Stock Fuel Rails, why they don’t keep up

[16GoManGoHC2]

So .026 on new rings what were the stock gap? .022?

This was stock gaps as found was around .019” and also the chart recommended in book is .014 to .020 So this is about .007 more then the as found gap and .012” more then the minimum stock gap. Also there’s .300” of piston above the first ring to help keep them cooler. I figure after break in and the cylinders wear in .0001-.0003 that will open the gap up a thou or 2. Recommended for medium boost 15 to 30 psi on E85 is .007” per inch of bore .0285”. Being that I’ll be around 18 psi max, the low end of the range I used .0065” per inch of bore so .0065” X 4.0925”=00266” gap. So I’m only .0025” tighter then what is recommended for 30 psi of boost, I think I’ll be good. Was going to do .028” first but pondered on it a long while and went with .026” on both first and second rings. The second will get no where near the heat of the first and is a much softer ductile ring so it should always have a hair bigger gap then the top ring.

 

[16GoManGoHC2]

Didn’t get to play much today. Measured piston skirts to check piston to wall clearance, 4.088” 1.300” down from bottom of oil ring groove so right at the recommended.005” of clearance. Weighed pistons there where 2 1/2 gram heavier then the others so weighed the pins and put the 2 lightest pins in the heaviest pistons and weighed them with weigh matched pins and all 8 hit the scale at 671 grams with pins. After that it was chores all day getting ready for beach trip to Edisto with the grand daughters!!! Can’t wait!! Washed my and cleaned my 4Runner for the first time this year, changed all 4 O2 sensors and installed just cleaned injectors and changed the oil, vacuumed, windows, hosed down the under body and frame rails. Was a busy day. Not bad looking for 18 years old daily driver in the snow and crap 55 interstate miles a day round trip to work for 226,000 miles now. Needs waxed, hasn’t seen a coat in over a year, still going strong, 4Runners rock!!

 

[Jack_Toepfer]

That Runner is a GEM!

 

[Speedy!]

Great info on the piston weight and ring gaps. I can't remember if I posted this but I went back and looked at the ring gaps from my Arrington built engine in Orange Krush and top was .024 and second .026, so you're right there. It was built for 15ish psi of boost and 1000HP.

Yeah 4Runners are great vehicles. Mine's coming up on 20 years old and I literally have only changed fluids and the front O2 sensor in all that time. 145K miles on mine and it's been supercharged since 60K. Mine needs a complete detail BAD.

 

[16GoManGoHC2]

Great info on the piston weight and ring gaps. I can't remember if I posted this but I went back and looked at the ring gaps from my Arrington built engine in Orange Krush and top was .024 and second .026, so you're right there. It was built for 15ish psi of boost and 1000HP.

Yeah 4Runners are great vehicles. Mine's coming up on 20 years old and I literally have only changed fluids and the front O2 sensor in all that time. 145K miles on mine and it's been supercharged since 60K. Mine needs a complete detail BAD.

Cool, good info, THANKS!! I’ve been on the fence about whether to open them up 2 more thousands or not.

Super Charging my 4Runner has always been a though. What year is yours and what SC is used? Mines a 04 Allot in doing it??

 

[Speedy!]

Mine's a 2002 and back then TRD had Magnuson develop their supercharger for the 3.4L motor. No intercooler due to hood clearance so it had some limits, but I added water meth injection and cranked up the boost to 11psi and it goes pretty good now. Tuning was a bit tricky and required a piggy back and you can't control timing directly but have to give the truck what it wants to give you more. With the water/meth I see 19-20 deg at WOT. I'm not sure what's available for the 2004.

 

[16GoManGoHC2]

Rod Bearings finally arrived, been on order for 3 months. King pMax Black ceramic polymer coated bearings. They are advertised at being .06250” thick, King prides themselves on their tolerances, all 16 measure .06250” thick!! This will put my Rod clearance right at .0013”, right where I wanted it. Hats off to King, Now as long as they work and hold up as good as they look and measure LOL Now to get vacation over with and back to business LOL

 

[BULL]

Rod Bearings finally arrived, been on order for 3 months. King pMax Black ceramic polymer coated bearings. They are advertised at being .06250” thick, King prides themselves on their tolerances, all 16 measure .06250” thick!! This will put my Rod clearance right at .0013”, right where I wanted it. Hats off to King, Now as long as they work and hold up as good as they look and measure LOL Now to get vacation over with and back to business LOL View attachment 45951 View attachment 45952

Do your mics have a round anvil or did you use a gauge pin offset?

 

[16GoManGoHC2]

Do your mics have a round anvil or did you use a gauge pin offset?

.2000” Ball end on the Mic of course!!

 

[BULL]

.2000” Ball end on the Mic of course!!

I've got an old pair of .0001" analog mics with a ball end, but my good Mitutoyo QuantuMike with .00005" are all square jaws.



(An aside, the QuantuMike series are the "fast" pitch thread version. I'm not a fan... Just my preference I guess)

 

[fumanchu182]

I went through all 13 pages to read this journey from fuel rails to engine rebuild. Felt like a novel. Awesome thread! Looking forward to seeing more progress.

 

[16GoManGoHC2]

I went through all 13 pages to read this journey from fuel rails to engine rebuild. Felt like a novel. Awesome thread! Looking forward to seeing more progress.

It’s become a secret engine build thread only for those like you who take the time to read it all!!

 

[16GoManGoHC2]

I'm curious what tune changes for cam timing will look like with that OST cam.

I have a modified 93 octane start up tune from OST I will be starting up and doing breaking in on. So far there are no differences in anything to do with cam timing, VVT, etc that I can see at least. I was anxious to see the changes myself, Has me a bit concerned but I have to trust my tuner, not their first rodeo in this I have to bank on. I’m assuming after reviewing run logs Rev2 will start adding such and timing back and then back over to corn.

 

[16GoManGoHC2]

Ok, vacations over, back to business, and unfortunately back to work tomorrow
Today I got the pistons cleaned and inspected and assembled onto the rods. Rings and bearings installed, ready to go into the holes.

 

[16GoManGoHC2]

Bores coated in Total Seal Quick Seat, will also lube rings with Total Seal’s piston assembly lube, rings should seat quick and tight. The Quick Seat turns the bores green if they are totally clean, it’s ready for pistons.

 

[drag racer]

great job! The hardware is too dang purrty to be hidden in the block ;-)

 

[16GoManGoHC2]

Houston we have a short block!!

Time for bed, 445 am comes around waaayyy to quick

 

[16GoManGoHC2]

So here’s last nights doings. Recheck each and every piston to be sure rings are right side up and gaps in proper places, locks in place, rod orientation correct, install in Total Seal ring compressor set to 4.090” ID. BTW I HIGHLY recommend this ring compressor, worked EXCELLENT!!
Install 2 piston assemblies, lube bearings snd journals with Driven Assembly Gel, measure and record length of each rod bolt, put cap in place, Tq to 40 ft lbs then 90, measure stretch on each rod bolt to insure its between the .005-.006” stretch wanted by Manley. Verify stretch gauge I made from a desk lamp clamp after every rod to calibration standard I made.
Check clearance between each rod set main journals, ensure oil squirters are not hitting pistons. Measure crank end play before and after all pistons are installed, measure piston rock BDC, measure Piston deck height clearance. All passed. Next step change springs, retainers, and locks in the heads to a higher RPM capable Comp Cams .630” lift kit.

 

[vortecd]

You need to build another one using a clear block and put it under a glass coffee table so you can admire it everyday

 

[16GoManGoHC2]

You need to build another one using a clear block and put it under a glass coffee table so you can admire it everyday

One has been enough lol. Admiring its performance after its installed, running, and tune completed and making 1000+ wheel will be enough for me lol
I just want to get back to driving it, this has taken waaaayyyyy longer then first planned for.