What would it take to safely run a 930 at 1 bar on the track?

[bpu699]

Ok, I am all over the place. Plan to rebuild a reportedly recently rebuilt motor due to a busted dilivar head stud and pitting on one cam. Part of me says to do just what needs to be done, and get back to driving.

Part, says to make to motor as bullet proof as possible and turn up the boost.

Prior owner was running 1.2 bar. I run 0.8 as I didn't want to grenade the motor...

Car has updated fuel head, oversized inter cooler, modified k27 turbo... Boost dial.

Prior owner said he got 400 hp out of it. I have been babying it, cause that's my nature. Kind of a low risk guy in a sense...

Turning down the boost, has caused rich afrs under boost, was going to adjust the WUR next...


But now, since I will have most of the motor apart anyway...maybe I can finish what the po started.

If I add super tech head studs, arp rod bolts...

Can I safely enjoy 1 bar on the track??? Not looking for crazy horsepower, but 1 bar would probably get me 375 hp... Which could be a bunch of fun on the track.

Would I need to do anything else? Just flow check the injectors?

Already added a front cooler and it runs quite cool...

Can such a motor last 50,000 miles???

Armchair quarterbacks, chime in .

[Alan L]

Check my specs below. I regularly run 1 bar at track. Not always, but often - as required (EBC).
I have had no mechanical breaks. No broken rings/studs etc. I run AFRs as high as 12.5. Sometimes more - but I would prefer no more than 12.5. I am still struggling to get enough fuel at 6000rpm.
I ran 1 bar with the stock IC - but sprayed water over it - same reasons as you state. I don't want to destroy the motor. Most of what I do to it is to try and preserve it. I have upgraded to 964 IC. For performance and longevity. But these engines are tough and 1 bar is no issue as long as you are sensible. I used to worry about EGT - the dial was always pegged. So I disconnected it. ARP rod bolts would be useful, but not essential (I am still running stock). I think they are more important for high revs rather than boost, and I limit my revs.
Regards
Alan

[VZ935]

I ran 1 bar all day hard on the track with my street 930. It was super fun with DOT tires
3.4
SC ish cams
twin plug
boat tailed the webs
crank fire
big intercooler
front mounted oil cooler
Kendall 50w

[RarlyL8]

You have a larger intercooler so 1.0bar is safe.

Alan the -007 will support 500hp but you need dual 044 pumps and set the system pressure at 100psi. For 400hp there shouldn't be any issues, may need to turn it up 10%.

[bpu699]

Thanks guys...

My afr is 10 at 6000 rpm and 0.8 to 0.9 boost.

Chased boost leaks for a long time, never found any. Really think the prior guy just set it all to run 1.2... Was going to rest the boost pressure on the WUR...

I'm not brave enough to run 1.2 bar...

I assume you guys are running arp or similar head studs???

Or, stock steel?

At what point do you "need" arp?

The arp rod bolts would be more of a safety measure in case of over rev...

[RarlyL8]

The stronger head studs help with high boost but also high rpm. There are better ways to make power than just increasing boost. If you keep the standard redline and top off at 1.0bar stock studs should be fine. If you have to rebuild the engine anyway then add the ARPs for peace of mind. We put them in every build where the studs are replaced.

[Alan L]

I have ARP studs. But never broke any prior to replacing, that I can recall. Just replaced with ARP because I was in there.
Brian - I maxed out the flows on the 007 head, until one would go no more. There may still be a bit left in the other 5 but I dialled them all in to balance with the lowest flow. No more adjustment. I had increased the flow about 10% over what it was set at when I got it back from the mods.
Regards
Alan

[Jim2]

What fuel would you plan to run if you did carry through with sustained 1 bar?

[bpu699]

Originally Posted by Jim2

What fuel would you plan to run if you did carry through with sustained 1 bar?

Well, I was hoping simply premium.

Race gas around here is $10+ a gallon. More at the track...

Do I need race gas?

Would love a knock sensor

[Menmojo]

I have been running 1 bar at the track for years without any issues. Stock motor with a K27 , larger intercooler, cold air intake and headers with a zork tube. I always run 110 octane race gas as added insurance against detonation.

[Alan L]

I'm running our highest grade pump gas (98) which I think is equiv to your 93. My other option is Av gas - but the lead kills the AFR probe. Quick.
Alan

[dos531]

Efi with knock sensing would definitely extend the life of the motor. 1bar is peanuts

Sent from my SM-G950U using Tapatalk

[RarlyL8]

There should be no problems and no special fuel needed to run 1.0bar at the track. Only caveats are running too much timing or high AFRs. Big intercooler should keep temps down.

Alan something isn't right if you've maxed out the -007 at 370whp. Shoot me an email and maybe we can figure it out, don't want to highjack this thread.

[bpu699]

My timing is about 26 degrees at 5000 rpm, with a 15 degree retard under boost. Which I figure is really conservative... I have the msd boost retard, set really conservative...

Taking my motor apart I see I do have the black euro fuel distributor, which is supposedly the better one...

Under peak boost my afrs are 10 or less...working on fixing that...

Previous owner clearly did work on the motor.... He ran a lot of boost... It's probably easier to run more boost than undo all the work he did...

I kind of wonder if I have arp rod bolts already...

[Tippy]

Yeah, at 15 degrees, you are super conservative.

As long as you have a big IC and keep the AFR's in check, enjoy the added power.

For reference, I see only 10 to at most 15 degrees of inlet temps over ambient at temps.

Meaning, our IC designs allow a very safe margin.

[Alan L]

If you have ARP bolts already you will see a 12 point head (star like) on the nuts, and ARP is stamped in small letters on the bolt head. You won't see the bolt head - but maybe with a small mirror and torch if you can get down the case hole .
Brian, I will shoot you a PM.
Regards
Alan

[T77911S]

make sure the engine and IC are sealed very well.
any air leaks is air that is not being pulled thru the IC. engine air leaks are worse as hot air is pulled in.

these are tough engines, the problem is over boost results in broken rings and there are a lot of engine running with broken rings and don't know it.

[bpu699]

Originally Posted by T77911S

make sure the engine and IC are sealed very well.
any air leaks is air that is not being pulled thru the IC. engine air leaks are worse as hot air is pulled in.

these are tough engines, the problem is over boost results in broken rings and there are a lot of engine running with broken rings and don't know it.

How would you know you have broken rings? If the leakdown is normal, can you assume the rings are fine?

[Tippy]

Originally Posted by bpu699

How would you know you have broken rings? If the leakdown is normal, can you assume the rings are fine?

From reading here, no, unfortunately.

Some have had ok numbers but the rings were broken.

[16Volt]

Before my motor grenaded -
12psi of boost
Stock head bolts
Reground SC profile-ish cams
3LDZ
B&B Headers/Exhaust/Intercooler

I dynoed the car before badness happened it and it put 337hp to the wheels, with 100F+ intake temps before the intercooler.

Initially I thought I had just puked a turbo but before I put in a K27/K29 did a leak down, bad news. When I opened the motor I had a bunch of broken rings, this was likely my fault though.

New build adds:
Twin plug heads
SC-ish
crank fired ignition
knock sensing
RPM switch/adjustable WUR
EBC
K27/K29

I hope to run a bar safely but I am super paranoid I wont be able to fuel it. But I feel allot safer with a .5 WG spring, EBC and knock sensing regardless.