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My car has a gauge that I can view IATs at just a glance.
I just did about 90 miles today with the Halltech. Our temps today are between 81-86 degrees (it's going to be a hot summer!). I was stuck in plenty of traffic over black asphalt plus the car was idled and revved for about 5 minutes while observing an engine scan.
IMO, the Halltech is the same temps as the Vararam while moving, rolling slowly or briefly stopped, but the IATs seems to be warmer than a recall the Vararam being when really stuck idling. The highest I saw was 41 degrees above ambient with the Halltech.
I have not seen the dyno charts but I'm told the Halltech did dyno about 5 hp more with a very powerful 60 mph fan blowing on the car. I hope to get a copy comparing the Vararam and Halltech dynos to post. Dedicated Motorsports specializes in building custom turbo kits that utilize intercoolers so their dyno fan is designed with that in mind and accurately imitates 60 mph speeds. How can an CAI make 5 more hp if the first CAI shows no restriction? I dunno?
To be fair I've only had my car 6 months and only had the Vararam from about October to January (cool months) of this year. On a mid 80 degree day, on dark asphalt, do you guys see 40 degrees above ambient with your Vararams.
I suspect if drag racing during the summer or even light to light the Vararam might offer initially cooler temps and therefore more timing and acceleration.
I prefer the Halltech. It was 5# lighter, it was easier too install and reverse if needed, it looks better, it doesn't block the condensor/ radiator, it makes more hp on the dyno, and it's less likely to ingest dust or water due to it's location and massive filter surface area.
To provide a more fair report, you'd need to tape over or some method to cover the 3 large holes you put in your new shroud, since that's a personal mod in addition to the Halltech CAI. The good thing you'd also learn, is how much difference the holes make.
To provide a more fair report, you'd need to tape over or some method to cover the 3 large holes you put in your new shroud, since that's a personal mod in addition to the Halltech CAI. The good thing you'd also learn, is how much difference the holes make.
I believe it will be better but never as good as the vararam, I base this off of general common sense and near 50 years of racing, the 60 mph fan and a DA change could have shown the 5 rwhp on the dyno or it could have been a very small % margin of error also the bigger surface of the filter even without the fan, a good tuner tunes the timing with iat's and that could net 5 rwhp, also the vararam is like an old time functional hood scoop, I have tried them on many race cars and race trucks from 2" height to 18" height single to double carb low rise to tunnel ram and it always netted better et, even foamed to hood for perfect seal and left open against the hood for starting line volume on smaller scoops, sealed always worked best, I have no experience or data in road racing. other then spirited driving with high stall converter 373 gears and higher rwhp and an EWP would be harder on engine and oil temps at those higher rpm 5800-7200 and i havnt seen any high temps because of the vararam that is sandwiched tightly to my 12x12 trans cooler dead center of my ac rad
The only thing the tuner changed to accommodate the Halltech was the MAF scaling. So the power gains are exclusively thru the design of the filter itself.
Jim Hall actually told me to trim the fan shroud although he later told me that he would have preferred it done in a different place. By my eyes, that front cowl empty space, while leaky, couldn't really provide uninterrupted airflow to a 500 hp engine at full honk. I'll be running the car with the holes drilled, so I have no intention of taping them up.
There was a tremendous amount of heat just in the intake piping yesterday. Touching the CF intake tube yesterday was really warm. On a previous car I insulated the intake tube and was able to lower IATs when in heavy traffic. But I won't do that on this car for 2 reasons: my vented hood is already lightly in contact with the Halltech intake tube and also the CF just looks good!
I can appreciate Dennis' position of form over function and I was the exact same way when I road-raced motorcycles. But I didn't just buy my Vette just because it's fast, I also bought it because it's a work of art!
OT: Dedicated tried altering the tune in my car to create a redline of only 5500 rpm when in neutral but when I tried it out I'd get a small delay where I needed full power but the car still thought it was in neutral and I'd get this small but noticeable lag under redline upshifts. Any suggestions?
I believe it will be better but never as good as the vararam, I base this off of general common sense and near 50 years of racing, the 60 mph fan and a DA change could have shown the 5 rwhp on the dyno or it could have been a very small % margin of error also the bigger surface of the filter even without the fan, a good tuner tunes the timing with iat's and that could net 5 rwhp, also the vararam is like an old time functional hood scoop, I have tried them on many race cars and race trucks from 2" height to 18" height single to double carb low rise to tunnel ram and it always netted better et, even foamed to hood for perfect seal and left open against the hood for starting line volume on smaller scoops, sealed always worked best, I have no experience or data in road racing. other then spirited driving with high stall converter 373 gears and higher rwhp and an EWP would be harder on engine and oil temps at those higher rpm 5800-7200 and i havnt seen any high temps because of the vararam that is sandwiched tightly to my 12x12 trans cooler dead center of my ac rad
Damn Dennis, you are getting old. wait a minute, I must be getting old too.
Did you move yet?
Last edited by GARY2004Z06; 02-12-2016 at 10:40 AM.
The only thing the tuner changed to accommodate the Halltech was the MAF scaling. So the power gains are exclusively thru the design of the filter itself.
Jim Hall actually told me to trim the fan shroud although he later told me that he would have preferred it done in a different place. By my eyes, that front cowl empty space, while leaky, couldn't really provide uninterrupted airflow to a 500 hp engine at full honk. I'll be running the car with the holes drilled, so I have no intention of taping them up.
There was a tremendous amount of heat just in the intake piping yesterday. Touching the CF intake tube yesterday was really warm. On a previous car I insulated the intake tube and was able to lower IATs when in heavy traffic. But I won't do that on this car for 2 reasons: my vented hood is already lightly in contact with the Halltech intake tube and also the CF just looks good!
I can appreciate Dennis' position of form over function and I was the exact same way when I road-raced motorcycles. But I didn't just buy my Vette just because it's fast, I also bought it because it's a work of art!
OT: Dedicated tried altering the tune in my car to create a redline of only 5500 rpm when in neutral but when I tried it out I'd get a small delay where I needed full power but the car still thought it was in neutral and I'd get this small but noticeable lag under redline upshifts. Any suggestions?
Wow! The vented hood sure puts a different perspective on this whole discussion.
BTW, Art never worked on the C6, but since he was on the Camaro design team and got promoted to the C7 team, that's reason the taillights got changed. Not a true story.
Wow! The vented hood sure puts a different perspective on this whole discussion.
BTW, Art never worked on the C6, but since he was on the Camaro design team and got promoted to the C7 team, that's reason the taillights got changed. Not a true story.
Heck yes the vented hood does change the math! Heck I'd use foam like in the old days and seal the hall tech cover to the vents and cut the holes in it to the outside! Now that would be a very effective cool air intake.
We need someone with a unmolested hall tech to do the testing, but I think even with Sun's well modded Halltech, we got the answer we need, the Vararam is the best if you want the coolest possible intake air.
Damn Dennis, you are getting old. wait a minute, I must be getting old too.
Did you move yet?
i am old not as old as Tom though or Tommyd my wife tells me to grow up but you are only as old as you feel, and I feel old, but going fast makes me feel young, Gary you must feel real young
Heck yes the vented hood does change the math! Heck I'd use foam like in the old days and seal the hall tech cover to the vents and cut the holes in it to the outside! Now that would be a very effective cool air intake.
We need someone with a unmolested hall tech to do the testing, but I think even with Sun's well modded Halltech, we got the answer we need, the Vararam is the best if you want the coolest possible intake air.
i was just out 2 days ago racing around with a friend, i let the car idle for about 20 minutes after we were done, popped the hood to show him and told him to touch the fast intake put your hand on it, it was ice cold, you could even put your hands on the valve covers, it was idling 181 and about 30* outside
Did some reading and from what I learned this mod will not work on a z51 ls3? Is this true?
I read that the blade maf of the ls3 can cause surging with the non laminar air flow, you could try it and see, cheap to try. Not going to hurt to try.
I read that the blade maf of the ls3 can cause surging with the non laminar air flow, you could try it and see, cheap to try. Not going to hurt to try.
Hitachi MAF on LS3 much more sensitive to turbulent air flow through the filter--stock or aftermarket. Tried the shroud prop and got surging on my '13--never had that problem on my '06 with shroud propped 3". Not bad, but noticeable. Put Halltech 105S--MAF forward design, in, opened the shroud a bit, with Intune. BAD lean condition, threw codes. Closed up the shroud opening by half, surging/lean condition went away. The Intune leans the engine, Halltech does the same--'under reports' air flow, I believe. Using them both means you really have to be careful of turbulent air to the middle of the filter. Getting it on the outside--pass side already has an opening by the airbag sensor, open the driver side maybe 2", and you get outside air in which is what you want. But, needs a delicate balance. Jim Hall quite strong on keeping turbulent air away from the filter middle, but openings on the outside are fine and create a CAI effect. Along with the Beehive cover, definitely cools the IAT when the car is underway.
I figured it wouldn't make a difference since the middle of the filter is completely blocked off. On my Halltech filter air can only be sucked in from the sides.
I was told the z51 cars wouldn't work due to the oil cooler lines being in the way.
I just want to add that out of the 3 holes I drilled, none of the 3 shoot straight air at the element. Even the one in the center is forward of the rubber end piece on the end of the element.
91 degrees today, IAT after 25 minutes in very slow traffic was running 147 degrees.
I have a gauge that shows if any timing has been pulled and it says "0". The car feels exactly the same power wise which is something I could NOT say about other cars when they sat in TX traffic.
My E85 flex fuel conversion only gained 13 rwhp when dynoed during the winter but I can't help but feel that the hp that isn't lost due to much hotter IATs is much higher than 13 rwhp. That the flex fuel allows me to keep my timing even as temps climb.
02-12-2016, 01:30 AM
also the bigger surface of the filter even without the fan, a good tuner tunes the timing with iat's and that could net 5 rwhp, also the vararam is like an old time functional hood scoop, I have tried them on many race cars and race trucks from 2" height to 18" height single to double carb low rise to tunnel ram and it always netted better et, even foamed to hood for perfect seal and left open against the hood for starting line volume on smaller scoops, sealed always worked best, I have no experience or data in road racing. other then spirited driving with high stall converter 373 gears and higher rwhp and an EWP would be harder on engine and oil temps at those higher rpm 5800-7200 and i havnt seen any high temps because of the vararam that is sandwiched tightly to my 12x12 trans cooler dead center of my ac rad
wait a minute, I must be getting old too. 
but you are only as old as you feel, and I feel old, but going fast makes me feel young, Gary you must feel real young
