djyankees31

I had a forum vendor perform the LT4 supercharger install. When I received the Corvette back it had the normal connection between dry sump and intake tube. However, the Corvette had issues and the vendor picked up the Corvette to resolve the problems. When it was returned, the intake and dry sump connections were capped.

So why would these be capped to get the Corvette running better?

What is the primary purpose of the connection between the intake and dry sump?

What are the dangers of leaving it this way?

Thanks for your input.




Dry sump capped



Halltech intake capped

Bruce_K

Im curious about this. I cant have the same setup and I cannot manage to get the PVC system correct. Im be scared to have that capped off since i believe thats the fresh air breather side.

djyankees31

Thanks Bruce.

How about all you engine builders and tuners.

How about helping me out with some information.

Much appreciated!

David@MMS

in my professional opinion there is no good reason for that if it is otherwise to oem spec, i would hope there is more to the story. if you can show here or send description of all your connections that would be most helpful

here is the oem routing

djyankees31

David thanks for taking the time to help figure this out.

When the Corvette was returned it had the OEM hose connected between the dry sump and intake. However, the Corvette was running so bad the tech asked that I try capping the two connections to see if it fixed the issues. It did not so I re-connected the hose. The Corvette was trailer'd back to the shop and when it was returned 2-3 weeks later it returned this way with no explanation.

Please see the many pictures that will hopefully help you figure out the setup.






See small red arrow. What should be connect there?



See small arrows. connects to catch can





Small arrow show it connects to a catch can

David@MMS

there is not a visible intake manifold connection so you are not running a pcv system. that explains the rest.
*unless there is some connection maintained between the valley plate and the floor of the manifold*
if you can get that verified then i would rule out the vent setup affecting your tune since no new air is entering the system and being vacuumed to the manifold

that being said there is absolutely no reason to not run a pcv system on such a nice car IMO. it probably stinks and your oil is getting dirty more quickly than normal

djyankees31

Eddie@weapon-x,
Please explain why my build was done this way? I'm sure Blake and Chris can supply the details if needed. As a reminder, when I took delivery of the initial build it was setup with a hose connected between the dry sump and intake. The connections were not capped.

On the second go around, the Corvette was returned with the capped connections and no mention of any changes except for the headers removed.


I've checked with Matt and Mike, both of their LT4 supercharger conversions were done like OEM LT4.

So why was my build done differently?

What about "*unless there is some connection maintained between the valley plate and the floor of the manifold"? If so, please explain how it works.

Would this cause some of the issues I'm having:
1) low vacuum and power assist brake failing when driving in stop and go traffic.
2) really high intake air temperatures?
3) really high manifold air temperatures?

David thanks for you insight and help!

I've been searching for answers for months.

sales @ WXM

Looking at your build list, you have a single open atmosphere catch can mounted.

If you have a vacuum leak somewhere, you would have low brake boosting; however, you do have a camshaft as well, and the cars you're comparing to do not.

Which values are you logging for intake air temps?

Manifold air temp is calculated.

Nothing from your PCV system is going to cause higher IATs, if anything, not drawing the hot air into the intake tube would result in lower temps.

djyankees31

Thanks for responding so quickly!

Yep, I aware of the single open atmosphere catch can. But are you saying with the catch can the OEM PVC system is not needed and the stage 2 camshaft is part of the reason? How does fresh air get into the system now?

All the other LT4's with a catch can still maintains the OEM PVC setup. So why was it changed to this setup when it originally was setup as OEM. At least with the connection from dry sump to intake.

I'm logging all the normal PID's in hp tuners for IAT, IAT2, MAT, Ambient air, and so on. I have a good handle on the various PID's. I've tried wrapping the radiator hoses, putting heat shield on the Halltech intake, sealing the airbox, and etc. But nothing helps with any of the temps. IAT usually runs 50-60 degrees hotter than ambient and MAT accordingly based on the calculated with ECT, IAT, and etc. But still in the 170-190 range during a 20 minute cruise. The pump is running the whole time otherwise the MAT's run identical to ECT for the 3 minutes.

I see guys on the forum with Z06 posts showing their IAT's are always around the ambient temp. Mine is never close. Also the ambient temp climbs 30 to 40 degrees during the cruising to which I can't figure out.

Thanks and appreciate your feedback.

David@MMS

i agree that the vent hose arrangement is unrelated to your tuning / temperature concerns, and is acceptable based on the type of catch can used. there are many ways to skin the cat. weapon x knows what they are doing, so i am sure it was a conscious decision based on some criteria.
my systems were over a month delayed earlier this year and some people who would normally have had it could not fit that in their schedule (for example).

a camshaft will usually change manifold vacuum availability, which is the boost your brake booster gets... however on c7 there is an electric pump more than capable of keeping vacuum up, provided the check valves are in place in oem arrangement. on my car my brakes are not even hooked to the intake manifold anymore.

pn your data logging; it is summer and i cant say from here if data 'across the internet' may be at all comparable to what you are doing with your car.. but maybe it is, but i always put a heavy filter on what 'some other guy said online'. there is not much to go wrong with the system. you either have a blockage / pinch hose or you dont, pump is running or it is not, air bubble / low liquid volume or it is good. heat is just the sign of the beast with lt4. there is also a little bit of fudging getting the lt1 computer happy with the lt4 sensor information, so it could be a simple as some scaling mod or sensor part number used.

hope that helps!

djyankees31

Again thanks David for your input.
I believe your initial comments are on the money before you found out the vendor was Weapon-X. "in my professional opinion there is no good reason for that if it is otherwise to oem spec."

"i am sure it was a conscious decision based on some criteria". I don't agree that it's okay. It's my car and I wanted the factory setup and any changes from factory spec needed to be decided by me. I wasn't given the choice. Also, just because a vendor has a good reputation doesn't mean they always do things the right way or don't cut corners. I went with the LT4 supercharger over the 2.3 because for the OEM look. Now I don't have the OEM look and not even sure how's it working.

I know Weapon-X know their stuff that's why I choose them and drove 500 miles from Charlotte to Cincy. However, I do want to know how the Corvette is setup and why the choice was made to do it this way which is different than all the others seen. Also, the initial Weapon-X install was done the OEM approach. It was just never mentioned to me it was changed on the return and for what reason. I want to be able to put it back to OEM spec.

I just don't want to be on the track, pushing the car and boom because of the setup! It's always good to have multiple eyes on important things and a discussion.

6.2Blown

djyankees31

Weapon-X, Eddie or Ben,

I know it's fathers day and have a wonderful time with you families. But maybe tomorrow you guys can provide the details.

I would like WX to provide a detailed write up of how it was done and what changes are needed to get the PVC back to OEM spec. Take a look at the routing diagram that David provided, that would be great to see something like that.

Why was the change made on the return shop stint and never mentioned during work or after delivery?


If needed, I can create a detailed build thread so more people can assist on figuring this out and to understand the other aspects of the build. Everyone is always fascinated by build threads.

Thanks

sales @ WXM

Eddie is no longer here, and I was just trying to help the other day when I received notification and looked in our system. If you would like more detailed info, please CALL the shop and ask for Blake as he is not on the forums and you have never talked to him on the forum, but he is expecting your call. He and Chris said they would be more than willing to discuss this.

Also, I believe you're leaving out why the car was running terribly after you had it back and had to come back to us. The notes from last year say your Chinese eBay header warped at the flanges and caused the car to run terribly after the fact. We tried to work with you as you were over your budget, including picking up the 1200 mile round trip transport for only $300 to diagnose the issue when it should have been 5 times that (and we didn't end up billing you for the difference despite it not being a result of our parts or work), offering you cost to swap the OEM manifolds back on at a discount, etc.

I also see your power output was dialed back as a result of going back to the OEM manifolds, but again that is something that is a direct result of the parts used. The previous engine build happened as a result of the condition the motor came in and this is the first stock long block C7 we've seen with tattered up cam lobe, so it was a surprise to us all. It sucks to go over budget, but it's pay to play in this industry, yet despite that not being a result of anything we did.You keep comparing your results to the other guys, but I also so a dyno graph of your power vs theirs and it was still much greater, given the correct mods. Blake said if you would do the headers later, you could get the original power back, as discussed.

It seems we have worked with you a lot to help get around some unexpected issues the that were not a result of our sold parts. Lastly, when you call in, please update Blake on the last payment due as well as there is a note on here from accounting. So, please call the shop to address both concerns, thank you!

djyankees31

This is not about bashing Weapon-X or any of their employees. All of them have been very nice either in person, via email, or on the phone, especially Aubrey and Chris. It's about this threads topic and related comments from Sales@weapon-x. If you are interested in knowing my perception of the facts then read otherwise just stop here.

=================

Ben or Blake, why become an attack dog and make it personal when it was a simple thread seeking help on the Weapon-X build of my Corvette. I didn't even mention Weapon-X as the shop until I couldn't get a reply from Weapon-X but only from David at MightyMouse catch cans. Even after that I was respectful and patient. Also, I'm not interested in calling and talking with anyone.

I just want to know the information about my build. Simple as that. So an email will be fine or this thread it's up to you. It's either something I can do as a DIY or I'll take it to RPM in Raleigh. Just want to know the facts before deciding.

On May 30th I sent an email to Ben and Aubrey, subject "Questions, Update, Issues, and Feedback". The email was polite and I thought the information would be useful to Ben as he was not around during my build. On June 13th, I received a very polite email from Aubrey stating the family has been on vacation.

I'm glad you all had a wonderful time. I'm sure it was much needed.

Here's a piece from Aubrey's email: "I will forward this to Ben to reach out. Unfortunately, my expertise ends at accounting, so I am not much help on the technical side of things. I know he’s been slammed catching up as well, but we will be in touch next week. I’ll schedule a meeting with our shop manager (Blake) to review your email as well."

By the way, I haven't heard from either Ben or Blake.


Without putting the whole email for the world to see, the email included a few build and quality issues including tune feedback and possible hardware exchange or refund.

There's a reason I never did a build thread. My perception of the build would not have helped WX business. But maybe the opposite and have turned other interested customers to look for other shops.


Now to address your comments:

Maybe or maybe not. The headers were installed touching the steering rack. Every time I turned the steering wheel it pressed and rubbed on the headers. I sent the pictures as soon as I got the car home. In a 500 mile trip that's a lot of turning. There's no doubt the gasket was roached from the pictures. I believe a contributing factor was the pressing of the steering rack. However, the Chinese eBay headers are not warped in any way. The picture provided and posted in the forum is just misleading. I immediately checked the headers as soon as I received the car back and the headers are perfect. No warping. If you like, I can post the pictures. Go back a closely look at the pictures that was posted about cheap headers. The ruler isn't even touching the two ends. My ruler lies perfectly across the header with 0 gap. Both left and right headers. But that thread did serve a purpose of good advertising in the forum. If anything the Corvette ran like crap because a combination of an exhaust leak from gasket, really bad tune and maybe PVC setup. The tune was reviewed by many professional tuners on HPTuners forum. All replies advised so bad as not to drive Corvette.

Topic at hand --> Why was the PVC routing changed?


Much appreciated! But I was never going to send the Corvette back to Cincy otherwise as I mentioned that. I was planning on carrying it to RPM in Raleigh to diagnose and fix. I wanted to give WX a chance to determine and fix before another shop looks at the build.

On the journey home, I was fortune it made it the 500 miles. I was in communication with Eddie the whole time with the various issues. He was in touch with Blake, Chris, and Jeremy. I still have every email and text that was sent between me and Weapon-X. It would make for good read for any bored members. But it might scare a lot of people from ever considering doing a build.

This thread made no mention of dyno numbers or power. I haven't since December 2017 while trying to understand the difference in actual HP/Torque versus what Eddie and Jeremy thought would be based on the setup.

Why bring this up now? It has nothing to do with this thread which is the PVC difference from OEM and the original WX setup.

Besides the cheap eBay headers, I supplied the LT4 supercharger, LT4 injectors, LT4 fuel pump, and misc parts. Weapon-X supplied the labor, Cam Kit, lifters and rods, forged piston, CAI, tune, wideband, ngauge, and misc conversion kit parts.

Again I appreciate WX allowing me to pay off the remaining $1857 from a WX accounting mistake and the $551.91 from the Corvette pickup and diagnosis. The $2408.91 was being paid back promptly every month over 6 months. Payment 6 of $401 was being delayed until I heard back from Ben or Aubrey. Aubrey made no mention of the $401 needing to be paid ASAP in her June 13th email as my email had discussions of a refund or exchange. I was and am waiting on Ben to reply according to Aubrey's June 13th email.

So in short, Weapon-X charged $15,131.16. I have paid $14,730. Payment of $401 or refund for installed parts is in question.

My main concern is the quality of the build and understanding any changes from OEM that was not discussed. PVC changes were never discussed.

djyankees31

Weapon-X, Ben, Blake, or Whomever,

Where is your customer support???

As of today, no email or detailed response in this thread. It's really wrong and bad business that I cannot get an answer to how the PVC system was done on my Corvette from Weapon-X.

Weapon-X is creating and responding to threads all day and everyday. However, WX chooses to not provide an answer to me via thread or email.

A shame on any vendor that will not provide the details of a build to the customer!!

When you do something wrong, admit it and help get it corrected.

Don't attack and deflect, just do the right thing.

Potential Weapon-X customers, pay close attention to this thread!!

Bruce_K

Honestly, I would try and get it setup as close as possible to the C7Z PVC system. I did this install my self. I can send you pictures of how mine is setup.

djyankees31

That's the way it was by WX originally. So there must be a problem since they removed it when the Corvette was returned. I believe just by connecting the intake and dry sump I will have some of the same issues as before WX removed it. That's why I need to know the complete setup before taking it back to the C7Z PVC system with catch cans.

vettebuyer6369

djyankees31

However, it's a real problem I am seeking help from the community. Weapon-X made it about them since they replied to the thread but would not provide an answer via email or this thread. They attacked me and deflected but like politicians do all the time. Now look, it worked for them. I have no answers to valid build questions.

I paid them a lot of $$$ to be able to confidentially track my Corvette but I can not. They did things other builders would not and did not discuss with me. Now I'll have to spend more $$$ to carry the Corvette to another shop and have it worked to get the PVC system working and to examine the other work performed by Weapon-X.

This thread getting moved does me and the community injustice. It confirms to Weapon-x, build as the please with no responsibility to the paying customer.