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317 or ported 241s?

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Old 12-01-2011, 01:39 PM
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Default 317 or ported 241s?

I am putting an lq4 in my ta, I have a set of ported 241 heads with 2.02/1.60 stainless valves, comp springs , and also the set of stock 317 heads off the lq4. I was planning on using the 241's until I got to reading about how the 317's flowed so much better. I will be running a tr 224/230 111 cam. The heads were on the car when I bought it, the guy said they were lvl 2 ported, but didn't say by who.

Basically I don't know if the higher CR of the 241s would offset the lower flow. And can I mill the 317s enough to get decent CR?

So i have a few options.

Run the 241 set, sell the 317 set.

Get the 317 heads cut to fit the2.02/1.60 valves, swap valvesand springsto the317,sell the241.

Run the 317s with stock valves and sell the 241s with the ss valves.

Opinions?
Old 12-02-2011, 12:38 AM
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Bore size has a lot to do with flow numbers , Ii was on the same boat your in ... I pulled my 317's off my lq4 and went with some ported and milled 853's , IMO it was well worth it
Old 12-02-2011, 07:37 AM
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Thanks, that's what I was kind of guessing but I really didn't know. Have any idea how much your heads are milled?
Old 12-02-2011, 07:45 AM
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If those 241's are ported coupled with those valves, I'd run them. A ported set will be right there with some stock 317s on flow and the compression will help a lot.
Old 12-02-2011, 07:50 AM
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Good, that's what I wanted to hear!

Anyone know what I can mill these before usually running into ptv issues? I know I will need to check them but I want to get the highest compression I can with these dished pistons. I will flycut if needed.
Old 12-02-2011, 08:05 AM
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My heads are at 59cc and I believe there milled about .050
Old 12-02-2011, 08:06 AM
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You had to flycut I assume?
Old 12-02-2011, 09:21 AM
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No sir ....my cam is a 228/232 .612/.600 111+3 LSA ..NOT SAYING MILLING WILL BE PERFECTLY FINE ON YOURS, But I haven't had any issues with it ...
Old 12-02-2011, 09:26 AM
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That's good news. I will for sure check ptv clearance issues but if I don't have to flycut that saves me some time. Have any idea what compression you're running?
Old 12-02-2011, 10:16 AM
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I believe its about 10.8:1 with stock head gaskets ...bexouse of so much milling on the heads I did not want to run any thiner gasket ...


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