[KingLT1]

Originally Posted by JSH

Which stock cars does/did this blower come on?

ZR1 and GT500 come with 2650's.

[JSH]

Originally Posted by radz28

Do you have the standard RF on there?...

RF?

[KingLT1]

Roto fab...

[JSH]

Originally Posted by KingLT1

Roto fab...

Hennessey's 5"

[radz28]

Hmm... If I'm not mistaken, Hennessey uses RF... And that looks like the smaller one. Big Gulps don't neck-down like that to 103 TBs, unless your TB is bigger. Is your a bigger TB?

I'm trying to show Hennessey's CAI and stock TB in the top (2) captures. Those are taken straight from their website videos. Focus on the MAF part of the tube. It's not easy to see, but notice where the bolts go through the heat shield? The tube is pretty much completely round, around the bolts. There is a fair taper to the smaller OEM TB, too.

The third capture is a video from CSP's car where they installed RF's standard CAI and NW 103. Notice how the TB coupler is about the same size on both ends, and that it doesn't hardly taper-smaller to the 103 mouth? The OD on the 103 is about 4" or so. Then, focus on the tube closest to the bolts, too, is pretty much round, just like in the captures from Hennessey's videos. Everything is almost exactly the same for both CAIs.

The 4th is a picture of one of our cars' CAIs. Notice a couple things:

• The MAF tube is large enough that the bolts require recesses into the tube, because it's a 5" (I think that's the size - it's bigger than the standard 4" RF)
• The 5" tube continues thorught the elbow to the TB flange. Notice the RF flange larger than the TB? That's a 103 TB.

I only ask because if that IS a true 5" - nevermind. If it's not, you might have a restriction there. You're going so far as to jump to a 2650 from a great 1740-port, so I suspect you want to keep the inlet-side as efficient as possible. If you don't have a 5" tube, I'm positive you're shooting yourself in the foot by keeping it, and not upgrading to at last something like a Big Gulp.
Your install pics' suggest to me you have a 4"... Just trying to be helpful

[JSH]

Originally Posted by radz28

Hmm... If I'm not mistaken, Hennessey uses RF... And that looks like the smaller one. Big Gulps don't neck-down like that to 103 TBs, unless your TB is bigger. Is your a bigger TB?

I only ask because if that IS a true 5" - nevermind. If it's not, you might have a restriction there. Just trying to be helpful

Yea, it's not a Big Gulp and that's a NW103. We're not sure at this altitude that we'll be restricted for air or fuel, but we'll see.

[radz28]

Originally Posted by JSH

Yea, it's not a Big Gulp and that's a NW103. We're not sure at this altitude that we'll be restricted for air or fuel, but we'll see.

Sorry. I was responding while you were, lol.

I'm only going to add that CSP saw something around 20-WHP, only upgrading from the standard to a Big Gulp, with literally no other hardware changes, all SAE for any corrections. That was 760 to 780 with only the BG (and corrections) - no other changes. I just thought, with your building likely making more power, maybe that would be a good upgrade.

[JSH]

Originally Posted by radz28

I'm only going to add that CSP saw something around 20-WHP, only upgrading from the standard to a Big Gulp,

We're going to finish this build and dyno and road test it to see what more it wants in air and fuel, and I agree a larger CAI will likely be a good piece to start with.

Update: We ordered a Big Gulp today because we concluded we had somewhat underestimated our intake air needs with the porting. The current CAI might work otherwise.

[EDFHOBBIES]

Originally Posted by JSH

It's too impressive to not share

I think I was the 1st ported LT Edelbrock maybe Rabbit was but I know he did the 1st few by hand then scanned them to put into a program for the CNC machine.

Looks like a lot more material removed and more of the rotors exposed. I've gotten a few fb messages about my setup and the other aren't at the level I'm at with a 8.3 lower and 3 upper but, I'm sure camshaft and tune may have something to do with it as well.

LOL I was told not to share but that was a long time ago... I hope your build goes awesome and you put down good number and fast times!

With the testing I did with Vararam the intake tube size was just under 5 inches for the best velocity on his stock looking box with a bell inside the box using a flat filter. Its hard to believe that covid killed the 6 gen production on hos design he hasn't been able to get companies like green to make a filter to fit the boxes with the correct pleat pattern.

with a 112mm and 5 inch intake expect big gains but u need plenty of fuel lol!

[EDFHOBBIES]

Originally Posted by KingLT1

There is no free lunch. Extreme Porting compromises structural integrity of the casting. Which is likely why these companies don't port them out further. They design the blowers to last 100k + miles. Most customers that port them will likely never put more then 25k miles on the setup. So the potential longevity compromises will go unnoticed. Now a light port job that cleans up casting flash and what not probably won't weaken the casting, but excessive porting such as the X port 1.74 can.

I have 20k on it so I'm almost there. I beat on all the time just not at the track!

[EDFHOBBIES]

Originally Posted by JSH

He says an additional 50-100 hp depending on blower rpm, and he should know since his cars are often on the dyno.

The 100 hp will come from a 112mm and the big gulp along with a few more rpms. the biggest problems is the inlet restriction which you fixed with porting and the next biggest problem is feeding the inlet the 112mm or larger TB and 5 inch will fix this.

If you could use the copo intake see pic (vararam designed it and gm had it made of carbon) you would honestly crap yourself.. i probably just got Patrick in trouble.


the biggest hurdle is feeding any blower with the 90 elbow right in front of the TB the next biggest hurdle is cool air in that area where the big filter fits which does it no favors this is what pat worked on for copo they gave him a cfm number something crazy and it wasn't possible to to make it with how the intake is setup on the 6 gens.

all though not beautiful his designs really work a no filter or flat filter will beat a cone filter everyday of the week. hopefully the country(s) will get back to work some day.

I did some testing with a his filter and box that was 3d printed just before covid I picked up 48 hp over the BG rotofab. Next month after he sent the 3d printed box covid happened they were able to get 1 sample made but it needed some attachments relocated and the area needed to be enlarged to grab air down by the fender liner to meet the cfm demand. He hasn't got a nes sample back yet with this covid crap for me to finish up fitment and report all the gains.

[radz28]

Yup. It seems like feeding the fronts of these are at the top of the priority list if you want to get every little bit out of them. LMP's 2650 build (like the COPO style) had a huge mono blade, directly fitted to the oval snout, and was putting out huge numbers.

It seems like that Kong port's evolving some, and that's great. Tapering that bearing block seems to be the biggest difference in the pics'. Pretty cool.

Hopefully you get somewhere on that Vararam. I remember you talking about it a while back now.

[KingLT1]

Originally Posted by EDFHOBBIES

I have 20k on it so I'm almost there. I beat on all the time just not at the track!

Sweet...glad it's holding up!

But just to clarify...The kong Maggie or Eddie likely is not ported to the degree of a X port stock blower. Some have reported race ported stock blowers flexing. Hence why I said a mild port and clean up on these larger blowers likely is not an issue. I was only speculating why the Manufacturer doesn't clean up the casting flash and what not. Perhaps they don't feel the potential gains are worth the extra time and effort before packaging them up...dunno.

[JSH]

Mechanical work is done and we're hauling it to Fort Collins to tune/dyno. [Wonder how far off it will be at startup] I'll post more pics later. Had to notch the hood to fit the Eddie