New Gaskets for my L99 in germany

[Warpig]

Hi guys,

I think i blew my head gasket. Have a boiling coolant bottle, air in the cooler, 120°C water temp from time to time, i refill water on a regular basis.
(For 2 weeks now)
Slight blowby gases in my coolant water so far, no oil though.
I thought about going with a slight bump in compression, from the stock 0.051" to 0.048" with stock heads. Will change heads next year to gm performance heads, over here in germany they only use them and dont like other stuff like trick flow etc.

Since i am appearently too stupid to use online compression calculators, what can i expect in compression afterwards?
Any hp gains even if they are small?

Have longtubes 1 7/8", 2,5" borla catback stype, 200cell metal cat's (cant go without in germany or jail time), fast lsxr 102 mm throttle body and intake manifold, new ac delco sparkplugs and cables, camaro z/28 intake manifold and a nice tune so far.
Havent touched the injectors, fuel rail or fuel pump yet (do i even need to yet?)

Any suggestions?

Thanks in advance, have the car since 2013 and i still love it as much

[christianchevell]

My advice would be to ditch AFM/DOD and use the CNC ported stock heads available for like 1300-1400$ with hollow stem intake valves and stay at the same thickness head gaskets as the very slight compression bump would mean nothing in terms of power...


IN Germany it will get very cold in the Winter so you want it fixed with the correct 50/50 mix in by winter. I would also recommend you go to bushings in the rockers instead of the stock or comps needle bearings many have done this upgrade on here trough varied makers. You may want to check the tune is right and the fans are switching on when expected, most alter on a hot rodded car the fan to turn on earlier in the tune along with running a 160 degree thermostat. Checking and changing out the thermostat and radiators cap are two quick and easy things to do to make sure its not them first. Good Luck

There are many who have ditched and varied vendors sell kits to do the AFM delete as the lifters are more prone to be damaged over time and its cheap insurance to keep the engine good in the long run. You will want to carefully inspect the pushrods on disassembly and such who ever does it and will need a ls3 valley cover under the intake to ditch AFM along with ls3 lifters and maybe some new buckets which are plastic trays to help the lifters align right. Just some advice ;read up on the motor threads and this is just a few of the most important things I would have done had I kept my 2011 l99 I owned. L99's have solid stem intake valves and thus a lower upper rev. limit than a ls3 and also slightly different compression and cam.

https://www.bing.com/search?q=pressu...vdqa5f&plvar=0

[Warpig]

@christianchevell

Thanks for your answer.
I already programmed out afm/dod and bought trunnion rings which are massive, no comp or other company stuff with needle bearings since they can fail on you, i've read.
Tune was ok the last time i checked, got my engine "fixed" by a corvette tuner in austria, drove 1000miles to get that tune lol
So i should go for the sodium filled intake valves like the ls3 has?

Fan works flawlessy, the thermostat opens up at 92°C (should be fine)
Radiatorcap is good too, aswell as the pressure in the coolingsystem. I put 1,5bar on the radiator and it hasnt lost a bit in pressure, which would be a sign of leakage somewhere. It really seems that as soon as i wot/ have a "hot" engine, the heads lift a bit and allow blow by gases to pass through

So AFM delete kit is my next goal then,
And i"ll measure the pushrods when i already open the stuff up, should i go with stock ones or upgrade them to titanium, since i want to cam the car sometime next year?

If you dont mind, could you link me a shop which sells the "buckets" to align the lifters, cant seem to find any.

My car has run 120000miles already and so far, other than the head gasket, i had no issues

[christianchevell]

A retorque of the head (gaskets) bolts could maybe solve the problem as the expansion and contraction of aluminum is a very known issue when its mated to iron, but the heads to an aluminum block could still expand and contract at dissimilar rates dues to size of material....
https://gwatneyperformance.com/ the baskets are a stock product and you may wish to talk to good shops and alter to johnsons lifters and well what ever you decide with help.

https://www.tickperformance.com/ https://jannettyracing.com/ https://shop.tampatuning.com/ https://rdpstore.com/ https://www.livernoismotorsports.com/ https://www.lingenfelter.com/ https://www.texas-speed.com/default.aspx? http://www.cammotion.com/ other places come to mind summit, jegs, etc etc etc... and of course phastek and the very best for show American Car craft...good luck.