3.0 Build Project: "Green Machine"

[paduster]

the 10:1 pistons are just that pretty much flat top i have a set now

[shayne]

okay, so.
the basic piston part number for a 6g72 is, 3620, 92.1mm bore
i got the m1000 pin fit
5000-866 pins (.866)
k (custom ring set)
m1004 pin oilers
the job number is 135824, and dale was the salesman. iirc the stock piston and wristpin was 30grams heavier than the forged pistons with wristpins.
thats all i got on the workorder, on the copy im looking at the prices are blacked out. but the price is in line with other companies i called and their staff was super professional and helpfull, i actually got a call from the guy doing the machining on the dish of my pistons to clarify what i wanted before he went ahead and cut it. just sayin. hope this helps.

[MC#4]

Thanks for that info Shayne. I'm not 100% sure what some of those numbers mean but it should be a good starting point. I'll have to give them a call and see what we can work out.

[MC#4]

Hit a couple snags here lately but the project is still moving forward. I dropped my block/crank off at the machine shop about 2 weeks ago but they are slammed with everyone doing winter builds and are finally getting around to my stuff. They did get the crank done and I picked up my valves today, just had them do a quick backcut.

I talked to the owner of the shop about forged pistons and he called me back today about having some made up. He uses a company called race-tech based in california. He told me several success stories about cars making waaay more power than I ever will and they are a bit cheaper than venolia. The quote he gave me today was $675 shipped w/rings. He's sending them a piston for dimensions and I'm having them go with a flattop with 50% valve relief depth. With my combination I should be sitting anywhere from 10:1-10.5:1. I had the heads milled earlier this year and the block will be getting decked shortly.

Got an email from RPW the other day stating that they CANNOT modify Chrysler cam gears to make them adjustable. I shipped them around 11/12 and just got this info. Luckily I have plenty of time for this build but its just an annoying distraction. I bought some mitsu cam gears on 3si for cheap so I will just send those down for modifying.

Transmission is completely dissassembled, got the case all cleaned up today and have several rebuild parts on hand. Gotta snag a few more though, I was looking over the intermediate shaft today and noticed 2nd gear dog teeth and synchro ring are showing wear. I was getting a slight grind when slamming 2nd at redline so I kinda expected this. Now I have to wait for parts to put it all back together and I'm getting a little nervous because there are parts EVERYWHERE.... I wanted this back on the road by christmas, now I just hope its ready before spring...

[Reaper1]

How can they not be made adjustable? How is it I have a set and so does Brent? I think they just don't want to. For a company that does some crazy stuff, I find it hard to believe what they told you.

[MC#4]

They said they were out of cores so I would have to send mine in. The Chrysler cam gears are pretty different than the mitsu ones. I've seen brent's posts that his are mitsu style. From what I've seen the mitsu gears are more like a cast piece and the Chrysler ones are stamped steel. I thought everyone before just bought modified gears as opposed to sending units in to be modified?

[nmw2006]

I have a set of RPW's adjustable cam gears as well. They are NOT made from the stamped Chrysler gears. They modify the cast Mitsu gears to accept a new center section, which makes them adjustable. I got the same message from them when I sent in my cores but since they didn't specify which gears to send they just chucked mine out and found me (for free) a set of Mitsu gears.

[RoadWarrior222]

^^^^ It was him.... peed off RPW and made them change policy..

[Reaper1]

LOL. Honestly, it's been so long that I forgot the Mitsu version was different. I still find it odd they can't figure out how to make the stamped ones adjustable.

[Sundance 6g72]

you know the pin that holds the cam gear in place? The washer with the little nub on it. you re drill a hole in the cam gear that will allow that washer to fit the cam gear at a different angle.

I havnt looked at them in a while but thats how i remember it being done. Ed didnt really have much luck with it and Brent never really hard any big gains he was happy with when he had the real deal cam gears from RPW. I guess it just depends on the cam your running and where you are reving. I also think its not as big of a deal on sohc motors. I know DSM guys are setting their intake and exhaust cams differently to do something fancy but we dont have that luxury.

[RoadWarrior222]

I figure that would work better if you could dial in on loaner adjustables then machine your gear to the right angle.

[c2xejk]

Actually, there is a noticeable change by advancing and retarding the cam. I was actually thinking about advancing one cam and retarding the other to balance the two banks.

You need to keep the pin tight. I carefully ovaled the whole till the pin move the desired amount (I will leave the math to translate degrees to inches as an exercise for the reader.) Then put a small weld on the other side and filed that down till the pin fit nice and tight.

[Ondonti]

I think I bought mine for who knows what reason and I never had to provide cores but I stupidly bought through a middleman which took forever. I had to directly contact RPW to get the order finished.
I ran mine advanced thanks to the big cam not being able to hit peak hp on a stock rev limiter. If you have seen my dyno sheets with no hp drop all the way to 6200 on a stock ECU, that was with the cams ADVANCED 8 degrees. I ended up running those cams straight up on megasquirt and it was nasty until the crankshaft bent when I popped an oring and at some point the motor must have hydrolocked at high rpm.

I believe your camshaft should be ground to work properly the first time and should be designed to work straight up. Cam gears help when you have hack cams or catalog cams. Most people do. I am basically stuck with the cam gears on my fun cams because I snapped a pin off one long ago on the very first driving attempt (blocked oil hole) and the ghetto replacement I did myself doesn't work well with stamped gears.

I posted long ago that the RPW cam gears are very heavy so you really need a good reason to use them. I believe the Lozier style cams are ground to (for some bad reason) need to be advanced. I guess the one reason for changing the cam timing might be for minimizing the material removed from lobes to achieve whatever profile was desired. Mine have too much removed and too much lift. Smashes VSS with solid rockers and overextends and breaks hydraulic rockers while mushrooming the valve stems.

I don't know if cheap pistons are that scary when you are on a budget. Forged pistons with rings is a great thing though. I had a bad experience sourcing my rings separately from my pistons. Forged pistons can take a beating but they can't survive one little spark plug breaking. Nothing can. Make sure to change your plugs based on your pill size or boost level! Also, just because you have forged pistons doesn't make it a good idea to run small ring gaps.

I am not in the position to push my reringed Holset setup to the point of breaking until I own a garage but I believe they can handle a LOT of abuse with big ring gaps. A lot more then the 108mph I ran. Especially with MS keeping timing safe. I don't particularly think cheap pistons will fail any quicker then OEM because we don't have preignition problems (melted pistons) and the only failures I have seen are ring gap related (seizing in the bore and ripping off ringlands). As long as you don't have piston melting problems, I don't really think of pistons as a weakness. Most non mitsubeefy motors suffer rod failures etc at low HP levels so they end up needing all new parts to make decent power and nobody puts stock pistons on baller rods that I have ever seen (would be funny though). SR20's suffer preignition/melting but are otherwise very stout. Maybe we might suffer this problem (with pump gas) on a motor like mine that won't prematurely fail due to small rings gaps. SR20's which are built tough like our motors can handle 15-18psi and they are over 9:1 compression. They melt when things get even slightly wakky. I have never seen a melted 6g72 piston but surely some exist. They have more problems with headgaskets and bearings, mostly due to poor tunes and assembly or bad oil pumps/blocked pickups or just bad luck. Keeping forged pistons out of my life for as long as I can get away with it.

[MC#4]

Wow this project is taking ALOT longer than I thought it would. It's been so bitter cold here the past 2 months and it just killed my motivation. Suprisingly little has changed since my last post almost 2 months ago.

I sent RPW a set of Mitsu cam gears on 1/11/13 and haven't heard a word from them since. I emailed a few days ago but haven't heard back yet. Not really a big deal since I have so much to do but it kinda irks me.

I stopped in at the machine shop yesterday to see what was going on since I haven't heard ANYTHING from them since 12/13/12 when I made a 50% deposit on custom forged pistons. Well just as I expected they had very little to report. The company in California is just now in the process of making the pistons. 7 weeks after I put half down. I was told 4-6 weeks with shipping and they'd be in my hands. Apparently the sample pistons my machinist sent got "put on the wrong desk" and sat there for over 2 weeks! Pretty much just the typical bs you'd expect when working with an engine that no one else does I guess.

I'll admit though there are some things I could be doing to get this project moving, this cold weather really takes it out of me plus we are short handed at work meaning stupid hours and ironically less pay (commission based pay FTL)

As of right now I'm skeptical the car will be ready for the opening day of race season which is the last week of March. That's still the plan but It isn't going to happen unless some pieces start falling into place.

[Sundance 6g72]

GRAAAAAAAAAAAAAAAAaa

[RoadWarrior222]

Waiting sucks...

Last time I had machine work done though, went with a local, dropped it off at 10AM picked it up at 5pm...

[MC#4]

Well opening race day is less than a month away already and still no pistons. Stopped at the shop again today and they called the company. They should be done this week and at my machine shop next week.

I emailed RPW last night and they told me that the cam gears are still being modified. Maybe I'll get to race the car next year... eh probably not.

[Ondonti]

A few races is better then nothing. One little race last year got my happiness level up a lot.

[MC#4]

A few races is better then nothing. One little race last year got my happiness level up a lot.

Yeah I got a few passes in last year and even though the car wasn't quite where I wanted it, I had a blast. Just being at the track is a huge motivation boost, can't wait for the warm weather.

[MC#4]

Sooo, the past weekend was technically the season opener for the local dragstrip but it was cancelled due to weather. I'm hoping to head up this friday for the first night of racing but I will definately not be taking the shadow for a number of reasons. The big one is the fact that I'm still waiting on.... everything. RPW finally finished my cam gears up after plenty of bs. I have to say I'm not too impressed with them and would never order from them again. I submitted the original order waaay back on 11/2/12 and probably won't have them in my hands for about 2 more weeks. Then after all that, they send me an invoice stating that the cost is $20 higher than the website says and shipping them back is $100! + paypal fees. I sent them an email and managed to get shipping down to $75 (still bs imo). So after all the time and money shipping 2 sets of cam gears waiting four months and paying the higher price, inflated shipping and paypal fees I'm in about $475 + my original cam gears. That money could have been spent so much better on this car.

Ok so even though the cam gears have been frustrated, they aren't holding up this project at all. Still waiting on my forged pistons from race-tech. I got a call 2 weeks ago from them giving me all the bs excuses why they aren't done including they sat on the wrong desk for weeks, then had to wait to get smaller forging blanks for weeks, then they started to make them exactly like the sample pistons I sent until they realized I wanted 10:1's so they had to start over. I STILL haven't heard if they are done and I'm getting to the point where I don't even care.

Really trying to stay positive because I do want to drive this car again but I'm almost to the breaking point. All the time and money seems wasted, nobody I deal with seems to give a sh*t and this endless cold weather has my other projects backed up to the point where I'm buying different cars to avoid fixing problems I have with the old ones. Well sorry for the rant, just had to get some of that off my chest.

In light of trying to stay positive, here's what I bought in an attempt to preserve my sanity and some semblence of happiness while waiting on parts for the shadow. Got a heck of a deal on it and will probably sell it later in the summer to pay off the loan (might even make a few bucks over the loan/interest) BTW riding something like this should be on everyone's bucket list, modern crotch rockets are just mind blowing to the point that I can't believe it's legal to own one.