El Camino Central Forum banner

1 - 19 of 19 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter #1
After purchase, I had 2 hours driving my 86 Choo Choo home last week to ponder what to do about the lack of power that the 305 has. Leave it stock (more value?) or slide in another motor to make it more peppy. I still have not made up my mind. Hence the forthcoming questions!

I started researching this swap as soon as I got home and continues to this day. I think I have decided on a L31 Vortec, if I decide to proceed. I had a used L31 fall into my lap yesterday. Harness was cut off, so no electrics included. Motor is complete otherwise. I plan on giving it a once over,, button it back up with new gaskets and let it sit on my stand until my research is done.

Part two of my plan is fuel injection. There are so many stand alone FI kits out there that it makes my head spin. FiTech, Holly, Summit, Edelbrock etc. I do not know much about FI and thought i would ask those that have gone before me what intake, FI unit and pump that you recommend.

Also any other tidbits I might need to know to help make this decision any easier (harder?)!

I am not a swap newbie, but I am close. I did an LS3 EROD swap into my 86 Trans Am with a lot of guidance from the Trans Am community (forums). I never drilled a hole during that swap in case I wanted to go back to stock.

So far I have not found a comprehensive post on this swap, during my hours of searching. Maybe this community can point me in the right direction!

Thanks for reading and I eagerly await your recommendations/suggestions!
 

·
Senior Member Participating Member
Joined
·
813 Posts
Whymee, A wet clutch?:yell:
 

·
Registered
Joined
·
1,021 Posts

·
Registered
Joined
·
19 Posts
Discussion Starter #5
Did you do the LS3 EROD because you live somewhere with strict emission control laws? Do you still live there?
Rick

Rick,
I did the EROD install because I bought the motor for a good price. For this car I was buying new. Had to drive a bit to pick up, But for a good deal who wouldn't!


No emissions inspection in WV, and yes I still live here.
 

·
Premium Member
Joined
·
1,357 Posts
I've heard good things about the Holley Sniper system. And since you are in a state with no emissions requirement, that shouldn't be a regulatory problem.

I'm running a Tanks, Inc fuel pump inside my fuel tank to get me the 58 psi needed at the fuel rail. Your Erod motor would have needed something very similar.

Rick

Sent from my SM-G965U using Tapatalk
 

·
Director Region 6 (FL) - 2017 Founders' Award Reci
Joined
·
4,566 Posts
Whymee , Since you want to wake up your 305 engine/performance , a decent powered LS swap is a great idea . In the meantime , while you think about how to proceed , a good , reasonably inexpensive and easy way to do it is to change the gear ratio in your rear end . Depending on what trans and final gear ratio your Camino presently has , a gear change might add some welcomed performance . I have a Tremec TKO 5-speed ( final ratio of 0.68 ) , that had a 2.41 factory rear end ration . 464elky replaced my rear end 2.41 gear ratio ( great for the highway ) to a 3.42 and it made a major improvement in take off , overall performance and is still reasonable RPM wise on the highway . Depending on how much LS power you are thinking of adding , the factory 7.5 in. rear is fine up until around 350 H.P. , depending on how much accelerator mashing you do . More H.P. and mashing would justify perhaps a change to a stronger 12 bolt rear . Use the search feature to call up a number of informative posts on rear end ratios and rear end strengths that other members have posted . I run a non-electric Quadrajet that 464elky rebuilt for me and have had around 6-7 years of great , trouble free performance . I hope to upgrade my 350 engine at some point and plan on a Fi-Tec injector . 464elky has installed almost a dozen of them on various rides including Caminos and everyone is happy , the price and reasonable easy of installation is hard to beat .
 

·
Registered
Joined
·
1,021 Posts
The L31 is a good Vortec head engine. It can make a lot of power with the right cam.

I have a RamJet 350 in my '55 Belair. That engine IS a 4 bolt main L31 with a different cam, 1.6 roller rocker arms and of course the Multiport EFI setup and it's MEFI-4 ECM.
Makes 350HP and 400 ft-lbs of torque.

I have a stock 436HP LS3 in my Corvette and I can tell you that my RamJet has a little better low-end torque than my LS3 has. LS3 beats it on top end though starting at around 4,000 rpm. Redline on the RamJet is 5,500 and the LS3 will pull strong all the way to it's 6,600 redline.

My recommendation to you would be to put the same cam, rockers and valve springs that the RamJet has on your L31. Then go with a Holley Stealth Ram EFI kit for Vortec heads.
You will also want to go with nice set of headers and a 2 1/2" exhaust setup with an H or X pipe.
Also take the time to do a true cold air intake pipe setup.

Yup, you would have a lot of money in it. But it will be a great performer and still retain that great looking Chevy small block engine under the hood.

RamJet 350:


LS3:
 

·
Premium Member
Joined
·
63 Posts
A friend and I just completed the installation of a new L31 in his '70 El Camino. It's a direct drop in replacement for the 5.0L. We installed a more aggressive Comp Cam and LS3 behave valve springs with reduced height retainers to prevent interference with the valve guide with the higher lift cam. Had to change the flex plate to an external balance L31 unit. The l31 is an external balanced engine and if you don't have the correct balancer and flex plate it will shake itself apart. There is no provision for a fuel pump, and we use the FiTech Easy Street EFI system on this car and about 4 other friends cars. You need a hi pressure fuel supply for the FI system. I have used several different systems, but have finally settled on a 89/96 Buick Roadmaster/Caprice Station wagon tank. I purchase a new sending unit/fuel pump from Rockauto for about $90. The fuel tanks are about $ 75 from a wrecking yard and they are a bolt in. You can use the original fuel line for hi-pressure fuel and run a new return line paralleling the existing line. The FiTech requires about 4 wires to run. +12V constant, +12V Ignition, Tach input, and power output to the fuel pump. It needs temp info (supplied sensor) O2 Sensor input (Supplied O2 Sensor). I have a lot of data on al of these things. I am presently finishing up a LS3/6L80E for my '87. Send me a PM and we can exchange phone numbers and I can give you all the data I have.
 

·
Registered
Joined
·
1,021 Posts
... I am presently finishing up a LS3/6L80E for my '87.
Are you documenting this install on this or any forum? I'd like to follow if you are.
 

·
Registered
Joined
·
11 Posts
I installed a Holley stealth system in my 68. I used a tanks gas tank with a walbro internal pump. I put the filter and corvette regulator at the tank and used the factory 3/8" fuel line. the fuel line comes up near the area the old mechanical pump was, and into the Holley supplied line, which looks like the old Holley dual feed line. I hid the ECU under one of the inner fenders and ran the harness around the back and into the back of the engine. I used a pertronix small cap HEI, which is controlled by the ECU. Most people looking at the engine think it is a dual inlet Holley carburetor. I added the Holley fuel pressure sensor, so I can read the fuel pressure at the engine, and adjusted the bypass regulator accordingly to have the proper fuel pressure. When I rewired the car I installed a power feed from the fuse block to the rear of the car. I ran a line from the Holley ECU that line and now the Holley ECU runs the fuel pump through a relay. With the trans in neutral you can turn on the key, and after 10 seconds hit the starter and it fires up almost on the first revolution every time. Great system.
 

·
Registered
Joined
·
19 Posts
Discussion Starter #12
Excellent comments gentlemen!

I picked up a used L31 the other week. Tore it down to freshen it up. Lo & behold it had rust in one of the cylinders. Major bummer.

I still am going to do the L31 and stand alone EFI, just not as fast as I thought. I said screw it, going to go new L31 from GM. Should of done that from the start. Going to take a few weeks to squirrel away a few pennies.

I was driving the Elky this afternoon and she dropped a cylinder. Upon closer inspection it turned out to be a mis-routed plug wire. A trip to NAPA and all is good in Whooville once again.

I will probably do a build write up on the swap. I will keep this post informed as to where it will be located.

Happy 4th of July ya'all!
 

·
Premium Member
Joined
·
63 Posts
L31 Prices

The L31 we put in my friends '70 was bought from a dealer on the East coast. It ended up at about $1875 delivered to his door. Several small differences on the L31 and earlier SBC's. You can find all the info on various forums.
 

·
Premium Member
Joined
·
63 Posts
Are you documenting this install on this or any forum? I'd like to follow if you are.[/QUOTEThe

LS3 is really a L76 that I have removed the DOD on it. Already had all of the other LS3 items, except 12 Cubic Inches. I am using as much original GM parts as I can. I find that GM parts are usually less expensive, and you don't have to worry about fit and function. Now has LS3 cam, beehive valve Springs, new valve seals, new lifters (LS7), cam gear, chain tensioner, Cadillac CTS-V oil pan, GM LS3 oil pump (L76 has a very high flow rate pump that can suck the pan dry on an engine without DOD). Reworked the rockers with Michigan speed roller bearings and full roller trunnions. Now finishing up mocking up front accessories. Lot of unexpected differences in down under built L76 accessories. I have all of the accessories on and have the proper serpentine belt. Looks factory. I think I will start a build thread and document most of what I have done, and what I do in the future. Still have the harness to rework, I need to mod the valve body in the 6L80E to fix some factory design problems, and replace the TC. In all of the investigation I have done on the 6L80E, all of the failures have been the TC shredding its clutches and trashing the rest of the trans with debris. My TC is still good, but I am replaced with a new one as the engine/trans has 108K miles.]
 

·
Registered
Joined
·
19 Posts
Discussion Starter #15
The L31 we put in my friends '70 was bought from a dealer on the East coast. It ended up at about $1875 delivered to his door. Several small differences on the L31 and earlier SBC's. You can find all the info on various forums.
I was just thinking of asking (posting) where is the best price on a new L31.

Best price I have seen is $1999.99 at Scoggin Dickey (includes free shipping)

https://sdparts.com/i-19928727-gm-engines-12530282-vortec-350-l31-new-crate-engine.html?gclid=Cj0KCQjwpPHoBRC3ARIsALfx-_KFqUwjOMsvqTdPQpnUp4e1s-whOS_J8FdqFqYeZfdaGaRcaifHOMUaAqFGEALw_wcB

Anybody else know of a better price?
 

·
Supporting Member
Joined
·
4,418 Posts

·
Registered
Joined
·
1,021 Posts

·
Supporting Member
Joined
·
4,418 Posts
The link you provide that shows $1,599 is an ATK remanufactured engine.
My bad- didn't study it enough after hitting search...
 
1 - 19 of 19 Posts
Top