Engine work required for 600-700TQ twin turbo setup?
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Engine work required for 600-700TQ twin turbo setup? Hello, I'm fairly new around here. I've had a '91 Nissan 240sx SE sitting in the garage for about three years now and am just finishing up all the suspension & chassis work. I'm now starting to think forward to motor setup.
I'll be driving it around 2-3 times a week only 6 months out of the year. My top priority is reliability & quick throttle response using twin turbos---one small one large. The motor I have in mind is either an LQ4 or LQ9 which I'm quite set on due to reliability concerns. The engine will be paired to a stage 5 RPM transmissions T56 Magnum.
When I drop this motor in I want to keep it in there for the next 8-10 years as I will be babying this car. However, still would like some snappy response while putting around town or driving to the lake cabin 160 odd miles east on a summer day.
What kind of work will I have to put in on a motor for it to reliably run this setup with 600-700 TQ?
I'll be driving it around 2-3 times a week only 6 months out of the year. My top priority is reliability & quick throttle response using twin turbos---one small one large. The motor I have in mind is either an LQ4 or LQ9 which I'm quite set on due to reliability concerns. The engine will be paired to a stage 5 RPM transmissions T56 Magnum.
When I drop this motor in I want to keep it in there for the next 8-10 years as I will be babying this car. However, still would like some snappy response while putting around town or driving to the lake cabin 160 odd miles east on a summer day.
What kind of work will I have to put in on a motor for it to reliably run this setup with 600-700 TQ?
One Small turbo and One large turbo is a terrible idea on these engines. A pair of billet compressor GT35s will make more than enough power if you keep the boost reasonable. They will make the car go everywhere sideways if you get goofy with the boost control. I hope that is 600-700TQ at the flywheel. Because that much at the tires.......maybe even at the flywheel.....is going to do nothing but spin the tires to oblivion in that small car.
Any 4.8, 5.3, or 6.0 will be very reliable if set up well and with a good tune. The 6.0 is no more reliable than the others.
If you are going to "Baby it" then why try to make so much power? A mild heads and cam 6.0 with headers would be "fun" and still not be super expensive if you are not going to put your foot in it on a regular basis.
Any 4.8, 5.3, or 6.0 will be very reliable if set up well and with a good tune. The 6.0 is no more reliable than the others.
If you are going to "Baby it" then why try to make so much power? A mild heads and cam 6.0 with headers would be "fun" and still not be super expensive if you are not going to put your foot in it on a regular basis.
This isn't a Supra or a Diesel, we don't do sequential turbos lol. Twin's will be very complex in that small engine bay. I'd go large single that will still be "snappy" if sized correctly and be easier to deal with.
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There's really no engine work required. Would be good to open the rings some, for when you really want to start leaning on it.... and trust me...you will. Slap a set of good bearings in it and roll out. Tune work is what you want to focus on the most. And the cam you choose will play a lot into what torque you will make. 7875 here, and through the T56 it made 908rwtq.
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Based on what I've seen here and elsewhere, that power level wont require any additional hardparts or machining, unlike the older 96 and earlier small blocks. I spent 7K on forgings, going to four bolt splayed main caps, blueprinting my Turbo 96 LT1 , just to make it reliably hold up to what a bone stock 4.8/5.3 will happily shoulder with nothing more than opening the ring gaps a bit and, optionally, some good head studs.
There's videos out there where guys have taken 200K mile stock 4.8's, cleaned the stock parts, put it back together with a cam kit, turbo(s) and a tune and ripped off 900rwhp. The engines are so over-engineered in terms of strength. I sure love my current 5.3. Been to 29 psi so far and it doesn't complain one bit.
There's videos out there where guys have taken 200K mile stock 4.8's, cleaned the stock parts, put it back together with a cam kit, turbo(s) and a tune and ripped off 900rwhp. The engines are so over-engineered in terms of strength. I sure love my current 5.3. Been to 29 psi so far and it doesn't complain one bit.
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I did an compound turbo setup on a 4.8 a few years ago with a 60mm and an 80mm. Made 640hp on a mustang dyno at just 12 lbs and spool was great. Just because it's not common place and accepted on this forum, doesn't mean it won't work well...
You can have excellent spool and even more power with a 72 or 76mm and not have such a cumbersome or heavy setup. Having an 80mm and not making 900+hp seems like a waste.
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Joined: Mar 2014
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From: Ohio
He's probably not using a 7875 (at least not a cast wheel). They won't hold efficiency at that much boost.
I made 689hp / 674tq. with my T7875 on my SBE LS1 w/ cnc ported 317's and a turbo cam at 12-13 lbs. through a T56.
Outta do about the same with a 5.3 so my vote is for a 7875/7675 of some variant.
Outta do about the same with a 5.3 so my vote is for a 7875/7675 of some variant.
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Joined: Dec 2018
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From: MIAMI
yeah throw some e85 in that puppy and youre gonna be doing shotguns with the boys
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From: Norn Iron
And even that level 5 Magnum seems a bit OTT, when a stock T56 would handle the power at that weight quite easily.
So the best value unit would simply be a stock Magnum.. The level 5 wont actually be any stronger as it's still using all stock gears etc.
So the best value unit would simply be a stock Magnum.. The level 5 wont actually be any stronger as it's still using all stock gears etc.
I drive this car all over the place so pump fuel accessibility is paramount which is why I'm gonna do a race gas tune since there is a station fairly close to me that sells Trick 100 right outta the pump.
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From: MIAMI
AH NICE! yeah im doing a jy 5.3 with turbo cam , sheet metal intake , 102mm tb , 1218 springs , 7875 cast, 1000cc sep injectors , dual 450s and what not and of course e85 theres a station down the street from me so why not! i didnt even gap the rings lol