KAZ24 build thread / compression questions / cam / header / DONE!!

[HRH]

Oh yeah, the drivetrain vibration came back! Here's the deal. During the trip down I got mad vibration. Followed by the trip to Firestone in Oregon City the first morning of Canby, and then by the u-joint changing after that. Got home, was still doing it. I banged my head and went through every system I could think of and kept arriving at the tires.

 

Sure enough, I spent most of the day at Firestone back here today. A week ago I rebalanced the tires on my balancer. Took them by today and sure enough they were out. Had them rebalanced, then went and mobbed around. Came back a half hour later, sure as shit, out of balance again. So got two new BFGs (warrantied) and NO MORE ISSUES!!! I looked at the old (month old) ones once we got them off the rim. Rolling the tire, I could see the inner casing flexing like a snake rippling back and forth. No worries on the outside of the tread, but sure crappy inside.

 

So all the vibration issues I had were caused by brand new tires. Cool weather it was barely noticeable. The recent hot weather made all the difference. Been driving all day on the new tires, no more vibrations. Way way more happy. Kept thinking somehow my motor modifications had screwed something up, but fortunately that was not the case.

[datzenmike]

Good for you Matt.

[HRH]

Why thank you Mike! I'm just glad I'm not going insane. I literally can't just turn up the radio and tune it out. The horrors of mechanicing. ;)

[HRH]

So my cam is out for delivery according to the tracking thing on USPS!! Can't wait!! I'll be posting up a dyno sheet before and after as soon as I get the new cam in.

 

GOT IT!!! Looks beautiful! They even parkerize their regrinds at Colt Cams. Have to remove a motor on a truck I'm working on for another fellow. If I get that done in time, I may install it tonight. Not sure yet.

[HRH]

Update update, get your update! So I'm pretty much finally done screwing around with the D21 unless I get the 510 done and then decide to turbo the truck. ;) Anyway, my Colt Cam came yesterday, ending up installing it today. Pretty stoked, the result wasn't quite as exciting as I had hoped, but it was still pretty good. I wanted to remain mostly stock since I don't run the truck at high rpms and I like my low end torque. Don't notice the torque that much so far, but the high end hp has definitely improved. The dyno will tell the real story. Looks like I'll get to dyno it sometime next week to compare the before and after.

 

To recap from the beginning of this thread, we have a custom KA head/Z24 bottom end with approximately 9.3:1 compression, header with 2 1/4" exhaust, opened up airbox with drop in K&N filter, and now a C499H grind cam from Colt Cams in Canada. Beauty, eh!? ;)

 

 

 

 

 

 

[HRH]

 

 

 

 

 

[HRH]

 

 

 

 

[HRH]

 

 

 

 

[HRH]

And here are some videos!

 

 

[Farmer Joe]

its got a much grunty-er sound to it..

 

like its ready to pull shit around.. lol...

 

it pulled like mad with the stock cam goin up that hill outside canby... makes me want that z24 so much more..

[HRH]

 

Alright! As promised, I finally got a chance to dyno the truck again today. The numbers were.....not as impressive as I'd hoped. However, there was also a 30 degree differential in temperature from the initial dynoing sans cam. Needless to say I'll be doing it again when the weather cools off. I know the truck is ten times better just from driving it around and the ability to lay rubber much better than before.

 

I'll give you the eye candy first before the technical bits:

 

http://www.youtube.com/watch?v=q3zw9e0ViE8

 

And now, the technical bits:

 

 

 

 

 

 

Note on the top end, the fuel trim is waaaay too rich. Most factory maps are like this to err on the side of caution. Better to be rich than lean and blow the motor for warranty purposes. Joe is planning on installing an adjustable fuel pressure regulator on his hardbody and tuning it for mileage. Depending on how that goes, I may do the same on mine to get the ratio better. A solution would be a standalone engine management system with tweaking abilities, but in the interest of Ratsun level cheapness, it may prove to be just as effective for the overall goal of mileage or power. We'll see.

 

Before we got there, Joe had drug out Katherine's roadster for shits and giggles. Has a Z22 in it, posted some decent numbers for being neglected. Had about 5 year old gas in it too.

 

[DAT510]

Yeah I was gonna point out the AFR...

Don't engines make more power... leaner?

 

If a cammed KAZ24 sounds like that... I want one.

:lol:

[HRH]

Follow my instructions and you can indeed have your own! :D

[datzenmike]

Engines make more power if slightly rich. You can only use as much of the gas as there's oxygen to burn with it... the rest just goes to waste. BUT the extra fuel absorbs heat as it evaporates and cools the air down which reduces the chance of detonation. You can run more advance and compression to get the most out of the motor.

 

Nice sound.

[HRH]

Yeah, but it's waaaay too rich. I think getting it to about 13.5:1 afr on wot would be a lot better than the 12 it sees now.

[Sealik]

Yeah, but it's waaaay too rich. I think getting it to about 13.5:1 afr on wot would be a lot better than the 12 it sees now.

 

Hmmmmm...I don't know.

12ish would be best for WOT....most power, slightly rich?????

14ish.....idle

Cruising 14-16...relative to throttle position/load

[datzenmike]

Doug's right 12 would be better that 13 for most WOT power. High14s and above for idle/cruise.

[HRH]

Hmm, found this interesting tidbit on the web.

 

http://www.sdsefi.com/techegt.htm

[datzenmike]

Well try 13 then and see if gain or loss, but be ready to try 11.5 . Richer may allow more advance too because it will run cooler.