Page0100's 383 Build

[page0100]

I started a thread about a crossram for this engine but I decided too expensive and not worth it for what I am hoping to achieve

This is the first engine I have ever built. I have no training aside from shop class in high school and my dad who used to be an auto shop teacher. I do however have a book that tells me how to do all this so here I go

I am told the block is from a 70 roadrunner, just got it back from shop bored .030 cam bearing and freeze plugs installed
Heads are 452s with some work done to them, 87cc, I do not know what they flow
Crank is standard stroke and has been ground
Pistons- I am going to order some keith black domed pistons.
Roller Cam- probably a comp- no idea on this part, what do you guys recommend
Roller Lifters, Rockers, new push rods etc
Edelbrock performer RPM intake
Quickfuel 750 carb
Headers.

Hoping for torque and HP around 425

I have all the bearings, will get the crank in today and hopefully a completed long block by the end of October

What do you guys think.

I do not know what I am going to put it in yet. I have a 70 sport satellite with a 440 already. Looking for a 68-70 charger

 

[Banzaiii67]

The heads look nice, brand new valves! Do you know which one the used ?

Did you have your block decked?

 

[page0100]

The heads look nice, brand new valves! Do you know which one the used ?

Did you have your block decked?

No idea on the valves, shop called flow tech in Orange County did them but I never got the paperwork

Block was not decked, machine shop said it was not needed

 

[Meep-Meep]

Forget the roller cam. Those heads are only good for about .520" lift without major port work so I'd just run the MP .528" / 284 mechanical. Also put the recommended dual springs and use a good high strength rocker arm like the Isky or Crane iron with 3/8" push rods. Or by now you can probably get a steel roller tip for the same money. The key is to have a stable valve train with the higher rate springs. Compression should be about 10.0:1 and hopefully you can get that without too big of a piston dome. I don't have the 383 compression math in my head so not sure the cc required. Single plane intake or maybe performer RPM with a 750 Vac secondary for all out HP or about 670 CFM for more street driving. 1 7/8" headers are a must. This combo should put your 4000 lb B body into the high 12's with slicks and deep gears (4.30 or maybe 4.56).

 

[page0100]

Forget the roller cam. Those heads are only good for about .520" lift without major port work so I'd just run the MP .528" / 284 mechanical. Also put the recommended dual springs and use a good high strength rocker arm like the Isky or Crane iron with 3/8" push rods. Or by now you can probably get a steel roller tip for the same money. The key is to have a stable valve train with the higher rate springs. Compression should be about 10.0:1 and hopefully you can get that without too big of a piston dome. I don't have the 383 compression math in my head so not sure the cc required. Single plane intake or maybe performer RPM with a 750 Vac secondary for all out HP or about 670 CFM for more street driving. 1 7/8" headers are a must. This combo should put your 4000 lb B body into the high 12's with slicks and deep gears (4.30 or maybe 4.56).

Found the cam- Jegs has it for 200 bucks with the lifters, I found some stock length 3/8 rods from COMP
Still looking for the rockers, I can't go roller rockers with that cam right?
Also I have springs (single) on the heads right now but know nothing about them- What dual springs should I get?

Car will most likely have an auto trans (high stall converter) and 3.91 gears, sure grip with some 9.5 inch wide wheels with a good chunk of rubber, 99% street driving, but I will take it to the strip at least once

 

[mopar 3 B]

Also forget the domed pistons. 10:1 forged flat tops will give you clearance for the .520 lift cam if timed right. Use valve springs set to height as recommended by cam manufacturer and yes you can use roller rockers minnum would be chrome shafts with any performance cam. Would recommend fully radius main bearings and high volume oil pump just do not plan using anything less than a 100 psi oil gauge. This engine likes oil and plenty of it would recommend a 6 quart oil pan with proper pickup tube no need to go with 1/2" tube the 3/8" will work fine. Have not destroyed a 383 since go to this type system even at sustained 6000 rpm runs.

 

[Meep-Meep]

X2 above except you may have to cut a valve relief for the intake only if using the .528" cam. I did with zero deck flat tops so be aware of that. MP has the correct springs but you can get from just about anywhere. Seat pressure will probably be about 130-140 at the stock installed height. Also you may have to have the spring seat cut to accept the inner spring.

 

[page0100]

Ok lots of information coming in. At .030 over and having 87cc chambers with no decking done and a compressed gasket thickness of .051 all the compression calculators are coming up in the 8.5 range with flat top pistons and 9.5 with the keith black dome pistons. Will flat tops be too low of a compression?

This is going to run on 91 octane and be a 99% street engine

I am good the with MP camshaft and lifter kit. (.528, 284)
I am good with the pushrods. (COMP 3/8 stock length)

I am still confused on the rockers and springs. meep-meep- can you tell me exactly which rockers and springs you would use for this build (part number or link) ?

I was thinking these springs

http://www.summitracing.com/parts/dcc-3412068/overview/

I have no clue on the rockers (shaft vs stud vs I have no idea)

- - - Updated - - -

Maybe the rockers from 440 source?

http://store.440source.com/Aluminum-Roller-Rockers_shafts-15-Ratio-New/productinfo/200-1045/

 

[dieseldazzle]

Ok lots of information coming in. At .030 over and having 87cc chambers with no decking done and a compressed gasket thickness of .051 all the compression calculators are coming up in the 8.5 range with flat top pistons and 9.5 with the keith black dome pistons. Will flat tops be too low of a compression?

This is going to run on 91 octane and be a 99% street engine

I am good the with MP camshaft and lifter kit. (.528, 284)
I am good with the pushrods. (COMP 3/8 stock length)

I am still confused on the rockers and springs. meep-meep- can you tell me exactly which rockers and springs you would use for this build (part number or link) ?

I was thinking these springs

http://www.summitracing.com/parts/dcc-3412068/overview/

I have no clue on the rockers (shaft vs stud vs I have no idea)

- - - Updated - - -

Maybe the rockers from 440 source?

http://store.440source.com/Aluminum-Roller-Rockers_shafts-15-Ratio-New/productinfo/200-1045/

My heads which where like yours used 1.80 installed height springs

The dcc link you put up is 1.680 installed i believe.

 

[Garys1969RR]

Both types of rocker arms, the stock stamped steel, or roller rockers, will mount on the rocker arm shaft, which is bolted to the head. I use the stock shaft with stamped steel rockers, stock pushrods, and a 509 cam. This works ok to about 5500 or 6000 RPM. Have experienced some valve float or valve train instability near 6000 RPM with this arrangement. Some ocaissional popping sounds during a high RPM burnout.

- - - Updated - - -

And as stated earlier, the chrome rocker arm shafts wear better and may be stronger.

- - - Updated - - -

Follow the cam manufacturers recommended valve spring pressures.

 

[mopar 3 B]

Sorry but I have no idea what cam I have other than flat tappet anti pump up lifters MP chrome shafts and stamped rockers. Engine ran fine before the crank bent and all other parts looked ok. Did improve oiling as per previous post added windage tray and fixed all other parts the professional engine builder messed up. Will run up to 6800 rpm with no problem and has been running for last 14 years think I have the combination right.

 

[Meep-Meep]

Here are the rockers I'm using on my 440 http://www.summitracing.com/parts/crn-64770-16 They are expensive but the Comp Magnum are even more than this. Good used Cranes or Isky's go for about $150.00. Do not run the stamped steel rockers and pencil like push rods with anything over stock spring pressures.

I just realized when you say KB dome you mean quench dome. This is a good call but keep in mind you may have to make clearance so the domes don't hit the head. You want closer to 10:1 CR with that cam. My 383 has 915 heads 79.5 CC (or less because they have been cut a couple of times) and zero deck flat top pistons. Head gasket I believe is a composition but can't recall. If you have a hard time getting there on compression try steel shim gasket (.020-.025" compressed) and cut the heads a bunch. But quench dome should do it.

 

[Banzaiii67]

I've learned the hard way with these 383. Off the shelf pistons for a 383 are all below deck.. All KB's Hyper Pistons on a 383 block are anywhere from .024-.030 down in the hole (1.908 CH), this is why I kept asking about your deck height. I've heard on a 1970-1971 383 block the are even worse and are sometime anywhere from .040-.060 in the hole.

With a quench dome piston and .051 gasket and open chamber heads you'll have ZERO quench.

Speed Pro make a forged piston flat top it's got a compression height of 1.920, it's the closest thing to a stock replacement but it's heavy and has no valve reliefs.

You could go to a custom piston, and have it made to 1.935 comp distance. The cost will be between $800-1000, and will require the use of aftermarket rods.

If the builder told you it's fine, and you have no proof that the deck height has been milled, than the builder probably doesn't understand that the aftermarket for a 383 piston isn't the same as it is for a 440. At least that was my case.

If you want to do this right and have anything up to or above 9:5.1 compression with good quench using a stock crank and rods and you will have to mill your deck height and mock this up with a piston, otherwise you'll have to do what i did. Closed Chambered (mine were 82.5cc) heads + steel shim head gaskets and i've only got 9.1:1 compression on mine.

What i'd do is get the KB162 pistons, mock it up and than decide how much you'll need to take off the deck and get it done at a machine shop, or just take the thing back with your pistons have them do the math.

 

[451Mopar]

Test fit a cam to make sure the cam bearings are sized right before assembling the engine.
If you use a Flat tappet can, I would recommend the lifter bore burnishing tool from Hughes Engines:
http://www.hughesengines.com/Index/...TGlmdGVyIEJ1cm5pc2hpbmcgQmFsbA==&partid=11372
Did you run a tap through all the holes in the block and wash the block out good?

The pushrods should be the last thing you get. You want to measure for the correct pushrod length with all the parts you will be using, and the way the engine is assembled. Decking the block or heads, Head gasket thickness, cam base circle, lifter height, rocker arms, they all need the be accounted for in the pushrod length.

I won't comment on a cam or piston choice at this time. The 383 is fairly easy to over cam, but a good hi-stall converter can help that issue.

 

[Meep-Meep]

With a quench dome piston and .051 gasket and open chamber heads you'll have ZERO quench.

This is not true. Zero quench would only be possible if the chamber was a consistent depth all the way around. Like an open tuna can over a flat top piston. The open chamber head still has an area that is closer to the piston on one side. The quench gap is larger than would be found on a closed chamber head but turbulence will still be produced in the chamber.

My thoughts on quench. It is not the end all be all in fighting detonation but does help. If you have too much compression for the available fuel, or poor fuel distribution that is causing even one cylinder to run lean, quench isn't going to fix it. Quench will help push the fuel vapor to the plug side and mix things up a bit and that ultimately makes for better efficiency out of that same amount of fuel. One must start with planning the build around the available fuel.

 

[page0100]

Well I was going to take the rods back to the machine shop to get them attached to the pistons that I order.

I was going to take the heads back when I decide on the springs to get them installed by the shop.



Date Code on the block is 5-6-68



With those 162 pistons (flat top) the compression calculator with 0 decking is coming out at 8.6, with the dome I am at 9.5.1 with zero on the decking in the calculator

I am going to order the dome pistons and then mock it up then I will use this with the dial gauge to figure out the decking

http://www.powerhouseproducts.com/ph/standard-3-hole-deck-bridgehtml/

I am afraid if I order the flat top pistons and have 87cc chambers I will never get the compression above 9.1.1 unless I take a ton off the deck


Cam- with the MP 528/284 cam am I going to have to constantly make adjustments for the lash? Is there an official spring recommendation from Mopar,
,
Still looking at rockers - has anyone used the 440 source rockers with a similar setup?

Appreciate all the advice


I chased all the holes with the tap today.

I think I will get the crank in tomorrow.

- - - Updated - - -

Well I was going to take the rods back to the machine shop to get them attached to the pistons that I order.

I was going to take the heads back when I decide on the springs to get them installed by the shop.



Date Code on the block is 5-6-68



With those 162 pistons (flat top) the compression calculator with 0 decking is coming out at 8.6, with the dome I am at 9.5.1 with zero on the decking in the calculator

I am going to order the dome pistons and then mock it up then I will use this with the dial gauge to figure out the decking

http://www.powerhouseproducts.com/ph/standard-3-hole-deck-bridgehtml/

I am afraid if I order the flat top pistons and have 87cc chambers I will never get the compression above 9.1.1 unless I take a ton off the deck


Cam- with the MP 528/284 cam: am I going to have to constantly make adjustments for the lash, or do I set it and then its good? Is there an official spring recommendation from Mopar,
,
Still looking at rockers - has anyone used the 440 source rockers with a similar setup?

Appreciate all the advice


I chased all the holes with the tap today.

I think I will get the crank in tomorrow.

 

[Meep-Meep]

You are doing the right thing by measuring. 8.6:1 is not enough for that cam so try to get as close to 10:1 as you can. You can mill the heads quite a bit to help you reach your goal but also you must mill the intake face. There is a formula that states how much to remove off the intake face per .***" off the deck. You can also go with a smaller hydraulic cam. It all depends on what you expect out of that engine.

 

[page0100]

I really want about 400-450 streetable horsepower as simple as possible

 

[70bigblockdodge]

Did you measure the head volume I have never seen a set of 452s have less than 90cc without being milled. I agree on waiting to order pushrods till last. I would just use a MP 292/509 cam or something similar in a hyd. unless you go back in and have some work done in the head, inner spring seats, bowl and gasket match. my 2 cents anyway

 

[Meep-Meep]

I really want about 400-450 streetable horsepower as simple as possible

I believe I was there with my 383. .528" cam. Flat tops pistons .005" in the hole. Pocket ported 915 heads with standard valves. Torker intake with Holley 750 vac secondary (3310-2). 1-7/8" headers and a 4.88 Dana. 68 RR went 12.65 @ 107 with slicks. The .528" is way more streetable than the .509"