That was about 3 weeks ago. When I Decked mine to .050, I noticed that the geometry was a little off. Prob still runable, but I wanted it better. So 1.5 weeks ago, I decided to get my geometry back to dead nuts. While mine was good at .025, others have had close calls.

Now to CB, because we have talked several times on the phone trying to figure this out. In this entire build, each engine has acted different. All 6 have never acted the same. Even when doing the same cam. My jetting is totally different from lees and totally different from TC'S and Jerimiah. And the was done with a meter to check jetting. The heads are different. There is no "legos" just to bolt on. You have to have some engine work ability to work on these so those that are just putting it in there without even a PM or any other communication. So if they did that, then oh well.

To everyone. Anyone who has contacted me about this engine or the briggs has gotten true information. Never once have I steered anyone in the wrong direction. This was a project. Just like with all, you are bound to run into problems. I DIDN'T, but when you spin it 6000, that's my fault. Again, mine was totally fine. It's just my .310 +4 didn't have the low end of the stock. So Decking more would have helped yhat. The same goes for the briggs. When they were Decking and getting stupid compression numbers, something will break or you will bend pushrods. This is the same. We decided to pioneer a new engine to give people options. But it's up to them as to wetter or not they want to do it. All are different and each will need it's on special items. There not the same. He'll my pushrods were SS. Mikes were aluminum and we bought them the same day from the same place. So if you truly have questions, ask, don't just fuckin bolt on something because of what others have. Know,you engine and adjust and add accordingly.

Here's mine

I sent pm's. I talked on the phone. Sent text's. Took the parts that were suggested to install. Broke the first time out. Made a few more calls. Found out extra things were done with said parts before installed. Found out others had pistons crashing into valves. Tried to figure out why. Tried to figure out solutions. Wanted to run them first before making things public, but got frustrated watching the chest thumping going on in this thread knowing there are issues. Issues that even over the last day since I brought all this up, it seems some are still ignoring, or blaming on something else, with no logic to back up their statements.

I'm talking to a guy who has sent the same texts, the same pm's, and is installing the same parts...he had no knowledge that so many people running these cams had pistons crashing into valves. No idea people were having geometry issues. That's my point in all of this. Just keep saying everything is good, it isn't man. It just simply isn't. Pistons hitting valves due to over revs, or the reason I believe which is falling off the valve stem...either way, it's something that needs to be addressed. Nobody is being warned of these potential issues. I agree you should have some know how if you're going to venture down this road, but it's awfullly nice to have the guys steering the boats give you all the information they have so you can make an informed decision. The simple fact is, there is a lot of missing info here. If there are clearances people need to look at, geometry issues they should be aware of, let them know man. You know they need to look at this stuff, but you don't tell them. You tell them your motor is a beast and act like you didn't bend valves and bang your pistons into the valves. You tell them to buy springs that will work well with the cam you suggest, but don't tell them that you shimmed them. and that the stock retainers don't really sit on them properly.

Don't paint half the picture and call it a picasso. There is some pretty serious stuff here that needs addressing. I'm just trying to get it all out there. You can't say, buy this, buy that, it's a good setup, 'MERICA! ....then when something breaks come back and say oh, well, we recommend a cam that gives you less than half the recommended p2v clearance, rocker geometry is fucked up, and the springs for the cam don't really fit and need to still be shimmed, you shouldn't have messed with this stuff if you don't know what you're doing...If you know all the springs are different, people are banging pistons and valves together, the clearances on the cam are too tight....why keep suggesting the same stuff? Not only keep suggesting it, keep suggesting it without a warning of potential issues?

Hmmmmm? I believe CB5331 is more pissed off at someone other than me.

Cb it is possible that stock springs are better I ran a 335 lift with stock springs only failures were with aftermarket springs but shortening push rods does help the other motor I sold that knocked the retainers off had century springs and I really wasn't comfortable with those springs the walked around a lot .

Cb you are acting like someone purposely mislead you when in truth he really didn't know what the problem was be careful this hole thread can be deleted some of these guys are just experimenting they are not professional mechanics I think everyone has just realized what the problem is . I'd hate for people to get offended and no more info period gets posted I know you don't mean it and maybe you don't understand that the person may not have had the problem or solution figured out yet . But according to the group of guys on the post if it keeps going south this thread will die I hope you can see what I'm saying .i personally don't get on here much cause the others communicate with me through text but if you feel like you feel I can't help that good luck call if you need anything.

No. I dont think anyone purposely mislead anyone. Sorry if i come across that way. I am not pissed off at anyone. I am frustrated that so many important pieces are missing from this puzzle. Pieces that are available, or at least known to exist. There are many things now known that are being ignored. Its like they refuse to recognize there is an issue. Bending valves and smashing into pistons is an issue..does anyone disagree with that? Why are we acting like its not an issue? Why are we mad because i put it out there? I want to solve it... And i'd like to solve it here where everyone can see it. Lets talk about it...

I'm not trying to be mean. I'm not attacking anyone. This thread doesnt need to be removed because i'm trying to add info. If it gets deleted, it just proves that we can only talk about the good...and if thats the case, this thread, this whole project, is a lost cause.

DEFINITIONS OF:
tactful
1
adj having or showing a sense of what is fitting and considerate in dealing with others
“she was tactful enough not to shatter his illusion”
“a tactful remark eased her embarrassment”
Synonyms
considerate
showing concern for the rights and feelings of others
discerning, discreet
unobtrusively perceptive and sympathetic
Antonyms:
tactless, untactful
lacking or showing a lack of what is fitting and considerate in dealing with others

I'm trying to be patient here. The rockers didn't just fall off the stem. That's about as general a statement as I can imagine, how the heck does that occur? I've seen my tach flash stupid rpms and I promise you that unless you had those valves ridiculously over tight that happened prior to cruising along at 4500 and that boss cracked at the same time as the chip it just happened to give up at later because of the pin and boss design. I didn't start this as "A blueprint for repowering with Kawi engine" just as a means to share what I've found as I worked it up. Nobody has withheld anything (hell I can't remember half this crap everybody's done) and I'm convinced the only way for this to happen is over revving with that cam combo. Having said that you seem to have or be working with someone with some good engine knowledge that I hope can be shared.

I'm gonna share a story that I think is relevant.

About 20 years ago and fresh outta the army I had a Chevy with a B A D A Z Z big block that I spent most of my money building with all the good stuff and that beast would naturally boil 18-44 Ground Hawgs! One day after piddling with the carb I took her for a spin and show off a little and when that bad sumbuck got its breath the damn throttle stuck WFO!!! Well boys things were fixin' to get bad messy and I sure didn't wanna hurt anybody so fish tailing like hell all I could do was step on the clutch... Well when I tore that engine down about 12 pushrods ends were beat to hell, cam was shot and most of the bearings spun. Big block Chevys aren't designed to withstand that kind of rpms! Especially goin' from a loaded to unloaded condition and neither are commercial v-twins... That was a very expensive few seconds of my life!

Bugs the first engine I put the 310 in knocked retainers off after hitting something in water and over revving I think those century springs need to be checked out also see what going on might be a weak link

And you don't have to hold your tongue or be patient with me bug. If you got something to say, say it. I want to have the discussion. I enjoy learning. Right or wrong, good or bad. If you can teach me something or disagree with something I've said, say it. I'd already said several times that the screw fell off the stem because of float, but if you have another theory, lets hear it.. I don't see any other way for the pistons to hit the valves unless the valves are stuck open, and I don't see that happening because of slight valve float. Neither do the people who have been trying to help me come up with a solution to prevent this failure again.

I see now what CB wanted: He was, at minimum, entitled to a peer reviewed research paper on the modifications before he tested them. Dang the nerve of the others not providing it. Y'all ought to be ashamed.

Why don't you go eat a bullet?

Dude, contribute or go the frack away. They're trying to hash some things out, and they will. You aren't useful here with that pot stirring crap. We finally have a useful post with some valuable information, with more being added. Grow up and quit with the ninja shit.

I have ninja credits I have to use up before they expire.

CB. Use more :lol::lol::D:D:D:D;);););)