Blew up my V8, Starting Over

[scribb]

For years almost any question I had about my 05 Sport, I could find answers here with a search, and somebody--usually 10 or 20 people--had already been there done that and came back with pictures and schematics. You guys are awesome. Thank you for being able to change my dash lights and find the right steel brake lines.

Now I've got a bigger problem. A couple of weeks ago, I got forced off the freeway while avoiding an accident during a big storm, and plowed into deep water at about 50 mph. The engine hydrolocked. I found pieces of one of the rods in the oil pan.

The correct engines I can find from places like LKQ are at around 120k miles, and are still running $2-3k, plus another two grand in parts and certified mechanic labor necessary to get a warranty. Seems like a lot for an engine with an unknown history.

I've looked at remanufactured engines, and after reading several pages of BBB complaints against nearly every company in that game, I've decided to bite the bullet and rebuild the engine from the ground up. Especially as I plan to keep my V8 Sport forever. It's a beast.

So I'm looking for ideas and recommendations on several of the key decisions on a rebuild: Compression, stroke, rods and pistons, cam, ecu, exhaust, peripherals.

I know there are endless areas of debate, so I'll frame my own decision with this objective:

I want to get the most power I can get from an NA engine (yeah, I know, but no, I'm not supercharging it), and still get 150k miles out of it. The question is, how much power can I get, and with what setup, with a budget of around $7k?


Main Build Questions

I get the impression that there's not a ton of room to bore 2uz cases, but there is a lot of room to stroke. Is that correct?

Assuming forged rods and pistons, can anyone point me in the right direction for figuring out the sweet spot of crank (if not stock), heads and cams to get a good balance of power and reliability?

I'll be putting on Thorley headers and new catback exhaust. I assumed dual all the way back, but the shop is saying that keeping the y-pipe won't have a big impact on power, other than sound. Any recommendations on exhaust?


I'm sure I'm just scratching the surface, but I appreciate any input on the build. I'm pulling the motor this weekend and shipping it off. Hoping to get my homework done to make some decisions.

BTW: I cross posted at Lextreme after reading through a lot of build threads there. If I get some good feedback, I'll post it back here. Thanks!

 

[scribb]

That's what I found in the oil pan.

 

[TenTwelve]

I have nothing to add, but this thread intrigues me. Subscribed.

 

[Honkey Cat]

Interested as well, how many miles were on your v8?

 

[rdruss]

Rebuild of 4.7 v8

it will be interesting to see what you come up with, not sure there's a lot of 'hot rod' parts available though. Forged rods a definite, bump the compression half a point, can do that by milling the heads, get a mild port job and if any cams available that not too wild in conjunction with your headers should give you a nice boost.
keep us posted!

 

[scribb]

it will be interesting to see what you come up with, not sure there's a lot of 'hot rod' parts available though. Forged rods a definite, bump the compression half a point, can do that by milling the heads, get a mild port job and if any cams available that not too wild in conjunction with your headers should give you a nice boost.
keep us posted!

That's actually pretty close to what I've arrived at.

The fun part was pulling the motor in the rain. Seems like every weekend it's been raining, so I finally scheduled to pull it rain or shine. Of course we got the Polar Vortex Atmospheric River. 40 degrees and pouring rain. I pulled the motor under a tarp. Good fun.

Stripped the engine down and brought it up to Yota1 Performance in Modesto. They specialize in machining and building Toyota performance engines. Looks like they do more 22Rs, but the owner, Nick, said he's seeing more 2uzs.

Got a quick tour of the machine shop.

And then we talked about the build. The plan so far--assuming the block is okay--and pending a little research by the shop:

forged rods
forged pistons
upgraded cams
milled heads to increase compression to 10.2-1
port heads

I'll get the details on the parts and machining as everything comes together. Combined with headers and ecu tune, that's about the best balance I can find between performance and longevity.

I'm also taking the opportunity to refresh the whole motor assembly--replacing most vacuum and water hoses, cracked electrical connectors--and replacing lca bushings.

One thing I need to research is how to clean the air intake assembly. The machinist treated it delicately but said it needed to be cleaned. There's a lot of plastic so I'm assuming solvents are a bad idea.

One thing I'll say about the project. It's looks pretty hairy when you start pulling it all apart. I'm used to wrenching on a 65 Mustang, which has pretty much nothing but iron under the hood. The 4Runner looks like a bowl of spaghetti. But once you start pulling the systems apart, it all starts to make sense. You just have to be meticulous about tagging and bagging nuts and bolts.

To whomever asked: the motor had 145k miles on it. The pistons were the weak link when I hit deep water. Apparently powder metal rods have great longevity, unless they hit something hard. Water in a cylinder under compression is really hard.

 

[scribb]

Quick follow up note on some rebuild additions/precautions.

1. Machinist strongly recommended replacing the starter with an OEM unit. I never realized this before taking the motor out, but the starter motor is *under* the air intake, along with the smog air pump unit. Significant pain to replace, and with 150k miles on it, not a bad call to replace it.

2. Similarly, I'm going to likely replace the secondary air smog pump for the same reason, but with the GM unit that is comparable/cheaper. Last thing I need is to have the infamous smog pump problem with a fresh motor, and with my luck that will happen right after I start up the new motor.

3. Will also replace the radiator. Spending several thousand on a brand new build and not replacing the hundred dollar radiator doesn't make a lot of sense.

Am I missing anything obvious in that category?

 

[MountainFunRunner]

Sorry to hear about your 4runner that's really rough. I don't have that level of mechanical skill but was eventually thinking about an engine swap. My v8 is rated at 260hp and 306lb ft. I can do the typical air intake, thorley headers and exhaust to liven it up and if I really want get the URD supercharger but its 6k+. Ive been looking at NA engines but haven't a clue which will fit. The 4 7 is 286cu inches...would the bay hold a 350? Best of luck on the rebuild

 

[scribb]

Sorry to hear about your 4runner that's really rough. I don't have that level of mechanical skill but was eventually thinking about an engine swap. My v8 is rated at 260hp and 306lb ft. I can do the typical air intake, thorley headers and exhaust to liven it up and if I really want get the URD supercharger but its 6k+. Ive been looking at NA engines but haven't a clue which will fit. The 4 7 is 286cu inches...would the bay hold a 350? �� Best of luck on the rebuild

Turns out you can get a lot of horses out of these engines without forced air. Based on where I am in the process now, it looks like I'll be able to get between 350 and 400 naturally aspirated, which is better than I expected. Here's the quick update.

First off, it turned out I blew the block. There was no external damage, but the rod punched a hole in the oil gallery, so I got a donor block from a Sequoia. Forged rods were pretty easy to come by. Forged pistons had to be custom made, but not difficult. I decided not to increase the compression in case at some point in the future I want to add boost.

Luckily the heads were good, so those are getting surfaced and ported. The biggest challenge at the moment is finding proven cams, particularly since it's VVTi. I haven't gotten any response from Crower, which is disappointing. One of the moderators at Lextreme pointed me to Kelford Cams in New Zealand, and it turns out they're about to put a whole bunch of new UZ cams on the market in a few weeks, barring any delays. They were really responsive by email, and gave me a list of cams ranging from OEM to 750hp racing motor cams. I'm looking at a road cam and high performance springs that, with ECU, they're projecting will get me to 360hp.

I'm now also starting the search for the right ECU. I'm talking with one of the pros on Lextreme, who's recommending a dedicated ECU, not a piggyback, in order to properly control timing and fuel. But I don't need to just find a unit, I need a tuner, and so far, even the Bay Area, finding a tuner that does 2UZs is turning out to be a real challenge.

BTW. I'm planning to smog this truck in California. (No, really.) It's possible, though not fun or legal, to swap out headers. But I can't really swap out cams, so getting the right tune for the cams is going to be a challenge.

So, the block should be in assembly next week. Then I'll be stalled until the cams come in, unless Crower decides to return a call and has a comparable set of cams I can get before Kelford ships in (cough) 5-6 weeks. That gives me time to finish cleaning parts, and, while I have the motor out, replacing LCA bushings, getting the transmission fully serviced, and getting everything else together.

For exhaust, I'm planning on going with the URD MK3. It's more expensive than the Gibson, but I'm putting this much work into the engine, it seems like a good investment. (I also feel like the pitch of the Gibson is too sharp for a V8, but that's just personal preference.)

What I'm learning about the 2UZ VVTi is that there is a ton of potential in these engines, even without forced induction. I think there's so much talk about superchargers, because it's relatively easy to slap on a system and get 100 ponies without tearing down the motor. These engines have had such phenomenal reliability, that not a ton of people have had much reason to tear them down and rebuild them. When they did blow, you could get a junk yard motor with reasonable miles for pretty cheap compared to a rebuild, so again, not many people have done it. But now that junked V8s have higher miles, I'm guessing more people will start rebuilding, and that should improve the market for proven pistons, cams, ecus, etc.

It seems like Toyota was really conservative in how they set these up, maybe in part to protect those powdered metal rods. Put in forged internals and a good set of cams, along with ecu, intake and exhaust, and you can get a lot of power out of these motors before you add any boost.

BTW: I may be wrong (I'm not a pro mechanic, so take anything I say with a grain of salt) but in my research, there are cheaper supercharging options that will work with the 2uz. Check out the Eaton m90, which has been used a lot on 1uz motors (Lexus SC400).

 

[MountainFunRunner]

Turns out you can get a lot of horses out of these engines without forced air. Based on where I am in the process now, it looks like I'll be able to get between 350 and 400 naturally aspirated, which is better than I expected. Here's the quick update.

First off, it turned out I blew the block. There was no external damage, but the rod punched a hole in the oil gallery, so I got a donor block from a Sequoia. Forged rods were pretty easy to come by. Forged pistons had to be custom made, but not difficult. I decided not to increase the compression in case at some point in the future I want to add boost.

Luckily the heads were good, so those are getting surfaced and ported. The biggest challenge at the moment is finding proven cams, particularly since it's VVTi. I haven't gotten any response from Crower, which is disappointing. One of the moderators at Lextreme pointed me to Kelford Cams in New Zealand, and it turns out they're about to put a whole bunch of new UZ cams on the market in a few weeks, barring any delays. They were really responsive by email, and gave me a list of cams ranging from OEM to 750hp racing motor cams. I'm looking at a road cam and high performance springs that, with ECU, they're projecting will get me to 360hp.

I'm now also starting the search for the right ECU. I'm talking with one of the pros on Lextreme, who's recommending a dedicated ECU, not a piggyback, in order to properly control timing and fuel. But I don't need to just find a unit, I need a tuner, and so far, even the Bay Area, finding a tuner that does 2UZs is turning out to be a real challenge.

BTW. I'm planning to smog this truck in California. (No, really.) It's possible, though not fun or legal, to swap out headers. But I can't really swap out cams, so getting the right tune for the cams is going to be a challenge.

So, the block should be in assembly next week. Then I'll be stalled until the cams come in, unless Crower decides to return a call and has a comparable set of cams I can get before Kelford ships in (cough) 5-6 weeks. That gives me time to finish cleaning parts, and, while I have the motor out, replacing LCA bushings, getting the transmission fully serviced, and getting everything else together.

For exhaust, I'm planning on going with the URD MK3. It's more expensive than the Gibson, but I'm putting this much work into the engine, it seems like a good investment. (I also feel like the pitch of the Gibson is too sharp for a V8, but that's just personal preference.)

What I'm learning about the 2UZ VVTi is that there is a ton of potential in these engines, even without forced induction. I think there's so much talk about superchargers, because it's relatively easy to slap on a system and get 100 ponies without tearing down the motor. These engines have had such phenomenal reliability, that not a ton of people have had much reason to tear them down and rebuild them. When they did blow, you could get a junk yard motor with reasonable miles for pretty cheap compared to a rebuild, so again, not many people have done it. But now that junked V8s have higher miles, I'm guessing more people will start rebuilding, and that should improve the market for proven pistons, cams, ecus, etc.

It seems like Toyota was really conservative in how they set these up, maybe in part to protect those powdered metal rods. Put in forged internals and a good set of cams, along with ecu, intake and exhaust, and you can get a lot of power out of these motors before you add any boost.

BTW: I may be wrong (I'm not a pro mechanic, so take anything I say with a grain of salt) but in my research, there are cheaper supercharging options that will work with the 2uz. Check out the Eaton m90, which has been used a lot on 1uz motors (Lexus SC400).

Interesting is there a reason you went with the sequoia over the 2010 lexus gx460? I think they have the 4.6 or so but its rated at 301hp and I think it'd be about as reliable. Where would you start with a normal 4.7 v8? I'll look at the urd exhaust, I agree the Gibson is a bit tinee. Is that 350/400hp rebuilding the engine or adding bolt ons. I plan on adding armor via front and rear bumpers and some offroad items on the roof rack and want to add performance accordingly. I have a fair amount of mechanical skill but taking apart a functioning engine scares me. Sounds like your pretty good mechanically to me

 

[MSRP.]

If and when you find the tuner and standalone, after that much effort, you might as well tinker around with meth injection for more power/safety margin.

Hope you don't put all this effort into research and just land back at a stock rebuild!

 

[scribb]

If and when you find the tuner and standalone, after that much effort, you might as well tinker around with meth injection for more power/safety margin.

Hope you don't put all this effort into research and just land back at a stock rebuild!

Ha. You're too close to the truth for comfort. I'm holding out, though. The current downside is I may need to go with a Link Storm ECU to run this thing, and at $1200, not including the cost of tuning (by an as-yet unidentified tuner), I'm starting to gnaw my fingernails.

 

[MSRP.]

Ha. You're too close to the truth for comfort. I'm holding out, though. The current downside is I may need to go with a Link Storm ECU to run this thing, and at $1200, not including the cost of tuning (by an as-yet unidentified tuner), I'm starting to gnaw my fingernails.

Yep, if you do intend on “keeping it forever” like you stated in your OP, I’d keep the stock internals.
If you need more pep, the DT headers look good.
If you wanted more “audible” rumble, I can, in good faith, recommend just cutting a few holds after the cats prior to entering the muffler.
My old exhaust was basically completely disconnected at that union before the muffler, and on startup and taking off from a stop, the v8 grumble was fierce. BUT on the highway, it was just as quiet as stock.
Still cursing the government to this day.. needed to fix the leak for emissions testing, but a year later, they’re scraping the program up here.
FML
Or do what I do, drive a slower 4R to make you really appreciate the v8 (mine’s only the lowly 2003 v8 too without vvti)

 

[Formidable]

Very interested to see the outcome. I will end up going built engine URD supercharger at some point.

You will be happy with the URD MK3 exhaust and Y pipe. Outstanding system from a quality and sound standpoint. Very happy with mine.

 

[scribb]

Quick update:

Committed to the Kelford cams. Had a very disappointing call with WebCams--they sounded dismissive when I said I wanted cams for a 2uz, saying "well, they start at $2700", sounding like they just assumed that would get me off the phone. It did, but less about the price than the stand-off-ishness.

Found a tuner, which was a lot harder than I anticipated. Finally found him by looking up dealers for some of the standalone ECUs. He's never done a truck, but he's a Toyota specialist, and has done a lot of SC400s (1uz) and proved in just a few minutes of discussion that he really knows his stuff and is really excited about working with a machinist on a 4Runner motor. I'm not going to out him until we get down the road.

After some discussion back and forth, I think I'm convinced to go with increasing compression to 10.1:1. This will pretty much cut off the option to do much with boost, but the amount of grunt we'll get out of the motor is what I really want. It's going to mean more machining--smoothing out all the rough edges of the internals to maximize flow, and porting the heads properly. The good news is, with the Kelford shipping delay, we'll have more time to get the machining right.

Starting to worry a little bit about the next weakest link with the added horsepower. The tranny is getting worked, but I haven't done anything yet with the transfer case, shafts, diffs, etc. May just steel myself for some trial by fire close to home.

 

[Inv4drZm]

Sweet thread, can't wait to blow my engine too LOL.

Here is another similar thread with some dyno numbers you can use as a reference.

Stage 1 Transformation (Exhaust, Chip, Intake) - Toyota 4Runner Forum - Largest 4Runner Forum

It'll be interesting to see the dyno numbers once its all said and done. Few people have supercharged this motor and even fewer (if any) have tore it apart for NA mods from what I've seen. URD claims +100hp and +100tq at 5.5psi of boost, hard to beat that.

 

[scribb]

Sweet thread, can't wait to blow my engine too LOL.

Here is another similar thread with some dyno numbers you can use as a reference.

Stage 1 Transformation (Exhaust, Chip, Intake) - Toyota 4Runner Forum - Largest 4Runner Forum

It'll be interesting to see the dyno numbers once its all said and done. Few people have supercharged this motor and even fewer (if any) have tore it apart for NA mods from what I've seen. URD claims +100hp and +100tq at 5.5psi of boost, hard to beat that.

Good benchmark. Thanks. Tuner and builder are saying we should be around 400, but we'll see. That would be a gain of 130hp at the crank, for ~roughly~ similar cost for URD supercharger when all is said and done. My gamble is it will be a stronger motor. Oh, and I didn't have much of a choice for supercharging with a blown engine. Just hoping the cams ship on time.

 

[scribb]

If and when you find the tuner and standalone, after that much effort, you might as well tinker around with meth injection for more power/safety margin.

Hope you don't put all this effort into research and just land back at a stock rebuild!

I'm starting to look into meth injection now that I've got most of the build issues sorted out. Got word today that the cams and springs are going to ship on time. Got my tuner connected with my builder, and they're stoked to see this project come together. Got a plan for parallel wiring a standalone ECU. So, now I'm starting to figure out all the peripherals, and methanol is top of the list--particularly as I decided to go forward with 10.1:1 compression.

For anyone not familiar with meth injection, I'll give you my rudimentary understanding of it. Methanol is mixed with water and injected into the air intake. The mixture cools the air and lowers air intake temperature, which lowers the risk of detonation during combustion, particularly when you advance timing. Since I'm adding street cams, increasing compression and advancing timing with an ECU, the chances of detonation are increased. Methanol will both increase the safety of pushing performance, and have the added benefit of allowing me to use normal gas, since the methanol also increases the octane in the air fuel mixture. Oh, and it can get me anywhere from 15 to 40 added hp, depending on how the motor is tuned.

My original goal was to build a reliable motor and get around 350hp naturally aspirated. It's looking like 400hp is definitely in range, more if I really want to push the envelope, which I'm probably not. Wherever the capacity of the motor winds up after we get it fully built, I'll dial it back to a max of 80%, and dial it back further for daily use. We'll see where that lands.

One of the items further down my list to research is either an android or PC ECU interface I can display on the stereo screen, to show gauges and change ecu settings. I've seen a few things in that realm, just need to zero in on a solution that will work.

 

[gamefreakgc]

Quick update:

Committed to the Kelford cams. Had a very disappointing call with WebCams--they sounded dismissive when I said I wanted cams for a 2uz, saying "well, they start at $2700", sounding like they just assumed that would get me off the phone. It did, but less about the price than the stand-off-ishness.

Found a tuner, which was a lot harder than I anticipated. Finally found him by looking up dealers for some of the standalone ECUs. He's never done a truck, but he's a Toyota specialist, and has done a lot of SC400s (1uz) and proved in just a few minutes of discussion that he really knows his stuff and is really excited about working with a machinist on a 4Runner motor. I'm not going to out him until we get down the road.

After some discussion back and forth, I think I'm convinced to go with increasing compression to 10.1:1. This will pretty much cut off the option to do much with boost, but the amount of grunt we'll get out of the motor is what I really want. It's going to mean more machining--smoothing out all the rough edges of the internals to maximize flow, and porting the heads properly. The good news is, with the Kelford shipping delay, we'll have more time to get the machining right.

Starting to worry a little bit about the next weakest link with the added horsepower. The tranny is getting worked, but I haven't done anything yet with the transfer case, shafts, diffs, etc. May just steel myself for some trial by fire close to home.

The transmission will need a little help with heat, us 3rd Gen folks have that issue when pushing a lot of power through the stock transmission. Do 4th gens have an external transmission cooler though or is it just routed through the radiator? I'm on transmission #2 since the PO had to replace it due to the supercharger burning the fluid.

I commend your build though. I just found out about Yota1 recently but already did my engine swap. Budget didn't allow doing anything crazy though but I would have loved to increase the bore and put some real-deal pistons in. However, I do give a word of caution about the camshafts: the reason why I had to replace the engine was I installed camshafts with shim spacers. Avoid those like the plague. And yes, you figured it out already but if you add any sort of lift the springs do not hold up and will go out of adjustment really quick so stiffer springs are must for any aftermarket camshaft that increases lift.

For smog, just keep the cams conservative without too much overlap and you'll be ok. However, the stock ECU may not play nice with all that extra power, you'll probably be looking at upgrading the injectors (fine in closed loop but might run crazy lean in open loop with stock injectors), which means you'll need a way to drive them properly so a piggyback will be in order, then a way to read AFR's so you'll need a wideband... catch my drift? Toyota ECUs are an absolute pain to tune though.

When do you expect your engine to be back up and running?

 

[gamefreakgc]

I'm starting to look into meth injection now that I've got most of the build issues sorted out. Got word today that the cams and springs are going to ship on time. Got my tuner connected with my builder, and they're stoked to see this project come together. Got a plan for parallel wiring a standalone ECU. So, now I'm starting to figure out all the peripherals, and methanol is top of the list--particularly as I decided to go forward with 10.1:1 compression.

For anyone not familiar with meth injection, I'll give you my rudimentary understanding of it. Methanol is mixed with water and injected into the air intake. The mixture cools the air and lowers air intake temperature, which lowers the risk of detonation during combustion, particularly when you advance timing. Since I'm adding street cams, increasing compression and advancing timing with an ECU, the chances of detonation are increased. Methanol will both increase the safety of pushing performance, and have the added benefit of allowing me to use normal gas, since the methanol also increases the octane in the air fuel mixture. Oh, and it can get me anywhere from 15 to 40 added hp, depending on how the motor is tuned.

My original goal was to build a reliable motor and get around 350hp naturally aspirated. It's looking like 400hp is definitely in range, more if I really want to push the envelope, which I'm probably not. Wherever the capacity of the motor winds up after we get it fully built, I'll dial it back to a max of 80%, and dial it back further for daily use. We'll see where that lands.

One of the items further down my list to research is either an android or PC ECU interface I can display on the stereo screen, to show gauges and change ecu settings. I've seen a few things in that realm, just need to zero in on a solution that will work.

I missed this post!

I run water/meth. Although cooling the intake charge is a nice bonus, you won't see much a benefit being N/A like us boosted folks will, especially since I can't install an intercooler so my intake charge is hot hot hot. Meth in itself makes no power, let me put that out there. Where you do make power is the ability to advance timing due to detonation suppression. More timing = more power, roughly 1% for each degree of timing you can advance.

I have not heard of anyone successfully wiring it a full standalone along with the stock ECU still connected. Replacing the stock ECU with a standalone will not pass smog but if you keep the stock ECU in and try and jump it with a standalone the stock ECU is going to try and de-tune everything you do, and quite successfully I might add. Most tuners won't touch Toyotas with a stock ECU for that reason. That's why I run a piggyback ECU, the AEM F/IC 6, which does not have the ability to advance timing, which is why water/meth makes no power for me.

However, if your tuner does find a way to get the standalone to work in series with the stock ECU and not de-tune it I would be very interested in working with them as well.