I CANT MAKE A DECISION!!! Jrsc or edelbrock.

[B T]

Originally Posted by toast

Edelbrock really needs either an electronic bypass valve or a vacuum one with an adjustable spring so that you can tailor it to your needs.

I thought you were working on one?

[86TOYO2k17]

Originally Posted by CSG Mike

Exact opposite. The quicker/earlier the turbo spools, the more load it puts on your rods and bearings, and the more you're stressing your engine.

No matter how well done the turbo setup is, turbo lag is a thing. It's just physics.

But a turbo making 300whp and a SC making 300whp, wouldn't the turbo be stressing the engine less in regards to power output? As in 300whp on a turbo is say 350hp crank but 300whp on a SC is more like 370hp crank as the SC has much more parasitic loss to create the boost/power. Also the fact a turbo can make 300whp with less boost compared to a SC making 300whp. So your engine is effectively stressed less making less crank hp for the same whp, as well as your effective compression ratio is lower at the same whp level as you need less boost to make the same power.

also looking at torque curve of attached SC (DT) vs turbo (Drift Office) both making 300whp peak, however the SC is making a lot more torque sooner down low. Based on all the aforementioned I don't see how the turbo would be stressing the engine more.

also i never stated lag would be non-existent, i even stated on the pros and cons as a con for the turbo, however a good setup (especially if you don't want to make massive amounts of power) can drastically minimize lag to not be that big of a deal.

Originally Posted by CSG Mike

My GReddy builds boost quickly enough that quick blips for heel-toe downshifts build boost. I can have full boost before 3000 rpms regardless of conditions. Unfortunately an inertial dyno will not be able to show this, as loaded driving conditions and dynos are not quite the same.

Edit: also adding JRSC / KWSC for torque curve/power delivery comparison. Looks a lot closer to a turbo then a positive displacement charger.

[bfrank1972]

Originally Posted by 86TOYO2k17

But a turbo making 300whp and a SC making 300whp, wouldn't the turbo be stressing the engine less in regards to power output? As in 300whp on a turbo is say 350hp crank but 300whp on a SC is more like 370hp crank as the SC has much more parasitic loss to create the boost/power. Also the fact a turbo can make 300whp with less boost compared to a SC making 300whp. So your engine is effectively stressed less making less crank hp for the same whp, as well as your effective compression ratio is lower at the same whp level as you need less boost to make the same power.

also looking at torque curve of attached SC (DT) vs turbo (Drift Office) both making 300whp peak, however the SC is making a lot more torque sooner down low. Based on all the aforementioned I don't see how the turbo would be stressing the engine more.

also i never stated lag would be non-existent, i even stated on the pros and cons as a con for the turbo, however a good setup (especially if you don't want to make massive amounts of power) can drastically minimize lag to not be that big of a deal.



Edit: also adding JRSC / KWSC for torque curve/power delivery comparison. Looks a lot closer to a turbo then a positive displacement charger.

That's certainly true. I think what they probably were referring to is the low RPM torque output. A properly sized/well thought out street turbo kit will build boost quickly at low RPM and put a lot of stress on the rods if you floor it at 3000 rpm. A centrifugal unit won't do that. The positive displacement units would likely induce more low RPM rod stress as well.

[toast]

Originally Posted by B T

I thought you were working on one?

I am, but I'm a hack. If a company that employed actual electrical and mechanical engineers would do it I would hope they could to it in a more robust way than what I'm doing.

I have it working on the bench. Have to come up with a way to mount the cable actuation on the SC itself without having to take it off and flip it over.

[toast]

Originally Posted by bfrank1972

That's certainly true. I think what they probably were referring to is the low RPM torque output. A properly sized/well thought out street turbo kit will build boost quickly at low RPM and put a lot of stress on the rods if you floor it at 3000 rpm. A centrifugal unit won't do that. The positive displacement units would likely induce more low RPM rod stress as well.

An Edelbrock doesn't make much boost down low, it still climbs linearly with rpm. Certainly more than a centrifugal unit, but nowhere near what happens if you're rolling along in 4th gear on a back road at 2500 rpm and lean into the throttle - you're going to hit full boost by 3000 rpm.

[Irace86.2.0]

^^^ Exactly. The turbo might have lag, yet it is load dependent, so it'll build boost, but the supercharger will just pud along until rpms increase enough to get boost, so it will feel like it has supercharger lag; this isn't accurate because there is no lag, but there is rpm-dependency-delay. In this regard, turbos can lead to lazy shifting, and superchargers require downshifting to get into bigger boost numbers, but when that happens the boost is instant, where downshifting in a turbocharged car will still have some lag, even with a small turbo.

[CSG Mike]

Originally Posted by Irace86.2.0

^^^ Exactly. The turbo might have lag, yet it is load dependent, so it'll build boost, but the supercharger will just pud along until rpms increase enough to get boost, so it will feel like it has supercharger lag; this isn't accurate because there is no lag, but there is rpm-dependency-delay. In this regard, turbos can lead to lazy shifting, and superchargers require downshifting to get into bigger boost numbers, but when that happens the boost is instant, where downshifting in a turbocharged car will still have some lag, even with a small turbo.

Unless you keep your charge pipes pressurized between shifts like I do... or run some sort of anti-lag.

[Irace86.2.0]

Originally Posted by CSG Mike

Unless you keep your charge pipes pressurized between shifts like I do... or run some sort of anti-lag.

Something like this technique... go to 10:30...

[ame]https://www.youtube.com/watch?v=p10m0Jdk8tc[/ame]

[casing]

i still cant decide. I dont want turbo. its down two these two,
edlebrock and jackson.


I CANNOT DECIDE

[Joveen]

Jackson racing!!!

Sent from my SM-N960U using Tapatalk

[toast]

Honestly if I had it to do over I would get the Jackson simply because you wouldn't need a new clutch since the power is up top. Even an Exedy stage 1 introduces a lot of annoying harmonics when driving; seems unique to this car, maybe because the drivetrain is so light. My STI got upgraded to an ACT extreme clutch and there wasn't an iota of extra noise in the driveline. This car gets a tiny upgrade in holding power and it sounds like I have straight cut gears when decelerating from 3-2k.

[why?]

1. Flip a coin.

2. See which one your local tuner is better at tuning so you won't blow up your engine.

[StraightOuttaCanadaEh]

Originally Posted by toast

it sounds like I have straight cut gears when decelerating from 3-2k.

That's amazing lol... I want that!

[StraightOuttaCanadaEh]

I've done tons of research and been back and forth between turbo and edelbrock and different types of sc a million times and I always come back to edelbrock because it makes the most sense for me. JRSC sounds like it's more for track applications with not much power down low. Watching the youtube reactions of jrsc vs edelbrock, they are always like hysterically laughing and amazed with an edelbrock and "meh this is nothing crazy" with a JRSC. I'd go with the edelbrock