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Message: [QUOTE="KCTurbos, post: 925648, member: 13852"] I understand where you guys are coming from and I agree to a certain extent. I have talked with a lot of guys recently that have had problems blowing gaskets. Many of them have large vgts, but other have large non vgt singles, and also compounds. Many of the guys running large singles get just as high if not higher back pressure than the vgt turbos guys do. Back pressure is a funny term that gets thrown around but very very few people actually run a back pressure gauge and actually know what is going on (factory gauges are limited and misleading). Also there is no way to increase boost without increasing back pressure. You cant make 50psi of boost on 30 psi of back pressure. I know plenty of guys that see 100+ psi of back pressure coming from a large single non vgt on a hard acceleration... vgts are not the only culprit of back pressure. Although something that a vgt turbo can achieve that large single non vgts cant is super high boost at super low rpms. VGT turbos typically have the ability to reach maximum boost much lower in the rpms band. This causes super high pressure ratios at a much lower flow rate. This can equate to having more pressure in the cylinder at lower rpms before the motor gets spinning and flowing more air. 45psi at 2.4ms of fuel and 2800 rpms is way different then at 3500 rpms. Orings and Fire rings also serve different purposes. One of the purposes that both of them share is it directs the pressure from coming from the head/studs into a smaller area. This in essence would help the gaskets not to blow even if the head flexes a little bit and/or the stud stretches. That oring/fire ring will be the last thing that touches before the heads blow. We are talking very small measurements... but it does not take much to blow a gasket. Much of the reason our heads are blowing comes from the head flexing and not just the stud stretching. Even the best stud in the world will not stop the heads from flexing in between the cylinders (boy do I wish we had more head bolts). But if you were to put fire rings in that area... theoretically while you are torquing down heads/studs the first thing that the head touches will be the fire ring. It will have the most pressure pushing back against the head in the fire ring area. When the head flexes and/or the stud stretches the fire ring area will have a little rebound from the extra pressure and help the gaskets not to blow. [/QUOTE]