Original '84 Z28 w/ L69 is it worth keeping and upgrading?
12-21-2005, 09:27 PM
#1
Registered User
Thread Starter
Join Date: Dec 2005
Location: Clarksville, TN
Posts: 61
Original '84 Z28 w/ L69 is it worth keeping and upgrading?
I have an all original 140K miles, 1984 Z28 with the H.O. 5.0 L69 (with all emissions crap) and a newly rebuilt/beefed-up 700R4. I have seen a lot of articles about 300+hp mods for the L69, but is it worth beefing up or should I swap in an LT1 or 400ci engine etc.
Note: My exhaust system is really bad, so before I dump a bunch of money into a new one I first need to decide what SBC or Big Block may be dropped into my engine bay (see below).
Choice #1: I have a buddy that wants to sell me an LT1 he pulled out of an '94-'96 Impala ($350), and it is complete with all acc., computer, and wiring.
Choice #2: My Father-in-law has a 400ci engine (complete) that he is willing to part with also (free).
Choices choices ... but I want good fuel economy (20+mpg), and I'm on a tight budget. My wife really really really hates my money pit (new paint and body panels (northern car), mostly new interior, timing chain, tires, T-Top seals, etc. $$$$).
Thanks.
Note: My exhaust system is really bad, so before I dump a bunch of money into a new one I first need to decide what SBC or Big Block may be dropped into my engine bay (see below).
Choice #1: I have a buddy that wants to sell me an LT1 he pulled out of an '94-'96 Impala ($350), and it is complete with all acc., computer, and wiring.
Choice #2: My Father-in-law has a 400ci engine (complete) that he is willing to part with also (free).
Choices choices ... but I want good fuel economy (20+mpg), and I'm on a tight budget. My wife really really really hates my money pit (new paint and body panels (northern car), mostly new interior, timing chain, tires, T-Top seals, etc. $$$$).
Thanks.
12-21-2005, 09:41 PM
#2
Registered User
Join Date: Jul 2001
Location: Ft Benning, GA.
Posts: 51
Re: Original '84 Z28 w/ L69 is it worth keeping and upgrading?
It's all about what you the car to look like when your done, so whatever you decide just remember you will always go over your budget. And if I where you I'd go for the LT! swap!
Last edited by ZZ17IROC; 12-21-2005 at 09:50 PM.
12-21-2005, 10:48 PM
#5
Registered User
Join Date: Oct 2005
Location: Bakersfield
Posts: 685
Re: Original '84 Z28 w/ L69 is it worth keeping and upgrading?
Avoid the B body LT1, it had iron heads and a smaller cam producing a bit less hp. Since the 400 is free, get the block machined and drop in a 4" crank and have a 427. 
12-22-2005, 11:16 AM
#8
Registered User
Join Date: May 2004
Location: Ewing, NJ
Posts: 714
Re: Original '84 Z28 w/ L69 is it worth keeping and upgrading?
Is that a 400ci sbc that he's giving you? If so, you'll want to get that. Dollar for dollar it will destroy that LT1, and it will be a much easier swap. Toss a nice Holley vac. secondary on top, and you'll have decent milage with the overdrive in the 700R4.
- Justin
- Justin
12-22-2005, 04:06 PM
#9
Registered User
Join Date: Feb 2002
Location: Talbott, TN
Posts: 519
Re: Original '84 Z28 w/ L69 is it worth keeping and upgrading?
I would go with the 400. I would think it will be set up a lot easier than puttng the LT1 in and I would also think that here would be more parts potential for the 400 than the LT1.
I like the idea of the 427 u even a 400 small block Chevy is pretty cool.
I like the idea of the 427 u even a 400 small block Chevy is pretty cool.
12-22-2005, 04:16 PM
#10
Registered User
Join Date: Oct 2005
Location: Bakersfield
Posts: 685
Re: Original '84 Z28 w/ L69 is it worth keeping and upgrading?
Originally Posted by pearlpurple
I would go with the 400. I would think it will be set up a lot easier than puttng the LT1 in and I would also think that here would be more parts potential for the 400 than the LT1.
I like the idea of the 427 u even a 400 small block Chevy is pretty cool.
I like the idea of the 427 u even a 400 small block Chevy is pretty cool.
Damn I just noticed you are from Timmins, I bet you have long *** winters. One of my best friends lives in Sudbury.
12-22-2005, 05:45 PM
#11
Registered User
Thread Starter
Join Date: Dec 2005
Location: Clarksville, TN
Posts: 61
Re: Original '84 Z28 w/ L69 is it worth keeping and upgrading?
Yeah, the 400ci engine was my first choice, but then I had flashbacks of my mothers old '77 Trans Am with the 6.6 liter only getting 10mpg, and then doubt started to set in my mind. I know the Impala LT1 would get between 18-28 mpg (I do mostly highway miles). The car has been a hobby, but it is about to be my daily driver/weekend cruise car.
Someone told me that the 400 Big Block (not sbc) will not just "drop in". That I will need to change a lot of parts to make the Big Block drop into my engine bay, i.e. buy motor mount adapters, trans adapter, etc. I'm know my way around a car, but I've never done an engine swap.
I believe it came out of a '70 or '71 Chevelle or El Camino. I will ask my wife's Step Dad, the holder of the engine. It was originally going to be dropped into a Modified, but the rules changed, and now he has to run a 358ci.
Someone told me that the 400 Big Block (not sbc) will not just "drop in". That I will need to change a lot of parts to make the Big Block drop into my engine bay, i.e. buy motor mount adapters, trans adapter, etc. I'm know my way around a car, but I've never done an engine swap.
I believe it came out of a '70 or '71 Chevelle or El Camino. I will ask my wife's Step Dad, the holder of the engine. It was originally going to be dropped into a Modified, but the rules changed, and now he has to run a 358ci.
12-22-2005, 05:52 PM
#12
Registered User
Join Date: Oct 2005
Location: Bakersfield
Posts: 685
Re: Original '84 Z28 w/ L69 is it worth keeping and upgrading?
A 400 is a SBC, and was available in Chevelles. There were 396 big blocks that actually displaced 402 CI, but I don't know of a "400 big block".
12-22-2005, 05:59 PM
#13
Registered User
Thread Starter
Join Date: Dec 2005
Location: Clarksville, TN
Posts: 61
Re: Original '84 Z28 w/ L69 is it worth keeping and upgrading?
You're right. Now I've read a lot of Chevy-Hi-Po and Hot Rod Magazine stuff on Q-Jets being reliable and stuff, but why should I consider keeping that carb over the carb that is on 400? Would there be a big difference in fuel economy? Does the Q-Jet have to retain its sensors?
12-22-2005, 06:06 PM
#14
Registered User
Thread Starter
Join Date: Dec 2005
Location: Clarksville, TN
Posts: 61
Re: Original '84 Z28 w/ L69 is it worth keeping and upgrading?
Hey, 91-Z28, I just saw your video ... THAT IS WHAT I WANT MY Z28 TO DO!!! I've tried to make it a sleeper in appearance, but yeah man, I want to shred rubber and have cars like my wifes Focus (which she is slowly upgrading) eat my smoke and rubber chunks.