Barn Find Race Motor rebuild.

[Nate SERE]

I found an old race motor and was able to talk the owner into letting me take it off his hands.  It was originally bought from Coast Corvette in Anaheim.

 

The valve cover is stamped trident engineering

 

Owner said that when he raced it, it was a "Cobra Killer" and would just smoke the tires on street tires so its only for racing. 

 

When he got the motor it has a dry sump oil pan on it.  (I have the pan now, dont really need it so if anyone needs it, let me know)

 

There was no carb or intake so he had triple webers 40's custom built for the motor by a race shop in CA.   It has a Cannon manifold.

 

He put ARP headers on it and a 2 inch straight pipe to a monza exhaust. 

 

The motor has a N42 block with E88 head that are race prepped by Solvers porting S.V.

 

It supposedly has Carillo rods.  

 

He said that he was able to run it on street gas so hopefully the compression isn't too high.

 

He said that he blew a ring because the valves were adjusted too tight.  

 

That is all the info that I have from the previous owner.   Here are some pics of how I found it.

[Nate SERE]

Here are some more pics from when I went to get the motor....

[Nate SERE]

webers

[Nate SERE]

dry sump oil pan...

[Nate SERE]

Could we have a blown head gasket and not a bad ring??????

[Nate SERE]

parts

[Nate SERE]

tiny flywheel

[Nate SERE]

Got it home and inspected the head. 

[Nate SERE]

Cam is Electromotive 02 "L-4"

 

I have found conflicting info on this cam. 

 

specs 580/391, valves are adjusted at .010 cold.
Intake timing:
open 37 before TDC
close 61 after BDC
Exhaust timing:
open 61 before BDC
close 37 after TDC

 

Also found

 

it's 278/580, that 391 is the "cam lift", these are the "L4" specs.

 

Also:

 

Ok, I found both specs. You will be able to tell which one it is for sure if you get a dial indicator on it and just check the lift. Its probably the L-4-02. It was generaly considered the best steel valved cam. Not as aggressive a lobe profile as the L-3-04, which was best with ti valves. These specs were taken at .050 valve lift with .008 & .010 clr. We would slightly advance or retard the cam depending on the track length, and carb configuration, and specific engine specs. Since the L-4 was considered a "torque" cam we set them up with anywhere from 1/2 to 2 degrees advance. The L-3-04 was the high rpm cam and we got best results with 1/2 to 3/4 retard. Depending on where it was set, the L-4 cam ran out of steam around 7800 to 8000, while the L-3 cam pulled to well over 9000. Both cams were popular in old C-Production/GT-2 cars.

L-4-02 Electramotive
Int. Lift .562
I.O. 22 btdc Duration 247 degrees
I.C. 45 abdc Int. lobe center 101.5

Exh. Lift .552
E.O. 46 bbdc Duration 246 degrees
E.C. 20 atdc Exh. lobe center 103

In this configuration, this cam would be 3/4 degree advanced.

Edited July 28, 2014 by Nate SERE

[Nate SERE]

Got it on the stand tonight and drained the oil, then flipped it over to take the oil pan off.....

 

Oil came out of where the head gasket was sticking out. I'm hopeful that the head gasket was blown and that the rings are all still good.

 

Oil also came out of one of the other cylinder ports.  Is this an issue?

[Nate SERE]

Looks like a stock crank.  No idea if its been modified.  Can anyone help me ID the rods?  I was told that they were carillo rods.

[Tony D]

Those are not Carillo Rods, those are weight-balanced stock Datsun Rods. 

With the carbs and that flywheel, likely that would not be a streetable combination. The L4 Cam is not that radical, I know people with L4's on the street  today. I would agree with what you found, our L4 peaks at 7,800 as well. It IS a streetable cam with a 11-15# flywheel and conventional pressure plate on it, those it will tone down the hair-trigger response of the throttle from the low-inertia clutch assembly... 

 

ITB's or EFI would likely make that cam idle easily at 900rpms. On carbs, 1,000-1,300. Lower with 40's than with 45, 48 or 50's. It's not really needing 50's for power, 44's would be nice though. 

 

The head is a nice piece from Slovers, and the prep work looks proper for what it is. I doubt the block was done at Slovers, it's  not their bag. It's conventional prep work, and my suspicion would be that "Trident Engineering did the block and farmed the head out to Slovers. It's common, they're good on the L-Heads. It's strange that the crank pulley has the dry sump drive on it, and you have the pan...but not the pump and accompanying components. Usually you just don't 'swap over' from dry to wet sump like this... Generally on a Dry Sump the vent in the side of the block is plugged, yours has the tube. Probably there was some parts laying around that they threw in, and the pulley made its way onto the block... The filter rarely is on the block with a Dry Sump, and the in-block passages are not used on the suction side at all.

 

You are correct, the crank is a Nissan unit, likely balanced with the rod and reciprocating assembly you have on it. That should be fine to over 8,500 rpms. It was on our car. There's another engine with all I describe (but 14.75:1 Compression) up for sale in Clairmont right now...

 

Your head gasket is blown, likely it detonated and it's possible the ring lands cracked. A compression check would tell. But to do that you have to pull the head to fix the gasket...just as easy to dump the piston on the blown cylinder and inspect at least that one closely before any reassembly.

Determine compression ratio, and if you want to run it on the street, likely you will have to cut the domes on the pistons. I would be surprised if they aren't pop tops. Welded E88 Chambers will only get you so much on flat tops.

[Nate SERE]

Wow, thanks for all of the information!

[Nate SERE]

A lot of people have told me that I would not be able to run this engine on the street the way that it is.   Outside of compression ratio, why wouldn't this be a streetable motor?  

 

What is wrong with the flywheel and clutch that is on there now?

[johnc]

The engine appears to be built for road racing, which means it is probably lacking low end torque and power.  Some people have trouble driving an engine like that especially with a lightweight flywheel.   You'll need 2,000+ rpm to get it moving from a stoplight and that gets irritating.  I drove my race engine on the street a few times and it attracted a lot of attention, including a motorcycle cop who heard it from 1/4 mile away as I pulled away from a light.  He turned around to find out what was going on.  Luckily no ticket or impound.

 

Real race L6 engines dont like anything below 4,000 rpm and multi-disc clutches like the one that appears to be on that engine are either in or out.  Slipping these clutches tends to destroy them quickly, depending on the clutch compound.

[Tony D]

That's a big part of it. Carburetors need vacuum to work, whereas EFI not so much. Our bonneville engine wouldn't idle below 2200 rpms with one carburettor, and 1700 with another  set. Change over to ITBS from TWM and an Electromotive EFI and the thing would idle at 450 rpm if we wanted, and even with the tilton multi disc, it would idel smoothly at 900 if we so chose. But you touched the pedal, sneezed on it, and the engine went from idle to 4500.

 

Like John said, it 'came on' above 4000 rpms. With the lightweight flywheel it was hard to get moving. Pushing it in the staging lanes at the drags kept it from overheating the slipper discs. It's  not meant for smooth engagement.

 

But a nice heavy mcloed and a 15# flywheel with decent inertia ring, while it will soften the violent acceleration you would get with the multi-disc would tame the engagement and movement on the street.

 

It would be 'mushy' below 3500/4000 rpms. This is why the L4 makes for such a nice turbo grind when set on the right LCA and opening event... your boost comes on well below where the cam comes alive, and the 2-3 psi you get by going WOT helps torque and breathing down low to make it streetable and on boost you're already pulling hard when the cam comes on and you go "oh sh*t!" the third time! Fourth time is when you pass 7,000 and it's still pulling, and you thought Turbos died off at 5,500!... But I digress....

 

The car will feel mushy below that point, mostly because of how hard it pulls starting there. You will still have more power than the stock engine at that point because of better compression...it just FEELS slower. Curiously, driving it like this, nobody refers to it as "Camshaft Lag" like they do when they lug a turbo engine... again I digress...

 

Generally that is why they are 'unstreetable' --- get a tractable Alpha-N Blend EFI on them, and a decent weight flywheel with good marcel and facing to allow a smooth start and you can get the car moving. Especially if it's geared properly. You need the right gear, and that may be a 4.38... big exhaust (like John C says) will take some effort to not attract attention. 

[Tony D]

Oh, by 'cam come on' I mean you are going what you think is gangbusters making all the good noises and suddenly as you cross 4,000 (or in our Bonneville 2 Liter, 6,500) the back end gets squirrely as the wheels start slipping as the power REALLY starts being put out in earnest.

 

our driver in the 2 liter said "yeah, I thought this isn't anything...until that thing hit 6,500, then it was like 'holy hell this thing is pulling harder than my L28 on a 75 Nitrous Shot!' and the back end is all over the place and the next thing I know the shift light (9,500) is flashing and I shift, and it starts all over but since it only dropped 1,000 rpms it's just pulling harder!"

 

Like That...

[Xnke]

And people look at me funny when I tell them life is too short not to run a solid-roller cam...

 

(I've made it work, Tony!)

[Nate SERE]

Pulled the head today. Definitely blew the head gasket and did some damage to the piston. Doesn't seem to be any scoring to the cylinder.

[Xnke]

Detonation. Pull the pistons and check for broken rings.

 

Bore/stroke measurements?