Bumpin nailed it. The w-body store kit is not anything new at all. I've seen it there for years now and have used it as a source for what all is needed for a top swap (although I haven't done a top swap on my car). I did swap the heads off of my car with the help of a friend of mine and to be honest, it's really not that hard of a job to do surprisingly. If you have little experience in doing this, just make sure that you have a source that will help you along the way.

Also, a good torque wrench is your new best friend when you do a top swap.

 

Well now that I know a few more things about both kits I have one final question. Which kit do you think will leave me hanging with the fewest problems? I want this thing to be installed without a hitch, with no problems after the install.

I've read the SSM90 kit uses the accessory belt to drive the supercharger, where the the L67 topswap uses two belts. Somehow people say a two belt system is better, I'm not sure I understand how. I've also read the SSM90 kit gives people problems on running their cars afterwards i.e. start up problems and idle problems. I know that HP and TQ posted gains are not very accurate, but ZZP advertises a 60HP and 60TQ increase, where WBstore advertises a 45HP and 50TQ increase. Think anything of this?

Lastly, I will not be installing the kit myself, as I have very limited mechanical knowledge, not enough to rip things apart and find out how they go in, so I will be paying a professional to install it, it's just a matter of finding someone knowledgable enough with 3800 engines and supercharges. Should I go with the SSM90 or L67 Toswap based on this?

 

Honestly, with little mechanical knowledge, you could most likely install the SS kit. All you have to do is unplug the battery, remove the injectors, serpentine belt, the UIM, probably change the MAP sensor, remove the LIM. Then just bolt the new LIM & blower up, reinstall the injectors, set up the vacuum lines and replace your PCM (literally a ten minute job with my Monte). Hell, I knew nearly nothing about motor work before I messed with my 3800, and as we speak I have already taken this motor apart and put it back together, and now it's sitting with no heads on it. Just waiting to get them back and have a nice valve job done on them.

 

A ten minute job? And ZZP charges $400 for an install on a ten minute job? You can't forget the MS90 kit requires new fuel rails to be put in and a modified intake manifold. I think from even an experienced mechanic that this job would take several hours...this car is my daily driver, I don't want anything messed up.

 

unless you plan on running below 3.1 pulley, the m90 kit from zzp is fine. remember, the 3.5 SS pulley is the same as running a 3.1 on a stock L67....higher compression. im only on a 3.8 ss pulley and im seeing about 8 LB of boost.
IMO, the kit is great. the customer service was above average but not exceptional.
most importantly, everything fit as it should and the car runs great minus the cold start issue, but some have corrected this by making the car run rich until closed loop. performance wise, it has 0 effect.

 

That's one the only thing that concerns me about the ZZP kit...the cold start issue? Have you been able to fix it?

Also, the Wbody L67 top swap kit comes with a 3.8 pulley, that seems awfully small considering the higher compression of the L36 engine, I'm hoping I can run a 4.0 pulley with the top swap, because I want 0KR, if I go that route. Is that possible?

 

I was referring to the PCM being a ten minute job. Taking the motor down to the heads, then reinstalling the LIM, blower, etc can be done in ~4 hours.

 

My first time (doing the rockers / hv3 / plog etc) took me 6 hours to tear it down and back.

 

Impossible to say either way, both has its pros/cons. The ZZP kit uses some aftermarket parts (like their fuel rails that had problems with bad regulators in the recent past)- whereas the top swap uses all OEM parts.

The ZZP kit requires less work, so there is less potential for stuff to be screwed up due to installer error.

However, depending how much mileage you have, replacing the head gaskets in doing a full top swap may be good preventative maintenance for the future.

I don't think either has much advantage here.


Better belt wrap (plus the option to run an 8 rib belt for more grip)- and much cheaper pullies (also many more sizes). You've got to figure also that GM made 2 separate belts for a reason; they could've just as easily put the supercharger on the same belt with all the accessories as well.

I wouldn't pay attention to either. Just doing stock swaps on both, the ZZP kit should make more power- doing an otherwise stock top swap with a 3.8" pulley is like running a 3.4" pulley on an L67 with no other mods, it will have knock, and make less power (hence why people suggest doing some other cheap bolt ons while doing a top swap-especially since you're saving a lot of money by doing it). Also, doesn't ZZP do a port job on the blower too for the SS kit? My point is, given equal pulley sizes and equal mods, both should make almost identical power.

Thats tough, for a normal mechanic, it would probably work out about the same. For the top swap, they'd be basically stripping the car down to the short block and putting OEM parts back on. For the ZZP kit, they're installing 'aftermarket parts' (for which they normally charge more to do in case stuff goes wrong due to the aftermarket parts).

For someone in the 3800 community, the ZZP kit should be cheaper to install.

If you do supporting mods (which you could easily afford given the big price difference between the two setups)- the 3.8" pulley would be well within reach for you.

 

" ...doing an otherwise stock top swap with a 3.8" pulley is like running a 3.4" pulley on an L67 with no other mods, it will have knock, and make less power (hence why people suggest doing some other cheap bolt ons while doing a top swap ..."

I don't mean to Hijack the thread but what kind of mods would help avoid/minimize the knock?