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Old 10-10-2010, 12:05 PM   #1
Drew888
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2008 LGT Spec-B stg4
Delicious Tuned 336/336

Default Built bottom end & builder is offering 1mm oversized valves ? Should I....?

Serious oil burning and power #'s are not great in a Spec-B that is now having a motor built (teardown starts tomorrow).

All I intended to do in the bottom end but having about another $500 or so to spend I ask the builder "what else" and he suggests 1mm valves.

Never having been down this road I have no idea what a reasonable expectation is after the upgrade is done.

On an otherwise stock head (no intention of hitting 7.7-8k rpms) should I save my $500 or go 1mm over?

Thx

-Drew
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Old 10-10-2010, 05:06 PM   #2
trxdam
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If he backed those up with some porting and polishing i would say yes...... Otherwise what's the point? What do you use your car for/what is your driving style/do you weekend race??

Also what are your current mods?
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Old 10-10-2010, 05:37 PM   #3
timeXlost
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what are your plans for the car? what are your power goals? do you plan on buying cams too? if you do go oversized, be sure when you time the motor be very very careful your cams dont snap around. if they do there is a chance (a very good one) that the valves can come in contact with eachother and bend.
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Old 10-10-2010, 06:25 PM   #4
Drew888
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Delicious Tuned 336/336

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Thanks guys, power goals are modest at best.

Basically, HTA68, 850cc, custom Walbro, KS-Tech intake, Grimmspeed header/crossover & EBCS, FMIC, Cobb HFC DP, Perrin mid/Y, Prodrive cans.

Spirited street and the occasional 2-3 HPDE/yr that's it. I'm also satisfied with the HTA for now.

I'm feeling that the minor gains in valves only at this point aren't justifying the expense. It's also making more sense to pick up an HKS Camp II and a couple extra sensors instead.

Provided he can install and adjust correclty anyone have an idea of what's gained doing the valves only. At this point I'm just curious. It's certainly easier to go a bit larger on the turbo if more HP/TQ is needed.

-Drew
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Old 10-10-2010, 06:38 PM   #5
trxdam
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I would say at that level some form of water/meth/alch injection would be nice, especially on those track day's to keep those temps down... Cams would be awesome for making power everywhere if you wanted something that was worth it in the heads, but unless you find a used set they are probably out of the price range....

What are you rolling on as far as suspension and body wise, can't ever hurt to get something that makes you faster in the corners....
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Old 10-11-2010, 12:28 PM   #6
Drew888
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Old 10-11-2010, 05:47 PM   #7
FuJi K
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Your turbo is too small. Add a little boost and it'll make up for it. some decent 264* Cams will bring out more than the valves will. As of right now, you do NOT need them.
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Old 10-12-2010, 03:55 PM   #8
Drew888
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Delicious Tuned 336/336

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Thanks for that! I'm glad you chimed in.

PM'd ya
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Old 10-12-2010, 06:12 PM   #9
project_skyline
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Quote:
Originally Posted by Drew888 View Post
Thanks guys, power goals are modest at best.

Basically, HTA68, 850cc, custom Walbro, KS-Tech intake, Grimmspeed header/crossover & EBCS, FMIC, Cobb HFC DP, Perrin mid/Y, Prodrive cans.

Spirited street and the occasional 2-3 HPDE/yr that's it. I'm also satisfied with the HTA for now.

I'm feeling that the minor gains in valves only at this point aren't justifying the expense. It's also making more sense to pick up an HKS Camp II and a couple extra sensors instead.

Provided he can install and adjust correclty anyone have an idea of what's gained doing the valves only. At this point I'm just curious. It's certainly easier to go a bit larger on the turbo if more HP/TQ is needed.

-Drew
For that power level and turbo 1mm oversize valves on stock heads and cams will yield no power gains at all.
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