Joe_G

^^^ Totally understand Suns! I think your observations on IAT while sitting will be a good test for those that do drag race when making their decision.

HOXXOH

But only with the caveat that the Suns test included cutting 3 large holes in the shroud.

Maybe another test for IAT comparison would be on a bone stock car with, and without, merely a propped shroud. That test could be highly controlled, since the install can be done in 10 minutes to avoid changing conditions. It could also include possible differences in ECT and even if variations existed in the size of the propped opening.

Joe_G

^^^ Tom I think the propped shroud is the best plan with an 08+ blade maf and their great intake (which has a big filter like the Halltech.

Problem is, I don't think you can do that with a Z or a Grand Sport as the front facial will not allow it. It's been a while since I looked but I think I'm correct on that...

Suns_PSD

Propped shroud???

What is that?

Joe_G

Search for toggle bolt free cold air.

Suns_PSD

I see now.

HOXXOH

Hey Joe, the toggle bolt is not a good solution. Besides my experience, I know of a couple others who have had them fall out, due to the design that doesn't allow the bolt to go through the openings on both ends.

Here's the better solution and cheaper too.
https://www.corvetteforum.com/forums...post1578067852

Joe_G

Great solution Tom!

Do you know, can this work with the Z or GS wide grill and front Fascia? They are different than the regular c6 and I seem to remember that this mod won't work with that setup... I could go investigate on my own car I guess...lol

HOXXOH

The part numbers between the base and GS are different, but I can't imagine the attachment of the shroud (GM calls it a baffle) to the front frame would be at a different location.

Did you have to buy a new shroud when you swapped to a wide body?

emoFTW

That's interesting. I'm having a hard time grasping exactly where this prop open. Anybody have any pictures of how it's used?

Joe_G

No, I didn't... but somehow if my memory serves the way the shroud attaches to the wide mouth grille doesn't allow the prop mod. I realize as I type that it doesn't make sense but it seems the regular c6 shroud uses push pins into the bumper beam but the GS/Z pushes into the bumper itself so it doesn't have the solid mount to create the gap we are talking about creating.

I'll try to get a look at it on my car, but as I recall it's hard to see. If we had a shop manual diagram I think it'd show what I mean.

sevinn

https://www.corvetteforum.com/forums...gle-bolts.html

Check that thread out, but use HOXXOHS solution instead. I'm going to be giving it a try. I did it with my stock intake and the maf wasn't happy though.

Suns_PSD

I don't have much time on the halltech, but I can tell you that cruising down the highway and at extended red lights it was two to four degrees above ambient just like the Vararam. On a warm engine, when I stopped at a gas station to fuel up the temperatures were about 17 degrees higher than ambient when I restarted the vehicle and quickly cooled down once I moved. That's either the same above ambient as a Vararam or slightly higher after parking on a hot engine.

Does anyone know how to make the intake air temperature sensor and the gauge on the HVAC unit match perfectly? Because even when I start the car dead cold they are two or three degrees apart.

sevinn

I have never had mine match even with the maf loose under an open hood.

Joe_G

The sensors are at different locations, outside air is really low on right side of shroud, maf is a foot away, one has air rushing by it, one doesn't when sitting, and there's lots of hot stuff near the maf.

They never read the same in my experience.

Suns_PSD

Oh, that is what that sensor is for down on the shroud? I thought it was related to the airbag or something.

I saw once a set of instructions for making those two air temp numbers match perfectly on a cold engine. It required you to go thru your HVAC controls I thought? Not a biggie.

Joe_G

I think there's a way to adjust the ambient sensor if it's misreading...for sure there is on my wife's Odyssey and I thought you could on the Vette as well... I could be wrong on that. Too lazy to google it. lol

flyby763

My 08 Z06 uses push pins, I replaced them last year

Joe_G

I think there is a close out panel behind the grille below the shroud which doesn't allow what we are tying to do here on a z06 or grand sport.

Suns_PSD

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.