383

[PaulO]

Bad news!!
I spent last weekend swapping my tired 260 Mercrusher for the new 383 long block from Doug's racing in Wash. Pain in the #$%^ with all the pieces you don't think about like the fuel pump push rod and oil cooler fittings/lines, etc. Anyway, get it in, starts right up in the driveway, adjust the timing, run it for a while like that to break in the cam. Drop the boat in the water and idle out. Sounds real good so far, you can actually hear the difference in the exhaust note even at idle. Although the builder stated that once the initial cam break in was done that there was no real break in anymore, I began applying power gingerly. All seemed well up until about 3200 RPM when I began to hear a whining noise. Shut it down, found nothing, tried again. All was well again up until 3200 RPM and the noise returned. Idled down and now had a bad clanging noise. After some inspection found that the brand new SFI approved, steel damper had come apart and seperated a welded-on ring off the back which was now flying around and hitting the timing cover and the timing pointer. Got towed back for the first time in 20 years!!!

Next day pulled off the damper, got a new one locally, replaced it and started it up. Now I have a horrible knocking and a small hole through the oil pan near the front of the motor!!!.

It appears that Doug's is bending over backwards and assembling another engine for me ASAP. Unfortunately, downtime will follow. That is the risk of a mid-season engine swap.

I will be pulling the engine out this week to satisfy my curiousity and at the urging of the gentleman from Doug's. They are concerned that if it was a balancer failure that caused the whole mess, that they need to be aware.

I am dissapointed but, this is part of boating. Will keep you informed.
PaulO

[GeneD]

PaulO,
Sorry to hear it big fella, but your last sentence sums it all up doesn't it?
Bummer...
Put the 250 back in and wait it out.

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GeneD
007
Melbourne, Florida

[seano]

Paul,

That sucks...but I was watching Trucks! on TNN(I love that show) and they mentioned that the 383's were growing in popularity and noted that many people who build them them selves(installing a 400 crank...) fail to install the correct harmonic balancer and flywheel...I know you got the motor from Doug's, but were those items included? Did you use the old flywheel, etc...

I could be way off course, but the show mentioned this and said the motor would come apart if one used a balance and flywheel form a stock 350.

[RickSE]

400 cranks are externally balanced meaning the rely on the balancer and flywheel/flexplate for balancing.

All other SBC's are internally balanced and these crankshafts can be balanced with out the balancer and flywheel.

Stock 400 balancers will have a large section of the outside diameter removed. I think 400 flywheels have holes drilled in them while the 400 flexplates have weights attached near the ring gear.

[PaulO]

Actually, the balancer was provided and installed by the builder and was correct for an externally balanced motor which this is. The flywheel I used was the stock 350 flywheel which was installed with the added plate which mounts under the flywheel to provide the external balance. This plate was provided by the builder also.

It is possible that an internal failure threw the engine out of balance resulting in the balancer failure but, I don't think so. I am hoping for some clues to present themselves upon dissassembly.
PaulO

[seano]

Cool,

Now I know some more about stroker motors... http://www.donzi.net/ubb/smile.gif See what tv will do to ya...make ya think yer an expert and all...

Thats great information...so, something may have let go internally, but that whining noise...??? Could it have been something wrong in the distibutor? Did the damper coming off do something to the timing? Or did a rod just let go?

Paul, I definitely don't know alot about this subject, so please excuse my ignorant questions...I'm very interested to hear the outcome and the cause of that motor coming apart.

[GEOO]

Paul O,
Engine's HUH!!! Mine has a electronic noise problem which causes the fuel injection to fire when the motor is turned off. Makes it very difficult to start. Sorry to hear of your troubles. GEOO

[Forrest]

Bummer PaulO. I too am very interested as to what put that hole in the oil pan. You may want to get Doug's to dyno test the replacement.

------------------
Forrest

[PaulO]

Geoo,
Now that is a first! How did you come to that conclusion? Do you know the source of the interference? Do you know how it is triggering the injectors to fire? I would imagine that it would need to be via the control unit since the injectors themselves must operate at too high a voltage. Where is the control unit and can it be sheilded?
PaulO

[RickSE]

I'd suggest buying a 400 flywheel and having the engine supplier balance the crank with the balancer and flywheel that will be installed. 400 flywheels are still available from GM, part #3986394. You may not have lost the engine due to balance but it's always a good idea to balance 400 cranks with the actual components going on the engine.

[GEOO]

PaulO,
The Distributor triggers the ECU. The wire from the ECU is shielded but the distributor wire and the connector is not. Most of the switching is controlled through grounding, ot positive wires. Somehow a negitive pulse is traveling to the ECU and then it sets off the injectors and since the ECU thinks the motor is running the fuel pump stays on. The ground were redone to a common ground and this helped, now the injectors fire only for a few extra times, enough to flood the engine but not hydro lock the motor as before. This SUCKS I'm dieing to get running. I though I picked the right ECU unit. I spoke to several EFI companies they all say trial and error will find the noise!! http://www.donzi.net/ubb/confused.gif GEOO

[rayjay]

GEOO, Too bad. Welcome to the wonderful world of modern electronics. Have you tried and "percussive" maintenance on it? You know, the delicate art of pounding the s*^# out of something electronic until it works correctly or the problem gets fixed (usually by having to buy a new one). Ballpeen hammers work exceptionally good for this!

I am a partner in a m/c dealership and race shop. Some of the new bikes we are preparing have f/i, so I am learning (too much) about the problems of electronic f/i first hand. rj

[Riley]

PaulO, sorry to hear about your misfortune with the 383. This brings up a question I have been mulling over with regards to engine displacement and the Alpha One drive unit: Why do so many guys rush to spend the extra money on building a 383 small block, when a 350 can be built far more economically, and still make enough power to rip the guts out of an Alpha One? I would think the extra money spent on a stroker crank and the various support parts would be much better spent on a 350 for improvements in cam, intake, and exhaust systems. Any thoughts on the subject?

[PaulO]

Riley,
Perhaps I am in denial but, I hope to avoid ripping the old Alpha to shreds. I think that it may be possible to preserve the Alpha through restraint while accelerating, a drive shower, and fanatical maintenance. I know several people locally who run Alphas behind warmed over big blocks successfully. If I am wrong,the Alpha to Alpha SS or Bravo one swap is not that difficult. As far as a 350 build-up as opposed to the 383, I feel that you would have to go a step or two more radical with the 350 to make up for the displacement difference which would mean more aggresive cam, higher comp. ratio, etc. that would take away from idle quality and low end grunt. Although, I may be proven wrong, I can't get myself to agree with the use of aftermarket hi-po exhaust. Besides the exhorbitant expense ( much more than stroker components) I can't believe that those large chambered exhaust manifolds, huge diameter risers, and straight, short shot through the transom of stock exhaust could be restrictive ( I know about seperating runners).
Just my opinions.
PaulO

[Riley]

PaulO, you make several good points. I am from the old school of "being no replacement for displacement". I tend to agree with you regarding aftermarket exhaust systems, as well. Regarding the old Alpha...I hope you are right! I plan on following in your footsteps over the winter, so I'm keeping a close eye on your progress. Keep up the good work!

[GeneD]

PaulO,
Good one! Very well said.
As for the after market exhaust, those things are tuned for a torque curve. I agree with you on this issue. Basically, we are either wide open or something similar. So we really don't require tuned exhaust. Would be nice, but do we REALLY need it?
I can not justify the expense.

------------------
GeneD
007
Melbourne, Florida

[RichF]

PaulO:
BUMMER!! Sorry to hear about your stroker problems. I know from experience, the boat still looks good being towed!! (just kidding) Man, that Donzi went through a lot of changes in the past year, huh? I hope everything works out ok!

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Rich mailto:fngrht@aol.comfngrht@aol.com</A>
http://www.corvetteforum.net/classics/richf/wave.gif

[This message has been edited by RichF (edited 08-02-2000).]

[Riley]

PaulO, I'm curious as to what type of money you have into your 383 engine....I've spent a lot of time on Jim Pace's crate motor web site (www.paceparts.com), and they have an interesting 383 listed there. The engine lists for $2679.95, and includes a forged crank, powder metal rods, hypereutectic pistons, vortec heads, truck roller cam, and an aluminum dual plane intake manifold, and 4 bolt mains. Although it only puts out 325 hp at 4500 rpm, the thing cranks out over 400 lbs/ft of torque between 2500 and 4000 rpm! Oh, it also runs on 87 octane. I would think bigger horsepower numbers would be a cam swap away, but with those torque numbers I would think you could swing a monster prop and still have the engine live forever. Any thoughts on an engine like this, and do you think the price is reasonable?

[PaulO]

Riley,
I had looked into that crate motor and think it is a great deal. The only problem is that there are production delays and it is not available. Estimates are not until the end of the year. There would have to be certain changes made to that engine to "marinize" it that you probably couldn't order from GM such as marine gaskets and brass plugs. You would have to dissasemble to do that and then there are questions with comp. ratio and quench since you would probably change the gasket thickness. Pros and cons, you get the roller setup but you also need to figure out what to do with the flywheel and coupler since it is a late style one piece main crank. You don't have your choice of cams so, you will most likely need to swap the cam. Don't know if there is a windage tray in the oil pan so......

Anyway, since it wasn't available I didn't have to debate.

The engine I got was $2,800.00 and they pay half of the shipping. It includes WorldProducts cast iron heads( either S/R torquers or Sportsmans) forged crank, some after market rods I can't recall, hypereutectic pistons, oil pan with welded in windage tray, marine gaskets, balancer (oops), and all the other expected stuff.

PaulO

[Riley]

PaulO, Hey, by now you must be sick of hearing from this Riley guy! Seriously, I am a little in the dark as to what you were reffering to as a " one piece main crank". Will this bolt up to my 1999 Alpha One? I plan on pulling most of the marine gear off of my 305, including the oil pan, if necessary. I don't have any problem with changing the head gaskets or the freeze plugs, either. I'm still curious as to what you guys think about a high-torque, low rpm small block attatched to the Alpha one. Is it torque or high-rpm that kills outdrives? Thanks again for all of your information, the people on this website are a great group!

[GEOO]

Riley,
I think an Alpha can handle the higher torque and hp in a 18 foot boat. The drives run into most of the problems when there is a heavy strain, ie heavy larger boat, fast holeshots (waterskiing), staying on the thottle after being airborne. Here is an article from Hot Boat on the Phython Viper 18. It is a Donzi 18 2+3 knock off; ran 82+ mph with a 500hp 400ci small block.
http://free.hotboat.net/tests/docs/Python_18_Vyper.htm
I talked to the owner/manufacturer. He said they had the drive last along time. It finally died when they put the 500hp small block into a 24' Phython and added a Procharger. They ran an Alpha SS. I don't think the SS model is rated for more hp it is just shorter. (Gene would know) GEOO

[This message has been edited by GEOO (edited 08-03-2000).]

[PaulO]

Riley,
I was reffering to the newer style ( since 86 I think) one piece rear main seal. The crank is different and the bolt pattern for flywheels/couplers is different. Just something to consider. And, I am not sick of hearing from you!!!
PaulO

[GeneD]

According to the Lake X guys, and my personal observations the last time the SS grenaded, the Alpha SS is a beefier version of the Alpha One. The gears are bigger and the bearings are definitely bigger. Not too sure about the shaft though. It seemed as if the gears were wider, the bearings just bigger all around.
And since the primo rebuild, (as opposed to the budget rebuild just prior to the primo rebuild) I haven't experienced one bad moment with the thing. And anyone that has ever driven with me in the Donzi knows I do not spare the throttle.
As things would happen, I just talked to a guy that says he can get 2 Alpha SS's. Anyone interested?
Email me, or post so that I can get a feel for who really wants/needs one. No auctions, okay?
Don't know the price yet.

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GeneD
007
Melbourne, Florida

[This message has been edited by GeneD (edited 08-04-2000).]

[This message has been edited by GeneD (edited 08-04-2000).]

[PaulO]

Geoo,
Entertaining article. I don't get this though:

Python is not beyond offering family boats that are somewhat more sedate in nature. The base Vyper, in fact, is rigged with a crate-stock version of MerCruiser’s 5.7L Chevy small-block/Alpha package, a source of power that Python says is sufficient to motivate a 90-mph performance. It also produces a couple of 21-footers and a 24-foot vee.

90?

PaulO

[RickR]

That must be a real trick Small Block to be able to develop 500hp@4950RPM

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RICKR
mailto:riggerb@aol.comriggerb@aol.com</A>

[GEOO]

Rick,R,
The numbers(pitch, gear & rpm's) didn't work out at 4950 rpm's. I asked about the rpm's. He said it revs closer to 6000.
PaulO,
I didn't understand the bit about the small block doing 90??; unless he is talking about putting it in a small Hydro.

I might be heading out to Toledo, Ohio, Saturday with my boat, to pick up, install, and possibly a test drive my new package. Anyone in the Toledo area. GEOO

[This message has been edited by GEOO (edited 08-04-2000).]

[This message has been edited by GEOO (edited 08-04-2000).]