Long story short, people following my recent build know that I am doing the FAST 92mm intake, LS2 90mm TB, and 5 pin 85mm MAF swap. I currently have a K&N intake on my 99 coupe it looks like it will be the restriction now. The filter has a 3.5" outlet, and the Air-bridge has a 3.5" inlet. (This matches the stock 75mm MAF that the older cars have.)

I'm sure it would be as simple as obtaining the kit for a later model that would have the diameters matched to the 85mm MAF. But I'm not about to order one without knowing for sure and not really willing to pay for another K&N intake new...

So basically what Im looking at here is obtaining an air-bridge and filter with larger diameter inlets and outlets. This way I can run a 3.75" ID straight coupler 2" long from the filter to the MAF and from the MAF to the air-bridge. Instead of screwing around with finding proper fitting reducers, (which is not looking good). They are all 3" long. And they are necking down to the old diameter which means they are now the restriction.

I found out by looking at filter numbers that the filter I have has an 89mm outlet and the LS6 style filter has a 98mm outlet. I cant find any info on the difference between the air-bridges, but Ill bet the later one has a larger diameter too.

So I guess with the 85mm MAF I can go with any intake I want, but I will have to order as if I have a later model car to get the size that fits the 85mm MAF . It might be a good time to go with a Vararam B2 system... Still undecided.

What to do? Any suggestions? I really do like the K&N and wouldn't mind upgrading to the later style for the right price.. I could always try to sell my current intake setup..

 

Couldn't you just move the MAF to the outlet end of the air bridge, closer to the throttle body?

 

No, surprisingly the outside diameter of the LS1/6 TB is close or the same as the LS2 TB. The inside is obviously very different. But the air bridge has a 4" outlet that matches very well to the LS2 TB. So not even the 85mm MAF will sit between the two without needing reducers.

 

I'm interested in what you come up with. I'm doing away with my MAF and going with a speed density tune. I also want to go with a larger diameter airfilter and connection to the air birdge. I still have the stock 2000 LS1 throttle body, coupler and air bridge.

Will the larger diameter air bridge fit the early style coupler (throttle body to airbridge) or are you changing that as well?

 

Yes it will, but the front side of the air bridge will not mate up to the 85mm MAF, nor will the 3.5" diameter filter to the MAF. But I think I am just going to order the K&N intake for the LS6. It will match up to the parts I am going with. I wasn't able to boar out the air brige enough to make a smooth transition from the MAF. The bridge has too undersized of a diameter and impedes flow.

 

You really have no idea how many CFM each of these parts you are putting together actually flow.

It just could be that the TB with the blade in the middle of it flows the least.
Ditto for the MAF.

Wouldn't it be fun to put each on the flow bench and see?

 

So I got a hold of the instructions that come with the different part number intakes. All three designs of the K&N intake for the C5 show 3.5" x 2" couplers to and from the MAF. But if that was the case, the air bridge and filter could not be a larger diameter... But I know that the filter is due to looking it up by itself by part number.

This makes me very hesitant to but the kit. Did not all 2001 and newer base and Z06's have the 85mm MAF? The instructions are all different and clearly for that particular system, as well as the parts list. Why would the couplers be measured at 3.5"? I measured the 85mm MAF I have, and 3.75" is needed. How do these kits work for anyone with an 01 and newer C5?

I already spoke to K&N directly about this whole ordeal. They were no help

 

The funny thing is, even the kit specifically for 2001-2004 shows the old 3 pin MAF being used in the install... This doesn't make sense.

 

I verified that the later units are legit. Larger air filter outlet and different air bridge part number. I guess the couplers are wrote down wrong. The kit must come with larger couplers for the later models. Otherwise they would never work for customers.

Now the choice is between part number 63-1050 and 57-3035... The only difference is that the 63 series supposedly has a smoother bridge. But again, the part numbers for the bridges are the same in these two kits and they use the same filter. Plus my early model 57-3020 is smooth as glass on the inside... Something tells me they all have this technology now.

Anyone know if the 63 series is worth paying more for? It is supposedly for the Z06 and the 57 series is for the base model. But there is no difference other than the air bridge from what I have researched. And like I said. The kits have the same part number for those...

 

Thought you might find some of this info interesting:
http://forums.corvetteforum.com/c5-t...fications.html

I'm not thrilled with the K&N intake being half way through the radiator cover. I'm looking to keep the filter completely below / boxed in like my old Vortex. Guess the Vortex box could be widened to fit around the bigger K&N filter and something like a 22.5 degree angle fitting to tip the filter down lower.

 

Just an idea here but I went with a C6Z06 intake. I put a kn filter and opened up the shroud to expose the filter more. I have an opening on the rad shroud where the filter sits. The intake is way bigger then the LS1/6 stuff and you can find in the parts section cheap. The opening to the tb is oval but is a lil more then 4in, going off the coupler i needed. Also I had to change to LS3/7 type maf which is an upgrade anyway. Easy to repin and tune.

 

I looked into the C6 style K&N intake and disregarded the idea as it would force me to relocate the MAF. I will check into it a little more though. Sounds interesting. The 85mm MAF that I bought obviously wont fit well between the two pieces and make for a weird setup. Do you know the diameter of the LS3 MAF? I may find it worth getting and selling my LS2 MAF... I know it is a card type MAF and will make the MAF and adapter I bought useless... But it might be worth it.

If it is a 90mm or larger I may go this route. the setup I am close to doing would give me a 98mm filter outlet, an 85mm MAF, a 90mm TB, and a 92mm intake snout. So the MAF is still the smallest point in the intake. The LS2 intake and LS3/7 MAF leading into the TB/intake may give me a fully 90+mm intake...

 

The LS3/7 maf is a card style sensor. It just slides into a slot. They sell the slot so you can mount it on any custom intake and some companies like Halltech even make an intake for c5's with an LS3 maf but its pricey.

 

Ya I finally figured that out.. I was unaware that it was not in its own unit till I looked into it more. I guess that's why I only ever see housings available through various vendors, for custom setups.
The C6 K&N has a slot built in to accept the card type MAF and it is similar in price. It obviously will fit my LS2 TB well.
I guess all Id have to do is slap the new intake on and slide an LS3/7 MAF card in. How is tuning a card type MAF on the LS1? Does it also have the IAT integrated? The C6 intake wont bolt up like a C5 specific one, but I do have the shroud cut out too and Im sure I could get it it sit where I need it to...

 

Its very easy to repin the new maf. Just pull the old ones out and insert to the new sensor. It also has an intergrated iat. Halltech has a schematic on what pins the wires go to as well as tuning charts. Shouldnt take a good tuner more then a few hours to have it all dialed in. Ill try to find the schematics.

 

Don't worry about it man, I appreciate it allot, but I don't think I will go with the LS3/7 MAF the more I think about it.. I will be hard pressed to ever actually out flow a descreened 85mm MAF on a 346 CID engine. Plus, I need room to mount my fanned transmission cooler, so the larger C6 air filters are not going to work for me. Plus I already have the MAF and adapter etc.

Don't get me wrong, it sounds like a great setup, but even the LS6 style intake gives a 98mm filter outlet and very unrestricted system. I think I will be good with it and my FAST intake setup. Car will be seeing heads and a cam, but I cant even do long tubes here in Cail, so the intake will be better than what I need anyway I think.