Used engine options - eventual forged build
Used engine options - eventual forged build
Hey all... So my kswap is crap and am now looking at what's next. While I was really hoping the K24 would work to provide a fairly unique car.. not to be. So now back to a BP.
Want to pick your brains on a couple ideas around next steps. The goal is still a build that makes the car fairly unique while being a good street car, I'm considering a high compression, low boost engine or possibly even a stroker kit (less likely). But either path, I have the same questions...
The first is about used engines. I have a line on a 110k mile Mazdaspeed ($2500), or a JDM BP5A with a 6 speed ($2900) with about 60k miles, or a very sketchy block that rotates, but hasn't run in a while ($650).. Which option would you start with? Any other options I should look for?
The other question is about the used engines ( Mazdaspeed or JDM ). If I go that route and decide to run it as is for a while before building it or maybe another... Is there any value in tearing down the engine and putting it back together? It would help me learn the engine and also inspect it. Or does that just introduce more risk??
Thanks
Want to pick your brains on a couple ideas around next steps. The goal is still a build that makes the car fairly unique while being a good street car, I'm considering a high compression, low boost engine or possibly even a stroker kit (less likely). But either path, I have the same questions...
The first is about used engines. I have a line on a 110k mile Mazdaspeed ($2500), or a JDM BP5A with a 6 speed ($2900) with about 60k miles, or a very sketchy block that rotates, but hasn't run in a while ($650).. Which option would you start with? Any other options I should look for?
The other question is about the used engines ( Mazdaspeed or JDM ). If I go that route and decide to run it as is for a while before building it or maybe another... Is there any value in tearing down the engine and putting it back together? It would help me learn the engine and also inspect it. Or does that just introduce more risk??
Thanks
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Have you considered ecotec? New kit has some great promise, and company is under new owner ship so much better support. Engines are ~$600 for a 2.4, 170-180hp. Works well with boost too. OE DBW, super cheap parts. Anyways.
If k-swap wasn’t your jam, I under stand the want to go BP. I’d suggest a KISS strategy, do a rods only build with a 2560 making ~260-280. Adding high comp or stroker just complicates what sounds like already a bit of a headache of a build.
MSM is great, but you’re really paying for an oil cap, valve cover, and turbo kit that’s only good to 200-210.
Id personally probably start with the $600 block, reseal/rebuild with forged rods, new rings, and a refreshed head.
If k-swap wasn’t your jam, I under stand the want to go BP. I’d suggest a KISS strategy, do a rods only build with a 2560 making ~260-280. Adding high comp or stroker just complicates what sounds like already a bit of a headache of a build.
MSM is great, but you’re really paying for an oil cap, valve cover, and turbo kit that’s only good to 200-210.
Id personally probably start with the $600 block, reseal/rebuild with forged rods, new rings, and a refreshed head.
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Senior Member
Joined: Mar 2017
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From: GER
That's what I'd do. I don't trust used 25 year old engines anymore. Rods only is a reliable street setup at 250-300hp, if you have a good tune.
Nothing unique there, but easy to do and a lot of fun.
Nothing unique there, but easy to do and a lot of fun.
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Joined: Jul 2014
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From: Canberra, sort of
I'm not sure I agree with Curly about the MSM being 'great' - it is the easy button, but ...
It's a dog really, nice shiny coat, but a dog all the same. The IHI turbo is small, the engine has the weak rods, and the FMIC is laughable (as well as a rust issue inside). You are going to be spending money, so start with a similar engine that is cheaper. The only thing going for the turbo itself is its cheapness as a used item. So buy a cheap engine, do the rods (and oil pump?), add the cheap turbo and you are on your way - everything else can be added/changed as inclination and budget allows, but you have a very sound base to work with. Or skip the IHI and go with a Garrett knock-off (I did).
It's a dog really, nice shiny coat, but a dog all the same. The IHI turbo is small, the engine has the weak rods, and the FMIC is laughable (as well as a rust issue inside). You are going to be spending money, so start with a similar engine that is cheaper. The only thing going for the turbo itself is its cheapness as a used item. So buy a cheap engine, do the rods (and oil pump?), add the cheap turbo and you are on your way - everything else can be added/changed as inclination and budget allows, but you have a very sound base to work with. Or skip the IHI and go with a Garrett knock-off (I did).
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You described building an engine and then mentioned two engines. Both are going to be rebuilt so, start with the cheaper one? You need the crank and block to be good. You are going to be replacing the pistons, boring the cylinders, and putting forged Chinese rods in it.
You should be having the head cleaned up, the valve guides checked, the valves done, and new stronger springs put in it.
I don't understand the interest in higher static compression ratio because it will hurt your ability to run optimal spark timing, but whatever you want to do. If you run a quarter PSI more you will more than make up the difference and be able to use a superior spark timing map. You will also have headroom for when your goals change, rather than being artificially limited.
You should be having the head cleaned up, the valve guides checked, the valves done, and new stronger springs put in it.
I don't understand the interest in higher static compression ratio because it will hurt your ability to run optimal spark timing, but whatever you want to do. If you run a quarter PSI more you will more than make up the difference and be able to use a superior spark timing map. You will also have headroom for when your goals change, rather than being artificially limited.
The reason for the more expensive options is just in case the consensus was that engines known to have run come with less risk of being bad. But if people with experience feel the rotating block should be just fine to start. Then I'll do that.
As for the high compression, this is 100% a street car, which may or may not see some hpde or auto-x (likely not). I really want it to be responsive off the line. But I do agree, it's probably better to just stick with 9:1 to allow room to grow.
What are your thoughts about a first timer doing an engine build? I think with the help of the machine shop, I can figure out the bore. But valve lash and cam timing upon assembly has me "slightly" concerned.
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Have you considered ecotec? New kit has some great promise, and company is under new owner ship so much better support. Engines are ~$600 for a 2.4, 170-180hp. Works well with boost too. OE DBW, super cheap parts. Anyways.
If k-swap wasn’t your jam, I under stand the want to go BP. I’d suggest a KISS strategy, do a rods only build with a 2560 making ~260-280. Adding high comp or stroker just complicates what sounds like already a bit of a headache of a build.
MSM is great, but you’re really paying for an oil cap, valve cover, and turbo kit that’s only good to 200-210.
Id personally probably start with the $600 block, reseal/rebuild with forged rods, new rings, and a refreshed head.
If k-swap wasn’t your jam, I under stand the want to go BP. I’d suggest a KISS strategy, do a rods only build with a 2560 making ~260-280. Adding high comp or stroker just complicates what sounds like already a bit of a headache of a build.
MSM is great, but you’re really paying for an oil cap, valve cover, and turbo kit that’s only good to 200-210.
Id personally probably start with the $600 block, reseal/rebuild with forged rods, new rings, and a refreshed head.
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Replying to you in this thread, as I'm asking for the other to be deleted.
The reason for the more expensive options is just in case the consensus was that engines known to have run come with less risk of being bad. But if people with experience feel the rotating block should be just fine to start. Then I'll do that.
As for the high compression, this is 100% a street car, which may or may not see some hpde or auto-x (likely not). I really want it to be responsive off the line. But I do agree, it's probably better to just stick with 9:1 to allow room to grow.
What are your thoughts about a first timer doing an engine build? I think with the help of the machine shop, I can figure out the bore. But valve lash and cam timing upon assembly has me "slightly" concerned.
The reason for the more expensive options is just in case the consensus was that engines known to have run come with less risk of being bad. But if people with experience feel the rotating block should be just fine to start. Then I'll do that.
As for the high compression, this is 100% a street car, which may or may not see some hpde or auto-x (likely not). I really want it to be responsive off the line. But I do agree, it's probably better to just stick with 9:1 to allow room to grow.
What are your thoughts about a first timer doing an engine build? I think with the help of the machine shop, I can figure out the bore. But valve lash and cam timing upon assembly has me "slightly" concerned.
I run about 10:1 or so, 30+ psi no problem, and no intercooler either... But I run 100% methanol, and a very large turbo, so my motor doesn't see a lot of boost below 5K. I don't think I could (or, at least I would not) do this on E85, and definitely not with a small turbo.
Pulling off a high compression build is much more difficult, so yeah, for 95% of people, you'll be better served with a lower comp motor unless you have the octane and knowledge on how to put together a setup.
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I’ve heard/experienced more issues on stroker cranks than not, but maybe there are better kits out these days. I’d crack(void?) test a block and go 85-86mm pistons before I went stroker, if I was keeping a BP.
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Joined: Mar 2017
Posts: 804
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From: GER
Keep hydraulic lifters, don't sleeve a BP - just bore, let the machine shop do the exhaust guides, intakes are more than likely fine, let them clean up the seats/valves and you are good to go. If you are concerned with setting timing, you absolutely need someone that helps you out big time with this whole thing, but it's doable, take your time
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Keep hydraulic lifters, don't sleeve a BP - just bore, let the machine shop do the exhaust guides, intakes are more than likely fine, let them clean up the seats/valves and you are good to go. If you are concerned with setting timing, you absolutely need someone that helps you out big time with this whole thing, but it's doable, take your time
Also why no sleaving? What's wrong with a that especially if you overbore?
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