I have a 78 Anniversary L48 and am tired of feeling like I am driving Ms. Daisy. Was thinking of saving up over the winter to drop in a 383, but was wondering if it would be worth it on an automatic with a 3.08 rear end. Thoughts?

 

Better believe its worth it!!
Youll wonder how you ever drove it a day as it is now once you have the 383. A 700r will just add to the fun and your mpg. You will LOVE it!
Plus you can cruise at 75-80 all day long and the motor isnt even awake
Done right....youll never believe it was just another 33 ci. Torque is fun and youll automatically have more hp as its bigger period.

What kind of power or driveability are you looking for
Budget
Know wiht the 308 gear you wont want a bunch of cam but if you build for torque properly you shouldnt need it. Small converter at most.

 

Change her name to something other than Daisy. She may not like being called Daisy.

Ask her.



(Pssst. What's not to like about a 383?)

 

I'm in the process of the same upgrade although I have a 4 speed with 3.36's.

From all I've read, there's almost no going wrong with a 383.

 

YES. Depending on the motor you looking at almost doubling the HP and a 1/3 more torque. Way different animal.

Get a 383 with the same head bolt patterns for the accessories and exhaust and you can retain all the stock stuff and exhaust if you want. Or go as crazy as you like.

While its out put a shift kit in the trans (cheap). The extra torque of the 383 will really surprise you and crisp shifts from the tranny will put a smile on your face. The 308's are pretty steep but the motor will wake it up drastically if you don't want go and cant go to higher gear later.

 

Thanks for the replies! I just need the extra convincing to push me off the edge.

@ cuisinartvette - I'd like to be able to spin the tires and know that I can beat the minivan next to me if I want to. I was looking at the following three:

http://www.jegs.com/i/Chevrolet-Perf...oductId=752396
http://www.jegs.com/i/Blueprint-Engi...rentProductId=
http://www.jegs.com/i/Blueprint-Engi...rentProductId=

@ Easy Mike - The Ms. Daisy was a movie reference - her real name is Stella and I am trying to help her get her groove back...

mysixtynine - could you elaborate more on the shift kit? I already converted to 2.5" duals and would like to replace the manifolds, but no headers.

 

First two links are 350s?

3rd is a basic flat tappet 383. I dont know that the cam they put in will like your 3.08 gear at all. Little on the biggish side. Change that and it should run good

I wonder what VortecPro could do you up a mild 383 for. Might be a good idea to try him. Hes cost concsious but build a very sound and powerful motor. not like the cheap junk out there on ebay


Should really consider some type of header to compliment your new found power. Even a 3/4 length or shorty...anythings better than the manifolds
(porting them is useless been there done that waste of time and $)

 

I am going between the 355 and the 383, but leaning towards the 383. What cam would you suggest for the engine/transmission on the 383?

Thanks for the heads up or VortecPro - is he on the forums frequently?

 

Theres millions of choices no "one rule sizing" but if it were me something like an Isky 270 mega cam is the biggest Id go with that gear....use a 2400 or so stall. Lunati makes a decent line of flat tappets also
I would not put a Comp cam in if you gave it to me.

Others will give their choices.

Many of us have done up a 350 every which way in search of "it".
IT comes in the form of more torque. That longer arm in the crank is what will do it for you every time.


Yes mark aka is VortecPro hes on here.
Has a rep for pulling good power from basic pieces and they stay together. Dynoed ready to go.

http://www.vortecproperformance.com/

 

Mcjacks makes some very nice manifold replacement type headers that bolt right up to the old system but the original rams horns are still a pretty good design.

http://www.vetteheaders.com/servlet/...rvette+Headers

The shift kit is something you can do on your own in the trans. You pull the pan and valvebody (just a bunch of bolts) and carefully follow the instructions. I don't recall what trans you have but here is an example. I put this in one of my cars and it would chirp 2nd and 3rd everytime.

http://www.jegs.com/i/B%26amp%3BM/130/30228/10002/-1

 

I agree, completely worth it. Just do your self a favor and moth ball your original l48. deffinately go long tube headers, 1.75'' for a 383, youll need to figure out what rpm range you'll want power at and go from there, if you intend to keep the 3.08 rear gear, you'll want to keep the max rpm 5500 to 5800 range, as said before, vortec pro seems to have a good reputation so does cnc-motorsports. Don't be afraid to go as high as 2500 rpm on the stall converter depending on the combination.

 

While saving and researching engine options, recurve the distributor, advance the cam 4 degrees, put in a test pipe. You can do this for less than 100.00 and it will drive like a different car!

 

Yes definitely do the 383, it won't even know there was a 3.08 in the rear. I used to have a '78 silver anniversary car with TH350 w/ 3.08. I couldn't get that L48 out fast enough. Built a 383 for it with some old Brownfield heads and used a mild Engle solid flat tappet and if I recall was less than 230 duration. Torque converter was a 10" Art Carr 2,500 stall. The intake was the Holley LT-1 Z/28 copy with a Holley 750. Smoking tires at will was no problem.

 

Thanks for all the info and Mark's website, cuisinartvette - I will definitely contact him and see what he can do. I was drooling over some of those videos

@ mysixtynine - thanks for the link and info on the shift key. I have a TH350 and could definitely benefit from that. Those manifolds are awesome, but not cheap!!! Not sure I want to spend that much on the manifolds, though.

@ bluedawg - I definitely will hold on to my L48. I figured I might even rebuild it while it is out. As far as power band, I can never get my trans to shift past 3200 - 3500 so I would imagine that would be a good spot to focus.

@ Snoopysvet - What is a test tube? I did re-curve the distributor and have timing advanced to 14 initial, 34 all in @ 3200. Vacuum adds another 16. This did help a lot, but believe it or not, when I added the dual with Super Turbos, it felt like my car got slower. I just figured I lost it on the low end, but gained it on the high end.

@ Scott Marzahl - Thanks for the info...sounds like it will definitely transform her into a beast! Also, it looks like the 2500 stall is the consensus with everyone so far.


On a side note: I was also playing with the idea of upgrading the 383 to fuel injected and with the recent fuel injected thread that popped up, I am taking that as a sign from above (or at least that is how I will explain it to my wife) The EZ-EFI's are mentioned - are they any good?

 

I just got done upgrading the engine in mine. Huge difference. I went with a stick stroke and just cut the block and heads to get some compression

as far as FI

EZ maybe..cheap no way..I don't see the pay off, spend the money on a 700R4

 

Yep and a very good movie at that - Academy Award nomination for Morgan Freeman and Best Actress for Jessica Tandy.

The 383 will help with that.

 

[QUOTE=Jartanyon;1585023099]
@ bluedawg - I definitely will hold on to my L48. I figured I might even rebuild it while it is out. As far as power band, I can never get my trans to shift past 3200 - 3500 so I would imagine that would be a good spot to focus.
QUOTE]

Why cant you shift past 3500 rpm? Not that you always have to or will, but if you're new engine makes peak power at say 5500 rpm, you'll find yourself around that rpm more than you might think, I'll hit 6k in first and ease off in second not to break the speed limit only because I love the sound my vette makes from 3000 to 6000 rpm at wot, not to mention the enjoyment being pinned to the seat gives. The l-48 that you have now should pull to around 5000 rpm or so. After rereading your post, will it not hold the gear shifting manually, or do you not shift it manually?

 

And tune carb for performance. Nice exhaust/headers. Car will never behave the same. You may decide it is enough.

I won't try in this thread to convince you to use your L48 as a basis for a rebuild. However, if you are interested in what you can do and what 365hp/407tq feels like compared to your baseline stock performance, drop me a line. Perhaps I would have gone 383 but I started my hop-up 17 years ago and just finished my latest refresh (see signature).

 

I got the original l48 up to 259 rwhp with headers, heads, cam, intake and carb. If I gone better heads then, I may not have the 400 sbc I've got now. Your completely right about how a modded l48 feels compared to the stock 180 horse. But that compared to the same amount of modding done to a 383 would make you be a believer and the getting pinned to the seat from 2500 to 5000 rpm is alone worth the change in my opinion.

 

@ Bluedawg - I don't shift the car manually...i'm too afraid to on such an old trans! Extremely newb question, but do you let off the gas when shifting manually?

TedH - the carb has been rebuilt and the exhaust done along with the re-curve and the car does behave differently...just not at all enough for what I want. As I said before, I lost a lot on the low end going to 2.5" duals (probably from lack of back pressure). From reading a lot on the L48, it is very unlikely I will get the numbers I am looking for out of it. I will still be dropping you a line, though - i'm always interested in information