donbrew

And try scrolling through threads.

Steve Gilbert

When i said pulley on turno meant harmonic balancer

firemangeorge

Why a smaller pulley on the balancer ? Not seeing any reason or benefit for this.

Steve Gilbert

Your fan belt robs hp. I put smaller pulleys on a pick up truck i had gained 10 hp on the dyno

firemangeorge

Maybe it did on a pickup but not going to do much for the SS setup. The belt doesn't run a fan on the SS like on the pickup. That's where you probably gained HP with the pickup.
Also, going to a smaller pulley will slow the rotation speed of the alternator. Not advisable because the HHR electrical system is very finicky. Best to leave the stock diameter pulley in place.

Steve Gilbert

Thanks for advise
Do i need to get the gm tune first or can any can tune work. Also i asume the sensotd have to be changed

DrLoch

WOW FMG you beat me to the enter key....

Honestly the smaller pulley isn't going to add much if any power, you could actually be shooting yourself in the foot since these car are very sensitive to voltage/charging variations. Most everyone I know of in the LNF community doesn't/hasn't messed with slowing down the accessory belt as a means of adding power.

A tune by someone who is experienced with an LNF with no other bolt on's is a major step in the right direction. There are a lot of tuners out there but most don't have experience tuning a LNF. If tuned incorrectly you can and will hurt them.

Then look at post 36 of this thread https://www.chevyhhr.net/forums/hhr-...e4/#post795420

2005HHRauto has defiantly figured out what is the best bang for the buck

Steve Gilbert

what can an un touched hhr ss dyno at,and what can the hp be turned to with no add ons,or do you need the gm tune first

Dbeluscak

Once you finished reading doc's link, I've got another regarding the tune you will want.
https://www.chevyhhr.net/forums/hhr-...t-tuner-56002/

Hopefully from there you'll have an understanding of what our cars are capable of. Quite a bit for for 121 cu in!

RJ_RS_SS_350

2005HHRauto has been very helpful, not defiant at all!!

I know, I know, dang autocorrect!