Engine SwapEverything about swapping an engine into your Third Gen.....be it V6, V8, LTX/LSX, crate engine, etc. Pictures, questions, answers, and work logs.
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1991 RS/SS is right. You want your intake runner size to match up with the rest of your combo... cam, intake, gearing, rpm range ect. Without knowing the rest of your combo and your intended usage of the car its hard to give a good answer. For example I would get the 200cc version if you are building a 400-450HP 388 that you are planning on shifting around 5500RPM's using .525lift 225dur.@.05 cam, 3.55gears. That combo would be a very street friendly torque monster and an easy mid 12 sec 1/4 mile. If you are planning on going more radical than that(450+HP, 11sec) I would step up to the 215cc heads to allow your engine to breath better at high rpm's and match up better to a higher lift/duration cam and steeper gearing ect. And if you are like me and always wanting to make changes and go faster the 215cc heads have more potential even if they aren't an ideal match at this point..just something to keep in mind depending on your long term goals. If you are looking at getting your heads ported I would recommend Mike Start at CFM performance, he has a shop in Gasoline Alley here in Indy. He does great work for a reasonable price and is very knowledgable about engine combos.
If you are planning on running a cam that big I would definately go with the 215cc heads. I'm not that familiar with the LT1 intake to know how well that matches up or the injectors. I'm assuming you are talking about the XS-290S(mechanical flat tappet cam 252/260@.05, .540/.588 lift)..its the only 290 XE cam I see in my catalog. If you are going to be driving the car that much you might want to go with a smaller cam and maybe something thats a hydraulic roller but that also depends on the amount of driving you do, and how important idle quality is. For a daily driver I would probably go with XR-282HR 230/236@.05, .510/.520 lift, if you stay in the 230's in duration it makes tuning much easier and idle quality is better but it will still sound good with a noticable lope at idle. Since you are going with fuel injection you may want something slightly different, I'm a carb guy. Maybe someone more familiar with FI combo's could suggest something better for your application? I always think in terms of carbs since thats what I'm familiar with.
For a 230 on the intake a 200cc matches better.
For a 240 plus cam the 215 would be better.
Also, the 200cc has a felpro 1205 size port which fits the Lt1 intake after a port match.
The 215's take a 1206 which will not fit the intake w/o having
extra material welded on to cover the bigger port.
Plan on $150-$200 to have that done.
__________________ 00 S10 416 LS3 4L80E AWD - in progress
89 GTA 355 A4 sold
69 rS 383 A3 sold
68 SS 468 M4 sold