[335iJWC]

Originally Posted by onesuperboi

Remember, the difference between RBs vs a single turbo is that there would be more hp in the higher rpms (greater than 5500 rpm). So, you won't have that usual dropout that we usually see with our turbos and upgraded twins.

500 HP and 500 TQ doesn't mean anything unless you see where those numbers are made.

agreed but on a single set up it will be more like 500 HP and 400 TQ

[jippii ensio]

Originally Posted by onesuperboi

Remember, the difference between RBs vs a single turbo is that there would be more hp in the higher rpms (greater than 5500 rpm). So, you won't have that usual dropout that we usually see with our turbos and upgraded twins.

500 HP and 500 TQ doesn't mean anything unless you see where those numbers are made.

Have a look at the RB dynos. They hold 500whp over a wide range of rpm. They drop below just a bit before redline at 6500rpm. If HPF would have 500whp only, it would be lacking in area under curve.

A turbo is too big if the engine is not able to tap its full potential before the redline. So the power should start to decrease just a tad before redline for perfect turbo sizing.

Edit: of course turbo sizing depends also on the application. DD being different from drag racing.

[scottp999]

Lots of questions will be answered soon. I'm interested to see what Cobb can do with RB's as they could go a few PSI higher with the right fueling, if they can get it out of the stock DI system. RB's are under $5k with install if you do all of the replacement parts including new oil lines.

On the HPF kit, it will be interesting to see where they hit a bottleneck on stage 2. There have been some concerns about how much the stock head can flow. If HPF has the fuel and the turbo, we should find out at what level the head needs to be addressed.

In the end, like someone said, it's what you want to do with your car. The potential to ladder up the stages with HPF is appealing for those that want to make a significant investment in this platform.

So much fun is in store for this year! Get your wallets ready. Oh, and I bet the Drive Shaft Shop gets a few more upgraded axle orders this year.

[rader1]

The trickle down of the coming developments are what i'm interested in. I can remember when hi boost in the midrange was unheard of until Cobb pioneered it. Now it's the norm, i'm hoping similar dicoveries can be made on the big dogs can help out the guys just running the stock twins.

[E92TTKING]

I smell lots of exploding axles

[Q4P]

Originally Posted by rader1

The HPF kit is roughly twice the price of RBs. As far as performance goes we won't know until they dyno it. I'm thinking the performace difference won't be enought to justify the price on stage 1. stage 2 will probably be the kit to have. If stage 1 makes ~500whp then i don't see the value to the kit. As far as stage 2 goes, if it's only ~$3K more for +800whp($9K-$10K) then that would definately be worth it to some people.
Who knows stage 1 might make ~650whp. That would be some pretty good stuff, until we see HP/TQ numbers it's all speculation.

fully agreed +1

although 500 WHP on low boost, pump gas would be nice; I doubt it would be worth it at this price

[rader1]

Originally Posted by Questforpower

fully agreed +1

although 500 WHP on low boost, pump gas would be nice; I doubt it would be worth it at this price

I wonder what the definition for "low boost" will be with single turbo setups lol? In the supra community the phrase "life begins at 30psi" is very common

[Q4P]

Originally Posted by rader1

I wonder what the definition for "low boost" will be with single turbo setups lol? In the supra community the phrase "life begins at 30psi" is very common

you can probably divide that by 2 and subtract 2.

The stock turbos blow the engine at above 20 psi.

[rader1]

Originally Posted by Questforpower

you can probably divide that by 2 and subtract 2.

The stock turbos blow the engine at above 20 psi.

i dont think we'll see 500whp w/o meth below 18psi, depending on how much timing we can throw at it. Then the 500whp will only be available after 5.5Krpm. There are definitely going to be trade offs to a single turbo swap.


Ive seen stock engine single turbo supras make real good power, but i'd never admit that to a supra owner lol

[jpirelli]

$5950? gtfo

[Q4P]

Originally Posted by rader1

i dont think we'll see 500whp w/o meth below 18psi, depending on how much timing we can throw at it. Then the 500whp will only be available after 5.5Krpm. There are definitely going to be trade offs to a single turbo swap.


Ive seen stock engine single turbo supras make real good power, but i'd never admit that to a supra owner lol

I am not an expert but wouldn't 18 PSI on stock internals w a big turbo w/o meth be a definitive engine explosion? You can't even do that with the stock turbo which blows considerably less air.

[Jeff@TopGearSolutions]

You guys are confusing 18 PSI on small turbos and 18 PSI on a big turbo. 2 different amounts of air (CFM) and power.

[Q4P]

Originally Posted by Jeff@topgearsolutions

You guys are confusing 18 PSI on small turbos and 18 PSI on a big turbo. 2 different amounts of air (CFM) and power.

That's my point exactly, you definitely can't run the same amount of boost on a big turbo as on the stock twins without causing much trouble. This is especially the case if we are talking without meth. If 18 PSI isn't doable on the stock turbos without meth... it sure as anything won't be possible on the big turbo, when you have an even higher CFM...

With that said, to produce 500 WHP without meth on this platform on pump gas would require the bigger turbo running at a much lower boost than the stocker, my guess would be below 15 PSI... which I am not even sure is possible.

[ExpensiveTaste]

Originally Posted by Jeff@topgearsolutions

You guys are confusing 18 PSI on small turbos and 18 PSI on a big turbo. 2 different amounts of air (CFM) and power.

Please explain because I don't understand. 18psi on the intake side of the cylinder head is 18psi no matter what the size of the turbo/turbos...You may transfer less heat from a more efficient turbocharger which would make the air more dense, but the CFM would not change. Please correct me if I'm wrong.

[bryce]

Originally Posted by ExpensiveTaste

Please explain because I don't understand. 18psi on the intake side of the cylinder head is 18psi no matter what the size of the turbo/turbos...You may transfer less heat from a more efficient turbocharger which would make the air more dense, but the CFM would not change. Please correct me if I'm wrong.

18psi on a large turbo means there is much greater air mass than the stock twins at the same boost levels.

[ExpensiveTaste]

Originally Posted by bryce

18psi on a large turbo means there is much greater air mass than the stock twins at the same boost levels.

Ok, ya, that's what I thought. Keeping the air cooler means a more dense intake charge.

[bryce]

Originally Posted by ExpensiveTaste

Ok, ya, that's what I thought. Keeping the air cooler means a more dense intake charge.

Temperature isn't the primary factor; its simply much more air mass pushed into the intake manifold by the larger turbo. 18 psi from a 76mm turbo should be good for 700whp plus, depending on the engine. 18 psi from stock turbo's is nowhere near that power potential on the same engine

[Eleventeen]

Originally Posted by Questforpower

I am not an expert but wouldn't 18 PSI on stock internals w a big turbo w/o meth be a definitive engine explosion? You can't even do that with the stock turbo which blows considerably less air.

There's probably about a 50-100*F difference in IAT's between 18psi on stockers, and 18psi on a big efficient turbo. Much less chance for detonation with a more efficient turbo.

[rader1]

Originally Posted by Questforpower

I am not an expert but wouldn't 18 PSI on stock internals w a big turbo w/o meth be a definitive engine explosion? You can't even do that with the stock turbo which blows considerably less air.

Dzenno made 471rwhp on RB turbos running 20psi tapering to 18psi on straight 93, no meth. And that car is still strong as ever.
I would imagine a more effecient turbo would make 18psi easier on the engine, not the opposite. However, i dont know how much a single pt62 can outflow a pair of RBs. It might not be a HUGE difference in the CFM output. Remember they are small turbos, but there are 2 of them.

[ExpensiveTaste]

Originally Posted by bryce

Temperature isn't the primary factor; its simply much more air mass pushed into the intake manifold by the larger turbo. 18 psi from a 76mm turbo should be good for 700whp plus, depending on the engine. 18 psi from stock turbo's is nowhere near that power potential on the same engine

PV=nRT

Pressure * Volume = a constant * a constant * Temperature

So if the Pressure remains the same and the volume remains the same (stock cylinder head intake ports don't change in size), then it only leaves temperature. Just saying...

[Q4P]

Originally Posted by Eleventeen

There's probably about a 50-100*F difference in IAT's between 18psi on stockers, and 18psi on a big efficient turbo. Much less chance for detonation with a more efficient turbo.

Originally Posted by rader1

Dzenno made 471rwhp on RB turbos running 20psi tapering to 18psi on straight 93, no meth. And that car is still strong as ever.
I would imagine a more effecient turbo would make 18psi easier on the engine, not the opposite. However, i dont know how much a single pt62 can outflow a pair of RBs. It might not be a HUGE difference in the CFM output. Remember they are small turbos, but there are 2 of them.

I look forward to seeing what HPF can do... Dzenno's results are pretty much exactly what I want... that's a car good for a 120 trap without trying and compromises no daily drive ability.

[turb0mik3]

Good stuff HPF. 550whp + 91 + meth is ideal for the tracking enthusiast such as myself. Make it happen! haha.