Jump to content
HybridZ

Blown (as in kablooie) L24


wondersparrow

Recommended Posts

Well, as much as the car seemed to run great, I appear to have blown the L24 in my track car. Cylinder #2 has a lot of oil in it. I am guessing it is the piston rings as it got worse when I warmed up the engine, but its possible the valve seals are just that toast. I had't really done anything with the engine, so this was pretty much expected. As my project cashflow isn't as good as some, my attitude was to leave it as the PO had it setup and when it died, do something about it.

 

That being said, I am faced with some choices. I like to do nutty things, and for some reason I think it would be fun to be the retard that keeps an L24 in his race car. There are 2 reasons for this. 1- it should be cheaper as long as the parts are in decent shape &; B- I can stay in GT3. There are some pretty big money GT2 players in the area (people that can afford multiple Rebello engines in a season), and I just don't think I can compete.

 

My questions are, how strong can a well built n/a L24 be (I have trip Weber 45's already)? Would it even be worth it? I get the impression that a noob willing to invest the time and diligence can build a decent engine, would you guys agree? of course I would use a reputable machine shop to do any machining/balancing/etc, I am really just wondering about assembly.

Link to comment
Share on other sites

I clicked on this hoping someone put a blower on an L24 :mrgreen:

My condolences. I'll bet an L24 w 3web could put out some serious power. I'll bet you would be able to attain similar HP as an L28, just at a higher RPM. Get that engine balanced really good and let it sing.

Link to comment
Share on other sites

There, changed the title to be a little more clear.

 

The engine was a hoot while it was running. It seemed a little low on power, but who knows how long I have been running it in L5 mode. As long as I can do something about those dang tweaked Miatas running away from me on the straights, I'll be happy. Yeah, Miatas. /me hangs head in shame. Every time, catch them in the corners, and watch their tail lights on the straights.

Link to comment
Share on other sites

Might be able to fab up some spacers to run with the 3webs to increase the runner length. That will drop your torque band down some. I have SUs on my L28 and have thought about doing that. There's already about 3/4" spacer that I'm not sure if it's stock, or something the previous owner added. Are you allowed to do that kind of mod in racing..?

Link to comment
Share on other sites

With 45s you're can easily make 250hp with the L24. Spend your money on some 12 to 1 forged pistons, good head porting, large valves, and a 300+ duration cam. Source the rods with the 9mm bolts and spend money on reconditioning them and making sure the crank is in great shape. New Nissan rod and main bearings, turbo oil pump, and a good sized oil cooler will make sure it lasts for a while.

  • Like 1
Link to comment
Share on other sites

I currently have a well ported E88 head. Would that play well with those pistons or is that too much compression?

 

What kind of fuel would I need? I am assuming pump gas is out, would would VP111 be enough? I have been cutting the VP111 50/50 with some 94 octane ethanol blended pump gas with the current setup and it seemed to be working well. Then again, I turned cylinder #2 into a big oil pump, so maybe it wasn't enough.

Link to comment
Share on other sites

I would think that VP111 is doable. There are people running 11:1 on pump gas. Just buy a little and see what the minimum octane your motor will run on and use that, maybe a little more octane to prevent detonation. If I were to run VP111 in my street motor, sure it would work but it takes more BTU's to ignite higher octane, thats why you go with the minimal amount and thats why those octane boosters don't work worth a **** for the ricer kids.

 

Do you run Marvel Mystery Oil or Castor Oil in your fuel by any chance?

 

You should do it just for the smell if you don't already. :P I love it!

Link to comment
Share on other sites

I have been looking around, and can't seem to find high compression pistons on the "shelf" anywhere. I don't mind paying for custom pistons to make some decent reliable power, but this will be the first time form me. Can anyone recommend a brand that that won't break the bank? I have seen some as high as $900 per piston and thats just not going to happen as long as I am working for a charity, hehe. Maybe its time to get back into project management :P I am hoping to keep the rebuild under $3k. I will do most of the dirty work myself to keep the costs down. Once I get my garage cleaned up (from the sanding and painting); I'll tear into this engine and see what I have to work with. I am sure some of the parts are going to be reusable (ie, I am guessing there are likely 9mm rods in there already).

Link to comment
Share on other sites

The castor oil and marvel mystery oil in the fuel is for top end lubrication. On British cars they even make a kit thats like a 1 quart reservoir with a hose from it. At the end of the hose is a needle so a bunch of oil doesn't spew out. Then you fit the needle to a spot on the manifold where it draws vacuum. The vacuum sucks the oil in so you don't have to add it to your fuel.

 

When it burns it has like a sweet smell to it, I like it.

 

Oh and little model airplane engines and old rotary style airplane engines had castor oil in it too.

Link to comment
Share on other sites

  • 5 months later...

Well, the car sat all winter. I finally got around to pulling the head the other day. No major defects in the gasket. I think I would have been happier if I saw a big void in the gasket indicating how it failed, but no point in being too concerned. There were a couple of coolant passages blocked with some crusty black crap. Maybe rust, maybe something stupid like stop leak. After cleaning everything up, I realized that the head has had some serious work done. It says its an E88, but its not like any E88 I have seen. The chamber is largely welded up. I took the head in to get resurfaced and had a couple chambers cc'd. They turned out to be 40.2cc.

 

P1010811.JPG

 

The pistons come up about .75mm above the deck and have some pretty deep (2.7mm) fly-cuts. It also looks like it has been bored out to 84mm. Note that I don't have any proper micrometers, these measurements were taken with digital caliper.

 

P1010813.JPG

 

All in all, I was pleasantly surprised when I cracked into my engine. I pretty much just bought it, changed the fluids and ran it. I see no markings at all on the cylinder walls. There is no crosshatch left, but no scoring either. I picked up a set of arp studs and I think I am going to just toss in another felpro gasket in and see how it goes. I don't know what caused the head gasket to go in the first place. Was the head gasket and the crud the cause of my heat issues, or will that still be an issue. I guess time will tell.

Edited by wondersparrow
Link to comment
Share on other sites

Wow... you got yourself some awesome luck there... was the engine ever in a JDM car by any chance?

That cylinder head looks awefully like the type of treatment they give heads in japan, I've seen some examples of people doing it in the states (ie monzter, braap and so forth) but it seems much more common in jap stuff... I've seen lots of examples of this beening done with n42's and only one e88 before... more rarely e88's but it'd suspect it was probably done using an l24-spec head to avoid the inspection nazis they have over in japan.

You've got yourself a very nice head: big money spent to get it that far.

I certainly wouldnt mind the pistons either... rods are probably forged; worth checking. If you dont want any of it I'd be happy to take it off your hands :P

 

cheers,

-pete(green with envy)

Link to comment
Share on other sites

If I am not mistake, there was an "early E88 head" which had chambers all but identical to the E31 heads; peanut shaped, just like what we see here. I do not know if I have ever seen one of these personally, and this head looks like it has probably been worked over even if it IS this "early E88" because the chamber side of those valve seats just doesn't look factory (ie the valve shrouding) and it also looks like there might be an awkward ridge to provide a hot-spot for unwanted ignition. I would definitely consider re-ringing, re-honing, and having a 3 angle valve job done on the head if this is a GT2 motor.

 

Just out of curiosity, what do the ports look like on this head? It certainly looks like a nice motor you bought.

Link to comment
Share on other sites

If I am not mistake, there was an "early E88 head" which had chambers all but identical to the E31 heads; peanut shaped, just like what we see here. I do not know if I have ever seen one of these personally, and this head looks like it has probably been worked over even if it IS this "early E88" because the chamber side of those valve seats just doesn't look factory (ie the valve shrouding) and it also looks like there might be an awkward ridge to provide a hot-spot for unwanted ignition. I would definitely consider re-ringing, re-honing, and having a 3 angle valve job done on the head if this is a GT2 motor.

 

Just out of curiosity, what do the ports look like on this head? It certainly looks like a nice motor you bought.

 

I really dont know about the "early e88" chambers... i mean, i've heard them mentioned alot but i've never seen a photo of one... on the other hand, i know for a fact there is a late e88 with a very closed chamber desing, i know this as I have two of them :). I'm building one up and will get photos on one of these days but in the meantime i can tell you that the chamber seen here is not significantly similar to that one.

 

The "custom head building" sticky reveals some heads with similar CC designs... I would fathom to guess that this has received a similar treatment...

Mark: "after-market rods".... ya-kno-wut-i meant :P

Edited by kolonelklink87
Link to comment
Share on other sites

"Inspection Nazis" in Japan couldn't care less what head is on your engine. Shaken-Sho ONLY verifies block number.

 

If you have an L20B in there, it passes, because it's an L20 (A)...

 

Same for Celicas and Trueno's. I knew plenty of guys with "2T" or "18R" engines, which clearly were originally SOHC or PUSHROD engines that did the 2T-G conversion, or 18R-G conversion (or for the more arcane, the 2T-B or 18R-B which were dual two barrels with progressive secondaries.... or even SU's...)

 

As long as that block said 2T, or 18R, it didn't matter that the engine was now a 145HP 18R-GR from a 1973 Corona GSS or the original 18R-C that was in there originally. Ask me how I know. Ask me which car I lost my license driving... B)

 

As I have said over and over: head casting flow numbers are pretty irrelevant, you're going to rework it totally if you're racing anyway, so get the best one with the least corrosion.

 

Case in point: the engine we have here!

 

I would disagree with the octane selection advice given earlier. For a race car I would NOT 'run the least octane you can'... If I could get 120 octane for the class and legally run it, I would. Octane is margin. If you play games with cheaping out on your fuel, your 'economy' will soon be rewarded with a bill for new pistons, and possible a rod, or a block, etc etc etc...

 

At Bonneville, we are restricted to running ERC fuels, as they are a 'sponsor'---guess what fuel we tune with? What we run on the dyno? Sure, we can make more HP on better VP fuels while running at El Mirage. But many who do that get sad wakeups when they get to Bonneville and have to run the ERC and then start guessing what changes they need to make to keep their engine held together for at least 10miles at top rpms....

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...