Dorman 615-901 Engine Intake Manifold Compatible with Select Cadillac / Chevrolet / Pontiac Models

A little modifying needed but nothing terrible. I haven't dynoed it to compare with my old numbers but it wouldn't matter because I have done a lot of other things since then.

If you are lucky enough to get one of these without a manufacturing defect, then it is perfect and does the job just as well as a FAST intake does. But beware, see the pic I attached, there are two common defect spots.

I have experience in building LSX motors with both stock and aftermarket type manifolds. I know people are anxious to get more value for their money and get a few more ponies for a few less pennies. Unfortunately Dorman really missed the mark with this one.For starters the most important aspect of the manifold: the upper plenum is a molded plastic. This is usually fine, however this low-cost plastic does not hold up to torque or heat well. I will get into how this becomes an issue soon.The kit includes good gaskets, the same found on most FAST manifolds. New injector o-rings are supplied, but Felpro's kit is superior to their included gaskets so these are not worth installing.The manifold forgot to include an additional nipple for GTO's which require HVAC to operate off a vacuum. I had to create my own T-adapter, but this should have been included as most LS2 intakes have this provision.The fuel rails, because of slight differences on all LS2 equipped cars, have a L adapter that Dorman included on 4 points. This adapter fits between the fuel rail and one of the manifold bolts to work as a hold down. While this is a good idea, in practice you need a solid mounting position to hold the torque of both a fuel rail and a plastic manifold. Here is where the plastic construction fails.The bosses collapse under even proper torque load. Yes at the 89-100 in pounds it cracks. When this cracks it places additional strain on the fuel rail adapter L-brackets and forces leverage on the injectors. This causes your injectors to unseat during WOT runs or worse, the upper injector o-ring to give way and fuel to spray all over your engine bay. This causes not only for the car to stop, but extremely dangerous exposure to fuel and spark conditions.I know the temptation is there at the $400 dollar mark, but trust me. GET A FAST intake or just convert your 3rd gen heads to 4th gen heads with a new L92 or LS3 intake manifold. This Dorman intake is just simply unsafe and will crack, causing you at least an afternoon to remove it, or at worst a fire and possibly a new vehicle purchase.

Better than a GM LS2 intake, and cheaper too. Nice quality, decent price and inexpensive upgrade for an LS based engine.

I had great experience with the Dorman LS2 intake. I bought mine from Rockauto though. This intake is a direct replacement on the LS1. Stock Fuel rails and injectors bolt on. You will need a 4 bolt throttle body. A 92mm will fit.

Had to return the first one due to poor quality only to receive a second one of just as poor quality. The inside runners were not properly aligned and had gaps in them. Not acceptable when the purpose of the order is for performance upgrade.

At the original price point of about $350, it was a good buy. No major issues but not OEM quality. At $900, this is a joke. I'd give it 4 stars at the original price, but one star at current prices.