Safe amount of boost on stock engine?
 

Anyone know what might be a safe amount to boost on a stock engine before having to build the internals?

Just weighing the option and prices for now.

I dont think anyone knows. if you boost at the levels the tunes come in i would say thats safe.

All depends on your tune , kit and the way you intend to drive it

My estimates from hours of lurking around here

10~ on 91
14~ on 93 thanks to king tut
16sh on 9X + WMI
20+ on e85

Obviously this is the amount of boost, you have to consider fuel issues , drivetrain and cooling

My 1 cent :mad0259:

Thanks. At least this can get me in the ball park on what to aim for. I think I'm going to aim at 8psi for now to be safe. Later on probably higher if I want to change the internals I can always crank it up.

I think on 91 ( your location says CA) you'd be fine with 7sh 8sh

I'm going boosted On 91 and e85 soon hopefully, i'll stay low for a month or two until I throw some low cr rods and pistons.

I heard via the ecutek and haltech networks of a few cars throwing rods around 300 whp! :eyebulge:

Apparently it's just a load limit on the rod when it sees bursts of extreme accel.

There's a lot of big number charts on here but how many of them saw extended, high load use outside of a dyno room?

If I'm not mistaken a fair number of them have seen a decent amount track and Drag use at 250+ whp

Water/Meth injection seems like a good option if you have limited access to E85 or want to wait on building the motor. Ptuning is pulling 400whp on 93 and meth injection on the stock block. More than enough to get you in all sorts of trouble

While many people on the forum or the internet may throw this out and around. Personally, I do not enjoy the idea of E85 neither do Meth injections. If I was to do this with my VR4, she would break 550 AWHP.

Meth Injections = Rusty part + 70% more for catastrophic failure (Not practical for every armatures )

E85 = Very few fuel stations, and the Fuel consumption is 2-3x times more of the traditional 93. Your full tank of gas may just serve you 1/3 of the original mileage range

The best possible is to build a car running on 93, with conservative tune.

The good news is that with 93, and running around 10 PSI will have you in the range of 300-350 RWHP already. This already makes this car into a beast

True, speaking for my self Im aiming for the 300 mark on e85 before I build my motor with a simple rod piston setup.
Aren't you pushing 3xx whp on a stock block @nix ?

Yeah with about 40% DI to port, over rich map and extra squirts of fuel at points for cooling. I wouldn't expect them to last at this power. I don't really want to go with a flat top head and lose the swirl atomisation of DI so waiting on options.

im on 93 and 5.3 psi at 286hp and with exhaust close to 300 if not 300 so its very safe because i beat it up. next week or two ill be on 10 psi pump and e85 so hopefully ill be around the 400++ so ill beat that up and tell you if its safe also but it should be lol

It is really more of a three variable equation with two primary variables. The two primary variables are boost and timing and the third is your air/fuel ratio. For a given boost/timing/afr there is a maximum brake torque your car can achieve. For most turbo cars this is a few degrees of timing before knock occurs although it can also be past the knock threshold and be unachieveable at a given boost level. So in reality you can either run more boost and pull more timing or run less boost and run more timing. The fact is that knock becomes the limiting factor. Running a richer afr can help move this knock threshold a little bit as well which is why it is a lesser variable in the equation.

It seems most people on this site are not really that interested in the timing that cars are running as compared to the boost that they are running. The cars making good horsepower numbers on lower boost levels are going to be running considerably more timing. You throw in some E85 or meth and again you are going to be running considerably more timing. To get the total picture of how a kit is running you would need to see dyno plots with horespower, torque, afr, boost, and ignition timing.

TL;DR: There is no correct answer to your question.

who ever has the better tuner lol pretty much ^^