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More 383 exhaust manifold help

Posted By: court9155

More 383 exhaust manifold help - 04/12/11 05:24 AM

Here is my motor:

67 383
new rings/bearings
30 over pistons
balanced
stock valve size fresh 516 heads with hardened seats
mopar purpleshaft 474 cam
performer intake
holley 3310 750 vacuum secondary
mopar electronic ignition kit

vehicle:

66 charger
3.55 sure grip
2000-2200 stall
727

Now, I just want it to sound decent and do a burnout for my 4 year old son.

I could really care less about the overall performance I just happen to have these parts.

Right now I have a set of log style 66 non performance low block exhaust manifolds.

I was going to buy a set of 68 hp low block exhaust manifolds ( i know all exhaust manifolds were the same for RB and B with regards to this application)

BUT

My question is, when using TTI exhaust system 2.5 inch if I use a 2.5 inch pipe from the manifold flange out how much, if any power difference am I gonna see with the log manifolds versus the HP dealios?

Is it really worth the approximate $200 expense of the hp manifolds?

Plus I kinda wanted it to look pretty near what the under hood of a 66 383 charger would have looked like. I went through the trouble of using a 383 versus a 440 (tho I did have a cool little 400 at one time) I went through the trouble of hunting down the correct air cleaner and I even have the correct AFB or a non correct AVS if I decide against the holley...I also have an iron intake if i wanted to take it that far but painted turquoise you have to have a good eye to spot it and its just a 383 not a hemi car so who cares.....and the correct exhaust manifolds would be the log style from what I see on the web, in pictures and my father says.

So will I see a big torque or hp difference or should I just run what I have?
Posted By: Kern Dog

Re: More 383 exhaust manifold help - 04/12/11 07:24 AM

The 383 4 barrel engines equipped with the 727 trans had a factory stall speed range of 2350-2650 rpms. Now you are building a 383 with more cam and LESS stall. This will surely hurt your performance. You will certainly need a looser converter, something over 2800 at a minimum. I have a 3000 stall converter in my 440/493. Don't be afraid of using a converter with more stall. A quality unit will still move the car from a stop without excessive slippage.
As far as manifolds, YES, the performance will suffer. The 383 likes to rev and with the hotter cam, you will lose a little on the bottom end while gaining in the upper rpm range. The problem is, just when the engine is starting to make power, the log manifolds become a bottleneck. The Magnum HP manifolds are your best bet. In a totally stock app they are probably worth 10-15 HP over the log type. Add in more cam and rpm and the gain over log manifolds widens even more.
Posted By: court9155

Re: More 383 exhaust manifold help - 04/12/11 07:30 AM

Thanks for the reply. I dont have a converter yet so I can get one that I need. I just dont want to be on the converter all the time but with 3.55s that shouldnt be too big a problem.

Thanks for the input....these headers I have are lookin better and better to me everyday as is getting a performer RPM intake......


Dan
Posted By: dOrk !

Re: More 383 exhaust manifold help - 04/12/11 07:37 AM

court ........ DON'T pay attention to FRANKENberrie's post ... he has been all evening ! ...

You wanna' be a burn-out-King to the little dude ? ....HERE is the plan.

FURRget the HP mans ... just find a SINGLE WHEEL 2.76 gear (pig) and pop-it-in yeerr combo. THEN block-off the PASS SIDE rear wheel cylinder ...and then you will be able to do a BURN OUT that he will never forget.

YEAH I did this some years ago. With a 62 Fury I POPPED a new recap in something like 40 seconds !

Also I used a little ATF in the burn-out-box ! BOY that was fun ....

Smoke CITY !
Posted By: JohnRR

Re: More 383 exhaust manifold help - 04/12/11 12:41 PM

TTi doesn't make a headpipe for the standard log manifold so you'll have to source that part of the system yourself .
Posted By: dem440c

Re: More 383 exhaust manifold help - 04/12/11 01:17 PM

just my on the issue- to me, the car is either a factory perfect show car or it is a toy. There is no in-between to me. Once you step away from factory perfect then it's open season on the mods, make the car whatever you wish it was instead of what it is. Know what I mean? Obviously a lot of people will disagree with me on that and by all means feel free to disagree, just the way I look at it.

so if it was me.... iron logs get launched into the weeds and in go the headers. Look better, sound better, RUN better, easier spark plug access (changing that #7 on a big block with logs will ruin your day), and spend the extra dime on the soft seal gaskets for trouble-free miles.

....the one wheel peel with the brake cylinder blocked off cracks me up why didn't I think of that back when I was young?
Posted By: crlush

Re: More 383 exhaust manifold help - 04/12/11 01:29 PM

Spend the money on the converter, pick a brand you like, call them on the phone and give them your info and what you want to do (big burnouts) and they will set you up, just run a extra trans cooler inline with your radiator. Try adding a linelock and you will be your sons hero.
Posted By: RapidRobert

Re: More 383 exhaust manifold help - 04/12/11 01:37 PM

Andy made 550 horse w his 470 buildup using HP manifolds
Posted By: JohnRR

Re: More 383 exhaust manifold help - 04/12/11 02:21 PM

Quote:


....the one wheel peel with the brake cylinder blocked off cracks me up why didn't I think of that back when I was young?




Because you were a lot smarter than you think back then.

A friend on mine did that exact thing at in the burnout contest at Carlisle about 6 yrs ago, after being told it was not a good idea. Blew up the rear end when the spider gears seized on the cross shaft , rolled over the sprag in the trans and LUCKILY broke the mainshaft of the trans instead of grenading the front drum. Had to have the car towed back to NH after changing the chuck and the car still wouldn't move.
Posted By: court9155

Re: More 383 exhaust manifold help - 04/12/11 03:44 PM

Thanks for all the input guys.

I am buiding what I want not a show car:





I already have a show car and it honestly sux to own it (my 69 camaro).









Ill keep the 3.55s and I think I will put a line lock in the car but I will rig it to lock out the rear brakes so I have roll control.

Im still torn between of HP manifolds and headers but the logs are definitely goin in the weeds.

I never really thought of the 383 as a motor that wanted to rev, then again the only mopars I have owned and actually DROVE that werent my dads were a very very very tired 65 plymouth satellite 383 4 speed car with 3.91s (talk about burnouts when I was 16:



and a 66 charger with a 440 out of my 72 imperial.

So armed with this information I will probably go headers and performer rpm intake to compliment the camshaft in the car and the closed chamber heads (tho from what I hear from JohnRR are actually NOW 9.2:1 versus) still a decent compression for 91 octane.

Thanks guys.

Dan
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