Another Mark Jones 496 ENGINE
Thread Starter
Racer
Joined: May 2010
Posts: 290
Likes: 20
From: MEMPHIS TN
Another Mark Jones 496 ENGINE
I purchased a 496 from Mark Jones for my 69 corvette convertible 4 speed. I drove up when he had it ready & got to see it run on the dyno. I can't speak highly enough on how great my experience was with Mark. I have been completely satisfied with the build. It's a 496 with 049 iron heads, small isky roller, 850 holley carb made 682hp & 687ftlbs on his dyno. I've been beating the hell out of it on the street for about 4-5 months now. I'm running a m20 4sp with a centerforce dual friction clutch & stock 3:36 rearend 2" headman headers & full 3" mandrell bent custom exhaust with race pro mufflers. I know my time is limited on the rear end & the transmittion but until then I'll keep enjoying it. The motor idles nice at 850rpm the driveablilty of this thing is amazingly nice, smooth & calm. One would find it hard to believe that it makes almost 700hp. Even my grandmother could drive this to the grocery store. Once it's rolling, it's unbelievable how hard it pulls to 6000 thru all gears. No oil leaks & never runs over 180 even in stop & go traffic in Memphis. Thanks again Mark Jones Vortec Pro
Team Owner
Joined: Oct 2004
Posts: 81,241
Likes: 3,063
From: altered state
St. Jude Donor '05
Awesome! Everytime I think about a larger stroker sbc or LSx I see another example of marks motors.
For the money just cant beat that kind of reliable power. Maybe one day
For the money just cant beat that kind of reliable power. Maybe one day
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Le Mans Master
Joined: May 2006
Posts: 9,993
Likes: 1,136
From: League City Tx
Congrats on getting it finished David... My MJ496 is still kicking... Been a great engine. Over 12k miles on it now, and about 50-60 1/4 passes.. This thing runs like a Swiss watch.
I'd almost like to do a head/cam upgrade and get it over 700hp but.. I probably won't mess with it... It just drives too nice.
I'd almost like to do a head/cam upgrade and get it over 700hp but.. I probably won't mess with it... It just drives too nice.
Melting Slicks
Joined: Jul 2009
Posts: 2,091
Likes: 40
wow ...awesome , thanks for sharing the results 
beautiful ride with 700 easy going HP "reliable " with all the sensors and computers and junk gone.and crazy wiring harnesses
absolutely killer car. .....sure you
can't stop smiling tooling down the road
Love it.
beautiful ride with 700 easy going HP "reliable " with all the sensors and computers and junk gone.and crazy wiring harnesses
absolutely killer car. .....sure you
can't stop smiling tooling down the road
Love it.
Burning Brakes
Joined: Jun 2003
Posts: 1,022
Likes: 6
From: CT
Looks good! With the stock valve covers, cast heads, and drop base air cleaner it looks like a mild/stockish big block...but with 680hp!! be careful if you plan on running drag radials or slicks with that 4spd...I've cracked the cases on 2 4spds and completely blew up my stock diff with only 500hp, drag racing and launching hard on 275/60/15 MT drag radials.
Do you have a videos of it running/driving?
Do you have a videos of it running/driving?
Thread Starter
Racer
Joined: May 2010
Posts: 290
Likes: 20
From: MEMPHIS TN
David
Pro
Joined: May 2013
Posts: 672
Likes: 31
From: Rapid City South Dakota
I'm currently assembling a very similar car, 69 t top with tko 600 5 speed, Mark Jones 496. I've been told you can't get 3" exhaust through the stock trans crossmember, therefore I went with sidepipes....how'd you do it?
I've been going thru the learning curve with the 12 bolt upgrade with Toms' parts. I guess I'm surprised you haven't grenaded something in the rear end!
Did you have to take the body off the car to run a bigger fuel line? I'm told it's that big of a job.
Last edited by lurch59; Aug 19, 2013 at 01:11 AM. Reason: forgot one question
Thread Starter
Racer
Joined: May 2010
Posts: 290
Likes: 20
From: MEMPHIS TN
The compression is 9.7 to 1, and yes you can install 3" through the crossmember with no modifications to it, its tight but fits with no rattles at all. Are you running stock 69 side exhaust? My car had stock side exhaust and I wanted to put it back on but its way to restictive for this motor. Fuel line is easy, I left the stock line in place and just ran aeroquip 8n black hose from tank to carb along the passengerside fram rail. My next purchase will be a 5 speed, looking at the Legend 700 from Keisler, Let me know if you have any other question on your build thanks David
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Burning Brakes
Joined: Jun 2003
Posts: 1,022
Likes: 6
From: CT
The compression is 9.7 to 1, and yes you can install 3" through the crossmember with no modifications to it, its tight but fits with no rattles at all. Are you running stock 69 side exhaust? My car had stock side exhaust and I wanted to put it back on but its way to restictive for this motor. Fuel line is easy, I left the stock line in place and just ran aeroquip 8n black hose from tank to carb along the passengerside fram rail. My next purchase will be a 5 speed, looking at the Legend 700 from Keisler, Let me know if you have any other question on your build thanks David
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This isnt a direction corvette kit but easy to make work. Just giving you another option to check out.