Building a 383 Stroker

[Scott Danforth]

Re: Building a 383 Stroker

I would go with a comp cams marine bump stick on the cam. however like many stated, talk to your machine shop. find one that does marine engines often.

 

[greg82255]

Re: Building a 383 Stroker

Thanks again for all the input. I have a few more questions. Still haven't gotten a quote yet, but I fear that it's going to be far more than the price of just buying a long block from some place like US Engines or Michigan Motorz. I've been looking around and have seen complete rotating assembly kits that claim they are already balanced, such as this one from Summit (and they also sell a reman '96-'00, roller cam compatible block for $650:

http://www.summitracing.com/parts/ESP-B13004L03053/?rtype=10
http://www.summitracing.com/parts/SUM-150100/

Would a combination like this work with a neutral flywheel and harmonic balancer? I'd obviously have to get a kit that will give me the right CR, but I am more asking about balancing here.

Bondo - I'm not sure what you mean by .043" piston quench. Could you explain that? This is my first time building an engine but I'm determined to do it myself and not buy something pre-assembled..

As for the exhaust, I was planning on going with the stock manifolds, but maybe buying a set of risers like these:
http://www.cpperformance.com/p-1341...al-mercury-manifolds-standard-dimensions.aspx
They claim to be more free-flowing and add ~10hp.

 

[RogersJetboat454]

Re: Building a 383 Stroker

Thanks again for all the input. I have a few more questions. Still haven't gotten a quote yet, but I fear that it's going to be far more than the price of just buying a long block from some place like US Engines or Michigan Motorz. I've been looking around and have seen complete rotating assembly kits that claim they are already balanced, such as this one from Summit (and they also sell a reman '96-'00, roller cam compatible block for $650:

http://www.summitracing.com/parts/ESP-B13004L03053/?rtype=10
http://www.summitracing.com/parts/SUM-150100/

Would a combination like this work with a neutral flywheel and harmonic balancer? I'd obviously have to get a kit that will give me the right CR, but I am more asking about balancing here.

Bondo - I'm not sure what you mean by .043" piston quench. Could you explain that? This is my first time building an engine but I'm determined to do it myself and not buy something pre-assembled..

As for the exhaust, I was planning on going with the stock manifolds, but maybe buying a set of risers like these:
http://www.cpperformance.com/p-1341...al-mercury-manifolds-standard-dimensions.aspx
They claim to be more free-flowing and add ~10hp.

The kit you showed is externally balanced. You would need an externally balanced flywheel and balancer to match.

Decent article on quench... saves me from typing...
http://www.chevyhiperformance.com/techarticles/94138_piston_head_clearance_guide/index.html

 

[greg82255]

Re: Building a 383 Stroker

You're right - It is externally balanced, I missed that in the specs. I just picked that one as an example - they also sell kits that come with a balancer and flywheel. I guess I'll wait for the quote from the machine shop before I decide what makes the most sense. Hopefully he will get back to me today.

 

[RogersJetboat454]

Re: Building a 383 Stroker

You're right - It is externally balanced, I missed that in the specs. I just picked that one as an example - they also sell kits that come with a balancer and flywheel. I guess I'll wait for the quote from the machine shop before I decide what makes the most sense. Hopefully he will get back to me today.

The ship may have sailed on this idea, but it probably would have been better if you made the drive and sat down with him (rather than playing phone tag).

When I did my engine with him, I brought my block, rods, pistons, and bearings to him. We sat down at his computer and figured it all out right then and there. He had a standard 350 crank all ready cut, so it was just an even exchange with my good core (obviously not the case with you). I bought a set of reconditioned pink rods through JCWhitney (big mistake), he showed me a huge wire basket full of PM core rods ready for machining. I used ARP studs for my 2 bolt mains, and ARP wave-loc's for my rods. My piston's were .030 KB Hypereutectic Silv-o-lites, that he had no problems installing and balancing on the rods. I purchased the flex plate and Performer RPM heads through him, and all said and done walked out the door with machine work and parts for about 2K.

This all happened about 8-9 years ago, but I remember he was a reasonable guy to work with. May be still worth it to see him, sit down, and state your intentions, a HP target range, and a price target range without sacrificing reliability.

 

[Bondo]

Re: Building a 383 Stroker

Bondo - I'm not sure what you mean by .043" piston quench. Could you explain that? This is my first time building an engine but I'm determined to do it myself and not buy something pre-assembled..

Ayuh,... RJB's link is a pretty good write up, 'n explains it nicely...

You'll need D-dished pistons to keep the comp ratio down to a livable level, even though the Vortecs help in the detonation dept...

 

[greg82255]

Re: Building a 383 Stroker

I am definitely open to going up there and sitting down with him once I get some free time. Once I get his quote, if it's too much then I'll be straight with him. I'll tell him I'm on a strict budget and if I can't get close to that budget then the project isn't going to happen. He seemed very reasonable on the phone so I doubt there will be any problems. He knows he's going to make some $ if he does this project so that should be an incentive to get closer to my budget.

 

[mhouse40]

Re: Building a 383 Stroker

Well on the bright side of it here, I am sure if he doesnt want to work out a deal or tries stickin ya on it, there are others out there whom could use the work. Its been a very long time since I have dealt with a machine shop, but i got lucky by knowing the owners daughter, which got me good service . He is still in buisness today and runs dependable machine service in overland MO. I would think that with times being tuff all around that he would do his best to satisfy his customers??? Keep us posted !

 

[greg82255]

Re: Building a 383 Stroker

Alright here's the quote he gave me, including parts and labor:

Block Work:
-Oven Clean, Blast and Mag Block $100
-Bore and Hone block with torque plate $350
-Line Hone Main Line $175
-Zero Deck Block $150
-Clearance block for 383 $75
-Install cam bearings and brass freeze plugs $100 (includes bearings and plugs)

Total for block work: $950. I can buy a block from Summit with all the above work done for $651 + $149 shipping to my door.

-Balance Rotating Assembly $350
-Scat Cast Steel 383 Stroker Crankshaft $325
-Scat 4340 forged steel I-Beam rods with ARP rod bolts $250
-Mahle Forged piston and ring kit $600
-Clevite H-Series Main and rod bearings $125

Total: $1650. The same crankshaft is on Summit for 250. Haven't checked out the other parts yet. Plus someone in an above post said that the Mercury 383 uses Hypereutectic pistons so forged are unnecessary.

He says he recommends finding a set of GM Cast Iron Vortec heads in order to reach the hp goal.
Head work:
-Three Angle performance valve job $225
-Resurface heads $150
-Final assemble and set installed heights $75 (includes Viton valve seals and shims)
-Manley Stainless Steel Valves $150

Total for heads: $600 NOT including the cost of used heads. I can buy a brand new set of Vortec heads for $330 each...

Total for all his work comes out to $2600 not including heads, $3200 including head work. I can go to US Engines and buy a 383 long block already assembled for $2695 (350 hp) or $3295 (400 hp).

This also does not include a camshaft or lifter kit.

Assuming I can get him to match the $800 for block work (same price as summit's block), what else could I potentially do here to get the price down to my goal of 2k (I'll buy new heads outside of the 2k budget)?

 

[sschefer]

Re: Building a 383 Stroker

Hopefully your not just looking for HP gains and forgetting about Torque gains. That's the number you really want to pay attention to and they don't necessarily pair up.

 

[greg82255]

Re: Building a 383 Stroker

Hopefully your not just looking for HP gains and forgetting about Torque gains. That's the number you really want to pay attention to and they don't necessarily pair up.

I assume the camshaft selection will have a lot to do with that? Once I get going I'll definitely be looking for help selecting one.

 

[sschefer]

Re: Building a 383 Stroker

I assume the camshaft selection will have a lot to do with that? Once I get going I'll definitely be looking for help selecting one.

The camshaft definitely plays a big role but the heads, crank shaft and compression ratio are all critical players. If you ever wondered why GM uses the truck engines in most of their marine applications this is why. You need to stretch out the power curve by sustaining the hp with torque. That's not what you want in a car but it is what you want in a truck or boat.

 

[RogersJetboat454]

Re: Building a 383 Stroker

Alright here's the quote he gave me, including parts and labor:

Block Work:
-Oven Clean, Blast and Mag Block $100
-Bore and Hone block with torque plate $350
-Line Hone Main Line $175
-Zero Deck Block $150
-Clearance block for 383 $75
-Install cam bearings and brass freeze plugs $100 (includes bearings and plugs)

Total for block work: $950. I can buy a block from Summit with all the above work done for $651 + $149 shipping to my door.

-Balance Rotating Assembly $350
-Scat Cast Steel 383 Stroker Crankshaft $325
-Scat 4340 forged steel I-Beam rods with ARP rod bolts $250
-Mahle Forged piston and ring kit $600
-Clevite H-Series Main and rod bearings $125

Total: $1650. The same crankshaft is on Summit for 250. Haven't checked out the other parts yet. Plus someone in an above post said that the Mercury 383 uses Hypereutectic pistons so forged are unnecessary.

He says he recommends finding a set of GM Cast Iron Vortec heads in order to reach the hp goal.
Head work:
-Three Angle performance valve job $225
-Resurface heads $150
-Final assemble and set installed heights $75 (includes Viton valve seals and shims)
-Manley Stainless Steel Valves $150

Total for heads: $600 NOT including the cost of used heads. I can buy a brand new set of Vortec heads for $330 each...

Total for all his work comes out to $2600 not including heads, $3200 including head work. I can go to US Engines and buy a 383 long block already assembled for $2695 (350 hp) or $3295 (400 hp).

This also does not include a camshaft or lifter kit.

Assuming I can get him to match the $800 for block work (same price as summit's block), what else could I potentially do here to get the price down to my goal of 2k (I'll buy new heads outside of the 2k budget)?

Well, there is some wiggle room with the choice of rods.
You could probably get away with reconditioning your rods, and using ARP rod bolts. Although the cost of both would be pretty close to what he quoted you for the better rods with the ARP hardware included. I'm also fairly confident that you could use Hypereutectic pistons without issue. Find a set that suits your needs, and go from there. You could buy your own crank to give to him too. It's up to you with the heads. Either buy the new castings, or like I told you before, I can check with a friend to see if he has a set that you could use as rebuildable cores.

The cost of a mil from US engines is attractive, and they probably build a decent product. But I also know from experience this guy does top notch machine work. I don't know if he still offers it, but when I had my engine done through him, he offered a lifetime warranty with his machine work. If anything he did caused a failure, he would fix it for no charge. If a part broke, you were responsible for the cost of the part, but he would take care of the machine work to make it right. When he did the 383's for my buddy's Century, one ended up having a problem with head gasket sealing. He took it back, and made it right for no charge.

At least you have some time to ponder your options.

 

[greg82255]

Re: Building a 383 Stroker

The camshaft definitely plays a big role but the heads, crank shaft and compression ratio are all critical players. If you ever wondered why GM uses the truck engines in most of their marine applications this is why. You need to stretch out the power curve by sustaining the hp with torque. That's not what you want in a car but it is what you want in a truck or boat.

Agreed. I am shooting for somewhere between 9 and 9.5:1. Definitely taking CR into consideration when selecting the pistons and heads.. I assume the vortec heads have 64cc chambers?

The cost of a mil from US engines is attractive, and they probably build a decent product. But I also know from experience this guy does top notch machine work. I don't know if he still offers it, but when I had my engine done through him, he offered a lifetime warranty with his machine work. If anything he did caused a failure, he would fix it for no charge. If a part broke, you were responsible for the cost of the part, but he would take care of the machine work to make it right. When he did the 383's for my buddy's Century, one ended up having a problem with head gasket sealing. He took it back, and made it right for no charge.

Ideally I'd like to keep my block, have it machined and do all the assembly myself. If this guy is really good then I'd rather have him do it. He's local and will stand behind his work, which is much better than having to deal with a company some number of miles away that would take weeks to solve a problem. As for those vortec heads - he wanted $600 to recondition a used set, plus the cost of buying the cores. There are new/remanufactured sets of GM vortec heads all over ebay and other sites for right around $600 a pair. I have a while to think about that though. I'll definitely let you know if I choose to get a used set.

On another note, I keep looking for a set of pistons that will give me the right CR. Assuming I have a 3.75" stroke, 5.7" rods, and 64cc vortec heads, can someone post the size of dish pistons I'm looking for? I see them anywhere from +5.0cc up to +18cc. What will work, and what else goes into it?

 

[mhouse40]

Re: Building a 383 Stroker

Thanks for the update Greg! I too was a little suspicious about it but wasnt 100& sure as for who i was looking into buying my engine from ( US ENGINE).They claim they have a BBB rating of A+ but upon looking them up, it said they dont report to the BBB??? (my coworker explained it all to me) anyways waiting to see the responses about your piston size's.

 

[greg82255]

Re: Building a 383 Stroker

Thanks for the update Greg! I too was a little suspicious about it but wasnt 100& sure as for who i was looking into buying my engine from ( US ENGINE).They claim they have a BBB rating of A+ but upon looking them up, it said they dont report to the BBB??? (my coworker explained it all to me) anyways waiting to see the responses about your piston size's.

The machine shop I'm working with is bringing its price down for me. They have already knocked off a few hundred $$ and I am almost to the point where I am going to go ahead and do it. I'll post all the parts and part #s as soon as I get a complete list of what I'm going to use.

 

[RogersJetboat454]

Re: Building a 383 Stroker

On another note, I keep looking for a set of pistons that will give me the right CR. Assuming I have a 3.75" stroke, 5.7" rods, and 64cc vortec heads, can someone post the size of dish pistons I'm looking for? I see them anywhere from +5.0cc up to +18cc. What will work, and what else goes into it?

Greg,
With your small chambered head, and zero deck height, you are gunna want dished pistons to keep your CR reasonable. When I plug everything into Summit, this is what I get for options;
http://www.summitracing.com/search/...tyle/Dish-with-two-valve-reliefs/?Ns=Rank|Asc

Another factor that will determine the CR is the compressed thickness of the head gasket. If Chad gave you the PN of the head gaskets he's going to use, look up the PN's at summit to find the compressed thickness. Summit offers a CR calculator that you can fool around with entering the different spec's of the pistons offered.; http://www.summitracing.com/expertadvice/popup.aspx?Control=CompressionCalculator

 

[greg82255]

Re: Building a 383 Stroker

Thanks for the link. I used the CR calculator and entered in 4.030" bore, 3.75" stroke, 64cc chambers, +18.0cc dish pistons. 0 deck height, and .051" compressed head gasket thickness and got a CR of 9.45:1. Using .061" for the thickness, it drops to 9.26:1, and with .071" it drops to 9.09:1. Using the +12.00cc pistons and .071" gasket thickness, I get 9.63:1, which I think is higher than I want to go.

Chad recommended that I stay close to 9:1, and said that I could use any high performance head gasket with a stainless core, didn't give any part #s. What advantage/disadvantages are there running 9.5:1 as opposed to 9:1? 87 octane vs 89? anything else?

 

[John_S]

Re: Building a 383 Stroker

While it is typical to see 350/vortec compression ratios at 9.4 to 1, most strokers, with or without vortecs, are like what your machinist said, 9 to 1. Even Merc Black Scorpion (350hp @ prop) is 9 to 1, and 92 octane is recommended. With a very tight budget build, I'd stay with the norm.

 

[Bondo]

Re: Building a 383 Stroker

Ayuh,... Ya also have to take into consideration that the Vortec design heads are Much more detonation tolerant...

For what yer guy wants for rebuilt iron vortecs, ya can almost buy a set of aluminum vortecs...
With aluminum vortecs, I'd go with the 18cc dished pistons, 'n a head gasket closer to .043"...