Unicorn II update.... - Page 2

NightHawk756 · 11-14-2006, 07:57 AM

Quote:

Originally Posted by Wall96cobra

Yeah I just need to replace some bearings in the rearend so I haven't driven it in a month. But I'm gonna do that this weekend.

Nice!!!

I can't wait to see it in person!!

Italian LX · 11-14-2006, 08:38 AM

Congratulations on getting it on the road, Brad. Now for the fun part of tuning and perfecting it.

Quote:

Originally Posted by flashbang756

We got an 18 psi spike and she blew a head gasket on #8.

Kind of suprised at that -- aren't the o-ringed heads supposd to help prevent that? I wouldnt think they would blow at that low of a boost level.

Wall96cobra · 11-14-2006, 09:20 AM

Quote:

Originally Posted by Italian LX

Congratulations on getting it on the road, Brad. Now for the fun part of tuning and perfecting it.

Kind of suprised at that -- aren't the o-ringed heads supposd to help prevent that? I wouldnt think they would blow at that low of a boost level.

I bet it was detonation, especially since he had oil in the combustion chamber.

NightHawk756 · 11-14-2006, 10:11 AM

Quote:

Originally Posted by Italian LX

Congratulations on getting it on the road, Brad.

Thanks man!!

Quote:

Kind of suprised at that -- aren't the o-ringed heads supposd to help prevent that? I wouldnt think they would blow at that low of a boost level.

Yep...they're supposed to help with that. Not sure really...exactly...what the problem was. Probably a combination of things.

I may end up selling the heads(since I really don't want to start shaving the heads to remove the o-rings) and buying another set. Then use some copper head gaskets that are made with an o-ring of sorts in the gasket itself. They are supposedly tested to 1200 hp. Decisions...decisions.

NightHawk756 · 11-14-2006, 10:19 AM

Quote:

Originally Posted by Wall96cobra

I bet it was detonation, especially since he had oil in the combustion chamber.

That's part of what I think caused it. The only thing was it blew on #8, but the oil was in #5. But, it was still in the same bank. Plus, when you start getting to that power level....pump gas begins to have it's limits...especially combined with the oil issue. We couldn't hear any detonation...but that doesn't mean anything.

Still just trying to feel everything out and get an idea. I have the heads getting looked at right now. I want to make sure that that specific head wasn't actually slightly off in the area that it blew. I did buy them used. But with a receipt from TEA with all the work that was done, including hot tanking and checking everything. But that doesn't necessarily mean anything.

QWKSNKE · 11-14-2006, 03:24 PM

All it takes is oil fumes in the cylinderto cause detonation. Oil fumes from even a PCV return setup will lower your octane rating significantly.

Brad, do you have any idea where your WOT timing was set to? Based off your 9psi #'s I am assuming you guys had very little timing in it. How did your a/f look before the head gasket blew?

NightHawk756 · 11-14-2006, 07:08 PM

Quote:

Originally Posted by QWKSNKE

All it takes is oil fumes in the cylinderto cause detonation. Oil fumes from even a PCV return setup will lower your octane rating significantly.

Yeah, I agree. As I was saying...pump gas begins to have it's limits, but when you introduce oil into the mix...then it really begins to become a major factor.

Quote:

Brad, do you have any idea where your WOT timing was set to? Based off your 9psi #'s I am assuming you guys had very little timing in it. How did your a/f look before the head gasket blew?

Lee, I really couldn't tell you what the WOT timing was at...but it was pretty conservative. Especially on the break-in tune. The reason I don't know is...Blake was doing the tuning on the SDS and I really just put it in his hands.

The air/fuel was more than fine....as a matter of fact, at the top of the rpm range, it had actually started dropping off the graph because of being so rich. And Blake was trying to atleast get it back on the graph when the gasket blew.

NightHawk756 · 12-12-2006, 06:33 AM

Well, the car's back on the road again. And, I may be wrong....I haven't driven it in about a month after the head gasket blew.....but it certainly feels much stronger.

Turns out that the pcv oil baffle on the lower intake wasn't there. I bought it used and it's apparent that one was never even installed on it. And of course, I never noticed this. Duh.

And it was definately dumping oil in atleast #5 and #8 cylinders pretty significantly. So, we've got her buttoned up now....with a baffle freshly installed on the intake

, and an oil seperator for extra insurance. I'm gonna drive it for as many miles as I can before carrying it back to the dyno. It needs a little more tuning. It has a bit of a stumble that needs to be worked out. And I'm sure the tune needs to be changed now that I don't have two weak cylinders.

I'll keep this thread updated and try and start uploading dyno sheets also once I get back to the dyno.

1sicklx · 12-12-2006, 06:48 AM

QWKSNKE · 12-12-2006, 06:57 AM

Quote:

Originally Posted by flashbang756

Well, the car's back on the road again. And, I may be wrong....I haven't driven it in about a month after the head gasket blew.....but it certainly feels much stronger.

Turns out that the pcv oil baffle on the lower intake wasn't there. I bought it used and it's apparent that one was never even installed on it. And of course, I never noticed this. Duh.

And it was definately dumping oil in atleast #5 and #8 cylinders pretty significantly. So, we've got her buttoned up now....with a baffle freshly installed on the intake

, and an oil seperator for extra insurance. I'm gonna drive it for as many miles as I can before carrying it back to the dyno. It needs a little more tuning. It has a bit of a stumble that needs to be worked out. And I'm sure the tune needs to be changed now that I don't have two weak cylinders.

I'll keep this thread updated and try and start uploading dyno sheets also once I get back to the dyno.

Where do you have your PCV valve venting too. I learned the hardway not ot vent back into the induction system. Need to run it to a catch can

12-12-2006, 06:33 AM	#18
NightHawk756 Si vis pacem, para bellum Join Date: Dec 2004 Location: Tick-Tock, Tick-Tock....... Posts: 5,146	Well, the car's back on the road again. And, I may be wrong....I haven't driven it in about a month after the head gasket blew.....but it certainly feels much stronger. Turns out that the pcv oil baffle on the lower intake wasn't there. I bought it used and it's apparent that one was never even installed on it. And of course, I never noticed this. Duh. And it was definately dumping oil in atleast #5 and #8 cylinders pretty significantly. So, we've got her buttoned up now....with a baffle freshly installed on the intake , and an oil seperator for extra insurance. I'm gonna drive it for as many miles as I can before carrying it back to the dyno. It needs a little more tuning. It has a bit of a stumble that needs to be worked out. And I'm sure the tune needs to be changed now that I don't have two weak cylinders. I'll keep this thread updated and try and start uploading dyno sheets also once I get back to the dyno. __________________ 1989 Saleen SSC 1988 AL DPS SSP

12-12-2006, 06:48 AM	#19
1sicklx BamaMafia 4 Life Join Date: Feb 2005 Location: Lake View, AL Posts: 2,577	__________________ 1999 Ford F-150 Lariat

11-14-2006, 03:24 PM	#16
QWKSNKE 3v's are slow Join Date: Dec 2004 Location: Here and There Posts: 17,152	All it takes is oil fumes in the cylinderto cause detonation. Oil fumes from even a PCV return setup will lower your octane rating significantly. Brad, do you have any idea where your WOT timing was set to? Based off your 9psi #'s I am assuming you guys had very little timing in it. How did your a/f look before the head gasket blew?