A different type of question... A lot of people ask how much their combo should make, power wise. Me, I want to know what the reasonable limits are on what I've built. Here is my engine combo:

GM LH6 5.3 aluminum block, .030 over. Block was fully CNC machined at Steve Morris engines, bored, torque plate honed, decked, and align honed
Factory crank from the LH6, uncut
Summit Pro LS H-beam rods with ARP 2000 capscrews
Summit Pro LS 2CC dome pistons, 3.810 bore
New factory main studs
ARP head studs
BTR small bore LS9 gaskets
AFR Enforcer heads, .425" thick deck surface
10.5:1 Compression

I built this myself, and I know it's built correctly. Cam is a BTR Stage 2 turbo cam, but that could change if I ever decide to max this thing out. Turbo is a VS racing Gen 2.5 Billet 78/75 w/ 1.25 A/R. That too will change if I want to push the envelope.

Given my bottom end specs, I'd venture to guess that it could easily handle 1000 RWHP. I'm not too experienced in the turbo world, though, so I'm looking for input as to whether or not I'd want to go that far with the components I've got. Other people here have built far more powerful engines than I have, and I'm sure a fair amount have blown some up, lol. I just don't want to get greedy and end up driving over my crank.

 

As far as the long block I'd feel comfortable with that over 1000 and maybe up to 1200 rwhp but that would be pushing it.

 

Generally speaking the folks I talk to about this stuff would say that around 1200rwhp the stock crank flexes.

 

That's kind of what I figured would occur. The cranks are strong, but there are going to be limits. I really would like to see that 1000 RWHP number eventually, though.

 

You'll max out that 7875 long before you ever get to 1,000whp.
If I had to guess, it'll probably be all done around 800whp.
There is always the Mighty Mouse special, wanna say it was a 91mm compressor cast wheel, 96mm turbine but in a T4 housing.
A friend of mine has one, it's a big SOB lol.
There's always a T4/T6 adapter which will open all kinds of possibilities.

 

Oh, I know this turbo won't hit the number and neither will my injectors/fuel pumps. I figure down the road I'll upgrade everything once the car is sorted out and I'm used to the power, lol.

 

1,000whp sounds cool don't get me wrong but with stock stuff based on the people I've talked too starts to be very problematic.
For me personally I'm looking to stay in the 800-900whp range which outta be within the limits of the factory block and crank albeit close to the edge.
I think the combo you have even with the turbo maxxed out is great for a killer streetcar with a manual.
A T4 or T6 with a slightly larger turbine would help it RPM better, maybe a S476R with the 88mm turbine.
@RonSSNova runs something similar on his car which seems to work very well.

 

When I first got my '67 together I was making 14 lbs and making hits on the highway. It was intense lol. If you have a lot of gear and are on hard tires you might have some traction issues.

 

I can relate lol.
Now I'm excited to see what 20-25lbs. brings.

 

I’m around 1000 with the linear power deliver of a Procharger and gets stupid on the street. This is with 15” wheels and 275/50/15 Et street R tires. I will not even drive the car without either my drag radials on or my Stiff wall
slicks on it anymore.


ETA: I’m on stock ls3 block and stock crank with forged rods and pistons for about 5 years now. I started with a D1x at 14 psi and now with an F1a-94 at 20 psi for the last couple years.

 

1000rwhp should be a very safe range for that. Just be conservative with timing and you should never even lose a head gasket. I ran a stock LS3 cast crank, Compstar rods, Wiseco boost pistons in an LS9 block and made 1000-1200rwhp shifting at 7500rpm for years and made easily 100-150 passes around 200mph (1/2 mile racing) and more 1/4 mile passes than I can count (street/strip).

 

Yeah my personal experience @The ****** anything over 600rwhp I needed to always run a drag radial or slick on the street.

On the street I was rolling into boost only hitting 14 about the time I'd get out of it lol. Last time at the track I made 18 1.2 ramp and it went 5.6@127 in the 1/8, probably 900rwhp @ 3200 raceweight?

 

Are you making around1,000whp or chp?
People get hung up on rwhp numbers (myself included) and forget to realize 800whp through an auto equates to about 1,000 at the crank which is still pretty nuts for a streetcar.
Kinda why I elected to keep it around 800-900whp instead of going for the 1Kwhp mark for now.

 

Oh for sure, my last car was setup for auto crossing so zero weight transfer, had a 200 treadwear street tire on it and at 700whp it was kinda dangerous, hence why the guy I sold it to wadded it up in less than a month.
Totally agree you gotta have a sticky tire and working suspension for anything at or over 600whp on the street.
I was pleasantly surprised that I could make full rips from 40-150mph on the street at 14-15lbs. with a fairly aggressive boost ramp with very little drama with my current car.
Good tires and the previous owner spent the time getting the suspension pretty dialed in thank goodness.

 

I really only want 1000 at the wheels as a hero number, I'd never try driving it on the street at that level. But it would be fun to have that at the track. So far, this thing has blown my mind with how hard it pulls, and it's only been street tuned and I'm only running on the wastegate spring. Although whatever spring came with it is pretty nuts, because when I went to the track, I saw 18PSI at the top of 4th gear. I'm going to get that out of there and put a lighter spring in, then set up a CO2 actuated system. After I've got that installed and a few other items dialed in, I'm going to take it to Baker Engineering for a dyno tune to see what I can get out of it.

 

Never been on a dyno. All I have is trap speed and vehicle weight calculators which say it's a hair over 1000 rwhp. This is with a 4l60e and stock differential with a spool. LOL. Just a 377 with 10.6 to 1 static compression and 232/248 cam spinning the procharger to just over 80,000 rpm impeller speed (max recommended is 74,000). E85 and meth injection. I think the blower could actually make more power if I had a more effecient engine. Seems like normally an F1a-94 can make around 1200 rwhp at 80,000 rpm impeller speed.

 

Nice, I'm going to have Baker do my forged shortblock, going to drop it off next few weeks.

 

Same, I just wanted the 1Kwhp for d__k measuring lol.
You can do it though, there's a handful of street race guys around here with 1Kwhp manual cars who are really fast but even then, most of them run around at 700-800whp most of the time.
The road you're on plays a really big part in it too, with that much power you have know the road you're on really well if you put the hammer down, almost learned that the hard way with this car lol.

 

That's where suspension, tires, tuning, etc come into play. The linear power delivery and pulling timing where necessary with slicks on makes everything much more manageable on the street. I've got weight bolted in the rear also. I found the additional weight bolted in the rear did a lot for me. That and giving up on radials because streets, no prep, and bracket prep is all I ever get to run on. I would trap faster with radials "if" I could make a clean pass, but far too often I would blow the tires off and abort the run because radials wouldn't recover. With slicks the car is way more consistent, predictable, and I run a faster ET with a little bit of spin.

I still want more power and planning a new combo with an F1x shooting for 1200 rwhp through the auto trans. I've been 5.9x in the 1/8th but need to run 5.7 or so to be competitive in a daily driver class that runs in the Iowa, Illinois, Missouri area. I'm doing this around 3800 lbs with driver as well. I think the class is actually called weekend warriors or something like that.

If you don't care about ET that much or don't drag race at all then 700 rwhp is a good place to be for something that is just a street toy.

 

I really want a 9 second pass out of this thing, so 700 at the wheels isn't going to cut it. But yes, I definitely need to do some suspension work before I can even think about putting any amount of power down. This car has never 60 footed well, even NA. 1.82 was the best it ever did. Going to do a drag anti-roll bar and a set of double adjustable coilovers up front to start with, the rest of my suspension in the rear should be up to the task. And definitely spend a lot of time tuning the combination.