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sr20det swap


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Since they are still trendy, they are still decently pricey regardless of condition.


As for install, it will likely take the same work a 240sx KA engine would take. I would start by researching that some, as I believe it's more common in 720s than SRs.


Basic issues I expect you will run in to:


Modify engine mounts

Front sump engine, rear sump likely needed

Transmission mount may be custom, but then again may bolt in fine.


Physically, it will likely clear everywhere but the oil pan, but it's possible you will have turbo clearance issues with the brake booster.

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All RWD SRs are imported from Japan so there aren't any just laying around in wrecking yards or back yards. Any SR for sale I would be suspicious of as it's probably been abused to shit. As stated, parts for it won't be found at NAPA or cheap. Your best bet is to save up and go to a shop that specializes in low mileage imports that will have some kind of warranty. You will need the transmission and all the EFI wiring for it too. If you do the work probably 4-5K will do it.


An SR20DET in a 720 is like using a race horse to pull a semi trailer.  I would go will a larger displacement VG30 or 33 from a domestic vehicle, something with way more shove at low RPMs.

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An SR20DET in a 720 is like using a race horse to pull a semi trailer.  I would go will a larger displacement VG30 or 33 from a domestic vehicle, something with way more shove at low RPMs.

What? Not that I think the OP is going to follow through with this swap. But, I think your analogy is way off. My 720 weighs the same as my S14, despite lightening mods done to the S14.

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It's just opinion.


Small displacement turbo engines are only fun when revved up. Or swapped into in a smaller light car.


Larger displacement engines pull hard right from the start, will do it all day and last forever.


99.999% of driving is at low speeds.

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This debate is a good one - torque vs hp. It is an old debate too.


You guys should all read the story of the development of the GM Vortec LS V8. At the time, GM was considering dropping the pushrod V8 completely and focusing it's efforts on the multi-valve, multi-cam arrangements. Two guys, on their own time, started the development of the LS to get it to the point where it could be mocked up. They then convinced GM to fund the prototypes. When working prototypes were ready to go, they put one in a ZR1 Corvette and put it alonside a stock ZR1 Corvette. They had GM execs run the cars at Willow Springs raceway without telling them which was which.


The results were unpredictable as the majority felt that the ZR1 (LT5) was more fun to drive, but they all agreed that the torque of the LS was actually a faster package.


Moral of the story - sometimes, we just want to feel the punch of the turbo kicking in, even though the torque of a N/A engine may actually be the better choice.

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Torque is what gets the job done. Period. Torque is a twisting force. HP is a mathematical  calculation using torque and RPMs. They are not the same but indicate each other. If you have torque and RPM you can work out the HP. If you have HP and the RPMs you can calculate the torque. There is no way to measure HP directly only calculate it. Torque = HP X 5252 / RPMs. HP = T X RPM / 5252


The more HP you have, the more torque you have. You could say that HP gets the job done but as the HP is derived from the torque so it's better to just say torque.


Torque is always higher than HP below 5,252 RPMs

HP is always higher than torque above 5,252 RPMs.

HP and torque are always the same at 5,252 RPMs.


100 HP at 5,252 RPMs... solve for torque using Torque = HP X 5252 / RPMs 100 X 5252 / 5252= 525200 / 5252 = 100 ft lbs.


If your torque remains constant (flat) your HP will double every time the RPMs double.  Example 200 HP at 3K will be 400 HP at 6K, will be 800 at 12K.



The Z24 makes 130 ft lb at 2,800 RPMs what's the HP at 2,800? HP = T X RPM / 5252 or 130 X 2800 / 5252= 364000 / 5252 = 69.3 HP. ANY engine that makes 69.3 HP at 2,800 RPMs has 130 ft lbs of torque.

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As the owner of a Pathfinder with the vg30 in it, it's a way better truck engine. Good low end grunt, plus Turbo parts can be adapted from a Z31. Find a later one with the round tooth timing gears and you're set.


Pulls the heavier Pathfinder around really nicely. But it does have 4.375s rather than the 4.11s in my pickup.

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