So here's my story. I boosted my car about 2 years ago. Specs on my car are in my sig. Sooooo after about 2 years and 18k miles the inlinpro headgasket is now blown. I know I know never should have went that route... Yah yah... Reason I went this route cause I didn't have money to rebuild my bottom to lower comp n instead I went the cheap way out n got the head gasket For 250 vs A lot of $$$ to properly build the bottom. Anyways now that I'm gonna install a new headgasket. I'm weighing in my options. Should I option 1 be super cheap n just replace head gasket wit same 1 n call it a day. option 2 order an oem1 up my compression back to stock n do a retune. Option 3 oem gasket up compression back to stock n add a lot of supporting valve train mods n do tune??? I figure since I'm cracking the head open I might as well throw some valves, dual valve springs, titanium retainers..... Anything else's u guys think I should throw in there while it's open? Have any of you guys with boosted rydes upgrade your head??? If so what kinda brands should I lean towards that has been tested n actually makes power. Also have anyone thrown in turbo cams? I can't seem to find any1 or photos of turbo cams that have been dyno tested to show gains..........


I'm just lookin for people's opinions on products that they actually run. Just trying to Compare around n see what the best brands out there that make power. Only interested in people's opinions who have there rydes Boosted thanks for any opinions n help in advance mike......


Oh yeah if your wondering about the gasket, I do oil changes every 3k, and all regular maintenance myself, I take really good care of the car but I do beat da s** t out of her lol 9k shifts all day hahaha... According to what I've read about this gasket. I knew when I first installed it that it was never gona get to around 20k. Any ways thanks for reading n Any inputs about supporting mods n opinion s are welcomed. Let me hear wat cha runnin n wat u think about em

 

I wouldn't do titanium retainers.. they don't have the same long lifespan as regular retainers.

I'd recommend an OEM headgasket and a retune.

 

If I get oem head gasket n jus done retune how safe hp wise are we talkin wit just a stock. Ap1 head?.. 400-500???

 

its not. there tons of debate on high compression turbo engines. just save yourself the headache and get some dished slugs from manly or whoever makes an FRM ready slug.

 

There is a limit to what power you can safely make on pump gas before you run out of a timing compensation window, to keep your engine from detonating and destroying itself. Common consensus among us is about 14-15psi max on stock compression with 92 OCT. But the detonation threshold changes depending on cylinder temps, so depending on your IAT cooling efficiency, AFR and exhaust restriction etc will have an effect on what you can safely extract from your set up, and a good tuner will be able to read this on the dyno and tune your car accordingly, because ultimately its the tune that is going to dictate your success. Mechanically our engines are very strong, with the fuel type being the limiting factor on power. 450ish whp on pump and 550+ on E85 or race fuel on a stock engine is regularly done successfully. There is a few crazy s2k guys that have had fun managing to push this stock motor to the 800whp range. I don't know how many miles they will ultimately get out of it, but its done.

With that, the stock HG has proven to be the most reliable at any power level, ARP head studs are not a bad idea as they are meant to take higher cylinder pressures beyond what the stocks will hold, and if your running high boost you could lift the head and blow out the gasket like you have done. I run them on my SC set up with stock HG and have seen boost as high as 19psi in the cold winter temps. I run a slightly lower comp motor at 9.6:1 on pump gas and some water/meth injection for added safety margin.

So I think unless you want to rev the motor beyond the factory limit, the head isn't worth touching, other then upgrading the valve keepers and retainers to the better ap2 version, which is not a bad idea. You should run arp head studs and oem HG. If you have a good tuner lined up, find out what boost level he is comfortable tuning your personal set up on at stock compression with pump gas. Generally with the right boost pressure and tune, your better off running an oem engine that hasn't been cracked open. But since you are, its worth exploring building the bottom end up a bit at a lower compression to be able to run more boost more safely on pump gas if you have the cash. The head isn't your limiting factor on power capability in large part.

 

a higher compression ratio is a more efficient and more powerful engine. It makes no sense to lower compression ratio to lose HP, and to compensate by adding more PSI and more lag.

I suggest going with OEM HG and stock compression. If the tuner gets detonation, then lower the boost... you should get the same HP result with a more efficient engine with less lag.

 

the theory is that some of the unburnt fuel in a lower compression motor is actually enegry that can be used to spool the turbocharger and lower peak cylinder pressures avoiding detonation in a non-direct injected motor. like ours.

i didnt say i believe it, but theres got to be a reason no one makes a 12:1, non-direct injected, turbocharged motor from the factory.

highest comp ratio on a factory non-direct injected motor ive ever seen is 9.8:1...and thats a rotary. maybe its 9.5 but either way

 

Sadly this isnt true, especially if your planning on running pump gas. The lower compression adds a larger window for more boost and timing which that will overcome and yield substantially more power over keeping the stock compression and less boost and less timing. But it depends on what your power goals are. If your only planning on wanting 400whp, then you haven’t exceeded what the stock compression and pump gas can handle yet, so yes in this case the stock motor will be more efficient and should yield the same power at slightly less boost. Much beyond 450whp/pump power goal, that window is near gone and so you would want to lower the compression to open that window back up and make more gains and safely. Or the alternative is run a good water/meth kit with pump, E85 or race fuel.

There is a point where you run out of the ability to retard timing to keep detonation at bay. The tuning window becomes very small, too much timing and you detonate the motor, not enough and the cylinder temps go up and you melt valves and pistons. The more compressions, higher boost and poor fuel you run, that window between too much timing and not enough timing can be too small to read and get right or non existent at all.

 

Thanks for the info.. I learned something. The engineer in me just finds it silly to drop compression since that's the basics of creating power in an ICE.

 

Yeah man