That was also a concern of mine. I may raising the roof in that area by extening the welded pipe all the way over to open up that area so the case outlet has more room to flow that air. You can see from my pics posted that I did bite into the that area by 1/2 inch and raised the pipe there to get additional flow. My new design would make it all the way over and raise the entire top by 3/8 inch.
Fastest 5.0 (pushrod) Kenne Bell Mustang?
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That was also a concern of mine. I may raising the roof in that area by extening the welded pipe all the way over to open up that area so the case outlet has more room to flow that air. You can see from my pics posted that I did bite into the that area by 1/2 inch and raised the pipe there to get additional flow. My new design would make it all the way over and raise the entire top by 3/8 inch.
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If you have the hood clearance go as high as possible. You want to avoid as many sharp turns as possible and right now that air is making a sharp 90* turn right off of the supercharger. Plus better to overbuild it now than have to re-do it later. Your pushing over 30 more cid's than we are and that engine is going to want to breathe. It is kind of why we went to the AFR 225 head, it gives us room to grow when we go to a 360+ cid combo.
Righto I've had much time to rethink my design and improve and now is the time. I went with the 205 cnc heads because TEA offers a great CNC program for the right price, but than again I could have used the 225cc or even more according to my cam builder. It's always someting and never enough is it. But sure is fun to play 
Where it is getting expensive for us at this point is the rpm's that we are going to spin. Now we are going to have to use Jesel Rocker shafts to get the valvetrain stable. Upon dis-assembly of the engine 2 weeks ago, there was evidence of the valvetrain not being happy at 6,800 rpm and then bouncing on the rev limiter for the last 100 feet of track. Figure the cost of a custom solid roller cam, solid roller lifters and then the valve spring package, plus now Jesel rocker arms, and we do not know yet if we can use the same length pushrods or not. Try to change one thing and it snowballs, but hey, we knew that going in. And somehow I would not have it any other way.
I don't see how you mounted the 2.8L case with the longer Fox snout without going into the firewall. All the measurement I've done show the 2.8 is a 1 5/8 longer and if not moved forward would leave no room for inlet. My plan is to used a shorter 94/95 drive 1.75" shorter than the Fox and move the case forward.
Part of the answer is that back in the day when the car was painted, the engine was out at that time and the seam that runs along the top of the firewall was removed, that right there gave us about 3/4 in of "extra" room. Also the blower case was moved forward a bit and a shorter spacer that is in between the blower pulley and snout was used. Also we "massaged" the firewall to make room for the inlet manifold. Plus the inlet manifold is a custom made, so that may have been taken into consideration. I will have to take some pic's next time we work on the car so you can see.
Just got done reading your dyno thread over on corral, and you have one stout engine. It will get even better if the outlet manifold is changed to allow more airflow out of the supercharger. With that stock outlet you have maybe 2 inches from blower case to top of casting. If the outlet is off of the blower I think that the inside depth is only about "2 fingers" which measuring my fingers is only 1.5". That is not a lot of room to push that much air through. If you look at our combo there is at least a 5" rise from the blower case to the top of the outlet manifold to give the air a chance to make the 90* turn to the intercooler manifold. I do not know how much underhood clearance you have, but you need to maximize this area. Also be careful not to use to thin of aluminum for your modifications. We ended up having to redo the top of our outlet manifold (granted it is much bigger from a sq/in" standpoint) because the pressure coming out of the supercharger caused it to vibrate and crack after a number of passes. That vibration, while bad (cracked the aluminum) did set up a resonance in the aluminum that was unreal. You could hear that supercharger all the way down track, over the sound of the exhaust and everything else. From a sound standpoint it just made you think that you had died and gone to horsepower heaven.
I also noticed an increase in the sound of the KB whine when I opened the side of the manifold. The thinnner wall of the 3" pipe made for like you say a resonator that amplified the sound of the KB whine, and I love it. With my stock hood it's going to be very tight going higher maybe 3/8 inch more. I will be able to make it wider as right now with the 2.1L the bolt holes for the manifold are 3.25 inches apart center to center which limited how wide of a pipe I could use. With the 2.8L H seires my understanding is that the widest bolt spread is 4.75" which would allow alot more air to move through a wider refabricated intake even if the the manifold height is limited. I just measured and it's 1.5" from the mating surface of the case to the inside roof of the KB intake. I can improve on this as well with going 3/8 higher and thinner than the KB's cast manifold I can gain .5" inside for a total of 2" from mating surface and KB case discharge area to the roof of the fabricated intake. And with the wider opening between the 4.75" bolts area and 3.5" pipe I should have a substancial increase in air flow in that area. It's good to know about the aluminum crack with your manifold I'll have to watch out for that.
You may also enjoy my video
Will have to watch the video when I get home tonight, work computers do not allow for video watching. What with the engine getting better flowing cylinder heads, optimizing air flow into and out of the supercharger and into and out of the cylinder heads will be key. I do not think that you should use anything less than 3/32" material in your outlet manifold modifications. The tubing attaching to the outlet manifold is not as critical from a wall thickness standpoint, as there is strength in being a perfectly round tube. What you do have going for you, is your outlet manifold will not be very wide or tall so there will be less issues than what we ran into. I think I read in your build post over on Corral, that you are still using shorty headers, if so there is a lot of HP left on the table compared to good longtube headers. Especially at your HP level, with the new better flowing heads it will be more of an issue. Just as the supercharger is an air pump, and it works best with no restrictions, your engine is just a different kind of air pump that responds just as well to fewer/no restrictions. I may be telling you stuff you already know as you could not have done what you have without some understanding of air flow dynamics. A lot of the reason for our project ending up the way it did was to try to eliminate as many air flow restrictions as possible. That is why from the throttle plate to the screws at the back of the supercharger it is maybe 5 inches, and we race it with no air filter. Our exhaust consists of Kooks stepped longtubes (1-7/8" to 2") with 3.5" collectors and 3.5"exhaust pipes in and out of a X-pipe to 3.5" bullet style (Moroso I think) mufflers and dumping just before the rear differential. We did have to install some Dynatech Vortex insert cones to cut down on the decibel level to conform to the noise restrictions at one of the tracks we race at.
wp331
Member
92ROHCP,
Intake temps are currently running 130-140 on hot days with 20lbs of ice on each pass in the cooler box. My car hasn't been dyno'd in two years. I have found that getting a baseline tune on the dyno after big changes is helpful only to the point of doing a shakedown. As soon as we start making passes large changes in AFR/Timing are required to maximize the ET/MPH at the track. We usually see up to 3 lbs more boost at the track than on the dyno I presume from the ram air effect of 143 mph on the throttle body
I think the max boost on the 2.1 through the intercooler was 16 at the track. The 2.8 gave us another 3-3.5 lbs of boost and god knows how much cfm. We did pick up more than 9 MPH with the blower change.
The height and shape of the intercooler and manifold when using air to water is difficult to package with max performance in mind. When we decided to build the air to water system I was basically told it couldn't be done in a fox body by just about everyone I asked. NOT being the type of person who responds well to being told something CAN'T be done, I basically dug in and DID it. Of course this was only doable with a lot of help from Vernon(bullitt347) and fab work from no less than 3 different shops and myself, two inlet and outlet revisions and the blower change. If someone is going to do a low profile setup that would clear a stock or 3-4 inch cowl hood it would probably involve a compromise in heat exchanger efficiency and hp potential. The height of SBF intakes and the DEPTH of the heat exchanger needed to be efficient at high boost levels are the biggest issue. My initial setup had the k member spaced down and a lower profile top cap with a 3 inch cowl hood. This combo could not flow enough to make real big power. Vernon is leaning toward a one off sbf intake and intercooler core to bolt the blower down in the center of the engine similar to a gt 500 setup. This approach will make a cleaner setup and lower the profile but would likely drive up costs significantly. If a core can be packaged, in this manner,that is as efficient or more efficient than mine it would be the BOMB for KB PR setups.
I really like your air to air setup and look forward to seeing what kind of et's and #'s you get with your upgrages! I can really appreciate the amount of effort and engineering you have put in that car!
Walter
Intake temps are currently running 130-140 on hot days with 20lbs of ice on each pass in the cooler box. My car hasn't been dyno'd in two years. I have found that getting a baseline tune on the dyno after big changes is helpful only to the point of doing a shakedown. As soon as we start making passes large changes in AFR/Timing are required to maximize the ET/MPH at the track. We usually see up to 3 lbs more boost at the track than on the dyno I presume from the ram air effect of 143 mph on the throttle body
I think the max boost on the 2.1 through the intercooler was 16 at the track. The 2.8 gave us another 3-3.5 lbs of boost and god knows how much cfm. We did pick up more than 9 MPH with the blower change. The height and shape of the intercooler and manifold when using air to water is difficult to package with max performance in mind. When we decided to build the air to water system I was basically told it couldn't be done in a fox body by just about everyone I asked. NOT being the type of person who responds well to being told something CAN'T be done, I basically dug in and DID it. Of course this was only doable with a lot of help from Vernon(bullitt347) and fab work from no less than 3 different shops and myself, two inlet and outlet revisions and the blower change. If someone is going to do a low profile setup that would clear a stock or 3-4 inch cowl hood it would probably involve a compromise in heat exchanger efficiency and hp potential. The height of SBF intakes and the DEPTH of the heat exchanger needed to be efficient at high boost levels are the biggest issue. My initial setup had the k member spaced down and a lower profile top cap with a 3 inch cowl hood. This combo could not flow enough to make real big power. Vernon is leaning toward a one off sbf intake and intercooler core to bolt the blower down in the center of the engine similar to a gt 500 setup. This approach will make a cleaner setup and lower the profile but would likely drive up costs significantly. If a core can be packaged, in this manner,that is as efficient or more efficient than mine it would be the BOMB for KB PR setups.
I really like your air to air setup and look forward to seeing what kind of et's and #'s you get with your upgrages! I can really appreciate the amount of effort and engineering you have put in that car!
Walter
Damn it Walter! You are taking all of my spotlight! 
Glad you chimed in though, cause my memory gets foggy (as you well know) from time to time.
Glad you chimed in though, cause my memory gets foggy (as you well know) from time to time.
wp331
Member
Well now, that was out of character for you to be this nice! I was expecting something a little more scathing. But ill take it! I will heap all kinds of verbal abuse on you when we put your engine back together. I know you would expect nothing less from me and my usual wit.
wp331
Member
Nice to hear from you Walter, it's been great sharing ideas here with both of you and you guys have given me some good ideas for the new 3.5" pipe upgrade and integration to the Kb manifold. Walter nice IAT's with your HP and on the track that seems to be working well and keeping heat under control. Now I would like to know what you guys can run for total timing?????
I worked today on mounting my new huge Procharger race intercooler 17x15x3 3.5 in and outs. It's a bear to get hehind the bumper cover and I'll have to do without the front bumper support all together.
I worked today on mounting my new huge Procharger race intercooler 17x15x3 3.5 in and outs. It's a bear to get hehind the bumper cover and I'll have to do without the front bumper support all together.
wp331
Member
No problem. I ran up to 27 degrees total with c 16. Never came close to that on 100 octane and water meth. You will find the intercooler will work better without the fiber glass bumper, it will get better air flow.
That more like it..........you sure about that 27* total timing number? I seem to remember having discussions on race day whether or not 24* was going to be safe or not. Maybe you just fat fingered it! Probably got all excited about busting my chops.
Only data logging air temp after intercooler, The air temp at throttle body is going to be ambient, as the throttle body sees direct outside air coming over the cowl hood. The engine management system is a FAST XFI. At least the datalogging system is XFI. Walter can let your know what model the rest of the system is, but I think it is at least 5-7 years old, and yes it is a speed density, bank fire set up.
wp331
Member
The fast is classic bank to bank with wide band 10 years old..and yes it was 27 degrees of timing
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