2387Turbo Egine (First Turbo)

[porkchop-rob]

Your 200hp goal will also greatly depend on how much boost you are running, gas octane and state of tune. Id imagine you will be able to hit your goal once you have it dialed in.

I will be mainly running E85. I will have a flex fuel sensor and a 93 octane tune just in case I am out and about with no E85 available. I am ok with running as much boost as necessary to make power goals. That is why I am attempting to "over-build" the longblock. My tuner is amazing and has decades of experience...with the Haltech, we can have selectable maps that are conservative for road trips and daily driving...and separate maps for track/strip/being stupid when the need arises.

Why not just buy a bigger crank and make it a stroker from the get go?

A few reasons....

1. I have the L5 Heads and want to use them. I feel that a larger engine will require more head.

2. Transmissions to handle much over 250HP are quite expensive.

3. I have a close friend with a 2275 that makes over 300HP at the tires and is daily driver dependable. That's too much for my car... way too much.

4. I have wanted to build a 1915 for a while.

5. Everybody has a stroker.

6. I like the idea of a peaky, ill mannered, demon possessed, two-strokish powerband. LOL

[petew]

I'm not sure if you've driven a turbo car, but let me make a few points in response to what you've said above...

Firstly, ANY ecu will allow you to run different maps. Haltech stuff is ok, but the reason many of us MS stuff is it's all those features only a LOT cheaper. If your tuner can use Haltech, he could easily use MS. Anyhow, it's your car so whatever you choose.

A few other things...
1. Re your heads, I'm not an expert, but turbos fix a lot of the head flow issues NA motors have by pressurizing them.

2. Power doesn't kill transmissions. Torque and specifically "shock loading" kills them. So there are a bunch of guys down here who ran dead stock single side plate trans behind 300hp subaru turbo engines and didn't kill them. It's all about mechanical sympathy. However, I take your point, if you want to side step the clutch at the strip with slicks. Even then, a sensible left foot will cost less and get you further.

6. Turbos, unlike high revving NA motors are all about torque. The earlier it comes on, the better. A 1000rpm band of crazy boost seems cool, but in practice it's much more dangerous than a 4000rpm band of generous torque. It's also not fast and creates situations where you can break trans.

Whether you build a stroker or not is up to you, but in the end I'd be aiming for a motor that is like your friends stroker. Super reliable, with a huge fat torque band.

[Clonebug]

If you want it to be a daily build it to rev to 6000 rpm but if you want max hp the easiest way to get it is rev the plink out of it.
All the HP calculators I use show that rpm is king for hp. Add boost and you will have plenty.

The tradeoff is your low end will suffer because your cam and turbo will be set for the high rpm power.

For a street engine you can't beat getting full boost by 3500 to 3800 rpm and keeping the revs to 5400-5700 rpm. If boost comes in later you will get lag between shifts unless you rev it high enough to get past it. My trans drops about 1500 rpm per shift so do the math on the lag issue.

[porkchop-rob]

My friend has a wedgemated 86 crank and flywheel that he will sell me....but....

Wont that require me to buy new/larger valves heads?

[Clonebug]

That's a whole new can of worms....

[petew]

My friend has a wedgemated 86 crank and flywheel that he will sell me....but....

Wont that require me to buy new/larger valves heads?

http://www.drdracingheads.com/xcart/DRD ... heads.html

Just looked up his page. It said it supports 170hp at 6500rpm (NA I assume). I'm no expert, but that's close to your HP target right? So a little boost should get you there and give you a 1000rpm more if you really want it.

[porkchop-rob]

My friend has a wedgemated 86 crank and flywheel that he will sell me....but....

Wont that require me to buy new/larger valves heads?

http://www.drdracingheads.com/xcart/DRD ... heads.html

Just looked up his page. It said it supports 170hp at 6500rpm (NA I assume). I'm no expert, but that's close to your HP target right? So a little boost should get you there and give you a 1000rpm more if you really want it.

Yeah, target is 200 at the wheels. I guess worst case scaenario...I can purchase and swap heads later on if needed.

[petew]

Yeah, target is 200 at the wheels. I guess worst case scaenario...I can purchase and swap heads later on if needed.

Don't you love it when a plan comes off?

[porkchop-rob]

I built a spreadsheet for this engine and input EVERYTHING I could think of that would be needed to complete the project.

Total bill for engine, turbo, EFI, and tuning was right about 10K. That's the only reason I started giving any real thought to ditching the 69 crank. There's no way I could convince the wife do this more than once. LOL

[Clonebug]

I built my 1679 fir $1300.00
EFI was another $1300.00 for the first MS-1.

I......nor my wife for that matter... could not fathom putting that much into an engine.
I have that into my whole buggy over the 16 years I have spent building, driving and upgrading it...
In my opinion you don't want to be learning how to tune a turbo EFI engine when you have that much tied up in it.
There won't be enough tears in the world to cover the sadness if you screw up and blow it to kingdom come.

This is only my opinion.... you are the engineer and the mechanic.

[porkchop-rob]

I built my 1679 fir $1300.00
EFI was another $1300.00 for the first MS-1.

I wish I could do something like this. Somehow, every time I get into a project, it goes from "lets freshen this engine up" to "Lets build a zero mile stroker!" or some equivalent. Project creep is real problem at my house.

[Clonebug]

Try to keep that from happening. A 1915 with 15 lbs boost should give you an easy 180 hp.
Getting it there will take a while. It's not like you can just crank the boost and expect it to run great without a few hiccups and challenges.
The only thing good about a big stroker is you get to keep the boost lower for your targeted hp.... at what cost though.

Take that 1915.....balance it good with the C/W crank and everything else and turn it to 7000 rpm.....you will be able to get 250 hp.

In fact....using a calculator I like you can make 278 hp at 7000 rpm at 15 lbs boost if you keep your IAT's down to 130 degrees.
You will need about 390 cfm which is the max my turbo will put out efficiently.
If you wanted a conservative 200-250 you could easily do it with a WRX turbo and your engine with some attention to detail and 6500 rpm.

[Chip Birks]

The only thing good about a big stroker is you get to keep the boost lower for your targeted hp.... at what cost though?

There are definietly benefits to keeping boost low though. Stroke allows you to make all the power much earlier and with much less effort. Thats going to allow things to last much longer. Nothing wrong with that. Its an investment into the future.