What I'm having a hard time understanding is how it can make 700rwtq on a stock block? I have heard that this is because turbo's build power differently. What about wear on the valvetrain?
My Questions:
1- So how exactly does a turbo build power differently from a H/C car? Does it kick in later in the rpm range? We all know a car with more hp can lose to a lesser hp car. Is this the case with the turbo? It might make 200rwtq and 100rwhp MORE than a h/c car but will it outrun it on the street as much as the number's are different? Anyone have any dyno sheets we could look at?
2- What are the advantages and disadvantages of turbo's.. do they heat up too fast prohibiting back-to-back runs or prolonged periods of racing? Do they need to be serviced often or at all? Since the install doesn't require going internal or beefing up any other parts aside from the fuel system, I'm thinking they are pretty safe and reliable. Yes?
3- Any power over stock is going to cause wear and tear on an engine/car. What kind of wear are we looking at or is it general overall stress on the engine? Will anything, specifically, need to be addressed over time? What about certain parts that are abused on a head/cam car like oil pump and timing chain. Will those need to be upgraded?
4- With this kind of power is the possibility of throwing a rod or rod bolt likely? Would it be pushing the limit? I would feel uneasy if that was a possibility that could happen at any time.
5- As far as tuning goes, Rob's shop is only a half-hour from my house so if I experience any tuning issues I'm sure I could get them straightened out pretty fast. Will I need to keep tabs on my tuning or once its set, is it in there for good?
6- Why does everyone say this kit is $8k? It is a complete kit for $6500 including the tuning. What else is there that they are leaving out or that will be needed additionally?
Thanks guy's. I'm just checking base on all of this because for a few thousand more I can double the power I would gain over a H/C package.

<small>[ December 10, 2002, 04:14 PM: Message edited by: SStolen ]</small>

 

first off remember that this 9psi on race gas is not what you will see with a the base kit for 7psi and pump gas.

the more air you can get in at low engine speeds the more torque, the t63 spools so fast along with t properly sized tubing/intercooler that the output is just huge!

other than the valvesprings, the valvetrain really is not stressed, that happes at high rpms, not low where this torque is made

the turbo itself has normal wear, nothing big, just check it out every 10k or so to see how things are doing.

wear on the engine is the same as any other increase in output..

at 700rwtq i would def worry about stock rods and bolts, but like i said above, the base kit is 7psi pump gas not 9 on race mix like the dyno you are comparing to.

i would kill to have robs shop a half an hour away ... what are you doing here? go there right now and camp out! tell me when my stuff gets there too! ..seriously go talk to him in person about all of the above, he'll tell you everything you need to know.

once the tuning is right, its right, just do NOT turn up the boost without retune/refueling

only one person says its 8k, hes including installation because he does not want to do it himself.

 

So do you have Rob's turbo kit or are you still waiting for it? Thanks for answering all of those questions. What I'm still wondering is how much faster this turbo is going to be over a big head/cam/headers install. A h/c car has almost instantaneous power where the turbo has lag in it. I know jack about turbo's but what I've heard is that they have lag and you only build up full boost/full power at high rpm's. So how much power is this car getting to the ground over the whole powerband and not just at peak? A h/c car is putting down CLOSE to peak tq as early as 3000 rpm. Thanks again.

 

No! Full boost at 2500RPM. NO H/C combo can match that torque at that low an RPM. H/C cars run up to 65-7200 RPM for their peaky power (BIG valvetrain mods), where turbo cars run to 6000-6200 (stock redline). The turbo makes "table-top" flat torque, where H/C cars big-time lack torque. That's why a foregone conclusion is BIG gears and BIG convertor with any aggressive H/C combo.

Last time I checked, the most aggressive H/C stock-cube LS1 combos (that could be street driven) were making 450-460 (dynojet) RWHP. Those are obnoxious, surging, bucking brutes.

Turbos are docile, almost transparent power adders on the street. Invisible until the hammer goes down.

Hope this helps.

SC-

<small>[ December 11, 2002, 11:48 AM: Message edited by: SS00Blue ]</small>

 

Are there any posts or sights that I could visit to learn more about turbo applications and how they function? And would the timing chain and ported oil pump still be neccesary? Thanks for the help Blue, very reassuring.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by SStolen:
<strong>Are there any posts or sights that I could visit to learn more about turbo applications and how they function? And would the timing chain and ported oil pump still be neccesary? Thanks for the help Blue, very reassuring.</strong></font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">Like the Mouse-ster said, go your LS1 over to Rob's place (LS1 Motorsports) and poke around. The guy is great to talk to, and he's always willing to show a customer around. I would call ahead, though, because he's one busy individual!

If your oil pump works, I wouldn't worry. Most of the cases I've heard were relatively new and limited to earlier years. Mine's a 2000 with 35000, and the pump works perfectly. The timing chain, IMO, is unecessary unless you've changed to a cam with a more radical lobe or higher lift. In either case, it's your call, but I'm not going to waste the effort.

Let us know if you'll be joining us in the FI section permanently.

SC-

<small>[ December 12, 2002, 10:10 AM: Message edited by: SS00Blue ]</small>

 

Blue: Your going to be running 20#'s of boost with the t-76 turbo???? <img border="0" title="" alt="[Eek!]" src="gr_eek2.gif" /> <img border="0" alt="[hail]" title="" src="graemlins/gr_hail.gif" />
What have you done to hold the engine together in one piece?
Your block-> <img border="0" alt="[kaboom]" title="" src="graemlins/gr_bomb.gif" />

 

SStolen - If you aren't too busy this Friday the 13th, come by the shop. We are only 15 miles from the Kennedy Bridge. We have John Roosa's '98 Z28 at the shop, waiting for the weather to break so he can come pick it up. His car has the first full production #001 Turbo kit. I'd be more than happy to show it to you, and let you hear it as well. Unfortunately for you, John is planning to pick it up this Sunday. So Friday would be the only day you could actually see it. I'll be at the shop until 6pm.

Before everyone starts asking....it made 478rwhp at 7.5lbs of boost, on pump gas, at an ultra safe 11.0:1 A/F ratio. It's a stock '98 Z28 with an automatic trans and a Moser 12-Bolt. It made 301rwhp prior to the turbo install. It idles, runs and drives like a completely stock car until you put your foot in it.

 

HES ALIVE! THANK goodness! hehe <img border="0" title="" alt="[Big Grin]" src="gr_grin.gif" />

this car being done is very good news.. to me!

since comparisons are inevitable, the latest ati d1 car made 462rwhp at 8psi and it was a manual vs. this 478rwhp at 7.5# with an auto.
Now you gotta tell me, what was the torque? the ati above made 459rwtq

rob, i have a few lightning quick ?'s should i post them or just call you?

<small>[ December 13, 2002, 06:09 PM: Message edited by: MIGHTYMOUSE ]</small>

 

Unfortunately, we couldn't get a good torque number out of it. Not because it doesn't make mad torque, but because the car has 3.73's in it, and it wanted to downshift nearly everytime we dynoed it.

When we tune A4 cars at Ed Wright's, he locks out the downshift solenoid in the computer, so we can make long 3rd gear pulls beginning at a low rpm. On the car we just did, that wasn't an option since we weren't at Ed's, and we saw 525rwtq at 4800 (that was where we began the dyno pull without it downshifting). Comparing the TQ vs RPM dyno to the original M6 car we did at 7lbs of boost, it looks like John's A4 car is making at least 625rwtq at around 3500rpm's. It has virtually ZERO turbo lag.

They also had a problem with the dyno tach pickup the day we were there. We could only get partial dyno graphs. It would loose signal 3-4 times during a pull, leaving us to try and fill in the blanks. If John dyno's his car later, maybe he'll post graphs here.

I can tell you this, his car has complete BMR suspension, Hal shocks, roll bar, and it's a full weight convertible rolling on 17x11 wheels. And flooring it at 60-65mph results in massive wheel spin all the way through 3rd gear. There is NO DOUBT this thing is making some serious torque.

Hope that helps.

 

</font><blockquote><font size="1" face="Verdana, Helvetica, sans-serif">quote:</font><hr /><font size="2" face="Verdana, Helvetica, sans-serif">Originally posted by Rob Raymer:
[QB]We have John Roosa's '98 Z28 at the shop..QB]</font><hr /></blockquote><font size="2" face="Verdana, Helvetica, sans-serif">is he on ls1tech or ls1.com at all?

if hes not tell him to get on there so we can naggingly ask him some questions when he gets it back instead of you all the time. <img border="0" title="" alt="[Wink]" src="gr_images/icons/wink.gif" />