Getting horsepower from a '71 383

[Fury Boy]

I have bought a junk yard 383 ( out of '71 Newport; 2 barrel carb)and i wont be rebuilding the motor. Compression is at 140 to 150 in all the cylinders. I'm stuffing the motor in a '63 Fury(stripped down drag car). Current mods will be an Edelbrock Torker manifold, Predator carb, Comp 280H cam(230 degrees at .050 and 480/491 lift), a mopar windage tray and I plan on using a two inch open spacer to gain some top end. For cooling i want to use a Mr. Gastet electric water pump driv kit. Exhaust is going through 1 3/4 headers and Cherry Bomb glass packs. Ignition is stock(single point) right now. My questions:
Will the ignition be okay? Will compression be high enough? Would there be any advantage of an electric fuel pump and if there is what one should i use? Will the electric drive kit have any advantage? I'm trying to get all the cheap horse power I can.

[Christopher]

You'll need a oil pan from a 62-65 car as the pan on your 383 won't fit the 63 chassis.You need the electronic ign kit.Compression will be fine,and depending on the chassis setup(converter gearing etc.)is where the rest of the pieces fall in at.The Holley pumps work good and the water pump drive is free horsepower.Forget the glasspacks though,they rob power.Use some type of aftermarket muffler,like Flowmaster.

[Fury Boy]

Thanks for the reply, Christopher

[451Mopar]

The 1971 383 engines came with 8.7:1 compression as advertised.
Your 140/150 pressure sounds pretty good, are you sure this is a stock 1971 engine?

The 1968-1970 engines had much higher compression ratios.

The rest looks ok, so here is my $0.02:
Use Dynomax Race Magnum mufflers, not the cheery bombs.
Check the piston to valve clearance with the new cam.
You will also need matching valve springs for the cam.
The single point ignition will probbly cause more problems than it is worth. Convert to electronic ignition. On the cheap, just buy the MP Chrome box and get the distrubitor and wiring from a junked car or truck, then recurve the distrubitor and use lighter advance springs.
Don't use the thick fel-pro head gaskets or you will lower the compression ratio even more. If you want you can mill the heads for more compression.
Check the lifter pre-load, expecially if you mill the heads. A cheap fix is to use big block Ford pushrods which are about 0.030" shorter than the 383 pushrods.
If using an automatic transmission, use a 10" or smaller converter with at least 3,000 RPM stall.

[Fury Boy]

I am pretty sure it's stock, because the two
barrel manifold and original exhaust manifols are still on. The motor has #346 heads and original blue valve covers are on the motor. I got it from a pick and pull '71
Newport. thanks for the advice.

[Chargerchuck]

What's your rear axle ratio? I would go with the 3000 stall converter but you need at least a 3:91 ratio. I did not notice, but maybe I missed it, make sure you run a trans cooler- you will fry your trans without a good unit. I would definitely go with a nice set of headers to wake things up a bit.

[Fury Boy]

Few more questions:

#1. Fel-pro head gaskest- 0.039" compressed
Mr.Gasket(steel head gaskets) .018-.020"comp.
what were the originals when compressed?
I would mill the heads but my Dad thinks we should leave them alone. if I have plenty of compression for my engine I don't want to do any machine work.
#2 has any one used the "Torque Plus" intake manifold gaskets? they look neat!
#3. The valve springs I am thinking about using are the Comp springs for valve lift up to .490" lift. Will these work better than stock spings?
#3. What lifters?
#4. I have looked at header wrap. is it worth it? for $35 a roll(and you need two rolls) it seems pretty expensive.

[This message has been edited by Fury Boy (edited November 17, 2000).]

[Fury Boy]

Plan on using a 4.10 or lower gears( maybe 4.56) in an 8 3/4 rear with a Strange spool. I can get a once used 4000 rpm stall converter for $100. What size cooler?

[Fury Boy]

and the headers are hedmans

[rumblefish360]

Hey Fury Boy..

How many miles on the eng. If it has a lot of miles, the milled heads will be to much for the bottom. Dad's right. You;ll blow out the bottom.
Go with the matched set from the maker. The stock springs should be changed out for new ones.
The header wrap is best for protecting the starter. I have had used it in the past. I didn't like it. It hammered my heders with heat fatigue.<sp>
As far as gaskets, I alwats used 1 of 3 kinds with no problems. MOM MoPar, Fel-Pro, Mr. Gasket Ultra seal. As long as there put on right, you'll have no problem.

[Fury Boy]

Dear rumblefish360,
don't know any thing about how many miles on the engine, but I am planning to check the main bearings and everything first, I just haven't got to it. I don't think there are that many miles on the motor because the original looking paint is still on pretty good(hasn't flaked all off anyway). We just plan on running it till it breaks and then we'll build a race 440.

[Christopher]

Milling heads blowing out the bottom?? Not sure what you mean by that Rumble.Milling the heads won't hurt a thing.In fact a .030 cut would raise the compression up to about 9.2,which will work fine.Also it wouldn't be a bad idea to have the valve guides at least knurled,the valves ground and have the top of the guides cut for PC valve seals.Change the retainers as well,the chrome moly ones and new locks from either Mopar or Comp Cams work well.If this converter stalls out at 4K,I'd use the 4.56 gears and a 28 inch tall tire on a 8 inch wheel(assuming you will use slicks)Definatly change the valve springs,otherwise the stockers will not let you rev much past 5000.You should run this engine to about 6200-6500 rpm.My factory stock bottom end 383 in my Road Runner was set up almost the same way parts wise and it was running 12.20's with a 4.88 gear and 3800 converter.

[cruzerjd]

Hey Furyboy, on another subject, how bout them Ducks!, three different times i gave up on em and they still came through. cruzerjd

[Fury Boy]

THE DUCKS ARE DOING GREAT!!!
Oranges or Roses?
and thanks for the head and gear suggestions.

[cruzerjd]

I'm hoping for Oranges but I think we'll get juked again. Roses would be fine though, bt we gotta watch out for the Beavs too. cruzerjd

[Fury Boy]

So how much horse power do you think this thing can put out?

[Christopher]

I'm only being realistic as none of my engines have ever seen a dyno,but I'd say about 375-400 Hp.

[rumblefish360]

Christopher:
When u beef up or renew a part. The counter part may not be up to par.
Heres another EX: New eng. + old tranny = blown tranny.
New head will seal so well that the bottom, thats old will fail. Typical on old HI milage engs.
Have you never exper.this?

[Fury Boy]

Another Old question, I got a new Idea. There's a set of old 516's sittin' in the back of the shop. Would my compression ratio be better if I swapped these heads onto my 383(346s on their now)? Head flow doesn't really matter as much w/ this cam size does it? Which is more important in this application, flow or compression?

[This message has been edited by Fury Boy (edited November 14, 2000).]

[rumblefish360]

Your compresion ratio will go up if the head chamber is smaller. The cam you have, I can't find in my new comp catolog. But it seems that the ones with 230@.050 look for about 9.0-1 to 10.0-1.
As far as head flow ... more the merrier. Even if the cam is small. Thats were the power is !!!

[ChristianCuda]

Fury Boy your 516 heads are closed chamber versus the open chamber 346 heads so Compression can go up as much as a ful point depending on your pistons and actual compression ratio now.

Christian

------------------
Http://ThunderRacing.Knudstrup.net/

68 'Cuda 383 Best of 8.363@83.78 in the 1/8mile which is a mid 12 with a 1.89 60ft
Formula S recreation not original but making like they should have at the factory) Working on adding EFI
69 'Cuda Race Parts Car
76 Duster 273 recent transplant
95 Neon 2.0 SOHC best of 16.96
84 Dodge Ram D50 transplanting 360

[Fury Boy]

Does any one know the flow for a 516 head compared to a 346( both stock)?
Also I am now thinking the Carter mechanical fuel pump( the "strip" model, 8.5 psi, 120gph). Are there any advantages lost using the mechanical instead of electrical fuel pumps? Keep in mind that this is a drag car
------------------
Keep'n it Alive
******************
'63 Plymouth Fury 2 DrHT
* '71 383 Torker Man.,
Comp 280H cam,
Predator Carb

[This message has been edited by Fury Boy (edited November 17, 2000).]

[Chargerchuck]

Fury Boy, I didn't read through all of the previous messages to see how you came up with the 516 and 346 heads. To me its a no brainer; the 516 heads use a 1.60 exhaust valve compared to the 1.74 inch on the 346. The only advantage to the 516 heads would be the smaller combustion chamber, but between the bigger valves and better flow of the 346 (add a little shaving if you want) these later heads should work much better than the 516s. I believe they started using hardened seats on the 346 heads, which would be an added benefit. You can go with bigger valves on the 516's but you still have flow issues.

[PRO]

Heres my 10 cents worth,new main & rod bearings,oil pump and rings,no machine work if everything plastigauges ok,just hone it of course be sure that all the piston skirts are intact etc,mill the 346s .060 and use mp steel head gaskets(.018)remember the Comp cam has more duration and will lower your cranking compression,run a Holley 750-850 and a 3000-3400 converter with 3.91s,youll make an honest 360-375 ponies...& add 150hp of N2O and take bets on how long itll hang together!!I did this exact same thing on a 72 440 and it lasted 3 years and 35K and ran 12.0s....PRO....(516s have smaller exhaust valves and the port floor is raised )

[This message has been edited by PRO (edited November 17, 2000).]

[Fury Boy]

I knew the 516s were bad, but i didn't know that bad! Thank for all the replies! Maybe I can get a web site up about my times and modifcations here pretty soon.
so what do you think I should run my timing at to get good power(mostly top end) I don't
need very much lowend because I am putting a high stall converter in it(looking at 4000 rpm, but if that doesn't work I'll probably get a TCI Street Fighter converter(3000-3500 stall). My gears will probably be 4.10-4.56s and I want to run a Strange spool. So say the car weighs 3200 lb w/ the driver(the car has a lot of aluminumn and fiber glass on it, the inner fenders were cut out to) does any body dare project the times it will run.
The person who had it before me was running an 11.30 with a 500 horse 440.

[bbaspense]

I wouldn't run a Mopar without inner fender unless there was a bar from the firewall to the frame. The inner fender and rad support are an important part of the integrity of the front end.

I run a stcok 400 with stcok parts and poorted heads with a 484/292 cam. Great top end and I never lost the bottom. I have 3 seasons on this motor without a prob.

I made the mistake of big hp and stock tranny. I quickly broke the stock tranny.

Jason
indychamp@hotmail.com
Jason's Aspen/Volare Club http://www.geocities.com/indychamp