Thread: HV3 Questions

I'll agree that the high-rpm 30hp gain on a lightly modded test car should be more clearly labeled in the sales page, but thankfully the test details don't hide this, giving a paragraph called "Test Setup" to point this out.

"The test GT had various modifications that could be considered recommended complements to the HV Intake Insert. These included ZZP ER High Ratio Rockers, ZZP Stage 1 HV Throttle Body, an EPP Cold Air Induction, U-Bend removed from exhaust system, a 2 1/4" off-road downpipe and a 180ºF Thermostat. While all of these modifications are not required, they do enable the L36 to run at higher RPM with the stock camshaft. Without these modifications, the true potential of the ZZP HV insert would likely not be fully realized. If an aftermarket camshaft were used, equal or greater gains may be possible with the ZZP HV insert over the stock setup."

Also, this test was done a LONG time ago, during the introduction of the 1st HVII design. Supposedly the current HV3 "has slightly longer runners to give more HP and torque in all usable rpms!"

I'd also like to see a test comparison with less supporting mods to maximize a difference, using the new piece. Unfortunately, just as we saw 8-10yrs ago with the original tests/claims for things like TOG & SLP headers, and other performance items... some were done straight-up, with no factors that seem to dispute the numbers, others were references to potential gains with no clear description of how to get there.

Myself, testing the 1st set of SSAC (DPP) headers 4yrs ago, also clarified the amount of mods I had at the time, while seeing a 24+whp gain (XP, Gen3 topswapped L36 block, 3.3" pulley, intake, 2.5" catback, DHP). Wasn't a perfect test for stock-stock obviously, but very few people in the loop at the time had quick access to a dyno for multiple visits, funds to accomplish it in a timely manner, and ability to install quickly without knowing what issues might arise on the prototype.

An HV3 is a part that an ambitious buyer would be able to install or remove on the spot, when the car is cooled of between runs, if they wanted to provide the community with some back-to-back stock examples, before adding additional work, if they choose. I don't personally own an L36/L26 car, and I'm not sure if the last 2 locals who I haven't top-swapped (yet), would be willing to drop the dyno coin if/when they want to get an HV3.

- Dave

Hell, magnaflow claims you'll gain 12 hp from a catback on our cars.

http://www.magnaflow.com/02product/d...rixgxp3.8L.jpg

I'm not so sure...

Honestly though, HV3 makes a nice modest mod but if you compare the cost of an HV3 + rockers/cam you might as well go top swap if you're looking for the most bang for your buck.

Originally Posted by matt5112

Hell, magnaflow claims you'll gain 12 hp from a catback on our cars.

http://www.magnaflow.com/02product/d...rixgxp3.8L.jpg

I'm not so sure...

Honestly though, HV3 makes a nice modest mod but if you compare the cost of an HV3 + rockers/cam you might as well go top swap if you're looking for the most bang for your buck.

I can possibly believe that claim, and only for one reason... I was interning at Corsa in '03 when they were starting to work on a W-body exhaust. I did the Pro/E models & test fitting for a few that went on some Coke 600 and Brickyard 400 pace cars, then dyno'd one on an L36 Monte for an 11whp gain (152 to 163). I can see something pushing another 40bhp stock getting 1-2 more gained from opening the exhaust flow.

Yes, the HV3 is a good mod, and even though butt-dyno's are worthless, it seemingly can be felt from the stock Monte I put one in (I didn't feel much for the gains from headers, FWIW).

The top-swap is another level of spending/modding that some folks just aren't willing to jump to. The cost of a modded N/A setup starts approaching the top-swap cost quickly, without getting near the power potential, of course. The difference comes with work and such involved, and the snowball effect of spending once you're past that point.

- Dave