First, ZZP had 3 different designs of the HV insert (hence HV3 is the most current). Some people have sold HV2's claiming they are HV3s.

Second, when I first got my hands on an HV3, I got it used from a guy locally. Before I installed it I realized, I think I made a mistake (the local guy has a Series III, which has an aluminum upper intake). I contacted ZZP, with a picture they confirmed I had a Series III HV3. I suspect because the one I had was red and the correct one I got from them later on a Black Friday discount was red. What color was yours?

Third, is you UIM the original GM UIM? I've heard rumor that if you have a Dorman or APN UIM the HV3 will not fit snuggly.

Like Chibi, I had zero issues popping mine in. Fit like a glove.

As for lose of low end power, it could be the combination of mods you are running. Not all parts work equally (you may have something working against it or need something else to optimize it's effectiveness). I think Chibi and I are in the same boat, when we put ours in our cars, we did a host of other mods. I already had a 2.5 ZZP stainless DP and high flow cat and L67 coils. When I added my HV3, I also added a port matched LIM, L67 throttle body, ER rockers and a PLOG.

I believe the HV3 was created to work best with ER Rockers and the stage 1 ZZP HV Throttle Body (I cheated modding an L67 throttlebody).

Since you plan a top swap, it would be silly to vest the time and money in the other mods unless you found a deal on them.

 

the HV3 i got was black. the member i got it said it came off his l36. as for the origin of my Upper intake i dont know for sure... as i got the engine from Morad when i did my swap but from the pics i have seen of the dorman UIM this is not a dorman.

as for the effect of my other mods... they were on the car since i first started the 3800 after the swap. i know it is said that the HV3 works best with ER rockers and other mods, but has anyone done the ER rockers and then later add the HV3 and note the differences?

I never planed on getting the HV3 as a favor the memeber sold the HV3 to me for the cost of shipping. deff couldnt pass it up. he also mentioned that he had set one of the l36 records with that exact insert.


the bottom line is it seems to add power where you rarely take the car and loose it where you use the car most.

i think i may end up installing my 1.8 SLP rockers on my L36 in the next month or so... i want to take my time and get things perfect when the topswap goes on so in the mean time gonna give it a try...

 

yeah i just installed mine its not a perfect fit like the runners but i guess i got mine in there even and flat enough. i didnt to have cut to fit into the dorman Uim it just seemed a bit uneven setting it in there.