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Which engine swap would be better suited for a turbo setup? KL-DE or KL-ZE? I'm sure there are some ZE's that have been turbocharged but which one would be less complicated and would require less modifications?

Completely depends on your budget and horse power goals. The DE has lower compression stock and will handle more boost out of the gate. You should be able to hit 15-17 psi of boost, properly tuned, on stock internals.

The ZE has the potential to make the most power.. but you will have to spend some serious cash to beef up the bottom end if you want to run more than 5-7 psi of boost.

Tunes67

Do you know what is the most horsepower that ever came out of the DE??? turbo??

Not really.. I havent seen any dyno sheets of one so I wouldnt want to speculate on the actual numbers. Try asking in the Forced Induction forum. Those guys will have a better idea of the potential power of either setup.

Tunes67

Hey Tunes67 why is lower compression better for turbo?

is to allow excessive boosted air escape through piston rings??

Lower compression isnt neccessarily better for boost. Think of it as 2 glasses of different size. One bigger than the other. The lower the compression ratio of the cylinder.. the more room there is in the cylinder to cram more air into it. Just like two different sized glasses.. the bigger glass will hold more water than the smaller glass. That is why the DE will hold more boost stock than the ZE. But neither engine was ever designed for boost.

Now.. if you have an extremely stong bottom end.. rods, pistons, rings, crank.. etc.. the more power it can withstand.. which means you can force even more air into the combustion chamber. This in turn will allow you to make even more power.. but if the bottom end of the engine isnt strong enough to handle the power.. all you have is a messy bomb waiting to happen.

This is a very simplistic explanation.. for more information of Turbos or boosting.. I recommend you find, buy & read Corky Bell's book entitled "Maximum Boost"

Tunes67

Do you mean that compression is the free space between piston and cilinder head when piston is on top?

I thought it was the strengh of pistons rings... but now it makes more sense. Thanks

Yes, the "compression" really occurs between the piston top and the cylinder head.. the rings just prevent leaks more or less. When the piston reaches top dead center and the air/fuel is completely compressed into that little space.. the space is referred to as the "Combustion Chamber" Since its at this point that the spark plug ignites the mixture and forces the piston back down.

Tunes67

the only actual dyno results ive seen for turbo'd 2.5's was a KLZE im not sure how much boost or what was doine internally, it looked verry well done and quite expensive and it pushed 290 at the wheels. honestly i dont think any of our cars need anymore then that lol.

LOL ok to clarify a few things...

1: 10:1 compression vs 9.2:1 compression
a ZE running 10PSI would have a compression ratio of 16.8:1
a DE running 10PSI would have a compression ratio of 15.45:1
Conclusion: A DE would have to run more boost to make the same power...

2: ZE Heads and IM vs DE heads and IM
Flow Flow Flow... ZE heads and IM flow far better

3: Amount Of Boost...
No one and I REPEAT NO ONE HAS EVER BLOWN A KL ZE/DE RUNNING TO MUCH BOOST... The only problem people have is with the A/F mixture, and they end up burning up the motor...

4: Internals
The ZE/DE have the exact same internals mines the pistons... (DE dished making the lower compression) other than that there the same...
Thus you could run the exact same amount of boost on both...

5: F/I Info
Ok theres several things to consider when running a turbo..
First A ZE can only run 6-7 PSI before you have to seriously consider some fuel management... Even running 6-7 PSI u are going to have to Change injectors, Fuel Pump, and FPR...
Your best bet is to prosue Mega squirt even if your only running a few PSI
With MS, Upgraded Injectors, and upgraded Fuel Pump you should be able to get around 400 HP out of a ze... if not more.
Read F/I forums and talk to those people.

One last upgrade would be to have your cams ground, and to do some porting on your heads, along with upgraded valve springs and retainers.

MazdaNoob123 wrote:LOL ok to clarify a few things...

1: 10:1 compression vs 9.2:1 compression
a ZE running 10PSI would have a compression ratio of 16.8:1
a DE running 10PSI would have a compression ratio of 15.45:1
Conclusion: A DE would have to run more boost to make the same power...

2: ZE Heads and IM vs DE heads and IM
Flow Flow Flow... ZE heads and IM flow far better

3: Amount Of Boost...
No one and I REPEAT NO ONE HAS EVER BLOWN A KL ZE/DE RUNNING TO MUCH BOOST... The only problem people have is with the A/F mixture, and they end up burning up the motor...

4: Internals
The ZE/DE have the exact same internals mines the pistons... (DE dished making the lower compression) other than that there the same...
Thus you could run the exact same amount of boost on both...

5: F/I Info
Ok theres several things to consider when running a turbo..
First A ZE can only run 6-7 PSI before you have to seriously consider some fuel management... Even running 6-7 PSI u are going to have to Change injectors, Fuel Pump, and FPR...
Your best bet is to prosue Mega squirt even if your only running a few PSI
With MS, Upgraded Injectors, and upgraded Fuel Pump you should be able to get around 400 HP out of a ze... if not more.
Read F/I forums and talk to those people.

One last upgrade would be to have your cams ground, and to do some porting on your heads, along with upgraded valve springs and retainers.

I'm sorry but that 400hp estimate is not correct. To reach 400hp on a ZE is not easy...let alone possible on stock internals if you want it to last more than a day. You would need forged pistons etc. to even get close to that number.

ok im quoting things ive heard from members that have turboed there ZE's
(Babyblue) and read some of the info on the ZE/DE
everything ive read says Stock internals = fine... Yes 400WHP is probably gonna start eatting parts, as u are probably pre detting the motor,
with some higher octane, or a better IC you could probably get there on good 92 pump gas, but i beleive it is risky...