Does anyone have any experience with either of the two motor builds available from AMS? I am contemplating the AMS 2.4L for street use spinning an EFR 8474 turbo. Also looking to make well over 800whp above 40psi. I know that a few people had issues with blowing head gaskets with larger bore setups especially on high boost. AMS is claiming that their motors will hold up to 40+ psi and the website states that the build includes "AMS spec big-bore head gasket". Since they had custom cams made by Kelford, am I wrong to assumed that they had some special headgasket made as well? Could this possible AMS spec headgasket hold such PSI without failure? I have not seen many post from AMS 2.4L owners so its hard to find good info. AMS also assured me that I would be able to rev the big stroker up to 8500rpm with no issues. My 2.2L stroker revved to that rpm and was a blast to drive and I would like to see how much more responsive a 2.4L would be with the same turbo setup.

Also, any thoughts or input regarding the differences between the AMS TMP vs GSC S2? I've had the S2 for some years and I think the TMP are suppose to be a little less in lift duration? If so then they should provide more low end trq? I would like to keep my GSC S2, but AMS only offers their spec'd stuff in the build.

 

I have the 2.2 big bore on a 5858. I'm only revving to 8k right now. I'm pretty happy with my 510whp on 91
I had a couple times I went to 30 psi, with no issues. I've also had to do quite a few cold starts below 32F. I've scoped my cylinders with very little wear on the sidewalls, and oil consumption (with the exception of a frozen catch can incident) has been literally none on a 1,500 mile 3-4k rpm cruising road trip.

My boost starts coming in just north of 3100, and at full boost by 3900 with the kelford cams and 2.2L big bore.

I'm not too comfortable about what would happen if I need a head gasket, but apparently dropping a sleeve would be more likely according to Kozmic.

 

Any plans on going up to 40 psi or so? I am curious on how the head gasket will hold at those boost levels and for how long. Did Kozmic do your build?

 

I tuned a 6262 setup on an ams big bore motor years ago for track use. Little under 800hp at 34psi.

That thing couldn’t keep a head gasket intact even on the “low” boost map of 30psi. Which for anyone that knows anything about 4b11’s, it’s almost impossible to kill a hg on a normal sized bore.

Obviously, one does not make all, so take my experience with a grain of salt.

 

Interesting. They claim that their spec head gasket should hold up to high boost. I might just build another 2.2L and keep the stock bores to keep things safe. I would love the extra grunt of a 2.4L though, but I guess we can't have it all. I was hoping that they had some special head gasket that addressed any possibility of failing. O-ring the block doesn't help?