BorgWarner EFR Discussion

[jsol]

just if you are running a quick spool, you are going to want a A/R of 1.00 or more.

Why is that?

[jsol]

If you need a tube mani i can get you one for a fairly price.

I'm interested, can you pm me a link? Ideally something like FRP or Iroz but without the lead time

[gabriel.b]

If you run a low A/R with a quick spool valve, when the quick spool valve is shut you will spool very quickly and the valve will open very quickly causing inconsistent boost. and you might over spin the turbo if your solenoid can not open the QSV fast enough.
At A/R of 1.00 with it shut, you have an A/R of about 0.5 (its actually a little lower but you can assume half)
.5 A/r gives great spool, and the 1.00 with it open will give you good top end power. and it wont be slamming open and close every time you get on/off the throttle.

You can run with less than 1.00, but it makes little sense to do so.

[SE_30]

Here's my 8374EFR/ 1.05ar on an Iroz manifold. No quick spool valve. All achieved on Shell V Power.

[SE_30]

stuart (se-30) uses a efr twinscroll turbo,check this thread
http://www.s2forum.com/forum/showthr...t=77130&page=6

Thanks Nick..

[jsol]

Here's my 8374EFR/ 1.05ar on an Iroz manifold. No quick spool valve. All achieved on Shell V Power.

That's very impressive. I wonder if a 1.45 AR with QSV would have similar spool with a bit more top end. Your max HP is still well below the 8krpm limit of the stock(ish) head/oil pump.

[PRY4SNO]

The thing about stock 07k heads is, from what I've read, they start where a stage 4 CNC port job leaves off on the urI5 motors. There is some overlap in capacity, although not a direct comparison especially with the VVT. I offered it as a point of comparison to see how they respond to a 2.5L inline 5.

[gabriel.b]

Yes it has been said that in order to make a 20v head flow like an O7k does stock, you need about $6000 in parts and labor.
Roller rocker lifters make a huge difference in the dynamic flow over cam on bucket type heads.

[jsol]

The thing about stock 07k heads is, from what I've read, they start where a stage 4 CNC port job leaves off on the urI5 motors. There is some overlap in capacity, although not a direct comparison especially with the VVT. I offered it as a point of comparison to see how they respond to a 2.5L inline 5.

Sorry, I didn't want to come across so blunt. The vomit comet has alot of info to utilise.

[PRY4SNO]

Yes it has been said that in order to make a 20v head flow like an O7k does stock, you need about $6000 in parts and labor.
Roller rocker lifters make a huge difference in the dynamic flow over cam on bucket type heads.

Yes. The new motors gain a lot where our old ones left off. But they do give a glimpse toward the potential of our motors.

Sorry, I didn't want to come across so blunt. The vomit comet has alot of info to utilise.

Not at all, it's a good cross comparison for some and not at all for others. I was just throwing it out there as an operating build with frequent updates for people to learn from.

[diesel des]

Yes. The new motors gain a lot where our old ones left off. But they do give a glimpse toward the potential of our motors.






Not at all, it's a good cross comparison for some and not at all for others. I was just throwing it out there as an operating build with frequent updates for people to learn from.

O7k head might flow better than a stock aan head but the cams seem poor?

Sent from my LG-H955 using Tapatalk

[PRY4SNO]

O7k head might flow better than a stock aan head but the cams seem poor?

Sent from my LG-H955 using Tapatalk

True, but the 07k head's basement is at the ceiling of the urI5.

Cams are about as simple of a replacement part you'll find. Any shade tree mechanic can DIY within a couple beers.

CNC head work and valve springs, retainers, etc are a bit more advanced.

Sent from my SM-G900W8 using Tapatalk

[diesel des]

True, but the 07k head's basement is at the ceiling of the urI5.

Cams are about as simple of a replacement part you'll find. Any shade tree mechanic can DIY within a couple beers.

CNC head work and valve springs, retainers, etc ae a bit more advanced.

Sent from my SM-G900W8 using Tapatalk

Yep understood. Has anyone flow benched a 07k to see how it actually compares to a "real" i520vt?

Sent from my LG-H955 using Tapatalk

[jsol]

Anyone know where you can get these housings?;

http://www.evoxforums.com/forums/showthread.php?t=273897

[PRY4SNO]

I got my EFR (first for a 20vt) from Mike Hood of Ringer Racing. He was awesome to deal with, had great pricing, super fast delivery and feedback to questions.

http://www.ringer-racing.com/category.sc?categoryId=185

Sent from my SM-G900W8 using Tapatalk