Project CADE -> T = FAILURE

Post by **NeedCAforS13** » Wed Apr 14, 2004 2:41 pm

Well, today I had yet another great CA experience! WOOOOO!!! Fair warning to anyone considering using DE pistons in their DET...

DON'T

I cracked a piston on stock boost/everything. Woo-de-fu<king ooo. Thats all for now.

I need to go hit something...

Sean

Post by **240 Trainee** » Wed Apr 14, 2004 2:41 pm

well, I'm glad dee put DET pistons in my DE.

Post by **nextlevel** » Wed Apr 14, 2004 2:41 pm

sorry to hear that man, hope everything works out

Post by **biosehnsucht** » Wed Apr 14, 2004 2:41 pm

I'm planning to get aftermarket pistons made, that'll take the abuse.. I'm going for 84mm and probably 9.5:1 myself, it's probably just the stock DE pistons are weaker than DET.

Someone mentioned on here they even looked weaker, but those were FWD DE vs RWD DET, so dunno if RWD DE is the same.

Post by **gani** » Wed Apr 14, 2004 2:41 pm

if i was to go higher compresion id go max 9.0:1 jsut so that i still ahve a safety coz when you are tuning you will ahve to richen up you feul maps thus loosing some hp just so that you dont detonate. as for me im all about lowerring the comp get that bad boy to like 8.0:1 or even 7.8:1 then boost the crap out of it thats why you got the arp head studs right!!!!

Post by **NeedCAforS13** » Wed Apr 14, 2004 2:41 pm

it wasn't detonating at all... dee drove it for about an hour this weekend and gave it a thourough beating. it was the fact that timing was set at 15:(

and to top it all off, I had the car towed home, and when it got here, the truck's hydrolics died, so they had to take it to their shop and I couldn't get my car off it:( this blows a$$

Sean

Post by **240 Trainee** » Wed Apr 14, 2004 2:41 pm

Yea, that seriously sucks man. I hope you get this resolved.

Post by **Trigger** » Wed Apr 14, 2004 2:41 pm

sorry to hear this sean. let us know whats going on

Tim

Post by **crzycav86** » Wed Apr 14, 2004 2:41 pm

I'm just wondering... wouldn't the knock sensor do something about that 15 deg. timing? Wouldn't it be able to retard timing until the knocking stopped?

Post by **NeedCAforS13** » Wed Apr 14, 2004 2:41 pm

it wasn't knocking. at all. i have stock exhaust so you can hear everything... dee listened for himself!

but he did say, now that he can look back (gotta love hindsight) that he felt the ECU trying to retard the timing at top end (like the car would go like hell till it hit like 30 advance then the ECU would back off like crazy and the car would kinda level off and stop accelerating)...

Sean

Post by **NeedCAforS13** » Wed Apr 14, 2004 2:41 pm

oh it was at stock DET timing of 15btc just like the FSM, but apparently the timing maps are for a different piston, so I should have modified it accordingly and backed off timing to 10 or so:( can't do what you don't know I guess...

Sean

Post by **Nismo1182** » Wed Apr 14, 2004 2:41 pm

Damn Sean, looks like you and I are both out for a while. Mikes been the only one with out problems, that we know off.

Post by **GotBoost4Yall** » Wed Apr 14, 2004 2:41 pm

How many times are you going to tear the motor apart???

Seems like these CAs can be real POS, or just abused to hell. Makes me not ever want to mod this motor at all.

Anyway I'm most likely movin out so its either getting sold or traded torwards a 98 s14 and keep it stock and clean.

Too much money being blown away

Post by **Nismo1182** » Wed Apr 14, 2004 2:41 pm

Im getting tired of fixing it and having it break again. This time it wasnt even my fault. Dont know what to do yet.

Post by **boost_boy** » Wed Apr 14, 2004 2:41 pm

Unfortunately folks, this is a learning curve. Hell, it's not my car, but I feel partially responsible because I drove the car and knew something was missing. It had enough torque to get you off the line like an SR, but turned into a nice sissy-boy engine in the higher RPM. And because the car drove so damn nice and quiet, I didn't fret. Didn't bother to probe further by asking him what was the timing set at; though I showed interest by maing him check his compression in my presence and checking out his plugs. Even drove Kevin's car and that thing was knocking and smoking.

On Ben's engine (240 Trainee), I was tempted to try it, but I was in no position to experiment on someone else's motor. And besides that, I put my heart into his frickin' motor. It should be perfect!

Fortunately, they are repairable and the CA18 is not a POS. One way or another, we all get our turns of failure. I've took out 3 motors already just to learn what's good and bad for the CA18DET. Unlike it's predecessor the SR20DET, the CA18DET just like the RB and VG series is not that big on advanced timing.

He'll be alright soon! I only stay 3 hours away........

Dee

Post by **Nismo1182** » Wed Apr 14, 2004 2:41 pm

I cant afford to keep fixing it. Everything is cool for a few months then something breaks again. As of now, I'll be hitching rides from people, like I did with you on sat.

Once I fix it, theres a strong chance it might go for sale. It was fun while it lasted. Thanks a lot for your help with it, Dee. And everyone else on the forum also. I'll still be around to add my 2 cents on things.

Post by **gani** » Wed Apr 14, 2004 2:41 pm

thats why i got 1 extra block in my garage.

Post by **biosehnsucht** » Wed Apr 14, 2004 2:41 pm

Aha that makes sense.. different length spark plugs affect timing advance as well, so different shape pistons should too.

Since the top of the piston is in a different place relative to the spark when its shaped different..

Some nice complicated maths can probably figure the difference in effective timing but the mere thought of it makes my head hurt.

Measure the difference in highest points and figure out how much retard you have to give it to make the spark start at the same place, I would guess... or just get some forgies, but still be careful of the timing. If anyone has a stock CA18DE RWD ECU might be worth pulling the timing map off of and comparing.

Post by **Jezz_s13** » Wed Apr 14, 2004 2:41 pm

Increasing CR seems a bit odd.

No one increases and most reduce to ~8:1 in the UK on the CA.

Post by **float_6969** » Wed Apr 14, 2004 2:41 pm

There IS reasoning behind increasing the compression. Ok, so here is the deal;

When turboing a motor, most people lower the compression so that you can run more boost. But the problem is that you sacrifice your bottom end when you do that. Kinda like putting a great big turbo and lumpy cams in a car. It's great in the top end, but doesn't have a nice powerband. It's too peaky. BUT if you aren't nessiccarily looking for max power, and you want a broad powerband, you can run less boost, but raise the compression so that in the lower end you've got the compression to give you power before the turbo spools, and then the turbo will carry you the rest of the way through. The problem is that it puts a lot of stress on the head, gasket, piston, rods, bearings, and crank. I still intend to build I high compression CA motor to autocross with, but I'm going to learn from Sean's mistake and wait to put in forged high comp piston's and some sort of standalone engine management so that I can have better control of the timing. We're all (Or should be) aware of the CA's dislike for advanced timing. Unfortunatly, retarding the static timing only makes the motor safer. When you retard it for the top end, you loose out in the bottom end, which negates the whole purpose of building a high comp turbo motor anyway. Ideally you would want to set up your timing curves so that your timing would be well advanced before the turbo spooled, and then as it spooled up, the timing would retard.

Sean, I feel for ya man. But don't give up on us. One of us will conquer the high comp CA yet, just watch! Keep us updated.

Post by **CA18Fastback** » Wed Apr 14, 2004 2:41 pm

that sucks sean. just look out for a set of DET pistons and you should be good to go. don't give up hope, cuz you gotta drive out here to cruise with me and matt in may, remember?

Good luck-Ian

Post by **boost_boy** » Wed Apr 14, 2004 2:41 pm

Quote »When turboing a motor, most people lower the compression so that you can run more boost. But the problem is that you sacrifice your bottom end when you do that. Kinda like putting a great big turbo and lumpy cams in a car. It's great in the top end, but doesn't have a nice powerband. It's too peaky. BUT if you aren't nessiccarily looking for max power, and you want a broad powerband, you can run less boost, but raise the compression so that in the lower end you've got the compression to give you power before the turbo spools, and then the turbo will carry you the rest of the way through. The problem is that it puts a lot of stress on the head, gasket, piston, rods, bearings, and crank. I still intend to build I high compression CA motor to autocross with, but I'm going to learn from Sean's mistake and wait to put in forged high comp piston's and some sort of standalone engine management so that I can have better control of the timing. We're all (Or should be) aware of the CA's dislike for advanced timing. Unfortunatly, retarding the static timing only makes the motor safer. When you retard it for the top end, you loose out in the bottom end, which negates the whole purpose of building a high comp turbo motor anyway. Ideally you would want to set up your timing curves so that your timing would be well advanced before the turbo spooled, and then as it spooled up, the timing would retard.[/quote] This can actually be done, but you will need a standalone because of the multiple retard points you will need to set your engine at. The biggest things is understanding the characteristics of your engine "period". In Sean's case or anyone who wants to run DE pistons with turbo, your new base idle setting must be set at 10 degrees BTDC in order to compensate for the new piston height which is now consuming more of the combustion chamber. Note the CA18's combustion chamber is well in-line with the RB and VG series and those are know for blasting pistons via detonation. Quench design has it good and bad points.

Dee

Post by **NeedCAforS13** » Wed Apr 14, 2004 2:41 pm

CA18Fastback wrote:that sucks sean. just look out for a set of DET pistons and you should be good to go. don't give up hope, cuz you gotta drive out here to cruise with me and matt in may, remember?

Good luck-Ian

I'll be in an F350 super crew dually with about 20 crew shells behind it :pface not my car... I'm coming up to Philly for the Stotesbury Cup Regatta with my high school crew team I used to row for (and my girlfriend now coaches for them):)

Sean

Post by **float_6969** » Wed Apr 14, 2004 2:41 pm

Dee, in your opinion, do you think that if Sean had run his base timing at 10 instead of the stock 15, he would have blasted the piston, or are the stock DE pistons just too weak?

Post by **NeedCAforS13** » Wed Apr 14, 2004 2:41 pm

I think Dee said with 10 I would have been fine

Sean

Post by **biosehnsucht** » Wed Apr 14, 2004 2:41 pm

You can adjust via ECU tune the ign timing per RPM but don't think you can per boost..

Post by **r34 gtr** » Wed Apr 14, 2004 2:41 pm

damn, that sucks. im sorry to hear that happen. i hope it all works out for you. dont give up because of something like this. think of it as an opportunity to do something drastic to it. ill let you know if i find any de or det pistons for ya. good luck.

- tim

Post by **NeedCAforS13** » Wed Apr 14, 2004 2:41 pm

I don't know if you were around, but thats what I said after I blew up the first one...

http://www.nissaninfiniticlub....ibero

I just don't have any CA luck. Oh well, I still have one more motor to blow up to be even with Paul or Ray:(

Sean

Post by **r34 gtr** » Wed Apr 14, 2004 2:41 pm

yeah, true. my CA luck is horrible, it always takes a dump on me right when i start to trust it. i just think of it as a war, and by not fixing it i would be losing. its fun though, keeps me on my toes. this engine could explode and destroy my car but i would still be glad i got it.

- tim

Post by **float_6969** » Wed Apr 14, 2004 2:41 pm

I think apex/hks made a piggy back that would tune timing also. It's still RPM based though...

Project CADE -> T = FAILURE

Project CADE -> T = FAILURE

Nissan Forums

Infiniti Forums

Datsun Forums

Technical Forums

Classifieds / Marketplace

Nissan Motorsports

General Forums