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NightHawk756
11-13-2006, 10:35 AM
Well, she's running.

Basic break-in tune, pretty conservative was 411hp/428tq at 9psi/pump gas.

Went back after break-in and made another baseline. It was 438/461 at 9psi/pump gas.

We started turning the boost up a little. At 12 psi, it went to 492/615-pump gas. But, we started getting pig rich up top and Blake was tuning less fuel in. We got an 18 psi spike and she blew a head gasket on #8.

I'm glad it blew actually. Come to find out, the exhaust valve guide on #5 was dumping oil in the cylinder. So, very possibly, I had a weak chamber on #5 as a result. So, at the moment, the heads are getting clened up and new valve guides installed.

Hopefully an increase in hp numbers will follow at the same boost levels once I'm not interupting the combustion process by dumping oil in #5. :D

I'll try and update again when she's back up. We plan to go much higher with the boost level ;) But, there's just so much that little 60-1 can do. It's falling off pretty good at the end.

Whenever I get my sick computer back, I'll post up dyno graphs.

Wall96cobra
11-13-2006, 11:06 AM
Cool Brad! I was wondering where you have been. I'm sure it will be a monster after you get the bugs worked out.

NightHawk756
11-13-2006, 11:56 AM
Cool Brad! I was wondering where you have been. I'm sure it will be a monster after you get the bugs worked out.

Yeah, there's some minor things.....but she's almost right! :D

You still enjoying your bird, man??

EZ SPEED
11-13-2006, 12:19 PM
Nice!! :chug:

coupe
11-13-2006, 01:01 PM
Way to go. It's more than enough for a street car. :chug:

NightHawk756
11-13-2006, 01:07 PM
Way to go. It's more than enough for a street car. :chug:

Yeah, but there's plenty more left in her. :D

QWKSNKE
11-13-2006, 01:43 PM
niiiiice

rtusnake
11-13-2006, 03:16 PM
Sweet, all your cars turn out awesome. Post some pics up to

NightHawk756
11-14-2006, 07:01 AM
Sweet, all your cars turn out awesome. Post some pics up to

I'll make sure to do that......I actually didn't take any new pics once it got running. I was too busy enjoying it I guess. :doh:

I actually drove it to a show in Chattanooga and it won "Best Engine". I don't even have any pics from that show either. I just dropped the ball I guess. :nono:

Wall96cobra
11-14-2006, 07:33 AM
Yeah, there's some minor things.....but she's almost right! :D

You still enjoying your bird, man??




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.

NightHawk756
11-14-2006, 07:57 AM
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!!! :nice:

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

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. :nice:

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. :shrug:

Wall96cobra
11-14-2006, 09:20 AM
Congratulations on getting it on the road, Brad. Now for the fun part of tuning and perfecting it. :nice:


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. :shrug:



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

NightHawk756
11-14-2006, 10:11 AM
Congratulations on getting it on the road, Brad. Thanks man!! ;)

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. :shrug: 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
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
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.

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. :D

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
:nice:

QWKSNKE
12-12-2006, 06:57 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. :D

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

NightHawk756
12-12-2006, 11:20 AM
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

It's actually routed back in. No problems yet....the seperatorjust has to be emptied occasionally.

QWKSNKE
12-12-2006, 04:41 PM
It's actually routed back in. No problems yet....the seperatorjust has to be emptied occasionally.


Just an FYI, oil fumes are just as bad at lowering octane in the combustion chamber as actual oil is.

Ask me how I know :shake:

NightHawk756
12-12-2006, 05:21 PM
Just an FYI, oil fumes are just as bad at lowering octane in the combustion chamber as actual oil is.

Ask me how I know :shake:

Roger that!

Yeah, it seems that it's just barely any oil and mostly water from condensation that ends up in the seperator. But any oil is still worse than none. I'll have to keep in mind that I may have to eventually go the route you did with a catch can.

QWKSNKE
12-12-2006, 08:10 PM
Roger that!

Yeah, it seems that it's just barely any oil and mostly water from condensation that ends up in the seperator. But any oil is still worse than none. I'll have to keep in mind that I may have to eventually go the route you did with a catch can.

normal driving and a little boost will be 'ok' but don't hammer on it a whole lot until picking up a catch can.

I shot the #3 fire ring out from underneath the head earlier this year because of detonation from oil fumes coming into the induction

NightHawk756
12-12-2006, 09:18 PM
I think my o-ringed heads helped a good bit. I put about 800 miles on the car after about 5 dyno pulls. And those miles weren't all just babying it. And then it made about 12 dyno runs all while increasing boost before the gasket blew on #8. And that was before the intake baffle/seperator was added.

Do you have any other type of crankcase evac like a valve cover breather or anything???

QWKSNKE
12-13-2006, 05:05 AM
I think my o-ringed heads helped a good bit. I put about 800 miles on the car after about 5 dyno pulls. And those miles weren't all just babying it. And then it made about 12 dyno runs all while increasing boost before the gasket blew on #8. And that was before the intake baffle/seperator was added.

Do you have any other type of crankcase evac like a valve cover breather or anything???

yeah. LH valve cover has a breather and I had another PCV on the RH valve cover.

-but-
Going to the standard tension rings (the only reason I tore the engine down a month or so ago) has helped my problem tremendously. Paul had ordered me low tension rings originally and I didn't know it until it was to late

NightHawk756
12-13-2006, 05:51 AM
yeah. LH valve cover has a breather and I had another PCV on the RH valve cover.

-but-
Going to the standard tension rings (the only reason I tore the engine down a month or so ago) has helped my problem tremendously. Paul had ordered me low tension rings originally and I didn't know it until it was to late

Ahh ok.

I wonder if he knew he ordered those or if that's just what his distributor sent and he didn't know it? Makes me wonder what rings I have.

How do you know? Does it have an affect on combustion? Or excessive blow-by or something?

QWKSNKE
12-13-2006, 07:12 AM
Ahh ok.

I wonder if he knew he ordered those or if that's just what his distributor sent and he didn't know it? Makes me wonder what rings I have.

How do you know? Does it have an affect on combustion? Or excessive blow-by or something?

my machinist noticed it when reviewing the part number when the engine was being built. Also, that is when my car started having boost issues. Since they were low tension, the boost was collapsing the rings and going past the rings causing excessive pressure in the crankcase. This in turn was forcing more oil and oil fumes out the PCV system and going into the intake track. I killed 3 sets of head gaskets due to this over the course of a year. Unfortunately it took me over a year to figure this out.

NightHawk756
04-07-2007, 08:50 AM
Update:

Carried the car back to the dyno for some more minor tuning. It made 482/526 at 10lbs. Which is right at what it was making at 15lbs. with the oiling problem. And that's with pretty conservative timing/fuel for the moment.

Here soon I'll be installing a 3 bar map and turning the boost up.

Lee: I'm now using an evac system like we were talking about. No canister yet, just a filter on the end of the evac line for the moment. This in conjunction with the oil seperator that was already installed. Thanks for the advise! ;)

QWKSNKE
04-07-2007, 09:16 AM
Update:

Carried the car back to the dyno for some more minor tuning. It made 482/526 at 10lbs. Which is right at what it was making at 15lbs. with the oiling problem.

Here soon I'll be installing a 3 bar map and turning the boost up.

Lee: I'm now using an evac system like we were talking about. No canister yet, just a filter on the end of the evac line for the moment. This in conjunction with the oil seperator that was already installed. Thanks for the advise! ;)

No problem. Hope that clears any potiential issues up.