now that is some serious shade tree mechanic work. Looks to be well done.
Is the TRD supercharger really that bad for the 4.7? (2 Viewers)
- Thread starter Gassiper
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Can you describe or list parts that you used? What is your intake spacer to account for the intercooler height?
Yes I needed 1 inch more of clearance to let the air flow contour thru the air hat for the supercharger. The inter-cooler is a little over 1 inch thick. I put 1/8th inch thick 3/4 inch wide aluminum lift frame under the inter-cooler to allow for more surface area of the inter-cooler to be used other wise it would tend to just blow thru the center part of the inter-cooler. The factory air hat has some inter-cooling to it with a little honeycomb design built into the underside of the hat, plus the 9th and 10th injectors spray the in coming air going to the impellers with evaporation leading to more cooling effect. There is a temperature sensor I put in the 1 inch spacer plate that will monitor the compressed air temp. This all has to be super reliable as I will be pulling a trailer with it from the Midwest to the Arctic circle. It will be in a 2004 Lexus GX470 with 35 inch off road tires. Turns 1800 rpm at 70 mph in 5th gear automatic tranny.
I ran into a little problem with the cam speed sensor. The 2005 uses a different cog on the intake camshaft. It has a 3 wire sensor verses the 2 wire sensor on the 2004. So to use my 2004 computer to keep all the wire harness the same I had to machine the 2005 cog different to fit the 2004 tang style for the 2 wire pickup. I will wire the oil control valves that control the intake cam timing to separate pulse with modulators so I can manually adjust the timing I want for maximum torque or fuel economy. This also may allow some bleed off in boost if needed with the 11:1 compression. It gets far more complicated to switch the wiring harness etc. and switch to the 2005 computer even though I have those parts sitting on my shelf. I just wanted those oil squirters on the 2005 block to cool those pistons down LOL.
I also ported and polished the heads while bringing everything to Toyota specs. I wanted to find sodium filled exhaust valves but had trouble finding anything cost effective. Amazing these Toyota 4.7 V8s! The 2005 I tore down to build this had 110,000 miles on it. Cylinder bores mic perfect to factory specs with honing scratches still showing. The exhaust valves did have some very small pitting which lapped out to perfection. Toyota uses such tight tolerances it is amazing which I hand matched with all my work. One thing I was somewhat surprised with is the factory Toyota full floating rods & pistons. Toyota has such tight tolerances with the wrist pins that all the pins only turned on the rod journals and were frozen from oil gum film in the piston journals so they don't stay full floating for long. This is why I use only the best full synthetic oil to stop this from happening.
I am using this piggy back computer which seems to work great. Map-ECU3 Fuel and Ignition Control - UNIVERSAL - https://urdusa.com/map-ecu3-fuel-and-ignition-control-universal/
I ran into a little problem with the cam speed sensor. The 2005 uses a different cog on the intake camshaft. It has a 3 wire sensor verses the 2 wire sensor on the 2004. So to use my 2004 computer to keep all the wire harness the same I had to machine the 2005 cog different to fit the 2004 tang style for the 2 wire pickup. I will wire the oil control valves that control the intake cam timing to separate pulse with modulators so I can manually adjust the timing I want for maximum torque or fuel economy. This also may allow some bleed off in boost if needed with the 11:1 compression. It gets far more complicated to switch the wiring harness etc. and switch to the 2005 computer even though I have those parts sitting on my shelf. I just wanted those oil squirters on the 2005 block to cool those pistons down LOL.
I also ported and polished the heads while bringing everything to Toyota specs. I wanted to find sodium filled exhaust valves but had trouble finding anything cost effective. Amazing these Toyota 4.7 V8s! The 2005 I tore down to build this had 110,000 miles on it. Cylinder bores mic perfect to factory specs with honing scratches still showing. The exhaust valves did have some very small pitting which lapped out to perfection. Toyota uses such tight tolerances it is amazing which I hand matched with all my work. One thing I was somewhat surprised with is the factory Toyota full floating rods & pistons. Toyota has such tight tolerances with the wrist pins that all the pins only turned on the rod journals and were frozen from oil gum film in the piston journals so they don't stay full floating for long. This is why I use only the best full synthetic oil to stop this from happening.
I am using this piggy back computer which seems to work great. Map-ECU3 Fuel and Ignition Control - UNIVERSAL - https://urdusa.com/map-ecu3-fuel-and-ignition-control-universal/
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Woww, that’s a pretty impressive setup. Did you fab that aluminum riser/spacer? If so, how much would that cost? I would like to copy your setup on my 2004.
Yes I made my own spacer plate out of 1 inch thick aluminum. I just bought 2, one inch square bars I think 12 inches long and 2 one inch thick 4 inch by 16 inch plate aluminum and machined these to fit with my mill. I made finger joints to join the 4 pieces of aluminum locking them together with epoxy and pins. Lay the pattern out on the aluminum from the hat or supercharger plate. I have no idea what a machine shop would charge for this.
You could also buy a single plate of aluminum to machine from but this seemed unnecessary to me. There are so many bolts holding the hat down it will never move or leak it is simply locked into place. The one inch spacer gives you plenty of room to drill the holes for the 5/8 inch copper tubing coming thru the side. You will have to buy 1 inch longer bolts for the hat also. I also removed the regular style bolts inside the supercharger and counter sunk flush mount Allen head bolts so everything was flat and level to mount the inter-cooler. I will have to get you the part number of the oil cooler that I used from Amazon. I used a Bosch water inter-cooler circulating pump and a 2 quart aluminum (cool looking) tank with a heavy duty heat exchanger to go in front of the all aluminum 4 core radiator. All those parts came from Amazon and were not that expensive.
I recommend using only Cometic head gaskets since the race engine builders I know say their experience has been these hold up to high boost and combustion pressures better than others. I think they cost me $200 on Amazon as well. If you are interested in the Rods and Pistons I can help with details on how to get these and set them up.
You could also buy a single plate of aluminum to machine from but this seemed unnecessary to me. There are so many bolts holding the hat down it will never move or leak it is simply locked into place. The one inch spacer gives you plenty of room to drill the holes for the 5/8 inch copper tubing coming thru the side. You will have to buy 1 inch longer bolts for the hat also. I also removed the regular style bolts inside the supercharger and counter sunk flush mount Allen head bolts so everything was flat and level to mount the inter-cooler. I will have to get you the part number of the oil cooler that I used from Amazon. I used a Bosch water inter-cooler circulating pump and a 2 quart aluminum (cool looking) tank with a heavy duty heat exchanger to go in front of the all aluminum 4 core radiator. All those parts came from Amazon and were not that expensive.
I recommend using only Cometic head gaskets since the race engine builders I know say their experience has been these hold up to high boost and combustion pressures better than others. I think they cost me $200 on Amazon as well. If you are interested in the Rods and Pistons I can help with details on how to get these and set them up.
That’s a pretty cool DIY engineering setup. I’m not sure I have the gumption or tools for that at this point. I don’t plan on doing much towing or significant hauling with my rig. However, my front + rear steel bumpers add quite a bit of weight and my “overland” gear and sleeping platform are also heavy. I’m running 33” tires, but toying with the idea of 35’s if/when I get my Eaton rear diff installed. It would be nice to have some more ‘oomph’ traveling through the mountains at interstate speeds, which is a good part of why I would like to add the supercharger ….. besides just fun. I do some offroading and light rock crawling and it makes me a bit nervous to have forced induction without an intercooler.
As a long-winded aside, I knew a guy with a street rod who repurposed his stock AC system as an intercooler for a biturbo LS motor. According to his claims, his IAT’s went from 120-ish on his air-to-water intercooler down to roughly 70f and he was able to run higher boost and better more aggressive timing. The ~20hp parasitic loss of the compressor + electrical fan draw was well worth a giant increase in power with denser air charge and better tuning options. As with most modern AC systems, it also disconnected the compressor and fan at >70% throttle, so no loss while racing anyway.
Which thickness of cometic gaskets did you go with and why?
Have you done anything to your transmission, diffs, or axles?
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Any idea what boost you will try to spin the TRD to? Oversize crank?
Also, are you going to be running 1step colder plugs with a smaller gap?
Yes I am running colder plugs with smaller gaps and plan to only run what the factory pulley setup makes for boost. It may make more boost than I think because of the 11:1 compression. I saw this effect on 2 identical ford Coyote V8 engines one with 9:1 pistons the other with 11:1 pistons both with the same supercharger setup. The 11:1 made a lb or 2 more boost. I have a link to that article which was well done. I guess there is some backup effect that happens. I want the higher compression from an efficiency aspect and torque increase. I used the Cometic 0.040 Gaskets which I believe is the factory thickness and that measured 11.1:1 compression. Those gaskets are made from 0.03 to 0.08 inches thick so you can adjust the static compression the way you want.
I went thru all the current designs on V8 engines and tried to implement all the things modern designs have to offer. So I was able to do Water to air intercooling, piston cooling oil squirters, Long tube Doug Thorley thick wall headers, low restrictive exhaust system, VVT on the intake valves with manual control, higher compression lower friction coated pistons with better combustion chamber design, polished combustion chamber exposed parts, ported and correctly surfaced valves and heads along with more precise engine management control with the ECU3 piggyback.
The newer design V8s have sealed chain in oil designs for turning the camshafts. This being less proven for durability due to chain stretch and plastic polymer disintegration of the chain tensioners. With Audi having its chain back of the block by the bell housing....what a pain to service!! I have one of those twin turbo Audi V8 designs in a car. I hope it never goes bad! At least with this front belt design you can easily service it and no oil leaks.
Another advantage to the 4.7 Toyota is the heads are narrower than many other 4 valve per cylinder designs. I saw a 5.7 Toyota totally fail due to a broken valve spring. It dropped the intake valve and just destroyed that cylinder. And yes, I checked to see if my 4.7 engine build was an interference engine with these new pistons if perhaps my timing belt breaks. There is NO clearance the valves will hit the pistons if this happens! You are as good as your weakest part lol.
I went thru all the current designs on V8 engines and tried to implement all the things modern designs have to offer. So I was able to do Water to air intercooling, piston cooling oil squirters, Long tube Doug Thorley thick wall headers, low restrictive exhaust system, VVT on the intake valves with manual control, higher compression lower friction coated pistons with better combustion chamber design, polished combustion chamber exposed parts, ported and correctly surfaced valves and heads along with more precise engine management control with the ECU3 piggyback.
The newer design V8s have sealed chain in oil designs for turning the camshafts. This being less proven for durability due to chain stretch and plastic polymer disintegration of the chain tensioners. With Audi having its chain back of the block by the bell housing....what a pain to service!! I have one of those twin turbo Audi V8 designs in a car. I hope it never goes bad! At least with this front belt design you can easily service it and no oil leaks.
Another advantage to the 4.7 Toyota is the heads are narrower than many other 4 valve per cylinder designs. I saw a 5.7 Toyota totally fail due to a broken valve spring. It dropped the intake valve and just destroyed that cylinder. And yes, I checked to see if my 4.7 engine build was an interference engine with these new pistons if perhaps my timing belt breaks. There is NO clearance the valves will hit the pistons if this happens! You are as good as your weakest part lol.
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I saw some articles on the rear end (3.71 gear ratio) not holding up on 2004 Lexus GX470. Mine has 175,000 miles on it and it seems to be perfect with Amsoil lube in it. Now I don't plan to bang gears or bind the wheels up with hard abuse. The torque will be distributed between both front and rear axles. I will continue to look at this but gear failures I have had where mainly how I loaded torque onto that failed gear.
I have an issue with this at the moment. I installed everything correctly I believe but when the ignition switch is in the on position it starts spinning the starter and will not stop until I unhook the battery? Any ideas out there? The solenoids in the fuse box under the hood buzz so they are being engaged and once engaged they don't disengage until the battery is disconnected (even with the ignition switch in the off position). Some type of ground feedback loop? Thanks for any ideas on this.
Just an idea. Have you tried hooking up a mechanic’s manual under-hood starter switch to see if that makes any difference?
I would have thought that the E-controlled start systems would either sense when the starter is free-spinning or auto shut off after several seconds.
I haven’t every dealt with the GX starter or anything with the automated-start systems that we have, but I have dealt with several old style starters on other vehicles. I have had starter solenoids that buzzed/clicked and sounded like they were functioning, but either lacked enough oomph (got old and wore out?) or had some sort of physical barrier that prevented the gear from popping out. I also had a s***ty situation with an old Subaru when my flywheel mysteriously lost some teeth in two opposite regions and I would have to get it to rotate a little bit to allow the teeth to engage if it stopped in the wrong position. Fortunately, that one was a manual, so getting a slight nudge was pretty easy.
I’m curious what the final diagnosis is.
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Thanks for the post and ideas on the starter issue. I am trying to get time to get it resolved. I got side tracked now and bought a new Lexus GX 550 Overtrail. It will be fun to compare the old 470 to the new 550!
Any real world data on the performance of that DIY intercooler?
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