Just catching up. What a rollercoaster. Sad (old turbos), then happy (new turbos), then sad again (motor). Sorry.
How many miles on the engine?
How many miles on the engine?
Rising from the ashes - Valhalla
- Thread starter Valhalla
- Start date
And that statement right there is the $64 question. I do monitor EGT's but only on #1 , not all of them. I'll try and do a pressure test later in the week and see if I hear the pressure loss coming from the crankcase. If I do, I may be in the same boat as Motormouth94. Have already talked with Chris at Science of Speed. Was NOT planning on this. Looks like a full tear down and go from there. But at least there are options. All more expensive than I want to spend, but I have options.
JC I’m sorry to hear that brother, been there twice myself so I know that feeling all too well.
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Hey Dave, welcome back. 120k on the motor. And I did major service on this just a couple of years ago. If it wasn't for bad luck, I wouldn't have any. But it's OK. I'll fix it. I'll PM you later.
Thanks, I'll get her fixed. Hopefully will start the tear down and inspection next month.
So got the exhaust bungs installed and injectors back. The injectors needed help as they were off by up to 8% at idle. Little less as we climbed to 50 and 100 percent but now they are identical and 100%. Put the car back together and now a new problem. Looks like I have a wideband sensor starting to fail. I'll replace it tomorrow.
Have ordered up the special tapper wrench and adjuster so will adjust valves after they arrive and then check compression again. What else do I have time for?
March 23 - went down to Science of Speed and got a couple of new UEGO widebands and replaced them both. Car is up and running as well as it can. Next up a pressure test and valve adjustment.
Have ordered up the special tapper wrench and adjuster so will adjust valves after they arrive and then check compression again. What else do I have time for?
March 23 - went down to Science of Speed and got a couple of new UEGO widebands and replaced them both. Car is up and running as well as it can. Next up a pressure test and valve adjustment.
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The special tools arrived so I figured I'd start with the pressure test. I only tested cylinder 6 as that was holding the least amount of compression. Pumped the cylinder up to 150 psi and with my wife's stethoscope, I listened intently at the crankcase, intake and exhaust. I heard nothing at the crankcase but did hear movement at both intake and exhaust. I then asked Pam to lend her well trained ear to all three locations without sharing with her what I heard. She is a NICU nurse with 30 years experience and has the best of hearing. She listened to all three locations several times and told me "I hear nothing from the crankcase but I hear a little from the intake and definite movement in the exhaust". I did a little happy dance right on the spot!
So without having to contemplating a full tear down and rebuild, I will adjust all the valves and then check compression on all cylinders again to see if I can even out all the cylinders. I know it will be a PITA, especially on the rear bank, but I am anxious to see just how far off the lash is, especially on #6 . I've never been so happy to put in 4+ hours of work on this car. I'll post up results when finished.
Update: So what did I find? I did a leak down test of the front bank before adjusting the valves. Placed the gauges on number four and proceeded. Found it holding barely 70% and numbers five and six were a lot worse. I did adjust 11 out of the 12 valves on the front bank (one was in spec) and then checked compression again. No change at all. So it looks like I'm in for a tear down and see what we need to do. Will plan for this summer when life gets back to some normalcy, we all hope.
So without having to contemplating a full tear down and rebuild, I will adjust all the valves and then check compression on all cylinders again to see if I can even out all the cylinders. I know it will be a PITA, especially on the rear bank, but I am anxious to see just how far off the lash is, especially on #6 . I've never been so happy to put in 4+ hours of work on this car. I'll post up results when finished.
Update: So what did I find? I did a leak down test of the front bank before adjusting the valves. Placed the gauges on number four and proceeded. Found it holding barely 70% and numbers five and six were a lot worse. I did adjust 11 out of the 12 valves on the front bank (one was in spec) and then checked compression again. No change at all. So it looks like I'm in for a tear down and see what we need to do. Will plan for this summer when life gets back to some normalcy, we all hope.
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Sorry to hear JC.
What is the cost difference between going with stronger rods and pistons vs only pistons and keep stock rods?
Are you think about sleeving the block as well?
What is the cost difference between going with stronger rods and pistons vs only pistons and keep stock rods?
Are you think about sleeving the block as well?
Bottom End options
I am weighing those options now. I could;
1) Say screw it and just buy an SOS Stage 2 Motor and transfer my parts on to the short block. But that option is probably $10-12k. The good side is it would mean near zero down time, the bad, it's $12k. But the motor would stand up to 600 rwhp and the rest of my system is capable of handling that power.
2) There is a local machine shop that has NSX blocks in stock, some sleeved and some just prepped. Price isn't horrible but now I would have to blueprint it and order up pistons and possibly rods. I can source bearings but this is a lot more machine work than I want to do, especially after reading the MotorMouth94's trials. Price tag all in and done would be around $9k and it would take some time. Power potential is +700 but that is way more than I need/want.
3) This is what I will probably do but only after the motor is disassembled and inspected for damage. I need to see what I have and why it did what it did, and then fix that before I do anything else. Send the heads out for inspection, valve grind and replacement of any damaged valves. Port and polish. Looking at possibly upgrading springs and using titanium retainers. Had the guides replaced a couple of years ago but will have them inspected/replaced as necessary. Inspect the pistons and rings, but will probably end up boring out the block a touch and installing 2618 forged pistons at normal compression. I'll have SOS rebush the OEM titanium connecting rods and by using them, I can retain my existing main bearings (provided they are still within spec). Also while it's apart I'll have the IM ported and polished. I'm probably looking at ~ $4k although I'll budget for more. This would be the time to add a billet oil gear and some other engine safety devices. This will still give me a build competent of +500 rwhp and I am just fine with that. Will take some time over the summer but it's too hot to drive then and our race season is off at that time of year. Just want to be ready for NSXPO. But will see the direction after I crack her open. No rush at this point, she still runs.
I am weighing those options now. I could;
1) Say screw it and just buy an SOS Stage 2 Motor and transfer my parts on to the short block. But that option is probably $10-12k. The good side is it would mean near zero down time, the bad, it's $12k. But the motor would stand up to 600 rwhp and the rest of my system is capable of handling that power.
2) There is a local machine shop that has NSX blocks in stock, some sleeved and some just prepped. Price isn't horrible but now I would have to blueprint it and order up pistons and possibly rods. I can source bearings but this is a lot more machine work than I want to do, especially after reading the MotorMouth94's trials. Price tag all in and done would be around $9k and it would take some time. Power potential is +700 but that is way more than I need/want.
3) This is what I will probably do but only after the motor is disassembled and inspected for damage. I need to see what I have and why it did what it did, and then fix that before I do anything else. Send the heads out for inspection, valve grind and replacement of any damaged valves. Port and polish. Looking at possibly upgrading springs and using titanium retainers. Had the guides replaced a couple of years ago but will have them inspected/replaced as necessary. Inspect the pistons and rings, but will probably end up boring out the block a touch and installing 2618 forged pistons at normal compression. I'll have SOS rebush the OEM titanium connecting rods and by using them, I can retain my existing main bearings (provided they are still within spec). Also while it's apart I'll have the IM ported and polished. I'm probably looking at ~ $4k although I'll budget for more. This would be the time to add a billet oil gear and some other engine safety devices. This will still give me a build competent of +500 rwhp and I am just fine with that. Will take some time over the summer but it's too hot to drive then and our race season is off at that time of year. Just want to be ready for NSXPO. But will see the direction after I crack her open. No rush at this point, she still runs.
Good luck!
Thank you.
That is my first option too. Have a very good shop here in Phoenix and will be talking to them this morning. The parts list is built and priced so just need to know shop prices and time lines.
Am I correct in thinking that rebuilding a motor piecemeal and adding FI is less reliable then adding FI to a original long block....
The weak point in an NSX motor is the pistons, once you go FI. The ringlands in particular. Once pistons are upgraded to forged 2618 (used specifically for FI) the next weak point is the crank at around 700 hp. I'm not even talking about the transmission. The five speed is stronger than the six.
That may be the case but if I find issues with them at 400, why would I try to use them again for 500? I'll pay for the upgraded forged pistons and then not have to worry about it.
True, most people just upgraded to forged pistons for peace of mind or more room for later. Cracked ring land is not because of the pistons can’t handle the power. But if u looking for north of 400whp then replace the pistons for sure. Motor build will become a money pit very fast. I rather fix it fast and enjoy the car than have it on the lift for couple years. Gl with ur build
I just want to say that I read this thread up until this point in time in one go and it was a proper soap opera for any car enthusiast. It went from tragedy to romance to action before coming back to tragedy, but it sounds like things are well in hand to take things to the next level. I really appreciate the build and the car...beautiful work all around!
My ownership of NSX's has read like a proper Greek tragedy, I will admit. So why do I continue this play? The car, the people, the look others give you when out on the road/track. I simply can not walk away. It OWNS me.
JC if you are thinking of running the stock rods with aftermarket forged pistons, check with the machine shop about having them bushed to accept the pistons. Apparently that can be an issue and they were charging an extra grand for that when I inquired. I removed my Pauter rods and installed a matched set of OE rods on my second rebuild so that’s when I found out.
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Yikes, an extra grand for an engine safety issue.. “sure we can help ensure your don’t blow your ish... we recommend it actually... but uhhh...it’s going to cost ya”
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You are correct sir. Thankfully I have SOS in my backyard so when I get my new pistons from them, I'll hand them my stock rods to be bushed. Yes it will cost a bit but the alternative is even more expensive. Both in dollars and time wise. Fortunately the body work is coming along nicely. Pictures to follow.
Yes sir, pay once, cry once.
So what have I been doing lately? Well we still have no room set aside at the shop for me to begin the engine removal/tear down/build, I thought I might freshen up the exterior. The vinyl wrap has lasted five years and done quite well. But some parts had taken some hits due to canyon runs and tracking. So I figured I'd re-wrap the front bumper and side sills. Well, it didn't go quite as planned.
I ordered the same wrap and color as before but once the new wrap was applied, the old wrap looked dull, transparent and not even close in color. Avery must have changed the formula (for the better). So I decided to re-wrap the entire car again. Taking the old wrap off is no big deal. If you go very slowly. If you go fast, chances are you will leave behind the adhesive which is a bear to remove. But the original job did its purpose. It looked great, changed the color of the car and protected the OEM paint incredible well.
I had new body panels which I installed. i replaced my original fenders with Downforce GT fenders which are 8MM wider This was to accommodate wider front sneakers. I also ordered a Downforce GT rear diffuser. Last piece was a Shine GT lower front bumper. The car is a street car/daily driver/track menace so I needed to balance a lot of things. I needed more rubber under the car, more down force, and for it to look better. I think I'm getting closer.
The new front bumper is a far superior look to anything else I've seen. I'm working on a full splitter and undertray which will protect and enhance it's function. The lower bumper really looks like it should have come with the car OEM. I need to re-work my exhaust to fit up above the rear diffuser but that is in the works. The rest of the car is going to be finished wrapping this weekend. Looking forward to getting her back on the road. Not able to up load photos at the moment due to......IHNFI!
I ordered the same wrap and color as before but once the new wrap was applied, the old wrap looked dull, transparent and not even close in color. Avery must have changed the formula (for the better). So I decided to re-wrap the entire car again. Taking the old wrap off is no big deal. If you go very slowly. If you go fast, chances are you will leave behind the adhesive which is a bear to remove. But the original job did its purpose. It looked great, changed the color of the car and protected the OEM paint incredible well.
I had new body panels which I installed. i replaced my original fenders with Downforce GT fenders which are 8MM wider This was to accommodate wider front sneakers. I also ordered a Downforce GT rear diffuser. Last piece was a Shine GT lower front bumper. The car is a street car/daily driver/track menace so I needed to balance a lot of things. I needed more rubber under the car, more down force, and for it to look better. I think I'm getting closer.
The new front bumper is a far superior look to anything else I've seen. I'm working on a full splitter and undertray which will protect and enhance it's function. The lower bumper really looks like it should have come with the car OEM. I need to re-work my exhaust to fit up above the rear diffuser but that is in the works. The rest of the car is going to be finished wrapping this weekend. Looking forward to getting her back on the road. Not able to up load photos at the moment due to......IHNFI!
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