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little update

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So, I haven't been on here in a while. Lots been going on in life and with the car. In the last 5 months I went to the dyno, then went to the track and blew both head gaskets on the second run ([email protected] btw) and had to be towed home. I did a major engine overhaul, and in the middle of that I had to move AND go through a settlement for an old work injury. Yeah, I was really busy. So anyway...

Here's the down low on the engine overhaul. Both head gaskets blew on the middle cylinders (3&4) into the lifter valley. Had coolant pouring out the exhaust, in the oil pan, up in the heads, through the PCV lines into the intake and through the supercharger and the intake manifolds. It was a mess.


During the tear down process I also found a pushrod with the ball worn down to a cone right into the lifter cup! Also found wear on the roller faces of the lifters. Then I found piston #2 wasn't coming up to proper deck height :D so the entire engine had to come out and go to Engine Lab of Tampa for a tear down and inspection. Ended up being a bent rod. I took the front cover off before I sent it in and took the cam out, and also found the cam bearings where shot, as well as my oil pump drive gear. The billet cam had worn the teeth down half way, so there was probably oil full of steel particles getting pumped through my engine. The gears inside the oil pump and the cover plate where also worn beyond spec. And finally, the shop found that my piston to wall clearance was above the max spec.

That would lead to loss of power and excessive oil burning, so I decided to have them over bore and hone the block by .04" (1mm over). I also had them check the cam bore to make sure it was straight, then replace the cam bearings with teflon coated SBC cam bearings from WOT-tech. While I was at it I had them check the heads to make sure they were flat and the valve guides were still good. They said everything held a vacuum and was good, so I decided to get the lighter 3500 valves and have them do a 3 angle valve job, and also machined the spring pockets down .10" to lower the seat pressure with the LS6 springs and allow for more coil spacing at higher lift in the future, then they re-assembled the heads for me with new valve seals and re-used my springs/titanium retainers/locks.

After I got it back from them I put the engine together myself, with an occasional hand from Mac and David (big thanks to them, and to David for letting me borrow his engine stand and ring compressor). Here's a complete run down of the new parts.

-Sealed Power .04" over pistons

-Perfect Circle (Mahle) .04" rings

-one new rebuilt OEM connecting rod

-Cleavite tri-metal crank and rod bearings

-SBC teflon coated cam bearings

-Ishihara/Johnson crank scrapper

-Melling oil pump (w/shimmed pressure bypass spring)

-all new Sealed Power lifters

-LS lifter springs upgrade

-MLS .07" head gaskets

-new Sealed Power OEM replacement cam, stock specs but solid core instead of hollow

-new OEM timing chain

-new OEM oil pump drive assembly

-3500 valves

-Corteco premium teflon rear main seal

-flow matched 42 lb/hr Lucas injectors

I re-used the ARP head studs I already had, and took out the aluminum roller rockers and went back to stock rockers for now. This allowed me to remove the heat treated pushrods (since one was junk anyway) and guide plates. It also made the re-install a lot easier since I didn't have to adjust floating rockers one valve at a time, as well as less noise and no worries about reliability. I had a previous set of stronger chromoly pushrods in stock length that I swapped back in. I put the top end together using the premium fel-pro gasket set with the rubber/metal LIM gaskets.

While I was waiting for the engine to get back I also made some changes to my oil and trans coolers. I added a -6AN 185 T-stat between the trans and cooler, and a -10AN T-stat after the remote oil filter adapter. The oil stat is set up with a plug in the cooler return port and a return line to the engine, then a supply line to the cooler and return line from the cooler hooks into a Y fitting on the return line to the engine. Not having the oil cooler return go through the T-stat avoids false temps from messing with the T-stat operation. Hopefully this setup will help control the oil temps when it gets cold outside to keep the oil viscosity correct. I'm going to be obsessive about proper lubrication with this engine. lol Between that and the higher oil pressure from the new pump I think I should be good. Only other thing I could do would be to add a remote oil accumulator like those from Canton Racing. That would pre-lube the engine on cold starts and avoid oil starvation during cornering at track days. I might add one eventually, but no money for it right now.

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Here are a few more pics.

New piston pressed onto the rod.


Freshly honed cylinder.


Stock versus sealed power lifter internals, with LS springs on bottom.


Fresh repaint on the engine block. The shop hot tanked it after machining and took all the old paint off. Then they put in all new freeze plugs, galley plugs, and oil pressure bypass.


Bottom end all assembled and test fitting the crank scrapper.


Top side with the ARP studs back in and new MLS gaskets, before the head went on.


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I remember watching this all unfold on GAGT. Just another reason why not having a garage blows goats.

The car is up and running, but IIRC, he's having boost issues...

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Cleaned up heads with new valves etc.



Back on the block.


HUGE pile of parts I had before it went back together. lol


WOW! so how is she running now?

It's doing ok. Got a few hundred miles to go breaking it in on conventional oil before I switch back to synthetic. The total displacement is now 209 CI or 3.42 L, so I should pick up a little torque. In the mean time the supercharger drive bearings were squeaking constantly now, and I noticed signs of wear on the rotor tips, so I took it out and am running NA with a temporary intake. Took the blower apart and found scouring in the rotor bores, so I did a light porting on the casing and put it back together and sent it to a place called Embree Machine to get rebuilt. They are going to replace the bearings and seals, and also machine the rotors/casing for clearance, then coat the rotors with a low friction coating and the rotor bores with a thermal barrier coating. All this is supposed to tighten rotor to case tolerance and reduce friction and heat transfer to the air charge to increase efficiency. Hoping for a 20hp gain with the same 2.2" pulley. :D

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Any pics all back together in the car? (with the supercharger)

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Nothing current. Here is one from the dyno session in March. I changed a bunch of stuff during the rebuild though. Replaced all the red wire loom and re-routed some stuff. Changed some of the vacuum and PCV lines. Made a bracket for the 2bar MAP. Little stuff like that. I'll take new pics once the SC gets back.


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Boy thats one FULL engine bay.

FULL of WIN that is!

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Crazy, how much money and man hours went into the rebuild?

Definitely worth putting it back together though, I love this GA

lol, I have no idea. I haven't added it up yet. Many many hours. As for the money, I have the receipts but haven't totaled them up yet. Probably gonna wait until the SC is done since that is going to cost another $800 or so.

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  • Founders

lol, I have no idea. I haven't added it up yet. Many many hours. As for the money, I have the receipts but haven't totaled them up yet. Probably gonna wait until the SC is done since that is going to cost another $800 or so.

wow, hopefully it will be worth every penny :lol:

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  • 2 weeks later...

Yeah, so the latest is... I sent the supercharger out to get rebuilt. They said they could fix the scratches in the case but the rotors were too bad a shape and would need to be replaced, so they had to tack on extra for a new core. Brings the total up to $1173 for the complete SC rebuild. OUCH! A bit more than I wanted to pay, but yeah... hopefully it will be worth it, and it will last a long time.

I did a little more porting work on the UIM and the inlet/outlet casting for the SC, and I also made some modifications to my oil catch can since it wasn't working properly. It wasn't designed properly to begin with. Currently re-engineering the PCV system so that it will still work, but not go through the SC so it doesn't get gunked up with oil residue again. :welcome: It's going to involve rerouting it to the UIM, adding a vent, and a couple check valves to make it all work. Thinking about adding a second catch can for a dual setup to maximize filtration, but we'll see how it goes with one first. More pics when the SC gets back.

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:blink: wow that sucks I hope it was worth it.......

Love she aint cheep date! :lol:

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Damn... sounds like that car gave you a run for your money... glad it is all back together and looking GREAT! you have such a great setup.

One day i want to see if that SC setup fits on the G6 3.5 (LZ4). let me know when you are ready to sell it!


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Still waiting for word on the SC. Might be another week or two. In the mean time I've been working on some other stuff. I got the vacuum check valves I am going to be using to modify my PCV system. I'm going to make it go back to the intake manifold in order to bypass the supercharger and not get all that oily mess in there.

I'm still trouble shooting some other strange issues though. I can't decide if one of my head gaskets is leaking or if there's something else going on. I've got these streaks going down my engine block and something that looks and feels like oil dripping off my A/C compressor and starter. Seems like it's very slowly seeping out from between the block and head.


I've looked everywhere else and had the upper manifold off and can't see it anywhere else. It's only on that front edge. Very strange since only coolant goes through the gasket. They are MLS gaskets from Gaskets To Go who did a group buy through the old 60v6.com store back in the day before Cometic would make them for us. The only possible thing I can think of is maybe they aren't sealed well along the edge of heads and oil could be getting between the layers at the edge of the gasket and leaking around? The heads have oil drain back holes from the top part by the rockers where the oil would pour down over that edge and into the lifter galley. I just can't imagine why it wouldn't be sealed so tight that oil couldn't get in there, and why it would only be leaking from the front edge of the front bank. It's not seeping out the sides of the gaskets or on the rear bank from what I can see. I'm stumped.

The other problem that's nagging me is occasional white smoke out the exhaust. It only happens at idle in gear or parked, but not all the time. Doesn't matter if the engine is hot or cold. I can be out driving and sitting at a light and look in my mirror and see wisps of smoke rising behind the car, take off and it goes away, get to another light and see nothing. Get home and get out and look and see nothing coming out the exhaust, but sometimes I do. The coolant and oil levels aren't going down fast enough (if at all) to tell me what I'm burning. Can't decide if it's another problem with that head gasket, or some problem with the piston rings not sealing well sometimes when the engine isn't loaded. It's really got me worried though. I don't want to have to tear the engine apart again to replace the head gaskets, and I can't afford to pull it again if it's a problem with the rings. I did everything the manufacturer recommend though with the rings so I have no idea what could be wrong. I guess at this point this engine just has me paranoid. :agreed:

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Nope. They are the same on both sides.

I think I'm gonna do a compression test this weekend and see if I find anything, but I'm leaning towards replacing the head gaskets too. I don't know if there was some kind of design flaw with them or what. Of course if I do change them, then the question is do I pay the extra cash and wait for a set of Cometic MLS gaskets and hope that they don't have any problems? Or I do go the cheap route with OEM gaskets that I know will seal up good, but might blow out again in the future?

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  • Founders

Do you know other people with the Cometic MLS gaskets? Could you ask around and see if other people are having this problem? That might tell you either to pay for them again or go back to OEM

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These aren't Cometic's, but yeah... I have a thread open on 60degreev6.com about the problem. So far I haven't heard from anyone having problems with either kind. Everyone is saying things like "did I check the surface finish" and "you need to mill the heads" blah blah blah... I guess no one bothered to read my first post where I told them the engine shop that did my machine work told me the surfaces where ok and the heads where flat and didn't need milling. lol

Besides that milling would up my compression which I don't want on a boosted car. They are also telling me I need to take the gaskets apart and spray them with some kind of copper spray... no idea why. I'm getting kinda pissed off about the whole situation though. If that was required shouldn't it have said so in the directions? Nope... all it said was it needed a surface finish of 50 RA or better, so I would assume then that they should be bolt on and go.

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So it turns out they are insisting the stock heads are not smooth enough or flat enough, even though my machine shop said they were ok, and that those head gaskets won't seal properly unless I get the heads milled.

Unfortunately I don't have another car to drive so I can't take the heads off and send them out again. I can only do what I can get done in a weekend, which is take them off and switch back to stock head gaskets. So it looks like I won't have MLS gaskets and will have to worry about blowing the head gaskets again if I'm not careful enough. :dancingpontiac: Not happy about the whole situation. They should have told me that was required in the first place... both the machine shop AND the seller.

Anyway, here's something else I was working on last weekend. I wrapped the fuel rails in heat reflective foil and covered the supply and return lines in heat reflective tubing. Both from DEI. The gold foil reflects 80% of radiant heat and is good to 850 degrees. :) I can put my fingers on it when the engine is hot and the fuel rail is only warm. Hopefully that will drop the temp of the fuel a few degrees and help cool the air charge better and help reduce KR.



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