[Rlhay2]

Guitarmaggedon does not yet have the fuel capacity to make use of the built block and those large turbos. What he has accomplished thus far could also be done with a stock block LT4.

I was seriously considering the Hellion system with different turbos. Precision's quality control is hit or miss.



And it should be expected that an OEM trans would have difficulties with 950+ rwtq.

The Hellion kit with Xona rotor 62 or 64mm turbos with proper fueling should see 1000+ on the stock block.

[7WSM]

This is possibly the most simple setup I have seen that makes major power. Basically if you slam enough air in the engine with the fueling to support it, it's going to make power. Turbos is the most efficient way of doing this. People really want to over complicate things on a turbo car. The initial cost of parts are going to be expensive, but if you really break it down compared to a properly built supercharged car to achieve the same power, it might be a little cheaper in parts and labor to do it like this then a blower. With a blower, not all of them that I have seen make power like this, it's so hit or miss on the mods. You don't need fancy stroker, heads, cam with a turbo car. Just lots of boost and lots of fuel. The LS guys have been doing it for years and the new 5.0 guys have been doing it too.

[SSE 4 2SS]

Originally Posted by TMac2254

Let me start this out with I’ve been out of the fast car game for sometime(2010 was the last days). Last vehicle was a 02 WS6 with a Procharger so I’m not completely ignorant haha. Now that I’m back and with my new purchase, I’ve been researching and trying to decide on going with a different/bigger blower (Whipple or Procharger) for my ZL1 or a twin turbo system. Been looking over the last few weeks at Turbo systems and the only one I can find is Hellion.

I think I want to go twin turbo but I’m not seeing too many ZL1’s with that system except one guy. After watching several of his videos it makes good power but he had to move a ton of stuff around and he has a built block. Looking for anyone who has this system or maybe knows someone that can give me some real world advice on this twin turbo system. I’m not looking to build the bottom end of this car. Everything I’ve read the LT4 should have not problem handling 1000rwhp. Really wondering why not too many people go this route? Thx in advance for your advice/opinions.

Just like the early 5th Gens, the blower guys jumped out there and led the way.... Buy a cheap blower and bolt it on.... Make 450-600 hp, depending on the boost. Then there was the problems of enough fuel, drivetrain upgrades etc.... The exact same thing is happening with the 6th Gen, be it an SS, or a ZL1, or a ZLE....

There are people that will jump on the band wagon to be out there first, and then those that will push the limits.... It has always been this way....

Now, to go from a blower car (ZL1) to a turbo car may be a bit more work, but the end result will/should be amazing.... The trade off is trading off the existing blower which will help offset the cost of the intercooler, the intake manifold and the cost of the turbo kit.... It certainly wont cover it, but it will help offset a bunch.... You already have a bigger fuel system than the SS guys have.... You already have a long block designed for more power than the SS... You already have the drive train designed for more power.... And, it's mostly unique, as most everyone has a blower.... I'm looking to buy a ZL1 1LE, and I'll leave it stock and drive it almost as my daily.... I know, heaven forbid.... I'll put more street friendly tires on a spare set of wheels, and I'll install a more dust free brake pad... My car, my way.... I've been that way for a while....

Originally Posted by BlaqWhole

The pros and cons will always be similar when it comes to turbo action.

Pros: No parasitic power loss. More power to the ground boost for boost. The power delivery is more linear and doesn't drop off. Coolness factor. Sound. All pros.

Cons: Cost. Complexity. Install and tuning time. Maintenance...when something goes wrong it can be timely and costly. Reliability.

I'd say it is up to the individual owner as to whether the pros outweigh the cons. But I'd imagine that the simplicity, cost effectiveness, reliability, and such of blowers just make them the more desirable path to take. Plus I wouldn't trust just any ole tuner out there with turbos. I'm not sure who I'd go to for the tuning.

One thing I notice is that a lot of systems require fabrication of some sort. Some times a little and other times a lot. And I've seen cases where people have had their car out at a shop for months getting the system installed and tuned. It is a lot to got thru and deal with but a lot of people feel like it is worthwhile. My caution to you would be to do a lot of research on it before you even attempt to go this route. This is an expensive car. And despite whatever is advertised, I can see a turbo system costing $15K - $20K when all is said and done. That might just be my pessimistic side talking tho...

Less parasitic loss, 10-20% as compared to 45-55%... leading to more power per lb of boost....

Properly sized turbos will deliver power based on the desired power goals.... Small turbos deliver power quicker, almost as quickly as a blower, but they run out of top end steam as the size/efficiency wall is reached.... Bigger turbos wont run out of power on the top end but they take longer to spool, though that can be addressed as well.... (two step, small shot of nitrous to spin them up).

For road racing, I would tend to go with a slightly bigger turbo to keep the IAT's down, and to provide a smoother, though larger, power delivery.... For drag racing, and streetability, consider a smaller turbo as they spool faster.... Now if you are looking for an all out race car, then by all means go with bigger turbos, and plan on building the motor to handle considerably more power.... as well as the entire rest of the drive train...

Bottom mount turbos make for a great sleeper.... The only giveaway something is up under my hood is the large pipe feeding the homemade sheetmetal intake.... unless you know what to look for.... I've had people at car gatherings ooh and aah at simple blower cars parked on either side of me, look at my car and walk on by, nothing to see, when I'm sporting 1300+ more RWHP than the blower cars....

The simplicity of the blowers is true, depending on desired power levels.... A bolt on turbo kit, will generally net at least the same as a bolt on blower kit, if not more, and then adding more power can be more or less complex.... Turn up the boost, with a boost controller can be done from the driver seat.... You cant change pulleys from the seat while running down the road.... Blowers can run hot, and you use nitrous, intercoolers, ice boxes, or meth to control the temps, just like in a turbo car.... Smaller harder hitting turbos will tend to heat up more than bigger slower spinning turbos.... My 67/66's made huge heat in mile passes, and we were overspinning them with a 427, causing failures... where my 76/75's ran very cool, and made huge power with incredible reliability....We made 1400 RWHP on spring pressure, at 14 lbs.... We made 2000 RWHP at 27 lbs of boost, and we could turn it up to 35 lbs for a time.... for an estimated 2300 RWHP... (Only an estimate)

As for the cost, that depends on how much power you want.... Sell your intake and blower off the ZL1, and then use that to help pay for the turbo kit.... Hellion builds premium starter kits, usually all inclusive, with minimal if any fabrication is needed.... This includes both the top and bottom mount kits, for the 5th and 6th Gens.... They may or may not have a top mount for the ZL1 yet.... I haven't looked... So, depending on original kit price, and sale price of the factory blower, you might be in the 7500 to 15000 range, or you may end up in the 100,000 plus range.... Ask me how I know....

Originally Posted by JB'sZL1

And in a nutshell, that's it: $20k for a tt (vs 10k in a Gen 5). Plus the reliability and introduced heat issues.

Again, this depends on the kit original price, the sale price of the blower, the power goals, etc.... My original kit for my 5th gen cost me over 30 grand when it was all said and done.... I could have been in twins for less than 8,000 if I had bought and installed the kit myself... However, I pushed beyond the 7 lbs of boost it was geared for....

Reliability is just as good as a blower kit.... This is an old myth.... It boils down to properly designed built and installed systems... There are huge numbers of turbo powered vehicles worldwide.... both gas and diesel.... As for the heat issues, yes, there is a hot casing under the hood, and there are exhaust manifolds under the hood as well.... My car runs way cooler now, both under the hood and in the cooling system than it did when it made less than half the power... Proper design and utilization....

Originally Posted by RDBill

I would just like to add that the turbo ZL1 is also having transmission problems. Because the trans is so new the aftermarket hasn't beefed up the trans yet to handle the big power these cars can make

I am not familiar with the ZL1 you speak of, and so I don't know if it's an automatic or standard trans... If it's auto, then you are probably very correct, though I'll bet there is an auto that will handle the power, but if you push the limits you have to upgrade everything.... eventually.... You will break the weakest link... always, beef it up and go find the next weakest link.... I've done this to every part of my power and drive train for nine years.... It's how we made 2000+ rwhp.... that I can drive on the street, though I opt not to due to fuel mileage.... <3 at idle around minimal throttle, and 5 gallons to the mile at WOT....

Originally Posted by Sakudog

I went Twin Turbo on my 2013 ZL1 M6, it was a massive upgrade over the blower. I did all the work myself and spent a lot of time perfecting the platform. The end results were really really good, 1077 rwhp / 1029 rwtq. (lots of videos here: )

The sounds, the experience, the THRILL of having 4 digit power was incredible!

Pros:
Insane Power
Beautiful V8 Twin Turbo Sounds
Very unique car

Cons:
Lots of upkeep, tinkering, even with 20 years of experience, it will always need a clamp tightened here, a hose moved or adjusted there.
ZERO return on investment, ZERO, don't do this if you want any money back on your TT system, most people are scared to buy a car that has gone through this transformation. Returning it to stock is really not an option because so much is changed/modified to install the systems


Hope this helps!

All well stated.... and correct in the return on investment.... Turbo cars are tinker heavy.... depending on the build, if mild, then very little maintenance over regular maintenance is needed... Keep good oil in it, change it often, put gas in the back and turn the key.... Push the power, and you will be tinkering more....

Another possibility, is to install the turbo kit, keep the blower kit and as long as you don't push it, swapping back may be an option then sell the turbo kit with a factory refresh on the turbos..... This only applies to a bolt on kit.... A custom kit or a car pushed beyond the base kit, Sakudog is absolutely correct...

Originally Posted by mdmoore23

Turbo'ing this platform seems like a huge hassle. Guitarmageddon makes good power with his but you must remember he has a good relationship with a shop close by doing all the work, and probably for little to no money. This makes a huge difference in a case like this. Going with the more common and proven setups may be the best bet.

Some folks like to be different. I could have bolted on a blower kit, and had lots of fun, but I wanted to be different.... Peak performance from any build is a hassle... Moderate performance is moderately a hassle.... etc...

Originally Posted by Rlhay2

Guitarmaggedon does not yet have the fuel capacity to make use of the built block and those large turbos. What he has accomplished thus far could also be done with a stock block LT4.

I was seriously considering the Hellion system with different turbos. Precision's quality control is hit or miss.

And it should be expected that an OEM trans would have difficulties with 950+ rwtq.

The Hellion kit with Xona rotor 62 or 64mm turbos with proper fueling should see 1000+ on the stock block.

Hellion has historically built a great kit... and I run precision turbos, and have had great luck with the properly sized units... with the undersized units, I left a trail of parts down a few tracks... Again, it all boils down to proper design and use...

[JB'sZL1]

Originally Posted by SSE 4 2SS

Reliability is just as good as a blower kit.... This is an old myth.... It boils down to properly designed built and installed systems... There are huge numbers of turbo powered vehicles worldwide.... both gas and diesel.... As for the heat issues, yes, there is a hot casing under the hood, and there are exhaust manifolds under the hood as well.... My car runs way cooler now, both under the hood and in the cooling system than it did when it made less than half the power... Proper design and utilization....

A lot of great insight and info SSE 2SS!

Just for clarification: I have had turbos for decades on my trucks. I did not mean to insinuate that turbos in general are unreliable blast furnaces. I meant that installed tt's on the LT4...even the LSA is largely on untested grounds (compared to stock or even modified blowers). I meant one venturing into tt's for their ZL1 (pushing the envelope over 1-1.2 k rwhp) should expect some quirks, maintenance and possible reliability issues, if for no other reason that no tt system on any ZL1 has been through the proving grounds as blown ZL1's (when compared miles to miles).

That said, a thoroughly engineered, deliberately installed tt LT4 could very well be low maintenance and reliable. I stand by the +$20k figure, as most folks here will not being doing the swap themselves, and, I imagine, most folks considering a tt for their LT4 are seeking 1k rwhp, if not more.

Again, thanks for the post: lots of great response, info and insight.

[TMac2254]

Thanks everyone that has responded to this thread so far. Gives me a lot to think about. As far as a tuner and if I run into any walls if I go with the turbo system, I’m close personal friends with the owners of Underground racing. Wish I could afford one of there Lambos and then we wouldn’t be having this conversation...haha. Kinda wish there was more options out there as far as turbo kits goes, to compare them, hellion seems to be the only complete kit I’ve seen.

[SSE 4 2SS]

Originally Posted by JB'sZL1

A lot of great insight and info SSE 2SS!

Just for clarification: I have had turbos for decades on my trucks. I did not mean to insinuate that turbos in general are unreliable blast furnaces. I meant that installed tt's on the LT4...even the LSA is largely on untested grounds (compared to stock or even modified blowers). I meant one venturing into tt's for their ZL1 (pushing the envelope over 1-1.2 k rwhp) should expect some quirks, maintenance and possible reliability issues, if for no other reason that no tt system on any ZL1 has been through the proving grounds as blown ZL1's (when compared miles to miles).

That said, a thoroughly engineered, deliberately installed tt LT4 could very well be low maintenance and reliable. I stand by the +$20k figure, as most folks here will not being doing the swap themselves, and, I imagine, most folks considering a tt for their LT4 are seeking 1k rwhp, if not more.

Again, thanks for the post: lots of great response, info and insight.

My apologies to you, and everyone else... No argument was intended... No excuse, but I've suffered three strokes, signaling the end of my "racing" days.... I can be a butt sometimes... I was speaking generally, while trying to cover information for the OP.... I quoted so many so I could look back and see what I wanted to comment on....

You are absolutely correct in the mile to mile comparison, and the lack of people that have pushed the limits.... and yes, to go 1K plus RWHP, you are looking easily at probably 20K + (without going into the short block) before its all said and done.... I have always heard and now know that we make a budget, then double that and add a bit more.... So many nickle and dime things pop up...

I have the twins, though it's not a ZL1, and several friends have the ZL1 with twins, though they are so far beyond a bolt on kit.... A pure bolt on kit will allow for a specific growth, most anything beyond that will cause a wallet to thin quickly....