Some of you may know that I was almost finished with my build. Well, it was time to tune today and I was supposed to get my car back, but I have a MAJOR issue of some sort that I just can't figure out (as of now). I have the following things that just went into my build:

Wiseco Forged Pistons 8.8:1 CR (.020 over with ceramic coating on shirts and tops)
Eagle Forged Rods
ARP Rod Bolts
ARP Head and Main Studs
Cometic/Cosworth Head Gaskets
Darton Sleeves
Block oil passages cleaned
Block redecked
Block Bored and Honed using a Torque Plate
Crank balanced
Crank journals polished
New Rod and Main bearings
JWT S1 Upgraded Cams
JWT Heavy Duty Valve Springs
Heads oil passages cleaned
Heads redecked
Ported exhaust and intake runners
5 angle valve job
Valve Stem Heights set
Cold Clearance set
New Valve stem seals
New OEM Nissan Oil Pump

Crawford Plenum, ATS triple carbon clutch, ATS carbon LSD, Koyo radiator, Nismo thermostat, Greddy Radiator Breather Tank, AAM Fuel Return, 750cc injectors, Utec, eo-1 boost controller, dual 3 inch exhaust with wastegate dumps, DSS 1/2 axles.

Was getting tuned at 12.5 psi and 16.5 psi and I was expecting around 500-525 on the 12.5 map and around 600-625 on the 16.5 map. NOT EVEN CLOSE THe car is putting down somewhere around 350 rwhp at 12.5 psi and around 430 rwhp at 16.5 psi. Needless to say that I feel

A/f ratio is all good across the board, they checked for boost/vacume leaks and none were found. Power falls off hard after like 5000 rpm or so. When I left they were going to try to do a compression test on the engine to see what that showed. Hopefully I hear something tonight because again I feel

I spoke to Kyle at IPP and Todd at builtZmotors and they were helpful in trouble shooting. Again, thanks Kyle and Todd.

The more I think about it, I think that it may be an issue with the cam timing chain being off by 1 or 2 teeth which would be having the intake and exhaust valves opening/closing at all the wrong times and thus loosing major power. My car has been throwing a lot of random misfire codes too (I know this code is common, but it has been throwing the code a lot and at times the SES light flashes on and off). Does anyone have any ideas what's going on with my car? I'd really appreciate all input that could lead to the resolution to my issue so I can get my poor Z out on the road where it belongs. Thanks guys.

 

that sucks i hope u get it all fixed and running good

 

Just heard that the shop doesn't have time to do any tests on it today What a horrible feeling.

 

Oh man that is the worst feeling, after you spend all that money to get the same power as a stock engine, something as to be wrong, who is doing the tunning? I am very curious to see what happens

 

[QUOTE=Yancy]

The more I think about it, I think that it may be an issue with the cam timing chain being off by 1 or 2 teeth which would be having the intake and exhaust valves opening/closing at all the wrong times and thus loosing major power. My car has been throwing a lot of random misfire codes too (I know this code is common, but it has been throwing the code a lot and at times the SES light flashes on and off). [QUOTE]

this would be difficult to do, did you have an experienced builder time the motor? the timing chain is color coded and there are several precautions and checks that would prevent this...if your cams are off, this could result in power issues for sure....

why do you think this? any reason besides the codes? what codes?

good luck, sorry I couldn't be of any more help on the phone

-TODD

 

how much did you spend for all those parts plus labor?
that really sucks.

 

lets just say, a lot

 

Can't help you Yancy but I've got to say Todd/builtZmotors is a heck of guy for trying to help you out! To be able to call a builder/tuner for advice on a motor they didn't even build is a real testament to the kind of business he's running. If that doesn't confirm he's the kind of sponsor we should buy from, I don't know what would.

 

Sucks to hear that man, hope you get some news soon.

 

Could the cam sprockets be installed backwards? I remeber another member had a similar problem and they had to flip them around. I think it was something like that. Can someone who knows more about this chime in maybe Todd? Hope you find the problem.

 

Very very true. Todd is an awesome guy for taking the time to help me out on an engine he didn't build. I would encourage people that are considering engine builds to consider Todd. Kyle at IPP was also a big help to me too. The guys at the local shop are the ones that installed the timing chain and gears and I think they may have put the cam gears on the wrong sides by accident.

 

This is exactly what I think the issue is. I read a post from Overzealous from about 6 or so months ago where it looked like he had a silimar issue with his engine. His car was running like crap and it kept throwing p0300 codes and the SES light was blinking on and off. It turned out that his cam gears where accidently installed on the wrong side from where they needed to be (left on the right and right on the left). Apparently, the cam gears look very very similar and fit on both sides, but it means the world if they are installed on the wrong sides of the engine. Thankfully, he did not see any damage to the valves which did not make contact to the pistons.

As we all know, my car is down on power by about 200 rwhp at both map settings. My car is also continuously throwing the P0300 (random misfire code - not the typical once and a while throwing of the code but every time the car is started and ran). The SES light in my car is also flashing on and off quite a bit. These appear to be the same symptoms that Overzealous had when his cam gears were on the wrong sides. In a world of bad things that could be the issue, I'm actually hoping that this is what is wrong with my car. I'd like to have the shop here in Michigan pull the front cover, check the timing chain to see if the teeth are all lined up and then flip the cam gears from the sides they are currently installed to see if that is the issue.

 

[QUOTE=350zDCalb][QUOTE=Yancy]

The more I think about it, I think that it may be an issue with the cam timing chain being off by 1 or 2 teeth which would be having the intake and exhaust valves opening/closing at all the wrong times and thus loosing major power. My car has been throwing a lot of random misfire codes too (I know this code is common, but it has been throwing the code a lot and at times the SES light flashes on and off). Todd, thanks again for talking with me to help me diagnose the issue. As Brian from Ohio said, that says a lot about the business you are running to take the time to talk to me about my problem and try to help.

After further research for similar problems that have happened in the past, I came upon a post from Overzelaous (Scott from SVRTech) that was having very similar issues about 6 months or so ago. After reading his post, I now believe that my cam gears are on the wrong sides. The shop here in Michigan that installed the cam gears and timing chain may have accidentally installed the gears on the wrong sides because the gears apparently look almost identicle and fit on both sides. I consider Scott (Overzealous) a pretty knowledgeable guy and he made this mistake when doing this himself on his own engine. I think of the possibilities, this may be one that could take a day to resolve if it turns out to be the issue because the shop hear could pull the front cover, check the timing chain just in case, then swap the cam gears from one side to the other. Here's a link to Scott's (Overzealous) past post reagarding his issues with the cam gears (see post 1, 12 & 19).

https://my350z.com/forum/showthread....m+timing+gears

What do you think? Could this be what's wrong with my car?

 

I have talked to a few people this morning, at our shop and Sharif as well... The timing chain could be off a few teeth, this would definately have a similar effect..I don't have a sprocket in front of me to piece this together, so i can't comment on this with any level of certaintly...

Yancy: Sharif said he won't be online for a while- he just moved..call him on his cell:
626-485-2100

SIDE NOTE: this is one of the major reasons that we sell our longblocks timed...to prevent these mishaps!

-TODD

 

well to further get into this, i have now called nissan trying to get part numbers for the left and right bank intake cam gears. guess what, nissan only has one part # and the parts guy says they can be used on either side!! confusing huh? it is SUPER important to mark ALL your cam gear placements, valve bucket placement, and cam saddle palcement upon disassembly. i had to build a VQ35 last week where the guy who tore the motor apart did not mark anything!! it was a reputable shop also that definately should have known better!! i had to look super close at the wear marks on the back side of the cam gears and match the seating marks to the correct sides.
so yes the intake cam gears look and are indexed identically, and nissan can't even help ya with part numbers to get them back on right.
yancy, one of the easiest ways to tell if this happened is to read your 02 sensor readings. bank 1 (pass. side) should be running very lean, with bank 2 running very rich. also, my part throttle was junk and would always toss the po300 code. when i got past 3000rpm, the thing went like a raped ape though and felt great.

hope ya get it figured out.

 

Man that blows Shawn... if it makes you feel better... mine when on after you and was supposed to be finished... they left the UTEC sitting on the floor and nothing bolted back in...

but the car did make 505whp at 15psi... gonna stick with that tune cuz it seems to be running really nice... and just wants to be a drift car on 275's

Sorry again bro! Wheel to Wheel offered to help me out next time if there were any BIG issues with my Z ... They said they have a VERY fast reaction time and build time on all their cars! They are in michigan too BTW... good people my dad is friends with the guys... HUGE frigin shop too they build funny cars and well known drag cars

 

Well the Nissan parts manual for the 03 anyway shows the chains and gears being the same parts numbers. On the file below you see two each for the gears and chain and th eonly thing different are the four cams

 

Yup, cam gears are definately the same part number left and right, so that couldn't be an issue. I always mark them anyways, as its a good habit to get into. Incorrect timing chain position is certainly a possibility, but I would confirm the engine health via comp/leadown test...prior to messing with the chain.

These type of puzzles are always frustrating. As I mentioned on the phone, the shop will need to step through a process of elimination.

I am here to help if I can!

 

Hey Sharif,
Thanks again for taking time on a Sunday to talk to me about my issue. I really appreciate it. It shows that you, and Todd as well, are great sponsors for the site and just all around great guys to try to help a brother out. I'm going to have them do a comp test, leak down test, check plugs and coil packs, then the timing chain and then go from there. I spoke to a guy that was there when my car was on the dyno - the smoke blowing out the exhaust was positively black smoke. Could it be the exhaust valves opening when way early and drawing the fuel out the exhaust? Thanks again.

 

Possibly. Without having an AF gauge on each bank, it would be hard to tell. You mentioned the AF ratios looked normal on the dyno, so the black smoke could have come from a rich bank, and if the AF probe was mounted on the other side, your AF ratios would look normal. And because Scott's exhuast system has an x-pipe, you would have smoke coming out both pipes. Makes trouble shooting even more challenging.

Let us know how it goes.