yeah exactly. I mean there are good points to either side of the swap debate, but I think I would just get either a newer car w/less miles or just do an L67 swap all together.

 

Anyone know the actual weight difference between a LS4 and an L67? I bet the difference really isn't all that big- nothing that a little front end weight reduction and putting the battery in the trunk wouldn't fix.

But the L67 is an iron block, iron head engine- and that blower weighs a good bit. The LS4 is aluminum block, aluminum heads with a composite intake manifold- I bet the weights really aren't all that different.

I still wouldn't do it myself- mostly because of the huge price difference and a lot bigger pain to install.


Can you please elaborate on what is dangerous about a top swap? Also how they are potentially costly as well.

The only way I could see it being costly is if you break something during install (in which case you shouldn't be swapping engines either) or if you chip a piston from not having enough support mods for the pulley (in which case you're an idiot for not scanning and running too small a pulley for your mods- a 4.2" pulley is needed for a stock L36 to run mostly without knock).

You'd be suprised how little difference there is between an L36 and L67- the only major difference is compression ratio. If you're worried about the L36 not being strong enough- you have to consider that many of the high end M90 guys that are maxing their blower are upgrading their bottom end TO an L36 to make more power. If it works well enough for these guys running 11s or so, I'm sure it'll be just fine for a 13/14 second daily driver all day long.

The biggest thing is making sure your tune is sound and that you have no knock- but thats just as true for an L67.

 

I've just seen too many guys do top swaps and scatter their motor. They throw a S/C on and upgrade their TB and set boost @ 11 psi and scatter it. That's why I am leary about it. I know it works if you use modest boost.

 

The piston, wrist pin and connecting rod are what differ between a normally aspirated 3800 (L36) and the supercharged short block (L67), as the supercharged ones are much heavier and stronger.

The resulting compression ratio subsequently differs between the L36 (9.4:1) and the L67 (8.5:1)

That's right, you can't just bolt a blower on a naturally aspirated 3800 and expect to get a L67! Heads, rods, and pistons (including wrist pins) need to be changed.

 

wow guys thanks for all the info. i have made a decision and decided to go ahead and do a top end swap now all that is needed is the cash which will be flowing in, in about 2-3 weeks so ill keep you guys updated and ill see if i can post up some pictures of my monte so you all can see what im working with haha

 

Good choice. If I wasn't going turbo this summer a top swap would definately be my choice...

Good luck and keep us updated.

 

My fellow monte carlo lovers i think i have seen the end of my L32 becuase today while doing some drive by shots of my car kinda went over board and when i finished my car started acting up engine started to kinda back fire and wanting to turn off so i think this is the end of my L32 and i think ima get the S/C engine gezz wut luck of mine dont you think first are my valves and now i got no clue whats up with my car now.... damn it

 

I'm pretty sure you mean L36, but that really sucks man.[:@]

 

There are only 2 ways that can happen:

installer error or an ignorant owner.

The engine can get destroyed by someone trying to do the install and goofing it up (ie getting coolant into the oil, etc)- then that is the owners fault for not having a reputable shop do it if they cannot do it themselves.

If by 'scattering the engine' you're talking about chipped pistons- thats 100% the owner/drivers fault. Pistons simply will not chip with proper air fuel ratio an no knock- especially not on stock power. There are too many idiots who slap an L67 top end on and never scan despite everyone telling them to. IMO, if you want to mod a boosted 3800- you need to have access to a scan tool, or must buy one. You can buy an aeroforce scan tool gauge for like $200, there simply is no excuse to cheap out and not buy one to monitor knock.


That exact scenario is no different if someone swapped a whole L67. You can't change boost without changing pulleys. You shouldn't swap pullies without supporting mods and scanning for knock. If someone acts like an idiot and slaps a 3.4/3.5 pulley (about 11 psi) on their L36 with a top swap and blows pistons- the EXACT same thing will happen on an L67, its no different.

You just really have to be smart about modding when doing stuff like that- and monitoring knock is the only smart way to increase boost (either from dropping pulley size on an L67 or adding a top swap).

IMO, I'd probably find out what exactly is wrong with it first. If you have the ability to do a top swap or swap entire engines, you should be able to easily diagnose problems with the car. I'd just hate to see you scrap an engine because of a fixable failure. You have to think- if you do a top swap, the only real part of your stock engine left is the short block- as long as your crank, pistons, cam/timing chain are ok- everything above that gets replaced.

From what I have seen- no one has ever broken an L67 OR L36 wrist pin or piston from too much power. Just because the L67 has slightly beefier wrist pins doesn't mean that it won't be perfectly fine with tons of power. I would have a much different opinion if he was talking about building a 600+ whp turbo car, but he's looking at a sub 400, probably sub 300 whp car- which is well within the realm of a stock L36 piston/connecting rod.

Also, you don't necessarily want the lower compression of the L36 with the blower- if you get into modding the engine further- it will help you to keep the blower in a more efficient range- making more power with less money.

 

Hey guys does SEA FOAM creat prob. for the engine? cuz i used it and it didnt blow smoke when i did it it gradually started smoking stoped and smoked everytime i turned the car on..... do you think thats what is affecting my engine..