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Took the car out for a ride for the last 2 days. Its a little monster. Running great. I just need to tweak my fueling a bit. Just to close to maxing the injectors right now. But its funny, since i got nice wide drs on the back and its sorta warm out I wanted to try them out. Well from a dead stop a 75hp shot will blow though them unless i had some glue..lol But Im ready to race this thing. With good weather, a good tune, and a killer 60 foot, even with the smaller 3.23 gears out back, im guessing a 11.40-11.50 as she sits. Thats at a 15.5psi command and a 75hp shot untill 8psi.
why is the back of the car so high , dang thing sits like mine , po installed a second set of spring isolators to cjack the back up , but they also did the same thing in the front
why is the back of the car so high , dang thing sits like mine , po installed a second set of spring isolators to cjack the back up , but they also did the same thing in the front
To be honest I'm not sure. It's always sat like that.... mabey I should look at my springs I guess. Never really gave it a thought..
Have you tried launching it with out the spray to see if the gear is helping it spool sooner than the old gear?
Actually I did try that yesterday. I think it would work but the problem is my converter does not flash high enough with all motor outta the hole. It was flashing 3100 without n20 yesterday. So the turbo still lags to take off. With n20 it flashes to 3800 basically sending it to instantly spool. Literly 1/2 second on the data log. So for now I'm going to stick with the n20 at the line but at the track only. I do notice a difference though driving with the 3.23. Helps on the highway and will keep my rpm down a bit at the finish line. I'm just not sure if n it's going to slow the car down..but should know soon.
Update
I got all the guages wired up.. n20 boost new trans temp.
The weather has been crappy here in ohio so no racing yet. Fingers crossed it's warm a week from Saturday and I can hit up my first race. As long as the car runs like it's suppose to I'm guessing 11.40s off the bat. It's a fast ride. I got the tune dialed in. Yesterday I drove it and wanted to make sure the trans temp guage worked so I drove it for like 10 min then went for a wot pull.
So as soon as the boost built I was like Damm this thing is fast. Well turns out it was over boosting to a constant 19psi!!!! Thankfully my tune is good. Afrs were amazingly 11.5-11.8 the whole time. But the injector DC was 95-100...lol. I took the gate apart and found the reference line to be pinched. So I fixed it and it's back to running about 15.5psi.
At least I know the motor can handle it but the injectors are only 48lbs\hr so at 15.5ish psi it's back to 80-85 DC. Which is what I like to see.
I am running a 75hp shot outta the hole so that is why I'm guessing 11.40s or a touch lower with a good track. The 11.59 was 50 hp shot on a hot humid day. No roll cage in my car so if it does run that fast I'll slow it back down to a 11.50 car for the rest of the year. Next fall roll cage is going to happen.
They do have a no et class at milan which you can run what ever you want with no restriction. It cost more and the et will be on the slip only. Not on timing boards. So I may do that once as well at the end of the year when I push the engine hard.
sounds like here its been raining almost everyday for the past 2.5 weeks , but unlike u i no longer have a racetrack to goto atleast not one that is close enough 600 mile round trip to go drag racing now , so ive been focusing on setting the car up to go lsr racing instead , ill be going in sept and then selling the car after
also building a turbocharged bike to take lsr racing , that ill keep after though i can justify keeping that to use 2-3 times a year , the car on the other hand i cant justify keeping to only race 1-3 times per year
1st pass 11.32@122mph of course not on vid..lol. 2nd pass.... this.... no good at all. Happen right out of the gate at idle so I shut it off before I though of gassing it. Pretty damm depressed right now. I guess that's what I get for pushing it so hard.
Number 4 cylinder. Not sure what gave first but I need to pull motor to see. No holes in block and also no coolent in oil. But it just started to make a racket so I shut it off immediatly. Then loosened pan enough to grab a few pieces....which are all piston bits.
Here it is. The rest of the piston stuff is in the pan still. I just took the head off to see how bad the block was. The heads are fine. But as you can see the block is gouged quite bad... looks like the next move is lx9 or lz9 time.
I wish i knew what happen here. The car was idling when this happen. Sounded like a food blender so i quickly shut if off. I didnt drop a valve either. It just looks like the piston literly detached itself from being cracked and just shredded it after the fact. Damn same. Well i guess about 450-475Hp based off trap speed and weight is about the limit here...the pass before hand didnt have any detonation or kr at least on the log and my kr is quite aggressive in terms of degree per mil second
Was this on the same side that you had the head gasket let go last time?
Lx9 would probably get you back up and running sooner, your turbo headers would bolt on and you could use the 3400 plenum until you get an adapter for the lx9 plenum.
Was this on the same side that you had the head gasket let go last time?
Lx9 would probably get you back up and running sooner, your turbo headers would bolt on and you could use the 3400 plenum until you get an adapter for the lx9 plenum.
Actually the head gasket was on the other side. Cylinder 1 and 3. This went out on cylinder 4.
I have.a lead on a 112000 mile lx9 running supposidly for $275. Not sure what I need to look at as its already pulled but that might be what I end up getting.
when you get around to it will you check to see if any of your rods are bent?
gm rated them at about 400 hp, and I had 2 or 3 bend on my iron head 3.4 that was making 370 whp and 464 tq at the tires. I am thinking it was the tq that bent them vs the hp as I never took it above 5500 rpm. I don't know if I still have the pic otherwise I would post it. they were very noticeably bent. pistons held though lol
oh yea, I don't know how far you are from Blufton Oh, but I looked on car-part and there is a 3900 with 42k miles for $500
car part I searched for 2009 impala engine code LGD from zip code 43612 which is toledo.
That yard has 3 of them for about the same price and similar mileage. pretty good deals I think. you can haggle on the price too I bet.
lx9 would get you back up and running quicker though. lz would require new exhaust setup and coolant fab. Thats prob more of a winter project but those are good deals based on mileage and price. if you have the extra cash get both and work on the swap over the winter.
Dang I hate to go off topic, but please post some pictures, dyno sheet, time slip, something with the 3.4. A new thread would be great, those are some awesome numbers out of an iron head setup and I would love to read more about it.
I passed along the info on that 3500 I was looking at in my thread to Mark, hopefully we see the new engine in there soon!
send ur injectors out to be flowed , i sispect that cyl had gone lean at some point and rattled the piston , or it just happened to rattle that cyl on occasion now and then
that can also happen from a broken or sized up wristpin
edit
come to think of it u upped the nitrous shot didnt you ?
willing to bet it was nitrous related
I was running a 50 hp shot. Not very aggressive I think. But it may have caused it. I upped the n20 last year to 75 for a good part of the year but since I finally made up some frame connectors and did some other suspention work I lowered the n20 assuming my 60 would go down from the upgrades which it did. 1.68 60 foot on a 50hp shot.
I'm searching as we speak for a low mile lx9. I think I may go that route as they are more prevalent and it requires less changes so I could be back on the track late this year as I still want to redue some of the piping while the engines out and just clean up wireing and things like that.
I may flow the injectors but I definitly know they are for sale as I'll be in the market for 60lbs ones. The 48lbs are not big enough anymore or what I've been trying to do so I might as well swap them out while I'm replacing the engine.
The rods were not bent at all. That was definitly something I checked as earlier that day I trapped 123mph in the 1\4 which is flying imo.
I'm still looking for a decent 3500 to buy. Also making a list of things I will need such as a cam exc...
At john. If you want those injectors, I'll hold them for ya but I gotta get rid of them in the next few weeks or so. Id like 120 bucks for them if you come and pick them up. Let me know wh we think ya think bud.
I'm quite excited about running a 3500. Hopefully it's a much better engine then the 3.1/3100
I'm planning on rebuilding a 3500 if I get one and tossing all new bearings in it. Cleaning up the cylinders new rings and possibly new pistons..
The rods were not bent at all. That was definitly something I checked as earlier that day I trapped 123mph in the 1\4 which is flying imo.
I'm still looking for a decent 3500 to buy. Also making a list of things I will need such as a cam exc...
At john. If you want those injectors, I'll hold them for ya but I gotta get rid of them in the next few weeks or so. Id like 120 bucks for them if you come and pick them up. Let me know wh we think ya think bud.
I'm quite excited about running a 3500. Hopefully it's a much better engine then the 3.1/3100
I'm planning on rebuilding a 3500 if I get one and tossing all new bearings in it. Cleaning up the cylinders new rings and possibly new pistons..
with that much work id honestly do a stock vortec 350 , or grab a set of the 200cc heads and run a second s366 , u would end up faster or just as fast without pushing it so hard
the downside is new turbo headers , and a second turbo , or sell the s366 and grab a box stock s475 for 490$
jy vortec motor should be around 200-250$ , hsr intake can be had at around 200$ and if u dont wanna build up and forward headers u can buy a set for roughly 300$
or go right to the 3900 , ive seen to many issues with rods in the 3500 , if anything at all id do 3.4 bottom end with 3500 heads over a full 3500 which also saves u some fab work since u wont have to fab a motor mount and deal with the starter
I would just drop a 3500 with 100k miles on it, change the valve springs and see how it works! Should be close to what you are getting out of the 3.1.
Mars never did anything with his 3500, changed the springs, cam and hit it with some boost and went 11.1 at 130mph.
Most of the ones I have seen blow up have been where the bottom end was apart and put back together... if you blow up a 3500 you can be back in business with another one for a few hundred bucks.
If you need a lx5 TB let me know, maybe we can work out a deal on your old injectors!
if you are going to get a decent 3500 just to tear it down and put all new bearings in it, and new pistons and rings, just get a stupid high mileage one for dirt cheap. OR buy a low mileage lx9 and just replace the oil pump, skip everything else, and call it a day. in the end the low mileage lx9 will be cheaper money wise, and time wise, than a rebuild or semi rebuild of a lx9.
you want to get back on the road quick so you can race it this summer right? low mileage lx9 or a low mile 3100 will be your best bet since thats what you already have however with a rwd block.
however if you insist on doing a full tear down of a low mileage lx9, just buy a low mileage lz9. you already have the cam you can swap into that.
fyi, I hate when people keep suggesting what I do, so you are prob hating this page of your thread. lol
if you are going to get a decent 3500 just to tear it down and put all new bearings in it, and new pistons and rings, just get a stupid high mileage one for dirt cheap. OR buy a low mileage lx9 and just replace the oil pump, skip everything else, and call it a day. in the end the low mileage lx9 will be cheaper money wise, and time wise, than a rebuild or semi rebuild of a lx9.
you want to get back on the road quick so you can race it this summer right? low mileage lx9 or a low mile 3100 will be your best bet since thats what you already have however with a rwd block.
however if you insist on doing a full tear down of a low mileage lx9, just buy a low mileage lz9. you already have the cam you can swap into that.
fyi, I hate when people keep suggesting what I do, so you are prob hating this page of your thread. lol
one thing is no matter what he gets he has to open up the top ring gaps , high mileage engine prolly wouldnt need it done , but may need other stuff so its still a tossup
if you are going to get a decent 3500 just to tear it down and put all new bearings in it, and new pistons and rings, just get a stupid high mileage one for dirt cheap. OR buy a low mileage lx9 and just replace the oil pump, skip everything else, and call it a day. in the end the low mileage lx9 will be cheaper money wise, and time wise, than a rebuild or semi rebuild of a lx9.
you want to get back on the road quick so you can race it this summer right? low mileage lx9 or a low mile 3100 will be your best bet since thats what you already have however with a rwd block.
however if you insist on doing a full tear down of a low mileage lx9, just buy a low mileage lz9. you already have the cam you can swap into that.
fyi, I hate when people keep suggesting what I do, so you are prob hating this page of your thread. lol
Why replace the oil pump (specifically)? The LX9 oil pump is a good pump and haven't found any reason to suspect it could be a weak point.
Also the 3100 block will take the same amount of work to swap into his car as the LX9 block.
I always replace the oil pumps when buying a used motor. the pump is the heart of the engine. if thats no good, then the rest of the engine dies. I have found that most used or junkyard 60 degree engines suffer from LOPS; low oil pressure syndrome.
Putting in a new pump, I take apart the new pump, inspect the gears, remove any burs on the gears, and shim the oil pressure spring bypass to get me a little more oil pressure. Every 60 degree I have done this too has had 60-70 psi cold and 35-45 hot at idle. I like that oil pressure better than the 25 at idle COLD, I have found in some used 60 degree engines.
Its cheap insurance and gives me a chance to clean out the pan, and inspect the bottom end for anything obviously loose. I have had good results, and in doing this I have lost zero rod or crank bearings even with nearly 2.5 times the factory hp output.
Well guys i appreciate all the tips and such. Im definitly going the 3500 route. I dont plan to have it all together till probly this fall at the earliest but i really would like to make a few passes at the track if possible this fall with it.
The reason ill be slower to toss it all together is because i want to up my intake charge piping to all 3 inch. This is because the intercooler is 3 inch. the turbo outlet is 3 inch and the throttle body is 3 inch so i want to redue that. And route it a bit different as well. I want to re work the exhaust piping a tad bit as well. Also clean up my wiring disaster that i have from all the n20 sensors and everything else on the ride. And i want to build the engine to last though some abuse.
This set up will be built to fly. I promise you that.
This winter Ill be adding a trans brake and a 6 pt cage and a 9 inch rear. So I want 10 seconds out of this set up no matter what. If i could get mid 11s all day out of the 3.1L, I will be very dissapointed to not get 10s outta a 3500 and considering it will have a t brake.
So here is my list of stuff that i know i will need.
Dependent on the engine, bearings all the way arround
Moly rings
Forged pistons(if i can find them at a resonable price)
new locks and retainers(i plan to reuse my behive comp cam springs)
Cam(can I reuse my 270 split cam i have now if its in fine shape still?)
Throttle body adapter(3500 is drive by wire) im using my 7730 again.
Needless to say im pisssed that i blew it up but also happy because i knew that one day i would toss a lx9 or even a lz9 in this car. SO now is the time to build it up and do it right.
Well guys i appreciate all the tips and such. Im definitly going the 3500 route. I dont plan to have it all together till probly this fall at the earliest but i really would like to make a few passes at the track if possible this fall with it.
The reason ill be slower to toss it all together is because i want to up my intake charge piping to all 3 inch. This is because the intercooler is 3 inch. the turbo outlet is 3 inch and the throttle body is 3 inch so i want to redue that. And route it a bit different as well. I want to re work the exhaust piping a tad bit as well. Also clean up my wiring disaster that i have from all the n20 sensors and everything else on the ride. And i want to build the engine to last though some abuse.
This set up will be built to fly. I promise you that.
This winter Ill be adding a trans brake and a 6 pt cage and a 9 inch rear. So I want 10 seconds out of this set up no matter what. If i could get mid 11s all day out of the 3.1L, I will be very dissapointed to not get 10s outta a 3500 and considering it will have a t brake.
So here is my list of stuff that i know i will need.
Dependent on the engine, bearings all the way arround
Moly rings
Forged pistons(if i can find them at a resonable price)
new locks and retainers(i plan to reuse my behive comp cam springs)
Cam(can I reuse my 270 split cam i have now if its in fine shape still?)
Throttle body adapter(3500 is drive by wire) im using my 7730 again.
Needless to say im pisssed that i blew it up but also happy because i knew that one day i would toss a lx9 or even a lz9 in this car. SO now is the time to build it up and do it right.
the 270 is a hyd flt tappet cam even if u could use it in the 3500 u wouldnt want to
pm me on the heads and the cam , i think my 3400 has a cracked head as i cant get the cooling system to bleed , and the 270 i could put on the shelf for another 3.4 iron head project
Good point. The 3500s a roller. Another option I had was to use a 3.4 block and toss on 3500 stuff on the top. That would save me from either cutting my k member or changing the oil pan, messing with the engine mounts, and also worrieing about the starter swapping sides.
But i feel that way would take even longer and cost more since then i would need bits and pieces of 2 different engines that i dont have..lol
Ill pm ya dave and anyone else needs some parts off the engine i have let me know. I know its not a for sale section but you know what i have, so let me know. Injectors, heads, intakes, custom length pushrods, stuff like that.
I always replace the oil pumps when buying a used motor. the pump is the heart of the engine. if thats no good, then the rest of the engine dies. I have found that most used or junkyard 60 degree engines suffer from LOPS; low oil pressure syndrome.
Putting in a new pump, I take apart the new pump, inspect the gears, remove any burs on the gears, and shim the oil pressure spring bypass to get me a little more oil pressure. Every 60 degree I have done this too has had 60-70 psi cold and 35-45 hot at idle. I like that oil pressure better than the 25 at idle COLD, I have found in some used 60 degree engines.
Its cheap insurance and gives me a chance to clean out the pan, and inspect the bottom end for anything obviously loose. I have had good results, and in doing this I have lost zero rod or crank bearings even with nearly 2.5 times the factory hp output.
That's something I've NEVER experienced with a junkyard 660. And all but one time that I've seen low oil pressure it's not been because of the oil pump, but worn bearings, and/or leaks. The one time I experienced low oil pressure due to an oil pump was not a junkyard engine, very, very far from it. A very stout 350 that the bypass hung open, and that was only earlier this year that I came across that. The 3500 oil pump is a great oil pump, with the large pick up and works great even on turbo applications, where oil is fed to the turbo. The most I'd consider doing off the hop, if I was worried for some reason is to simply inspect the existing oil pump to see if there's a reason to replace it. To just arbitrarily replace it just because seems like a waste on more than one level.
Originally Posted by fasteddi
Good point. The 3500s a roller. Another option I had was to use a 3.4 block and toss on 3500 stuff on the top. That would save me from either cutting my k member or changing the oil pan, messing with the engine mounts, and also worrieing about the starter swapping sides.
But i feel that way would take even longer and cost more since then i would need bits and pieces of 2 different engines that i dont have..lol
Ill pm ya dave and anyone else needs some parts off the engine i have let me know. I know its not a for sale section but you know what i have, so let me know. Injectors, heads, intakes, custom length pushrods, stuff like that.
For the work you propose to do to the 3500 anyway, the 3.4 bottom end, 3500 top end hybrid would not be that difficult. I like your plan of forged pistons, I would also suggest replacing the rods. I know my experience is kinda the exception, but since it looks like it was a rod failure or a combination of a rod and piston failure that took out my LX9 back in December, I'm a little gun shy to abuse the stock rods, the way you intend to, I still can't really identify some the parts that came out of that engine as rod parts. lol. This is why I'm putting Eagle rods in my LZ9, that I originally purchased to put in an LX9. Luckily I hadn't ordered any pistons before deciding to go LZ9, so I could just move them over to the new build. lol FWIW, the stock LX9 and LZ9 rods are different and the stock LZ9 would likely stand up to a little more abuse than the stock LX9 rod, in part due to the full floating wrist pin of the LZ9, which means that it didn't need any heating for piston and rod assembly from the start. Heating and cooling of a rod can make it brittle.
Using the cam you have now wouldn't be the end of the world, there have been more than a few people go to a flat tappet cam in a gen3 660, simply because they couldn't find an off the shelf roller. However there's a couple sources for them now, so a roller would be a great thing to keep in that engine.
I am having some problems finding forged pistons rods.. exc. Any idea on who sells any? Wot doesn't even show anything which is weird.
probe makes a 3.4 piston , im not sure who makes the 3.5/3500 stuff
i do belive 3.4 shortblock with 3500 upper is ur best bet , i would also venture to say the rwd 2.8/3.1/3.4 rods are stronger then the 3500 rods not sure on the 3900 rods though
there have been alot more rod failures in full swaps then there have been on hybrid builds
I never said the lx9 pump was a junk pump. I said its cheap insurance to replace the pump from a JY engine. Its also cheap ins to replace the pump from any used engine you buy.
I have purchased more than a few 60 degrees and 2 of them had low oil pressure when I didn't replace the pump. Both were low mileage, under 10k. One of them lost a rod bearing and had 30 psi cold when I first got it. The other had 25 psi at idle cold with 10-40 oil.
All the others I replaced and shimmed the bypass spring and had much better oil and never lost a bearing in those engines.
an lx9 will prob require diff engine mounts, and a starter relocate of some sorts. Not a big deal.
but if you go with a 3.4 iron head, and rebuild that, then it should use the same mounts, you can swap the cam, and then since you plan on new pistons for an lx9, you can just do custom iron head forged pistons for a 3400 and then use the aluminum head top end you already have.
if you plan to redo your whole exhaust, and redo all your engine mounts, and do a roller cam, and do a larger tb, you might as well do a 3900. Car part from my previous post had a 42k mile lz9 for $500. Thats cheap. Everything you have to do for an lx9 block, you would also have to do for the lz9 block swap. lz9 has bigger intake ports and valves, and larger plenum and intake runners. Mars is doing 130 traps on 15 psi and no nitrous.
with an lz9, there are aftermarket forged pistons for around $500 if I am not mistaken. I will have to check my notes.
I am having some problems finding forged pistons rods.. exc. Any idea on who sells any? Wot doesn't even show anything which is weird.
No one sells any, they will need to be custom, which is why I'd also spend the money now on rods. The ones I'm using are slightly longer that will improve rod ratio as well
Hit me up on FB when you get a chance, I'll let you in on some of my dark secrets. LOL
Originally Posted by Shaun41178
I never said the lx9 pump was a junk pump. I said its cheap insurance to replace the pump from a JY engine. Its also cheap ins to replace the pump from any used engine you buy.
I have purchased more than a few 60 degrees and 2 of them had low oil pressure when I didn't replace the pump. Both were low mileage, under 10k. One of them lost a rod bearing and had 30 psi cold when I first got it. The other had 25 psi at idle cold with 10-40 oil.
All the others I replaced and shimmed the bypass spring and had much better oil and never lost a bearing in those engines.
I can't explain why you would have seen that, because that's completely opposite of what I have seen. To me replacing anything "just because" is a waste and should inspect any suspect parts before just throwing money at something. EVERY JY engine I have installed has not needed any internal parts replaced, part of that is I buy tested engines when I need to buy a runner (one that I don't plan to build before using).
an lx9 will prob require diff engine mounts, and a starter relocate of some sorts. Not a big deal.
Not possible to move the starter on an LX9, or any transverse 660 for that matter, at least not without also welding a small wedge to the block where the longitudinally mounted starter is located. The FWD block is different in that area. People have moved the starter on transverse engines to the longitudinal location because the block can accept that, but not the other way around. IIRC there was one person that did move the starter to the longitudinal location on a transverse engine, but didn't weld in that missing part (which is missing for transmission clearance reasons), and had issues with breaking starter noses due to a lack of proper support.
but if you go with a 3.4 iron head, and rebuild that, then it should use the same mounts, you can swap the cam, and then since you plan on new pistons for an lx9, you can just do custom iron head forged pistons for a 3400 and then use the aluminum head top end you already have.
I don't quite follow what you are recommending here, but it sounds like you're saying to use iron head piston for a 3.4 (since there's no such thing as an "iron head 3400"), with his 3400 top end. That's great if he was N/A, since the SCR would be up around 12:1, not so great with turbo or supercharger, nitrous might be fun though. lol
if you plan to redo your whole exhaust, and redo all your engine mounts, and do a roller cam, and do a larger tb, you might as well do a 3900. Car part from my previous post had a 42k mile lz9 for $500. Thats cheap. Everything you have to do for an lx9 block, you would also have to do for the lz9 block swap. lz9 has bigger intake ports and valves, and larger plenum and intake runners. Mars is doing 130 traps on 15 psi and no nitrous.
with an lz9, there are aftermarket forged pistons for around $500 if I am not mistaken. I will have to check my notes.
I agree that a 3900 would be the way to go, but the cooling system changes in the LZ9 do add some complexity to swap, and make it difficult to use any existing bracketry for the engine driven accessories. This would have to be all custom. Mars used NLA aftermarket front cover and brackets for his swap, so it will be up to someone to offer something or the swapper to come up with something on their own. I have a few ideas for my own LZ9 swap. So if someone wants to deal with the additional complexity, the pay off will be huge IMO, and worth it. The 3500 is just easier from an accessories and plumbing standpoint, mounts, oil pan/crossmember, crank trigger and starter location issues are pretty much the same issues to deal with between the LX9 and LZ9.
I'd like to see these $500 forged LZ9 pistons, because AFAIK, there isn't any. LS1/6 pistons are the same diameter but don't have the (correct) valve reliefs, and have a different pin height requiring custom rods to use them. This is why I'm going with an off the shelf rod (for a different application that's very close) and getting custom pistons. I figure use as much off the shelf as I can will help keep costs down and make any later repairs, if any should occur, easier.
I can't explain why I saw low oil pressure on the engines I got, but thats how it was when I didn't put a new pump in a shim the relief spring. all I can do is share my experiences.
so you spend $500+ on a engine, then you do new gaskets, new pistons, regapped rings, pull the heads, etc etc. spending $50 for a new pump is TOTALLY worth it. its not a unnecessary expense. If you feel so thats fine. I don't think it is, and once again, its cheap insurance for the amount of money AND time you are going to put into the swap, just to have low oil pressure.
I apologize as I wasnt' clear with my wording. if he goes 3.4 iron head block, similar to his 3.1 iron block, and rebuilds it, then he can use the forged pistons WOT sells for its aluminum head 3400 motors with custom valve reliefs, then use his current heads and top end he has to complete the engine. Nothing as far as mounts, or coolant need to be changed. Its prob the easiest and most bolt in option available, esp since eddi claims to be tearing down the lx9 anyways.
I will have to go back and check my notes but I think the pistons I found for the lz9 were forged. I found them on summit, and shared the data with MArs. maybe they were Hypers, but either way, it was a cheap bolt in lz9 piston that has a good CR for boost. It also had the correct pin diameter and compression height.
certain ls1 piston share the correct pin dia and CH as the lz9 so off the shelf pistons are available. trust me I have researched extensively. when I get some time I will post up that data.
I can't explain why I saw low oil pressure on the engines I got, but thats how it was when I didn't put a new pump in a shim the relief spring. all I can do is share my experiences.
so you spend $500+ on a engine, then you do new gaskets, new pistons, regapped rings, pull the heads, etc etc. spending $50 for a new pump is TOTALLY worth it. its not a unnecessary expense. If you feel so thats fine. I don't think it is, and once again, its cheap insurance for the amount of money AND time you are going to put into the swap, just to have low oil pressure.
I guess that's where I differ. I'd never spend $500+ on an engine (60 degree anyway) that I planned to pull apart and replace the items you list. If I'm spending that much, it's a known runner with a warranty, so no need to even inspect anything really. I bought my LZ9 for $212 CDN taxes in, that's about $163 USD at today's exchange rate (I bought it back in February), when I believe the exchange was even higher. Plenty of sub $300 LZ9s around here too.
I apologize as I wasnt' clear with my wording. if he goes 3.4 iron head block, similar to his 3.1 iron block, and rebuilds it, then he can use the forged pistons WOT sells for its aluminum head 3400 motors with custom valve reliefs, then use his current heads and top end he has to complete the engine. Nothing as far as mounts, or coolant need to be changed. Its prob the easiest and most bolt in option available, esp since eddi claims to be tearing down the lx9 anyways.
Yes that would be the easiest upgrade path. This makes what you posted earlier much clearer. This was a similar recipe I had for my Jimmy many years ago, but since the gen1 3.4 was only a few years old at the time, they were difficult to find cheap. And I wasn't about to spend $700+ (at the time) on what was essentially going to end up being a block and crank, maybe a set of rods for my build. Everything else was going to be replaced. That's when I built the Franken60, that started as a gen1 2.8L block and ended up at 3.2L overall, with early gen 3 top end, I should have went with the 3400 top end I had sitting there... oh well, hind sight and all that.
I will have to go back and check my notes but I think the pistons I found for the lz9 were forged. I found them on summit, and shared the data with MArs. maybe they were Hypers, but either way, it was a cheap bolt in lz9 piston that has a good CR for boost. It also had the correct pin diameter and compression height.
certain ls1 piston share the correct pin dia and CH as the lz9 so off the shelf pistons are available. trust me I have researched extensively. when I get some time I will post up that data.
I haven't looked extensively, but I did look and have only found links to custom forged piston manufacturers. I can believe hyper pistons being available, but that's only a step sideways not up IMO. The stock pistons will be the same (likely) and are likely only stock replacement pistons if they are offered as a direct fit for the LZ9. Besides to me that means you either need to keep the stock rod, or get a custom rod made, since I also haven't found any direct fit aftermarket rods for the LZ9. I know others have had good luck with the stock rod, but when one plans to abuse the engine as much as I do and assume fasteddi wants to, the stock rod would be one of the first things on my list to go and actually was the first thing I bought for my current build.
Even if certain LSx pistons have the correct compression height and wrist pin diameter, they still lack the correct valve reliefs, that require them to then be cut into the piston, which may or may not weaken it in key points. Not every engine shop will want to do this either.
Last edited by Six_Shooter; 05-27-2016 at 12:06 AM.
03-16-2016, 03:04 PM
