Building a TBI 350.

I have an L05 on the stand out of an '87 1/2 ton. It was smoking, needs
to be honed, needs rings. Heads need to be cleaned up, valve seals, etc.
Balancer is spun, few other things. I checked the main bearings, and they are all good. To get it functional I figure:

Rings $40.00
Rod bearings $40.00
Valve seals $20.00
Harmonic balancer $50.00
Pushrods $20.00
Cleanup 193 heads $75
Rear main seal $20

$265 total

Or, I was offered a 'Goodwrench 350' which hs 8.5:1, has the 93417369 heads (76cc), 4bolt main block but 2pc rear seal. These motors are rated at 260 hp, and 300 foot lbs with a quadrajet carb. The motor comes with an aluminum dual plain intake manifold. The oil pan is crap, and the rear main seal leaks. So I figure:

Motor itself $300.00
Carb adapter $25.00
Oil Pan $40.00
Rear main seal $15.00
Valve seals $20.00

$400 total


What would YOU do ? This is a budget deal for a truck.

-- Joe

 

You'll at a bare minimum have to get the first combo honed at a shop if there isnt' a ridge already worn in the cylinder. You can do a quick ball hone in a drill, but those never last more than a few thousand miles before the smoke comes back. Also if the valve seals are bad more than likely the guides need replaced, that will add another 200$ or so to the build. On top of that it has the swirl port heads, which aren't all that bad but with the other option of the GM crate I would lean that way.

It may seem like more money for the crate motor, but in the long run you'll get many many more miles out of it than you will on a quicky rebuild on the LO5.

 

It's got a pretty serious ridge in it. I just looked at it for like an hour. I don't know what I want to do. I was gonna try to ream it, and then use the berry-hone on the cyls.

On another note. I don't get how the goodwrench has soo much more Hp than the l05. the cam is smaller, and it's less compression. Anyone have any insight on that?

-- Joe

 

If the goodwrench is in good shape, Id go for that. It sounds like there is alot of wear in the cylinders on the L05, they're likely past their service limit and would need to be overbored.
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Its not. Those are more like gross HP numbers. When I put it in the car, it was barely faster then the L03 it replaced.

 

Barely? Hrmm. Is it gonna be a pig compared to the L05 that was in the truck?

Thanks

-- Joe

 

It'll probably be comprable to the L05. A cam swap wouldnt hurt, unless you want maximum low end torque with the '929 thats in there. Edelbrock, Isky, Crane, etc make mild profile flat tappets that would provide good off-idle torque and a little more power out top. The Isky262, Summit 1102, or the performer plus would be a good match to the stock heads and have stock type profiles that wont overwhelm the springs.

 

Ok. So maybe the 1102 cam + lifter kit. It's cheap.

Is 929 the cam thats in there right now?

Am I to assume, the '369 heads that are on the goodwrench motor flow better than the '193 heads on the L05, and that the only 'downfall' is the large chambers?

Thanks!

-- Joe

 

If the cam in the smoking 350 is good and acceptable grind, you might think about putting that in the Goodwrench 350. Minimum cost would be a cam/lifter/pushrod swap engine to engine.
Or swap cam and get new lifters.

 

The 929 cam is the generic stock 350 camshaft, which even the TBI engine uses. The 369 heads do not flow much better than the 193s on the intake and even worse on the exhaust. The goodwrench engine I checked was more like 7.8:1 compression! The L05 is right at 9.3-9.4:1 compression. In my experience a stock L05 will pull harder than a stock LS9 350 as it should. The top HP for a stock LS9 was around 175 HP/275 TQ. The top power out-put for a 350 TBI was 215 HP/310 TQ

 

It's the stock L05 cam is:

248/252* @ .008, .382/.401 lift, 109* lobe seperation, installed on a 112*

The goodwrench 350 is:

195/202 @ .050 .383 /.401 in on 112* lobe sep

Which is probably to say, they are the same cam.

So the question is, do the 76cc '369 heads flow better than the 64cc '193s, and if so is it worth the compression loss? hrmm.

-- Joe

 

The L05 is a 112* LSA installed on a 108* ICL, duration numbers at .008" sound very close. I guess the biggest indicator is that both camshafts cross to the latest number which is used in both current crate engines.

 

So block blocks probably have the same dish pistons, the '929 heads flow worse on the exhaust side, so perhaps it would be better to clean up the intake ports on the '193 heads.

A Summit K1102 cam would probably work well with the 64cc '193 heads.

So it's either hone/re-ring the L05 block and get the 1pc rear main seal, or spring $300 for the Goodwrench block, hope the shortblock is good (cyls are better than the 1987 block? Date of the goodwrench is 1991) for a 4bolt main.

Either way it sounds like the '193 are better heads and net better compression ratio and those should be used. ?

hrmm..

-- Joe

 

I settled on the 193 heads. Infact, I went to the head shop and traded my '624s, and '193s + $145 for a set or rebuilt 193s.

From the builder:

"HEADS HAVE BEEN CLEANED(HOT TANKED THEN STEEL SHOTED TO LOOK LIKE NEW) MAGNAFLUXED TO CHECK FOR CRACKS,SEATS CUT 3 ANGLE,GUIDES CHECKED AND WELL WITHIN SPEC, VALVES BACKCUT 30 DEG TO IMPROVE FLOW,NEW MANLEY INTAKE VALVES,NEW SPRINGS,NEW SEALS (POSITIVE ON INTAKE UMBRELLA ON EXHAUST) RESURFACED ON MY VAN NORMAN 570 RESURFACER."

Should be good with the K1102 cam. Now I just need to figure the block part out.

-- Joe