So...my girlfriend bought a 2007 HHR, brand new with the 2.4L engine. But a little background on me: my father has been a mechanic and speed junkie all of his life and who would have thought? i followed his footsteps. I recently purchased a 2006 C6 Z51 and have been building up a little extra funds to do a L92 heads and cam package along with full exhaust (headers to catback) hoping for 480RWHP. Anyway, the girl absolutely loves the car (what can she say shes got good taste, i mean she'd have to, she picked me ) well shes been doing some research on mods to make the car a little quicker. Ive been giving her tips and what not but ultimately, the mod market for HHR's come no where close to that of vettes. So we did a little thinking, because it is a chevy and from what i see under the hood, im assuming the engine mounts would be the same or similar to other vehicles. And the million dollar question...has anyone considered installing a LS4 into an HHR? Because the LS4 are made to incorperate front wheel drive i figured it wouldnt be too big a task. (disclaimer: some assembly required) Any feedback and information would be appreciated. Constructive criticism only please, this was just an idea with no prior research.

LS4 engine for sale on Ebay

 

Don't think it will fit. Probably a different cradle, different trans, wouldn't clear the strut towers, steering gear, brake assembly, radiator, etc.

I've seen this done....BUT IT IS NOT ON A STREET DRIVEN VEHICLE. But, good luck if you procede and try.

Need to ask also......are you being realistic of your 480 RWHP expectations, on the Vette?

The engine is rated at 400 at the crank, I believe......using industry norms of a minimum of 10% (usually 15-18%) drivetrain, accessory loss..brings you to 360 RWHP. So, you're expecting something like 120HP from the changes you expressed. It must be a hell of a cam, you're thinking about.

 

This is a dyno sheet of the kit that I'm going for and the only difference is that this car had intake. The idea behind the L92 package is, once paired with an appropriate cam, the amount of flow becomes tremendous and therefore increasing horsepower and torque. But like i said, I'm hoping not 100% yet.

For 300hp...i don't think we'd really mind about the warranty.

 

Thanks for the post, it is interesting.

BUT, YOU DID NOTICE THE SPEC'S, i.e., horsepower and torque, where taken from the flywheel NOT the rear wheels. Again because of parasitic loss, it would be more like 420-440 at the rear wheels.

For example, I've witnessed Z06's on dynos. The advertised HP of 505 is more like 450-460 on the dyno.

Now understand, I'm not picking a fight here. I just think you may be a little confused with your expectations. You more than likely mean, "at the flywheel". Which is generally must greater than at the rear wheels.

Also, just noticed the "before" dyno runs. Notice the HP for the initial run is 350....50 less than the GM advertised 400 HP.....which is confusing.

 

No no, i understand I'm just trying to clarify myself. This, as per the dyno, is a 2007 M6. Therefore, it is a C6 with an LS2 factory spec'ed at 400hp 400ftlbs. If you look at the original numbers which are highlighted in yellow, it shows 351.8hp 357.2ft/lbs of torque, which are the rwhp for an average C6 with the 15-18% loss i think we all agree on. So i am assuming from what this vendor has told me that the kit is rated for RWHP in the 480's unless he can do some funky rwhp and flywheel hp mix on this one graph. But according to other articles in GMhightechperformance, these are average gains for a L92 head and cam package.

This is a dyno from LG Motorsports with their version of the L92 package
Link
And i'm almost 100% sure this is RWHP.

 

Hey I suggest we take the Vette discussion to the lounge or PM. We're high jacking YOUR thread and it is under the title of HHR General, so we should stop confusing people. Your call !!!!

But, you have my interest.

 

Hahaha, i concur...back to making a Frankenstein of an HHR. Anyone else with ideas or info?





Snoopy, definitely a conversation i enjoy. Once the car is completed ill post up the dyno graphs, hopefully it'll be done before spring.

 

Either find a wrecked LS4 car with an intact front clip and graft it on up, or have a frame shop custom build a power cradle that'll fit the HHR. I'd betcha you could get it to work, but the entire front end of the car will need to be re-engineered. You gotta keep in mind the mods that the engineers had to do to the W-car AND the LS engine to get it to fit in those cars--redoing it for the Delta platform is going to take a little more than an angle grinder and a MIG welder. The W-cars also use a magnesium engine cradle to reduce weight, so good luck welding on that too.

Big bucks, but I'd love to have one too!

 

Just my, but I think it would be easier to convert the HHR to RWD, leaving much more room up front & giving a much more balanced vehicle. The solstice/sky RWD parts are pretty bulletproof, as there are companies like Mallet doing LS series V8 conversions on these cars. Also the new caddy CTS V6 is direct injected with 300HP, that would make a sweet powertrain for an HHR I think. There were two HHR V8 conversions done in the spring of 2005, unique performance & year one both did one for chevy. Both were RWD. Just seems like if you are going to go to all of the trouble to put a V8 up front, might as well make it a nice balanced package instead of fighting torque steer and packaging issues!

 

I love the idea of a bigger engine in the HHR. Although a V8 would be kinda an over kill for the small car, I do like the sound of a V6 and think it would be a much easier instal.

You would not really have a length problem, but a width problem of the V6. I see there is room buy the front radiator mounts to play with but not much. Maybe like 4-6 in tops.

Engines like the 4.3Chevy from the S-10 or something would make this car MOVE quickly.

I have a Dodge Grand caravan for the wife. I have spun the front tires with 7 people in the van and had to let off to get them to stop. Left marks for about 20ft. It has the 3.8L in it

But Im game for a FWD or RWD either way. Make a nice "drifter" with RWD according to my son Gage.