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HybridZ

To turbo or not to turbo that is the question Opinions please.


76s30

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ok I can go back to FI tubo and go against everything I normaly do in the name of budget and hp.

I'm an N/A guy at heart I love the sound of a engine winding out,and open TB's .

the way things are going right now I've got two basic plans laid out that I can accomplish in the desired time table, both leave room for future mods (which is always a must in my book) and have about the same end cost and hp level.

 

Option 1

turbo the l20a I have already use a different head for lower compression or a thicker gasket (not sure on this cuzz a l20 bore head gasket might be hard to come by) run a standalone and a t3 for now. expected power goal 225-235 crank.

 

 

Option 2

keep the carb, cam and header I have, get an l28 a "good" head run 10:1 comp . expected power goal 210-215 crank

 

edited

Option 3 install my 5mgtte with stand-alone (this cost the least but I'm kinda a purist)

this has much mor hp potenal at the same cost since i already have it

 

 

only reason this has even come up , was my turbo buddies working me down. Now i've owned a few turbo cars but, it felt unresposive and had a "disconnected" feel but when that turbo spooled you remebered why you bought it.

I hate deceisions like this so I beg of you help me make up my own damn mind!

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Once you have driven a Z with a decent turbo at decent boost you will forget about itb's and the n/a sound. I would do option 2 but with turbo and double the hp. I would turbo an L28 before the 5m. They are ok but no better than an L28. You sure it's a 5mgtte? I don't belive Toyota ever turboed the 5m.

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toyota never did, I did. twinturbo, built it for my celica never used it.

I've already got alot of money in the 5m.I set it up with two 14b's

I put oil squirters in the block,je forged pistons , and 7mgte rods and crank, yes this makes it a 6mge.

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toyota never did, I did. twinturbo, built it for my celica never used it.

I've already got alot of money in the 5m.I set it up with two 14b's

I put oil squirters in the block,je forged pistons , and 7mgte rods and crank, yes this makes it a 6mge.

 

 

This is hybridZ. That 5m sounds pretty sweet, so my vote is for that. You also score some major originality points.

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Considering option #2, consider the responsiveness of the engine below 3500 rpm before the cam starts working.

 

Why doesn't anybody complain abbout 'camshaft lag' in this case, yet 'boost threshold' is some sort of terrrible bugaboo...

 

You hit it on the head indirectly: because the power is so non-linear. When you hit boost threshold (and on a T3 it will more likely be 2500...) the power is so much more than an N/A's linear delivery.

 

The conclusion: the engine is being driven wrong. If you keep a turbo on the boil, same as a cammed engine in an N/A you end up with none of the 'non-responsiveness' that uninitiated drivers feel when driving a turbo in a lazy manner, below boost threshold two gears too high for the speed being driven.

 

The thing is on a turbo car it's easy to drive that way because of the torque available whereas the N/A will be a miserable, boggy dog till you get up on the cam.

 

Camming and flowing a Turbo car will result in power that pulls easily into the 7000+ rpm range on an L-Engine. It's just most take the lazy way out and boost a stock engine---and as a result end up with something that barely revs above 5500-6000 due to camshaft limitations.

 

Use the right cam in the turbo application, and your turbo masks the cam's inefficiencies below 3500 by adding massive torque compared to an N/A of even 10:1 cr, and when you come on the cam at 3500 the feeling is linear progression just like an N/A setup.

 

Problem is, most people over turbo their applications so that boost threshold is above camshaft torque peak---so you have 'mismatched components' that compound a poor situation. Get it set up correctly so the turbo is boosting before you reach a camshaft peak and simply bypass excess exhaust gas at the top end for the pull to 7K+.

 

Vote for Turbo, here, obviously.

 

But if the 5M is cheaper, and you already have it....logic dictates that is the way to go. Who cares what provides the motive power, just so long as it goes? It's a flattish Valvecover, grind it off and put some stick-on Nissan decals on it and get people thinking...

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update

A z friend stoped by yesterday, ofered a l28 and n42 head for a very good price. right now I want it running so I'm gonna put this one together and run it. In the mean time I can put together a turbo motor. For now at least the car will be running/ driving.

 

I just didn't feal right puting a 5m in a Fairlday. If it was an A-spec, I would have done it already.

 

Thanks for the advise.

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