The Official H-Body Internet Community

This guy on the FB Vega group is wondering about some good 140 performance mods.
Told him I'd help out here and post his inquiry.
Seems that he's done a lot already, but here's his post in blue (man 12:1 seems high for a street appl)...

just wondering how many of you guys and gals out there have run performance stuff on your stock vega 140 and if so what did you use and how well did it work?
Im getting ported head with cam in it and the 4bbl intake as well as 12:1 forged pistons and rods im just a little unsure about going that high in compression


I wondered about a stroker kit for them. They out there? Not sure if he wants to do bottom.

Thoughts?

Thx,
Mike

To start with, 12:1 for the street is quite high unless he wants a diet of racing gas. From what I have heard the four barrel is too much for the 140 unless it's the 390 Holley. There is not enough room in the block to run a longer stroke than stock. I think his best bet for performance would be forged 8.5:1 pistons and a turbo with water injection.

If he wants to stick with a N.A. engine I have a brand new intake manifold that uses a side draft 45DCOE Weber carb.

Dick

There is a dual Weber intake on EBAY right now. Chris Wheaton of Vegamods is the seller.

http://www.ebay.com/itm/71-77-Chevrolet ... c5&vxp=mtr

Dick

If he was to lower the compression he could go along the same lines as Hammerdown said but instead of a turbo get the Blower off of something like a Cobalt SS (really either way is way cool) and a Snow Performance water.... kit, maybe a necessity with that much "squeeze" with out the pressure adders . Just some fodder for kicking around, Harry

The 140 could be made to run pretty strong, but without a fair amount of head work, that 4 bbl carburetor is a waste. The intake valves are small, and the head is restrictive. I actually tried a 4bbl intake on a stock Vega in the 70's and it performed no better than the 2 bbl. Bear in mind I had a 2.92 rear, and a header. Maybe if I had it on a long stretch of interstate, it would have helped, but in town, (other than sounding fast), it didn't do much. I started autocrossing the car in 1975, and was hindered to some degree by SCCA rules. Eventually, I stumbled across what I found to be the best engine set up for my car, while staying inside the rules. I ran a 3.36 rear, a Cyclone "Bi-Y" header, an Accel super coil, and managed to find a 1971 2bbl camshaft. It was enough to get the car into the high 16's, at a little over 80mph (while set up to autocross), through the quarter mile on a miserably hot day. I do remember the old NASCAR "Baby Grand National" Monza's and Vega's running the 140, and making 150+ hp through a Rochester 2bbl carb. There is info out there, but it's hard to find.

I just googled "JV Reins". He drove a Monza in the old BGN class in the mid-70's, and later became an engine builder for Junior Johnson. There are a few articles, and photos of the class, including Rein's Monza. Fun stuff to look at.

Thanks guys for the feedback. I'll forward on to him.

Mike

The head he's tallking about is in my basement for an hour or so...he's on his way.
There was some decent porting and bowl blending and the cam is .480" on the intake side, so it's happy 3000-7000, without the 4bbl, I think you'd starve it. I ran this combo years ago with a header and a set of IECO 10.5:1 pistons. It was a little on the rich side, but i'll bet a jet or two down might have helped. MSD makes guts for the stock HEI add a good coil, and you'll be fine.
Just takes a little time to tune it, but I had lots of fun with it, expecially when the hood was popped up and people thought i was nuts...although they still do.

Holley 0-8007 - is a 390 cfm Vacuum Secondary 4-bbl that
works on a 140 with an Offenhauser dual port 4 barrel intake which has divided runners.

i would be the one who was looking for this info on high performance options for the 140, first i would like to say thank you to Mike for getting me to jump back on here and also to Jeff who i purchased the parts from, it was nice to meet you yesterday and its nice to know there is good honest people out there. Now to everyone else, thanks for your imput its very helpful, what i will be looking for is a set up that will be streetable as i plan to drive this car a lot in the summer, i currently have a 16 year old rebuilt motor, its maden start up was last summer, "that whole 16 story is a long boring one" my motor was built by opel enginering in streamwood illinois, a very reputible builder of racing motors, they sleaved my motor and gave me a 6 angle valve job and milled my head quite a bit to get me up over 9:1 compression "my mind remembers 10 being said but i could be wrong about that" im running a stock manifold with a holley 2bbl and a header, my rear end is a 3:36 and i converted my trans to the saginaw in place of the stock opel trans, my curent set up is not to bad as i can still break the tires loose in all 4 gears but i want a little more. duel side draft webbers peek my intrest but i worrie about setting them up as i would hate to set them up wrong and burn a valve or piston, i also have read a lot about turbo's for these motors and that sounds like a great option too "wont have any use for my new pistons though" i just dont know how to go about doing a turbo and what one to look for,i hear 8psi boost with stock pistons would net me about 220 hp which would be more than enough for me to enjoy my ride

Good to meet you Marc, looking forward to this summer and taking the Vega's for a crusise

Have you considered using a Cosworth head? It may take a bit of work but it could be worth the trouble.

Ken

There is a ported Spearco intake on Ebay, it may be a little too radical.
I think the Offy dual port is better for street usage.
http://www.ebay.com/itm/Spearco-Chevy-Vega-2-3L-2300-Ported-Aluminum-Intake-Manifold-4-Cyl-Drag-Racing-/171223331539?pt=Motors_Car_Truck_Parts_Accessories&hash=item27ddb4b2d3&vxp=mtr

We still race the 140 at our local Tracks.

My engine builder tried an experiment of making a Square Motor out of the 140.

A Square Engine is one that has the same bore and stroke.

He did this by putting Larger steel sleeves in the 140 to allow it to be bored to 3.625 in order to install the Quad 4 rods and pistons with the stock dish top piston.

Cut the 140 head .200 and installed the valves from a 2.5. Added a .525 lift cam

Add an Offenhauser Intake and a Holley 500 2bbl.

Add an exhaust Header. Tune the 2 1/2" pipe length to the engine. (You do this by using a yellow tire marker and drawing a line down the pipe, cut the pipe where the marker is not melted.) This makes a HUGE diff. in engine performance and lap times.

Turned it 6800 to 7000 RPM's and destroyed the competition.

Fastest Vega Dirt Car that I have ever seen.

They have since changed the rules to not allow this anymore. Only .060 max now.

I think he won 27 races in one season, running at 2 different Tracks.

any jetting info for the 390 holley carb?
getting ready to try something different on my 140 ieco setup..

I have been thinking of trying injection to get a good map on the fuel!!