SCCA EMod MGB GT V12 Build

Briget and my best laps, side by side. I was 2 seconds quicker and I think all of made up on one very fast straight were I put the hammer down

first is this boost acceptable for this engine ? and why the big fluctuation on Opress? oh and maybe you should sport fingernail polish too ....might make you even quicker, you said six seconds over the next closest....woof. Hey who is the 10 time emod champ??? he better be sweatin' readin your numbers........

In reply to 759NRNG:

On the dyno, the engine makes 25 psi of boost and that's fine for this engine. LHU's are reliable up to 400 hp on stock parts. I ran a 54.0 on the test course and Briget ran a 56.0. The other cars were all 60+ until Ron Ver Mulm went out and ran a 56.0. He came in 3rd last year in EM and is a good yard stick. I don't know if he ran again later and got quicker but Briget feels pretty great that she matched his time. The LHU has an oil pump that is computer controlled and it varies wildly depending on rpm.

"The LHU has an oil pump that is computer controlled and it varies wildly depending on rpm." What?!?!?!! is there still a mechanical drive with press regulated by a solenoid/bypass valve thingy??? Can't grasp this concept.....not really down with throttle by wire either(my 04 bravado) sheesshh

The pain continues, all my reliability from last year has been lost. I did a compression test and the cylinders were all 150 psi exactly, which is good. I also put a stethoscope on the engine and the noise appears to be coming from cylinder #3. I pulled the pan and there were little flecks of chrome in the bottom, I suspect these were from a piston pin. My options are to rebuild this motor, buy another running motor or buy a shortblock from ZZP. The cheapest is rebuilding this motor but it's a complex piece and I have not been able to secure detailed info on the proper procedure. I purchased a factory GM shop manual but it's not here yet. I successfully rebuilt an air cooled 911 motor years ago but had the benefit of a manual. The only way I can afford this setback is because I just sold my Ayrton Senna bike, thank God. [URL=http://smg.photobucket.com/user/loosecannon/media/MGB-GT/IMG_9102_zpsdagwyzbo.jpg.html][/URL]

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In reply to loosecannon:

Wow, that really sucks.

Dude...this is not hopeless , you will now enter the nether zone known as MazDR63 engineus rebuildicus. You mentioned a piston pin, I'm guessing #3 rod bearing, cuz with the noises you described it reminds me of the 4.2L in my Bravada that made the same sounds. Hand tough!

I have been so stressed out since this all happened because I couldn't decide what to do. Rebuilding this one with forged pistons and better rods would be around $1300 and to do it right, I have to wait until the shop manuals I ordered arrived. A rebuilt shortblock from ZZP is $1500 and if I wanted upgraded pistons/rods, it would be over $2000. A complete, used motor from EBay ranges from $1000 to $2500 depending on mileage. I decided to go with an EBay motor so I found one with low miles, out of a twin car to what my engine came out of and for only $1500. I will put that in the car with the new oil pan and Accusump and pray I don't have the same problem. I will rebuild the damaged motor and keep it as a complete spare because eventually I'm going to need a new motor if I race this one long enough. The motor and the pan should be here next week.

Loose, all things considered, would the LHU still be a consideration when searching for suitable power plants for the P? I actually like the baseline hp & lb/ft for this not to mention it's physical size. The LHU would look way good in the nose of my B-GT, sporting Sebring corners. Anybody need a 215ci olds V8 in need of a complete rebuild?

At $1500 per, I would consider the engine to be a consumable. That is a pretty cheap race engine.

NOHOME wrote: At $1500 per, I would consider the engine to be a consumable. That is a pretty cheap race engine.

Given the time and parts cost to rebuild one, I'd agree.

Still have to diagnose what went wrong to prevent it in the future. Don't pull a Honda.

I have been very happy with the LHU and wouldn't consider anything else for this car. The engine failure was my fault and hopefully it is corrected now. The new engine is scheduled to arrive today and as soon as it hits the shop, I'll move stuff over and put it in the car. I'm supposed to leave for SpringNationals next week so I should be able to do what I need to do to be there, ready to fight the big dogs. As a precaution, I will be pulling back the redline on the engine a little bit but that's ok, this engine makes big power down low. I'll sleep a lot better once it's bolted in and running.

What pray tell did you discern to be the cause for the old bullet? Is it able to be repaired as a spare? Good luck as always and watch those knuckles.....

Hopefully it goes smooth and is all back together for nationals! $1500 is pretty damn cheap for a modern engine really. Are you thinking it was just oil starved in a sweeper or something?

In reply to 759NRNG:

I do not know what specifically is wrong with my motor, only that something is wrong and will only get worse if I keep racing it. I will disassemble it when I get the shop manual that details the proper way to pull it apart. I plan to rebuild it with better parts and keep as a spare. As far as I am concerned, there are only two possible causes of the problem: the brief overheating at the first event or sustained high G's in Lincoln. The new motor just arrived and it looks pretty beat up on the outside but has great compression on all cylinders-at least that is what is written on it, I will confirm tomorrow.

Well ,the other bullet is right there for the taking (beat up outside stuff). Was bumping the redline another possible contributor?

In reply to 759NRNG:

Perhaps. ZZ Performance claims that if you rev above 7000, you need a new damper. I was revving to 7100 but plan on pulling that back to 6900 for this motor.

Just when I thought things couldn't get any worse, I opened up the EBay engine and found broken parts and rust. [URL=http://smg.photobucket.com/user/loosecannon/media/MGB-GT/IMG_9217_zpswgredgkt.jpg.html][/URL]

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I was beside myself over this set back and just started to pull my old motor apart to see what was wrong with it. I found that the main bearings are nearly perfect but #1 and #4 rod bearings are shot.

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So, in 7 days I am supposed to be headed for Lincoln, Nebraska for Springnationals and I have run out of options but to Roadkill this motor and run it. I am throwing rod bearings in it and hoping for the best.

Wow, that is just E36 M3 of the highest order! How does a chain just... ...I can't even.

Well, berkeley.

Ouch! That stinks.

I'm never buying powertrain bits from ebay again. I bought a great engine, then a reman trans that died in 2 weeks, reman heads that were bad, and a rear axle that had water in it and failed because fine rust ate the bearings even though I cleaned it as well as I could. Last straw was an engine that was advertised as one RPO code but it was different and not compatible, which wasted two trips to freight dock since i had to send it back

berkeley ebay sellers, check car-part.com

In reply to patgizz:

eBay engine buying scares me. Any mail order shipped by freight truck scares me. Although, lots of things scare me.

I'm so glad I have importers within reasonable driving distance for when I buy the 2JZ for Uncle Ben.

Oh that sucks.

The ebay motor was out of a flood car.