Limits?

**slims00ls1z28** · 02-12-2015, 04:42 AM

I'm in the planning/buying stage on my Camaro. So far the LQ4 is in the machine shop. Finished bore will be 4.040. I ordered the Dragonslayer stroker kit with the compstar H-beams with ARP 2000's and weisco forged pistons. I also have the ARP main stud kit. I plan on spraying with a progressive kit. The question is with my combo what limit should I set for this engine Hp wise. Eventually I will go LS7 top end custom cam etc. but it's not in the budget right now. I want to know theotetically what can this bottom end take on a an occasional basis with my parts list.

***SMWS6TA*** · 02-12-2015, 05:56 AM

I wouldn't look at max hp rating at this point, I would just be ball parking it. Too many factors to try to account for.

Seeing how 408ci can easily get into the 500's depending the cam, heads and crank I can't see why you can't.

Some other things you need to consider.

Cam & Heads - try to get them spec for the build. That much bore lets you handle big cam's. You might be in the LS3 cam's now. Valve Springs at going to need to be match the cam. Learn from me, have a shop set them up. It's easy to just trow them on and think you're good, but I learned from mine that there's more to it then that.

Fuel injectors & pump - Both of these are going to need upgrading if not already done. I have 42lbs for my build but may need to bump up some when/if I do a nitrous add on later.

Tuning - It comes down to the tune. A good tuner can squeeze every bit of HP/TQ and keep it safe for the motor, a bad one can make it under-power or worse help destroy the motor. Start looking for one.

**slims00ls1z28** · 02-12-2015, 07:47 AM

I was esitmating 500 crank or close to it with my set up N/A. Would love to be able to spray 3-400 to it put that should put it close to the 800-900 hp range (with better injectors, pump, heads etc. not any time very soon). That's the benchmark I want to hit with the bottom end, but be safe to the 1K range when I get my LS7 head (or better) setup going. My builder is saying that with the LS7 heads and a cam to suit 600 N/A is easy, so adding 300-400 (progressive controlled) would put it in the 1K (theoretically of course). Just want the bottom end built for it now because that is the hardest to replace. So I want to make sure there's nothing else I need to throw at it at this point in just the bottom end. I'm going ahead with the Wiseco upgraded pins as well.

I have a racetronix 255 and 42# injectors for now, but pretty sure they will need upgrading when I finally do spray it. The tune I shouldn't have much trouble with as I know a few guys that are willing to teach me the ropes on that and I already have HP tuners. I won't touch anything on it or spray it until I've had all that done first.

The big kits will come but as long as my bottom end is built for the future I should be good until then with a little 150-200 shot or whatever the limits are on the single nozzle wet kit I have now. I would just hate to get to the big boy leagues and have it come apart because of something I didn't get that I should have for what I plan on doing.

Still have a long way to go till I hit what my goal is, but trying to plan as much ahead as I can. 4L80E is in the works and the current Moser 9" should be good to go. I have a steel driveshaft so I hope it'll be good to go (for now only) too. I know I don't need the 4L80 or 9" or even the dragonslayer for my current iterration but want to know that at 1K, provided everything else with the tune, fuel, heads, etc this kit should be fine barring the usual mishaps (which follow me like the plague).

***SMWS6TA*** · 02-12-2015, 08:30 AM

For that much laughing gas you're going to need appropriate rings and bearings. Otherwise you fry them and then have other issues. And you are also looking at a double fuel pump, something that will come on when you need it.

Estimate about 15-20% for drive train loss and that will be a rough idea of RWHP.

I'm wondering if destroking the crank and getting a high rpm crank would be better for you instead of 4" crank. I was reading that by doing so it works very well for boost and high nitrous builds. But that would be something you need to talk with a serious race engine professional.

**2002ssslp** · 02-13-2015, 05:49 AM

Whatever you do please have the machine shop balance the rotating assembly. The harmonics in an unbalanced engine will magnify as the HP goes up. Add some spray to the mix and you will have a very short running life to this motor. Average price for a good balancing is about 250.00

***SMWS6TA*** · 02-13-2015, 06:49 AM

^^^^Truth!!

Mines is at the shop now getting this done.

And if you smart ask them to set up the rings and pistons as well.

**slims00ls1z28** · 02-13-2015, 12:22 PM

Yep already being done. The seller asked me if I wanted the kit balanced and I opted out because my builder/machinist will do it. He already knows I'm spraying so he said he'd set the rings up for spray as well. I'm letting him do the bottom end to take out any guesswork and anymore problems like I just went through. Hes going to bore, line bore, balance, install cam bearings and assemble rotating assembly, filing the rings and setting them up for nitrous. Here's hoping all the guesswork on the rotating assembly is out of the equation.

***SMWS6TA*** · 02-14-2015, 10:14 AM

one more suggestion since you plan on spraying that high, Make sure you have ARP 2000 rod bolts and that they use a stretch gauge on them.

**2002ssslp** · 02-15-2015, 05:35 PM

Originally Posted by slims00ls1z28

Yep already being done. The seller asked me if I wanted the kit balanced and I opted out because my builder/machinist will do it. He already knows I'm spraying so he said he'd set the rings up for spray as well. I'm letting him do the bottom end to take out any guesswork and anymore problems like I just went through. Hes going to bore, line bore, balance, install cam bearings and assemble rotating assembly, filing the rings and setting them up for nitrous. Here's hoping all the guesswork on the rotating assembly is out of the equation.

Looks like you have all the bases covered. Good luck with the build.

**35th-ANV-SS** · 02-15-2015, 06:25 PM

Depending on how much power you make NA, you might need to look at upgrading your injectors prior to spraying. 42#/hr will support 500hp, but if the motor makes 600, you'll be looking at a 90+% duty cycle. Last thing you want is to starve the motor of fuel. A second note - I have read that 550rwhp is on the brink of what the 255 walbro can support. If anyone else has additional information on this I'd be interested as I'm also running the walbro pump.

***SMWS6TA*** · 02-15-2015, 06:25 PM

one more thing.....get a good oil pump.

Melling 10295 or 10296

**Naaman** · 02-16-2015, 03:27 AM

Oh... the cycle of parts and labor... mine turned out much more expensive than I was prepared for as well...

**slims00ls1z28** · 04-29-2015, 12:02 AM

Yes I upgraded to the arp 2000 rod bolts and bought the melting pump, so got those covered. I'll just run it as is until I get bigger injectors don't think the trans will hold anyway with spray just yet. Wife and friend are leaning on me to just go with a glide and forget the OD. Sigh all the choices, time to start banging out some overtime. That new msd airforce looks really good as well.

***Ed Blown Vert*** · 04-29-2015, 10:23 AM

Originally Posted by 35th-ANV-SS

Depending on how much power you make NA, you might need to look at upgrading your injectors prior to spraying. 42#/hr will support 500hp, but if the motor makes 600, you'll be looking at a 90+% duty cycle. Last thing you want is to starve the motor of fuel. A second note - I have read that 550rwhp is on the brink of what the 255 walbro can support. If anyone else has additional information on this I'd be interested as I'm also running the walbro pump.

Have you considered a Racetronix Pump. I run their dual system.