my turbo KA sucks right now

[klattr1]

have a 95 240sx fully built(JE oversized pistons 8.5:1 and Crower rods, Cometic headgasket and Jim Wolf cams. I run a setup very similar to Chris Mays.(72lb injectors, Cobra Mafs, Jim Wolf ecu)Well i hooked up the boost controller today and turned it up to 10 and then to 14 psi. No problems, No detonation, Fast as hell!But around 6:00 I boosted in 3rd gear all the way to 14(not past 14 at all) and then I heard sounds of detonation(marbles in a jar sound) and then I let off the throttle. Well I pulled off into a grocery store parking lot a half a mile down the street where i boosted and I noticed a severe loss of power(like running on 2 cylinder).I pulled the spark plugs out and the first and fourth cylinder spark plugs had no gap whatsoever. The arch was slammed against the electrode or point whatever you call it. NO GAP and charcoal burnt on 1st and 4th.I was like Oh SH(T. So my Dad brought his compression gauge and sure enough, 1st and 4th cylinders had 0 psi and the 2nd and 3rd had 110 psi(low compression motor).I looked at the tops of the pistons and no visible damage was done. What are yall's experiences with this?I will be pulling the head tomorrow to check out everything?Possible valves or piston rings?Obviously there was not enough fuel to support that boost level. So If i get it fixed right, I will have to check for stock fuel pressure regulator function and 300zx TT fuel pump function. I will prolly buy a new fuel pump.Help me out as much as possible with advice or personal experiences.14 psi felt good but only for 30 min.Thanks,RyanHere's my webpage with a list of parts and modificationsWebsite KA-T

[95_240sx]

Oh my...let me be the first to tell you im really sorry to hear about it! It doesnt sound too good, be sure to let me know if you need spare KA parts, I have a couple lying around now

Rick

[C-Kwik]

Use a leakdown tester. You'll hear air where it is coming from. Out the intake if the intake valves are shot. Out of the exhaust if the exhaust valves crapped out. Out of the crankcase tube if the rings or pistons are toast. And out of the radiator if the headgasket is blown.

[klattr1]

Use a leakdown tester. You'll hear air where it is coming from. Out the intake if the intake valves are shot. Out of the exhaust if the exhaust valves crapped out. Out of the crankcase tube if the rings or pistons are toast. And out of the radiator if the headgasket is blown.

where do i get a leakdown tester? Autozone? or is the a dealership/mechanic special tool?

[klattr1]

Oh my...let me be the first to tell you im really sorry to hear about it! It doesnt sound too good, be sure to let me know if you need spare KA parts, I have a couple lying around now

Rick

luckily i have another block laying around just in case i need to have machining done in the bottom end or such. Once I pull the head off i will be able to tell alot.Thanks for the offer, I'll keep you informed in the future!ThanksRyan

[:: orion ::]

CHECK YOUR BASE TIMING...

I just did the 3rd HG on a built KA b/c (unbeknownst to us - !st time I had wrenched on the car) his base timing was at 27 BTDC instead of 18-19 where it should have been for ~20psi from a T04B, supported by JWT and 72lb'ers...

Detonation = blown HG on a built motor...it's the fuse. But with a Cometic...??? Who knows what took the brunt. I'd use an OEM gasket next time - They can hold up to ~30psi, and if there is a problem, you blow it rather than breaking other more expensive parts.

Anyway, sorry to hear about it...

Later - Brian

[DaveEEE]

You said "110psi on 2 & 3 (low compression)" as if its good....... you should still be around 150psi on those cylinders bub.

[Nathan]

That really sucks, I hope it's something simple but it sounds kinda nasty...

[C-Kwik]

where do i get a leakdown tester? Autozone? or is the a dealership/mechanic special tool?

Do a search on the internet. That's how I found mine. Do some looking around and you should be able to find one under $100. Mine is made by Tavia and it works quite well. Auto parts stores don't seem to have them. I found most hits with race shops. Particularly with the ones that work on V-8's. I got mine from one that specializes in alcohol fueled funny cars.

You will also need access to an air compressor though. And it does require a bit more work to use as you will need to turn the crank by hand to the position you want to test at. But now that I think about it, you can probably get away with just buying the hose that screws into the spark plug hole as it uses a standard quick connect air hose connection. At least for the purposes of just listening for where air is coming from. But While you are at it, I'd opt to get the whole thing.

[klattr1]

I pressure tested my engine. Cylinder 1 leaks to cylinder 2. Cylinder 4 leaks to cylinder 3. Tests were performed with pressurizing regulator and all valves closed on cylinders tested. No air going into radiator - no air from oil dipstick tube - just leaks between cylinders. Funny thing is the standard pressure test on 2 & 3 read 110 and cylinders 1 & 4 read 0! Any ideas.

[Projex240]

Ryan, where are you doing this at? Are you in town(cola)? I didnt make it to nopi, so if you are in town, give me a call, so we can get up and see if we can figure it out.

[95_240sx]

I am still stumped as to what would have run into your plugs unless it was a piece of debris and the HG was coincidence.

What plugs are you running?

Rick

[andrave]

if he blew a headgasket couldn't some of the headgasket have been ingested and tossed into the spark plug? unlikely.....

[95_240sx]

Possible, but not unless he completey demolished the head gasket.

Rick

[andrave]

any news on this one, klattr?

[klattr1]

the car is parked right now at my house. I left it there because I have worked on it too much in the past 2 month and i need to concentrate on school also. I had to get away from it since it pissed me off. I ended up visiting some friends and playing around not messin with the car.The head will be pulled off sometime this week. I hope that its only just the headgasket and nothing else. It should be up and running next weekend if the surface of the block is fine. After that I plan on going directly to the dyno to make sure before I turn up the boost too far. Timing will be checked first. Its just wierd that at 5 psi it ran strong and fine but at 14-15 psi range it detonated that once.I might send out my fuel pump to be flow tested also.(300zx TT fuel pump). I know ill never buy a used fuel pump again though just because it has thrown variables into the equation now.If all it took was one sound of detonation to blow the headgasket, how will i know it wont mess it up on the dyno if i start to turn up the boost. If i hear it once on the dyno, does that mean the headgasket is gone again or do i just turn it down from there?Plugs are whatever Jim Wolf recommends. I think its PFGR-11Something close to that

[andrave]

should NORMALLY be able to hear a little detonation before you break stuff, especially with 8.5:1 cr...no clue though, yours seems like a freak accident.

[klattr1]

HEY KLATTR1:Not to change the subject here, but where did you get that shield wrap for your turbine..?? I need something like that...And, sorry to hear about your motor...

Thats why i keep my ka-t at 9 psi... dont want all these other high boost ka-t problems..!!

i got the turbine heat shield from ATPwrap.com. His name is Tim.It was expensive but its 3000 degree resistant.I think the distributor of their inconel heat shields is twinsturbo.comCall up either one and tell them what turbine you have and what ar ratio and they will either custom make it for your kind or they might have it in stock.

[kumanchu]

any of you ka24de-t people still have your old injectors? i need one

[klattr1]

I took my motor out in 4-5 hrs today and it will be going to the machine shop on Monday for inspection and then im gonna have him fix it if anything is messed up.Ill will report back when i find out what's wrong with it.

[95_240sx]

Hope it turns out being something simple.

And if its any consolation, my car is broke at the moment

Rick

[Nathan]

If it's any consolation I've never even driven my car

[klattr1]

thanks guys,it seems like me and a lot of my friends have broken cars right now. It always happens when i rush stuff. I wanted to turn the boost up even though i have not been to the dyno yet. Oh well, Shat happens!What i plan on doing differently is to have a aftermarket fuel pressure regulator with a gauge so i can make sure base fuel pressure is at 43.5 psi and that it performs correctly under boost.The first thing to do after break in will be dyno time so i can turn up the boost safely and monitor stuff at the same time.Maybe an Aeromotive fpr or something.

[Structure240sx]

cylinder 3 and 4 on my car are shot right now. i think i have like 60psi in 3 and 110 in 4. ill be dropping a built engine this week tho hopefully. good luck to u i was in the same spot u were last week

[95_240sx]

What front bumper is that Structure?

And holy cripes, I need a CF drunk lid too, whered u get that?

Rick

[klattr1]

update on the motor.Ring lands are cracked on all 4 JE oversized forged pistons.It sucks real bad. The head might be damaged too. But I have another KA motor sitting around to put in so thank God i'm not out of a car for too long.The only thing is that this other motor has 100,000 miles on it and I won't run it higher than 11 or so. But on the stock compression ratio it should make plenty of power.I can buy about 3 stock KA's (junkyard) for the price that it would cost for the low compression motor to be rebuilt with new forged pistons and rings and other machining.We'll see what happens now!

[JJ240]

You should get in touch with JE about that. You may be able to get some new pistons if youre lucky. Ringlands shouldnt blow that easy. (just dont make sure it sounds like they blew easy)

[WDRacing]

I'm willing to bet it wasn't the pistons. The fact that your plug gapped was slammed shut really bothhers me. The only time I've seen that was when the piston cam on contact with the head. But you were running fine before hand, so your timing was correct. I've blown a few mtors do to over boost, all of which I either cracked the ring lands or welded the rings to the pistons.

You really need to invest in a knock meter. I have one from MSD, it has saved my life quite a few times. It will detect even the smallest amount of knock.

You definitly have somthing wrong with your Ignition/AF. 72lb injectors with the correct mapping and forged internals should never blow at 15 psi. NEVER....A failing fuel pump could cause a problem, but they usually just quite. If it was on the way out, the car would shudder. Not just under boost.

WD

[andrave]

yeah it all seems odd to me too but I honestly don't know what to make of it... and the fact that it got the ring lands in all four cylinders signals to me that something is up too... Out of curiosity what brand rings are you using? The only thing I can think of that would be consistant with all the information presented except the spark plugs is that your fuel pump wasn't supplying adequate pressure to support the larger injectors at 14psi and you suffered some kind of incredible lack of fueling, which leaned out all four cyl's and pooped the motor.

But that still doesn't explain the issue with the spark plugs, which I think is weird.

[fiznat]

dont you have an A/F gauge? did you see it drop or...?