ghetdjc320 Posted February 6 Author Share Posted February 6 14 minutes ago, Comanche SS said: If you can rotate or replace that throttle body with a less intrusive style one, you can spin the PS resi, and run a 4'' intake tube around it like I did in my MJ I had thought about flipping the TB but it’s a 3 bolt. My plan is to build similar to the design @USN_JeepMJ used but with carbon fiber tubing for less heat absorption. Also, after cleaning out that ls6 intake manifold, I believe a catch can is in order Link to comment Share on other sites More sharing options...
Comanche SS Posted February 6 Share Posted February 6 4 minutes ago, ghetdjc320 said: I had thought about flipping the TB but it’s a 3 bolt. My plan is to build similar to the design @USN_JeepMJ used but with carbon fiber tubing for less heat absorption. Also, after cleaning out that ls6 intake manifold, I believe a catch can is in order Yeah, along the same lines as what I followed/did. I too have been looking into the benefits of catch cans, all three of my LS rigs need them lol Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 6 Author Share Posted February 6 4 minutes ago, Comanche SS said: Yeah, along the same lines as what I followed/did. I too have been looking into the benefits of catch cans, all three of my LS rigs need them lol I was surprised how much oil accumulates in the intake. I always run a catch can on my watercraft but they are supercharged. Hadn’t seen a NA engine need one. Looking at a nice clean option if I can find one. Chase bays has a nice kit as does improved racing Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 6 Author Share Posted February 6 Just went out to double check and I have right at 4” of clearance at the pinch point between the ps reservoir and the fan shroud. I’m thinking the 3.5 will fit perfectly with a bit of clearance all around Link to comment Share on other sites More sharing options...
Comanche SS Posted February 6 Share Posted February 6 11 hours ago, ghetdjc320 said: Just went out to double check and I have right at 4” of clearance at the pinch point between the ps reservoir and the fan shroud. I’m thinking the 3.5 will fit perfectly with a bit of clearance all around Will you have to scale the MAF sensor to account for that size of tube? I know with my setup, I had a choice to run 3'' or 4'' and the MAF sensor had a reducer to avoid having to scale the MAF in the ECU...not sure how the Gen 3 MAF sensors work though. Mine ran like crap with the 3'' reducer, so I opened it up to a true 4'' tube all the way thru and the tune mustve been setup that way, because it runs flawless now with 4''....The size of the tube really changed how it ran more than I thought it would. Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 6 Author Share Posted February 6 6 hours ago, Comanche SS said: Will you have to scale the MAF sensor to account for that size of tube? I know with my setup, I had a choice to run 3'' or 4'' and the MAF sensor had a reducer to avoid having to scale the MAF in the ECU...not sure how the Gen 3 MAF sensors work though. Mine ran like crap with the 3'' reducer, so I opened it up to a true 4'' tube all the way thru and the tune mustve been setup that way, because it runs flawless now with 4''....The size of the tube really changed how it ran more than I thought it would. This particular maf that came with my c5 engine is made specifically for 3.5" tube afaik. The c5 has the over the radiator oval design on the intake that necks back to a 3.5" tubing then the maf then the filter. I'd love to do something very custom here but the 3.5" tubing looks to be the best bet overall. I am thinking along the lines of a custom airbox though or perhaps even custom intake routing. I'll have to take a closer look at it and see what may work. I do like though that there is plenty of room around the engine for airflow. Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 7 Author Share Posted February 7 Generated a 3D file for the air intake area Also took some measurement pictures 1741998033_Airintake.zip Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 13 Author Share Posted February 13 Slight mods to the ps reservoir bracket to gain some additional clearance. Lowered the reservoir by 3/8" and moved it back towards the throttle body by 5/16". also shaved off 3/16 from the outer edge. May not seem like much but gave me 5/8 more clearance overall between the fans and the reservoir. I also dug up the maf sensor and can confirm that it is for 3.5" tubing. The OD measures out to 3.6". To reduce turbulence and get the best readings, I'm going to mount the MAF about 2" back from the filter then try to keep a pretty straight shot of at least 12" back to the TB where it will use a 3.5-4" bending reducer. The goal is to use plastic or carbon fiber tubing to reduce heat absorption in the tub itself. Also made a small wire frame for the intake area and will try to fab some sort of heat shield and duct. I did look at doing the camaro -2 spacing on the puller to use the holley low mount setup. But I would have lost almost and in of clearance between the radiator and belt drive. And, all the kits that mount the alternator down low on the drivers side of the block tend to use the small case style which I don't want to run. The corvette reservoir location is also quite ideal from the standpoint of fluid delivery to the PS pump. Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 16 Author Share Posted February 16 Modified the SFR crossmember/skid for the swap. The shorter length of the drivetrain does make it tricky to get some items lined up properly. But with enough modification and adjustments it works out nicely. On the sfr crossmember, I removed a section for the transmission mount, then I cut a custom piece from 1/4” plate and welded that in. Then I mocked it up and drilled out the mounting holes for the Novak tranny mount. Made a pair of flag nuts to make it easier to service later. Had to add a nutsert to the MJ frame hole for the factory tcase skid. The sfr unit uses that same factory mounting position. Everything aligned nicely. Need to add a 1/4” spacer to the transmission mount but it’s otherwise all finished. Started on engine wiring as well and got about a third of the way through. I’m keeping the ECU, TAC module, fuse block and relays all under the dash inside the cab. The engine bay looks much cleaner this way. Routing cabling and planning it all out takes time but is very rewarding. Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 16 Author Share Posted February 16 Interesting tidbit of info, the Corvette LS programming in the ecu’s monitor the oil pressure in the data stream and use a nice 5v reference sensor. So I’ll keep the corvettes oil pressure sensor connected and run the Jeep gauge sender off of the oil cooler ports using an adapter. I don’t believe the corvette programming actually uses the data for tuning purposes but I’d like to leave it there for reference and perhaps data logging Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 17 Author Share Posted February 17 Was able to source a NOS 04 LS6 valley cover which has the pcv built into the cover itself. This has much less oil exposure and keeps a cleaner intake. Also eliminates all the pcv hoses that circle the manifold. May do a catch can a well but perhaps down the road as it’s a simple bolt on. Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 24 Author Share Posted February 24 Mounting accessories. This process is tedious but I’m liking this layout. Also swapped to the 04 LS6 spec PCV valley cover and eliminated all the older style system. This will keep the intake much cleaner. Link to comment Share on other sites More sharing options...
watchamakalit Posted February 24 Share Posted February 24 Not trying to be critical of you build by any means but that arb compressor bracket looks like microwaved dog turds compared to it surroundings. That is all I have to add. Lol Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 24 Author Share Posted February 24 15 minutes ago, watchamakalit said: Not trying to be critical of you build by any means but that arb compressor bracket looks like microwaved dog turds compared to it surroundings. That is all I have to add. Lol That was just a test fit. Took a lot of tweaking to get that bracket configured for all the accessories. It now holds the radiator bottle, compressor, ac dryer and relay/fuse box Link to comment Share on other sites More sharing options...
89 MJ Posted February 24 Share Posted February 24 36 minutes ago, watchamakalit said: Not trying to be critical of you build by any means but that arb compressor bracket looks like microwaved dog turds compared to it surroundings. That is all I have to add. Lol Microwaved dog turds! Link to comment Share on other sites More sharing options...
watchamakalit Posted February 24 Share Posted February 24 6 hours ago, ghetdjc320 said: That was just a test fit. Took a lot of tweaking to get that bracket configured for all the accessories. It now holds the radiator bottle, compressor, ac dryer and relay/fuse box Glad to hear it. I was worried you were loosing your touch. Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 27 Author Share Posted February 27 Mountains of electrical and final fitting of mechanical components coming together little by little. Tcase linkage is finished. Also finished assembly of the transmission shifter. I made a thin aluminum plate as a baffle like the nv3550 had in later years to prevent oil slosh from entering the new vent I installed. The ARB breather is now mounted and will vent both axles, transmission and transfer case. Finished up the winch solenoid wiring and got everything routed and terminated. Used 2awg welding cable and copper lugs then installed marine grade heat shrink tubing that is adhesive lined to keeps things sealed. Routing lines, cables and hoses is very time consuming but well worth the effort. I’m also ditching the arb relay and fuse and integrating them into my fuse/relay box and power distribution. The winch control switch wiring, arb harness, and all engine wiring is routing through the old renix ecu firewall plug. The painless bulkhead connector is handling lighting, wipers, horn, oil/water sensors and a few accessories such as the rock lights. Didn’t get many pictures taken today. Link to comment Share on other sites More sharing options...
89 MJ Posted February 27 Share Posted February 27 12 hours ago, ghetdjc320 said: The ARB breather is now mounted and will vent both axles, transmission and transfer case. So do you have lines from each item going to this breather, or does each one have its own breather? Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 27 Author Share Posted February 27 1 hour ago, 89 MJ said: So do you have lines from each item going to this breather, or does each one have its own breather? Lines running from each item to the breather Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 28 Author Share Posted February 28 Link to comment Share on other sites More sharing options...
ghetdjc320 Posted February 28 Author Share Posted February 28 So after having spoken with painless and seen other posts from psi conversions, they are both saying to provide pin 17 on the red ecu connector with the ac clutch signal for idle up. According to the factory diagrams for the corvette, that will need to be a ground signal not a 12v + signal like the ls1 f body vehicles had. Also will be adding an rpm cutoff logic board. The 12v coming from the ac control deck will go to the logic board which will be N/O. The logic board will close the switch below 500 or so RPM and above 4000 RPM. This 12v wire will then continue to one side of a relay trigger. The ground signal will go through the trinary pressure switch, then splice into two and feed the ground side of the relay trigger along with pin 17 on the red 411 ecu connector. The second trigger output from the trinary pressure switch will provide a second ground source for the fan relays. With the AC on, all the fan relays will activate. Link to comment Share on other sites More sharing options...
Limeyjeeper Posted March 2 Share Posted March 2 On 2/23/2025 at 9:37 PM, ghetdjc320 said: Mounting accessories. This process is tedious but I’m liking this layout. Also swapped to the 04 LS6 spec PCV valley cover and eliminated all the older style system. This will keep the intake much cleaner. Don't forget to use silicone around the knock sensor seals. They fail very often and water gets into the knock sensor tube's. There is a TSB on this where GM also recommends making a dam of silicone across the valley cover to stop water ingress. Link to comment Share on other sites More sharing options...
ghetdjc320 Posted March 2 Author Share Posted March 2 1 hour ago, Limeyjeeper said: Don't forget to use silicone around the knock sensor seals. They fail very often and water gets into the knock sensor tube's. There is a TSB on this where GM also recommends making a dam of silicone across the valley cover to stop water ingress. That’s a good point! I’ll add some good sealer there. Couple of questions I wanted to ask you also: What did you end up doing for ac idle up signal? And did the 411 pcm tach output wire work for your tachometer signal without any other mods or was a pull up resistor required? TIA Link to comment Share on other sites More sharing options...
ghetdjc320 Posted March 2 Author Share Posted March 2 Here is the TSB referenced above: https://www.corvetteforum.com/forums/attachments/c5-general-103/what-would-you-pay-for-this-c5-3680571/02-06-04-023a-47899884d1436760407 Link to comment Share on other sites More sharing options...
Limeyjeeper Posted March 2 Share Posted March 2 17 hours ago, ghetdjc320 said: That’s a good point! I’ll add some good sealer there. Couple of questions I wanted to ask you also: What did you end up doing for ac idle up signal? And did the 411 pcm tach output wire work for your tachometer signal without any other mods or was a pull up resistor required? TIA I used the AC request from the Jeep HVAC controls into the 411 PCM. It will then handle the idle and fans for you. The tach output worked fine using the output from the GM 411 PCM Pin 10 Red. Set the Tach output in the PCM to 12v pullup. No pull up resister needed. I never managed to get the speed into the PCM to work accurately even with the Dakota Digital box. Not that I needed it because I am running a manual, it does cause issues for the Cruise Control. It will be a spring job to finally figure that out. The CC ran for a while, when I first did the build but not now. Need to go back to basics. Link to comment Share on other sites More sharing options...
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