Tony @ Mamo Motorsports

Guys,

Just wanted to share some recent developments here that will hopefully save a small percentage of you some future headaches if you purchase and install one of my ported MSD intakes for the LS7 application (and more specifically when installed in a C6Z06).While this situation has been sensationalized a bit on the forums (as things typically do!) there is an issue with a small percentage of vehicles where the rear of the MSD LS7 intake rubs against the firewall with some making more contact than others. The reason its a situation at all is that the location of the firewall depends on the location of the body on the chassis and unfortunately that's not as precise as some of you might think it would be. Keep in mind here that an 1/8" of an inch (or even half that distance) may be all the difference between hitting and not hitting so this isn't meant to be a bash on GM.....I would wager that most car bodies regardless of brand aren't perfectly and precisely located on their respective chassis.This situation besides adding all sorts of unwanted noise in the interior compartment can also penalize you some in performance if it creates false knock and the computer starts pulling timing. Here are a couple of pictures highlighting this situation where a customer of mine removed the intake manifold after it ran briefly suspecting it was making contact due to noise in the interior cabin.








So what I am doing from here forward to greatly reduce the chance of contact back there is to modify the rear of the intake as well as provide a low profile stainless bolt in the bolt boss that could create the potential issue. Here are a few pics to try and give you a better idea of what Im doing......fist one is stock, the second is modified with the original bolt and washer in place better emphasizing how much material I have removed, and the last picture the same intake with the low profile hardware I will be providing in that one location replacing the original MSD bolt that came with the manifold.








I would approximate Im giving you guys at least an extra 1/8" of clearance back there (maybe even 3/16") and knowing that majority of the intakes I ship to my customers have zero issues, I would say I probably eliminated 90% of the small percentage of the folks that might have had some contact with the firewall.Once again just to clarify, this isn't an "option".....if you buy a ported MSD intake complete from me I will include the extra labor and hardware free of charge.

I should add this intake manifold upgrade represents (IMO) the largest HP per dollar mod in the LS7 platform.....on average most of my customers see a 35 RWHP gain.....that's insane for well under 2K ($1595 actually) and is more along the lines of a budget set of aftermarket heads for close to a 1/3 of the cost when you factor in install labor. This swap is half an afternoon in your garage.For those under a rock who haven't followed this mod a great deal, here is an older thread I posted that has alot of good information concerning the upgrade and what you can expect to see and pick up from the swap.

https://www.corvetteforum.com/forums...t-mamo-vs.html

While unfortunately most of you will never know if what I did extra here was the make or break for you, its certainly nice going into the purchase knowing that you will (likely) never have to worry about it.....removing the intake to deal with this is just a major annoyance burning time none of us have



Cheers,Tony

Albert Lowe

Progress

Hib Halverson

Hey Tony-
In the case of an LS7 already equipped with the MSD, can you see the area of potential interference with the engine in the car and the manifold installed?

Using an inspection mirror, maybe?

Albert Lowe

[img]blob:https://www.corvetteforum.com/f27cc5e3-b16c-4ff8-bd8d-099cb254d458

From passenger side.

Albert Lowe

After I clearanced mine

cv67

Attention to detail....good stuff cost$. Keep up the good work.


-SealBustah lol

Tony @ Mamo Motorsports

Not sure about the inspection mirror or not (whether you can get the correct angle) but even an inexpensive version of the tool shown above (inspection camera) clearly gets the job done.

Also you could try a large zip tie.....they are about .080 thick and flexible.....see if you can snake one down from the top of the intake to the bottom in the area you can see from the pictures that could be a potential problem dragging it left to right to make sure it doesnt get stuck or blocked between the intake and the firewall.

Not sure if that method works or not in this application (I use that method alot for checking windage tray clearance when I build a stroker engine) but I figured its worth a mention......alot cheaper than an inspection camera....LOL

Let us know how you make out!

-Tony

CASEWORER

Definitely one of the best bangs for the dollar spent out there. Now if you could just come up with a way to keep the bolts from loosening up which I realize is not a issue on every MSD intake but most definitely a issue on some. I honestly believe if this issue is ever resolved it won't be by MSD but rather someone like you or perhaps probably you. Your dedication to this platform has been a great benefit to all of us N/A guys.

double06

I think another issue is the water pump to front of manifold problem. You have to grind there sometimes. It may be one of these things when you shave the heads it becomes more of an issue.

Hib Halverson

Thanks for the zip tie idea, Tony. I don't have a noise problem so I figure clearance is likely not an issue, but at least I now know an easy way to check.

Should we call that the "Mamo Zip Tie Clearance Checker"

jimbob8915

I never had fit issues with my MSD. The issue I had is like many others an that is the constant maintenance of re torquing. I tried Mr. Mamo's torque method an I would still see it work loose. I wonder if the bolts were in a steel sleeve that just allowed the gaskets to get compressed and not compress the plastic if it would fix this issue.

Albert Lowe

Yeah that would probably fix it. Too many flexing parts as it is now. Could also try some loctite 246. It’s medium strength, but the high temp version. Might stand up better to the heat in the cylinder heads. If you’re really fed up with it you could always safety wire the bolts.

jimbob8915

I truly feel the bolts do not back off but the bolts stretch or the plastic collapses. Does anyone know the size an length of the 10 mount bolts and the bolt grade? If they are stainless that could be an issue. Maybe some harder bolts or a couple of stacked spring washers would help. Not lock washers but an actual disc spring or a “Belleville washer”. 100in/lbs is really about 8ft/lbs a few stacked disc spring washers could do that.

freddyvette

I just torqued them down to 140 inch lbs. Hopefully I didn't break anything, but seems okay?

Albert Lowe

I think that might be too high of a torque for that size bolt in aluminum threads. Valve cover bolts are same diameter and torqued to 105in lbs. If you pull the threads out of your heads that would make for a really bad day.

freddyvette

Ok, I'll back them out to 100.

Tony @ Mamo Motorsports

When you say work loose your saying you have bolts left literally loose or finger tight after a couple of thousand miles of driving it or just not as tight as when you initially installed and torqued them?

Everyone used to say the same thing about the FAST intakes (almost identical construction) and I never had issues with my personal engines or engines I built for my customers.

The key is to really get them all the same torque initially and many passes around the manifold required to do that (as you tighten one the adjoining bolts loosen some). Also use a higher torque value than stated in the instructions (100 inch pounds or slightly more is fine here.....you have a ton of thread engagement in the cylinder head). To be honest I used to simply install these by feel.....granted I have been wrenching a long tome but even doing it that way I never had an issue with my manifold bolts coming loose.

I could say confidently that I ship a dozen ported composite intakes a month.....some months more than that.....been doing that type of volume for the better part of a decade.....that's a crap ton of intake manifolds.....LOL
My point is if every one of my customers experienced this bolt loosening phenomenon I wouldn't have time to run my business fielding calls from customer with loose intake bolts. This situation is still very much the exception and not the norm I assure you but I understand the some folks like yourself are legitimately having problems and I would love to figure out why when its all said and done.

Anyway....will keep thinking about why some folks are having issues and others are not....If I come up with any grand ideas I will certainly hop on here again

Yeah man.....I should patent the zip tie method....LOL

Let me tell you....try checking clearance of a windage tray in a stoker engine that you purposely keep close to the rotating assy....the zip tie deal was a god send and I wished I had thought of it sooner!

Sometimes caveman technology rules!

WICKEDFRC

With so much technology that's advanced since rhe caveman, .how is it that there is no definitive solution to the MSD bolts requiring a retorquing now and then?

Any bonafide solutions like using LocTite or lock-nut washers? .

What's the fix?

Tony @ Mamo Motorsports

I've never used loctite and I have never had a problem going back to the FAST intakes and some folks complaining about this in 2005.

I think the use of either (loctite or a mechanical lock washer) in conjunction with my method of many passes around the intake and insuring the bolts are all the same relative torque would eliminate the situation. In fact maybe using both (lock washer and loctite)....the shot gun approach might make the most sense to the guys that have this nagging issue. I just couldn't fathom the bolts loosening in that situation.....it wouldn't make any sense that they could.

Who is going to try that first? Just requires a 6mm stainless steel lockwasher be purchased....in fact I have them here already for other applications (6mm stainless lock washers) and I will mail the correct quantity to the first guy willing to try this in conjunction with loctite and my method of tightening and report back.

-Tony

WICKEDFRC

Tony,

Looking at the above photos, there are two different sized heads on them bolts.

Would you supply a full set of standard sized bolts or the low profile bolts?

Will adding a 6mm lock washer require a longer bolt?

Almost sounds as if this could be a pre-packaged solution for all your MSD sales to ensure a flawless install regardless of the firewall percentages.

1. MSD Select Bolt kit
2. 6mm Lock-washer Kit
3. Proper Loc-tite