Boost pressure for built engine

[Jaden]

Then if I were you, I would look into Water/Meth injection.

Jaden

[Boofneenee]

I have never driven a boosted gt86 (apart from the phantom which doesn't count) but how is it that people feel that 300hp is simply not enough power? I mean geesh. My wives 2015 Rex has 270 hp and f'ing moves. Fast enough. Now 300 hp in a 2700 lb car is bordering stupid yet many posters (including above) speak ill of these lower outputs. Is higher hp simply for bragging rights at this point or do people honestly feel 300hp 86 is simply not powerful enough ?

[Jaden]

Originally Posted by Boofneenee

I have never driven a boosted gt86 (apart from the phantom which doesn't count) but how is it that people feel that 300hp is simply not enough power? I mean geesh. My wives 2015 Rex has 270 hp and f'ing moves. Fast enough. Now 300 hp in a 2700 lb car is bordering stupid yet many posters (including above) speak ill of these lower outputs. Is higher hp simply for bragging rights at this point or do people honestly feel 300hp 86 is simply not powerful enough ?

For a street driven car with little or no track time (for most people) 300whp in this car would be more than enough.

That's delving into stock corvette material...

Hell, this car is good with just 30 more hp, make it 130 more hp and it should be fine for the vast majority out there.

It's not going to be enough for some of us that just want a balls out fast fking car or a unique statement of seeing what we're capable of getting. That's what tunings all about after all.

Jaden

[ChrisD]

Forgot to update this thread, but I went ahead and ordered some carrillo 10:1 CR pistons and carrillo con rods, oh and stronger valve springs too. Took the engine out a couple of weeks ago and it is now being built. Should get it back the week after next (just waiting for new big end bearings to arrive at the mo).

So yeah I'll update this thread with my impressions of going 10:1 CR, once it has been mapped to increase the boost pressure.

Originally Posted by Boofneenee

I have never driven a boosted gt86 (apart from the phantom which doesn't count) but how is it that people feel that 300hp is simply not enough power? I mean geesh. My wives 2015 Rex has 270 hp and f'ing moves. Fast enough. Now 300 hp in a 2700 lb car is bordering stupid yet many posters (including above) speak ill of these lower outputs. Is higher hp simply for bragging rights at this point or do people honestly feel 300hp 86 is simply not powerful enough ?

lol 300 bhp is nowhere near stupid. I've got another car that's 725 bhp and that's perfectly usable. I've never had any problems caused by the extra power and I don't really understand why people think that kind of power is stupid.

Sure, you could be a moron and drive way too fast for the conditions and crash, but that's true of pretty much any car. Same goes for the reason of "you can't use all that power, the speed limit is only 70"... any modern car will do way over 70 mph, so by that logic you shouldn't have any car with over like 90 bhp.

Personally, the reason for wanting more power out of my GT86 is because I want to do more track days and drift days in it and its useful being able to just use the power to spin the wheels even in higher gears and at higher speeds. Plus faster acceleration is fun. That's the main reason people make cars faster at the end of the day, because they enjoy fast acceleration. Nothing wrong with that, unless you're doing it in a reckless way in the wrong places.

Plus you get used to it. Whatever power you've got, at first it seems really fast but eventually you get used to it and want a bit more.

[Matt@Cosworth]

Before bunging it all together I'd take a dremel and knock all the sharp edges off the piston crowns and combustion chamber as this'll buy you another 1-2 degrees of spark

also go for a 5W30 oil from the start

[ChrisD]

Originally Posted by Matt@Cosworth

Before bunging it all together I'd take a dremel and knock all the sharp edges off the piston crowns and combustion chamber as this'll buy you another 1-2 degrees of spark

also go for a 5W30 oil from the start

If that was the case then surely the company making the pistons would do that before sending them out?

As for oil yeah the engine builder recommended 5w30 too. Ive been running 0w30 for the last 6 months but will get some 5w30

[Matt@Cosworth]

Originally Posted by ChrisD

If that was the case then surely the company making the pistons would do that before sending them out?

As for oil yeah the engine builder recommended 5w30 too. Ive been running 0w30 for the last 6 months but will get some 5w30

you'd like to think so wouldn't you?
however deburring is a time consuming process that adds greatly to the cost of the part so they can't compete on price if they were to do this

still up to you, its your engine

[#maverick#]

Even 10:1 is to low of a compression if you plan on running e85 on this motor. Id rather have higher compression and a biggger turbo with less boost if this motor will be on e85 a lot.

But since youre on pump gas i would go 9:1 and a bigger turbo. How much power do you want?

[ChrisD]

Originally Posted by Matt@Cosworth

you'd like to think so wouldn't you?
however deburring is a time consuming process that adds greatly to the cost of the part so they can't compete on price if they were to do this

still up to you, its your engine

Ah ok, makes sense I guess. I wouldn't be comfortable doing that myself as I'd probably end up filing down something I shouldn't... but I'll mention it to the guy that's building the engine and see what he says. Cheers

[ChrisD]

Originally Posted by #maverick#

Even 10:1 is to low of a compression if you plan on running e85 on this motor. Id rather have higher compression and a biggger turbo with less boost if this motor will be on e85 a lot.

But since youre on pump gas i would go 9:1 and a bigger turbo. How much power do you want?

I don't plan on running E85 no. Too late for piston advice now anyway, I've already got the 10:1 pistons. Will report back on how I find it once we've got the engine back in and increased the boost.

[#maverick#]

Originally Posted by ChrisD

I don't plan on running E85 no. Too late for piston advice now anyway, I've already got the 10:1 pistons. Will report back on how I find it once we've got the engine back in and increased the boost.

Yea I was mobile and I didn't look at the dates. Honestly, I think you should get a bigger turbo. You will make more power with less boost at the expense of a little lag.

[Kiske]

ALS do it!

[killboy]

FWIW we have almost this exact same setup on our BRZ...AVO stage 3, billet wheel, race intercooler, forged internals, lower compression pistons, upgraded fuel injectors/pump, 93 octane. (no E85 around here)

Your original post asked about max boost and where it comes on, so to answer, ours is set to 14.9lbs and gets there at about 3300rpm, tapers a couple of psi near 6000 on. We make about 380whp on this one. We don't have upgraded springs though, (should have done that while in there but forgot) and I forget the CR of the pistons...try to get back with you on that. We have a built, supercharged FRS also and I get them confused.

Assuming you're ECUtek tuned, get your tuner to set you up with a traction control custom map if he hasn't already...basically it should pull timing based on difference in wheel speed front vs. rear when you have factory traction control turned off. It will still allow you to drift without blowing off the tires from boosting and slamming into redline killing your drift, but you can also have another map with TC disabled if you don't care for it. Really is amazing though both for nice controlled drifts and for launching hard out of turns.

[CSG Mike]

Originally Posted by killboy

Assuming you're ECUtek tuned, get your tuner to set you up with a traction control custom map if he hasn't already...basically it should pull timing based on difference in wheel speed front vs. rear when you have factory traction control turned off. It will still allow you to drift without blowing off the tires from boosting and slamming into redline killing your drift, but you can also have another map with TC disabled if you don't care for it. Really is amazing though both for nice controlled drifts and for launching hard out of turns.

Be careful with this; this comes at a very, VERY high thermal cost.