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Something else just occurred to me looking at the new chart: at the strip I'm shifting waaaay too late. I have my shift light set at 6500 so I'm shifting at 6500. I should be shifting closer to 5800-6000. That alone would probably improve my 1/4 mile times. Power doesn't drop off a cliff, but I've been taking it well beyond the power peak of the cam. I learned with my old Chevelle that winding the engine out beyond the power peak was making me slower. I'll have to try to remember this my next time out.
i don't think that's really true. FSAE_junkie had a thread a long time ago about shift points, and you actually want to wind it out with an LS. When you upshift, you reduce torque to the wheels because of the gear ratio change. just because your past peak engine power or torque doesn't mean it's time to shift into the next gear, because you may still actually be putting more torque to the wheels in the lower gear than if you shifted to the next higher one.

he showed you end up with more torque to the wheels "under the curve" shifting as high has you can in each gear. (well, it just works out that way for our engines, this is not meant to be a general rule!). it may not be the case in other vehicles with torque curves that favor the lower RPM ranges and differently spaced gearing, but it tends to be true in our cars.

 

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I also wouldn't get TOO hung up on dyno numbers. the old addage is that it's just a tuning tool, and to stick with the same dyno for consistent results. you had a nice gain and that is what counts, not so much the actual number.

i have a funny feeling if you took a drive and went to CSP, you'd dyno closer to 400.
 

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I was going to say that you should run your rpm past your hp peak because its easier for the engine to pull a few hundred more rpm past it and when you shift your rpm doesnt drop as low as it would if you shift earlier. Dont overrev it to the point where it falls on its face tho.
 

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Discussion Starter #24
Well, I can try it both ways and see what the results are. G-Tech = no waiting in line! Just wish the roads weren't so dirty and dusty. Going to have crap weather for a week upcoming, but lots of rain forecast so that should help if we get at least one good gully washer. My biggest problem was and still remains getting a good launch and traction off the line.
 

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Discussion Starter #26

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Greetings Rich & all; I think I read it all & some posts more than once! Thank you for the unusual idea? I just started uncovering (blankie's off) mine last night, WOW. As I had finished putting it back together. Kinda a pre run for this coming fall's thrash (Mod Fest). Ok I don't have the energy or speed to call it a Thrash any longer. I have purchased an X-Air inlet box, radiator top cover, fan-shroud assembly & lower radiator pads. So that's all pre fit now & ready for radiator drop. Anyway this idea of another .1 rocker ratio & 5 axis ported heads has me torn up inside my brain. I Love non OE cams! Thanks Ole' Bob. Ps: picture of my first cam swap, I always seem to do a bit more once stuff comes apart!
500921
 

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Discussion Starter #28 (Edited)
Bob, is that small block sitting in a tri-five?

You know, one thing occurred to me, ATF has an X-Air, I have a DuSpeed. And while the DuSpeed is well made and looks great, it does have a pretty small air filter, though it is a high flow K&N filter. But I have to wonder if my numbers would have been better if I still had the Vararam on there. VR has a MUCH larger filter area.

Also, he has 3.91 gears, don't know if that makes a difference in how a dyno reads vs. my stock 3.42 gears. Biggest difference is probably just two different dynos, but these things crossed my mind.
 

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i've thought about the filter area issue with my svede. i modified it for a slightly larger filter. i don't think it made a difference.

you could always go with something that has more pleats per square area. or put a steel mesh in place of the filter.
 

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Discussion Starter #30
I've tried to find a better filter, not really a fan of K&N and I've removed them from any other car I own that had one on it. The filter is for a mid-2000s Mecedes 4 cylinder with a blower. Filter only fits the Euro version, States version has a different sized filter. This makes finding a filter next to impossible. Green doesn't make one in an equivalent size and shape, I even tried to find a WIX version but it was too thick/deep to fit in the DuSpeed. I even asked Green if they could custom make me one, never got a response.

I also like how the Vararam when properly sealed to the hood also pulls air in through the hood scoops. I actually like my old Vararam, it was just so darned ugly. I never ever saw anything more than 10 degrees above ambient even when idling with my old VR.

I could probably sell my DuSpeed for enough to pay for a VR and a new radiator shroud to cut up.
 

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There was a discussion (that i was flamed on) back in the day about hood scoop air flow.

GM says the scoops are for heat extraction. Dunno how true that is, but airflow theoretically would be over the radiator and out the scoops.

I think the vararam works because it gets air from the same place the other OTRCAI's do. I think the hoodscoop thing is just a gimmick.

I've never sought to prove it tho.
 

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Discussion Starter #32
My Vararam filter had dirt spots (it was a washable filter) exactly where the scoops were. I opened up the rubber plugs to allow for more direct air flow. The dirt pattern on the filter pretty much convinced me it was indeed pulling in air via the scoops.

500981
 

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if you say so.

i still have that magnehelic i puchased like umpteen years ago. i'll use it one of these days to test the pressure areas on the hood.
 

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Greetings Rich & all; Ya my first engine & car. A 301", it was zippy as I could keep up with my buddies 1963 340 HP Vette, meaning I would be on his back bumper. Time & time again we would race. Back to X-Air & VR air boxes. I haven't done the area, Sq In of opening on my new X-Air yet. But it sure looks small to feed 400 HP. But then I'm use to the cowl hood opening on the Bronze Brick feeding 480 HP. I used the NASCAR base of windshield as a reference. Don't quote me on this, cup engine 750 HP being feed by a 3" x 16"?? About 48 Sq. In". So if Ya make 60% (440 HP) as much power (wishful thinking) as a cup engine. We would want 29 Sq. In.'s. Ya, Ya I know apples & oranges as the cup car has More pressure at the windshield base than we have behind the grill. So maybe we should have 35 Sq. In.'s. And it's with, just sayin' we also have an filter element! OK now my brain is going, What's the area of the OE tube 5" Diameter? I better stop for now, Ole' Bob.
Ps: The 55 for fun. Note the date.
500983
500982
 

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Hey Guys; Rich I sure like the way the VR fits. But the air sure has to make some tight turns. Did you lower the radiator?
 

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Discussion Starter #36 (Edited)
Hey Guys; Rich I sure like the way the VR fits. But the air sure has to make some tight turns. Did you lower the radiator?
Nope, did not move the radiator though I did trim the fan shroud per VR instructions. I DID work that VR again and again to get it to fit better and better. It took a lot of trial and error. I also insulated the bottom of it and sealed it to the underside of the hood and around the TB. One very good thing about the VR is that it encloses the MAF keeping it also shielded from engine bay heat.
 

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Greetings Rich & all; Ya my first engine & car. A 301", it was zippy as I could keep up with my buddies 1963 340 HP Vette, meaning I would be on his back bumper. Time & time again we would race. Back to X-Air & VR air boxes. I haven't done the area, Sq In of opening on my new X-Air yet. But it sure looks small to feed 400 HP. But then I'm use to the cowl hood opening on the Bronze Brick feeding 480 HP. I used the NASCAR base of windshield as a reference. Don't quote me on this, cup engine 750 HP being feed by a 3" x 16"?? About 48 Sq. In". So if Ya make 60% (440 HP) as much power (wishful thinking) as a cup engine. We would want 29 Sq. In.'s. Ya, Ya I know apples & oranges as the cup car has More pressure at the windshield base than we have behind the grill. So maybe we should have 35 Sq. In.'s. And it's with, just sayin' we also have an filter element! OK now my brain is going, What's the area of the OE tube 5" Diameter? I better stop for now, Ole' Bob.
Ps: The 55 for fun. Note the date. View attachment 500983 View attachment 500982
Sweet car! My dad had a '55 Chevy 2-door hardtop Bel Air, white/red with Monte Carlo swivel bucket seats. We flew out to Iowa in the early 80s to buy it and drive it home. I spent some money having floor pans and 1/4 panels replaced, and my parents gave it to me as a college graduation present. I took my wife on our first date (to her senior prom!) in it. Fun car to drive, easy to work on, but I sold it a few years after getting married since I didn't have the money to do a ton more bodywork that it needed.
 

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Rich I have a Vararam tray and filter you can have free of charge, just cover the shipping cost. PM me. As far as shifting, I shift right at 6500 when I am serious/racing someone and I've hit the rev limiter at 6700 spinning in first going into second and still spinning which I attribute to the 3.91's. 20200321_214129.jpg
 

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There was a discussion (that i was flamed on) back in the day about hood scoop air flow.

GM says the scoops are for heat extraction. Dunno how true that is, but airflow theoretically would be over the radiator and out the scoops.

I think the vararam works because it gets air from the same place the other OTRCAI's do. I think the hoodscoop thing is just a gimmick.

I've never sought to prove it tho.

Our scoops do function as heat extractors and they work fairly well. Watch this video here from a guy who was integral to the 2004-06 GTO's development. The audio is poor however. When you remove the plugs it works better, they are there for keeping water, dirt, dust, debris out of the engine bay. Skip to around 31:30.
 

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There was a discussion (that i was flamed on) back in the day about hood scoop air flow.

GM says the scoops are for heat extraction. Dunno how true that is, but airflow theoretically would be over the radiator and out the scoops.

I think the vararam works because it gets air from the same place the other OTRCAI's do. I think the hoodscoop thing is just a gimmick.

I've never sought to prove it tho.
Pics!
Screenshot_20200321-221533_YouTube.jpg
Screenshot_20200321-221601_YouTube.jpg
Screenshot_20200321-221617_YouTube.jpg
 
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