68 vette, 6.0 LQ9, Richmond 6 speed build
03-04-2010, 09:35 AM
#1
68 vette, 6.0 LQ9, Richmond 6 speed build I've posted bits and pieces of this over the last year, but now that I'm running out of stuff to do, I thought I would post the finished project.
I started with a 68 non-numbers matching SBC with 4 speed, big cam and 3.08 gears (not a good combo).
So after burning up a clutch this summer I decided on an LS motor. Original plan was for a 5.7 LS1 motor, but it was looking more like a 6.0 was a better choice for hp upgrades. So I ended up with an Escalade 6.0 LQ9 motor and added LS1 intake/injectors, 02 vette Z06 exhaust and "winged" oil pan.
I wanted to have a mechanical fan in addition to a temp and AC controlled electric since C3 vettes typically have cooling issues. So I kept the truck accessory spacing, swapped out the truck pulley onto an LS1 water pump and made my own accessory brackets. The Vintage Air Sanden compressor bolted to the passenget head, was spaced correctly for the truck pulleys, and fit over the A arm and under the hood in the cramped vette engine compartmment.
Modified water pump with truck pulley. The heater inlet/outlets hit the A arm, so the tubes knocked out, holes threaded and 90 degree fittings added. Oh yeah, the truck pump wouldn't work since the outlet would hit the DBW.
With a newly rebuilt 3.08 rear, a T56 0.5 or even aTKO 0.63 OD gear would be worthless, unless I was going 100mph. So I went with a Richmond 6 speed 3.28 1st gear, 0.76 OD. The trans is available with numerous choices for each gear.
I started with a 68 non-numbers matching SBC with 4 speed, big cam and 3.08 gears (not a good combo).
So after burning up a clutch this summer I decided on an LS motor. Original plan was for a 5.7 LS1 motor, but it was looking more like a 6.0 was a better choice for hp upgrades. So I ended up with an Escalade 6.0 LQ9 motor and added LS1 intake/injectors, 02 vette Z06 exhaust and "winged" oil pan.
I wanted to have a mechanical fan in addition to a temp and AC controlled electric since C3 vettes typically have cooling issues. So I kept the truck accessory spacing, swapped out the truck pulley onto an LS1 water pump and made my own accessory brackets. The Vintage Air Sanden compressor bolted to the passenget head, was spaced correctly for the truck pulleys, and fit over the A arm and under the hood in the cramped vette engine compartmment.
Modified water pump with truck pulley. The heater inlet/outlets hit the A arm, so the tubes knocked out, holes threaded and 90 degree fittings added. Oh yeah, the truck pump wouldn't work since the outlet would hit the DBW.
With a newly rebuilt 3.08 rear, a T56 0.5 or even aTKO 0.63 OD gear would be worthless, unless I was going 100mph. So I went with a Richmond 6 speed 3.28 1st gear, 0.76 OD. The trans is available with numerous choices for each gear.
03-04-2010, 09:51 AM
#2
Interior Since this was my mid life crisis car, I wanted to be comfortable, so AC was needed. Vintage Air makes a nice unit.
In addition, the vette had a 60 amp alternator, I think the LQ9 alternator is 140 amps. Old wiring, lots of extra electrics = fire. So I put in an aftermarket wire harness. It's been cleaned up quite a bit since this pic.
I wanted everything to look original outside and the interior so all the old gauges were used and the birds nest wiring cleaned up. Now each section simply plugs in with molex connectors.
In addition, the old vette had a mechanical tach. I found an Isspro tach in my shop that had the same sweep and even the same faceplate mounting holes. So a little hacking on the old housing resulted in this.
In addition, the vette had a 60 amp alternator, I think the LQ9 alternator is 140 amps. Old wiring, lots of extra electrics = fire. So I put in an aftermarket wire harness. It's been cleaned up quite a bit since this pic.
I wanted everything to look original outside and the interior so all the old gauges were used and the birds nest wiring cleaned up. Now each section simply plugs in with molex connectors.
In addition, the old vette had a mechanical tach. I found an Isspro tach in my shop that had the same sweep and even the same faceplate mounting holes. So a little hacking on the old housing resulted in this.
03-04-2010, 10:02 AM
#3
Engine goes in The engine and trans go in. I looked at the 1" setback plates but that put the engine really close to the firewall and resulted in the trans yoke within about 1/8" of binding in the trans. The standard mounts worked well, enough clearance in front and with the crank pulley too.
The trans mount was a bit of an issue. The 4 speed early vettes had welded in crossmember and it would have to be cut into if using a standard trans mount. So I just made my own that was about 1/2" lower and modified the mount to relocate it back. Originally I just cut the original vette mount off, but later made a new one out of thicker steel.
New stronger mount:
The trans mount was a bit of an issue. The 4 speed early vettes had welded in crossmember and it would have to be cut into if using a standard trans mount. So I just made my own that was about 1/2" lower and modified the mount to relocate it back. Originally I just cut the original vette mount off, but later made a new one out of thicker steel.
New stronger mount:
03-04-2010, 10:10 AM
#4
Exhaust, etc An 02 C5 exhaust clears the Z bar, I kept the manual linkage with the Richmond, and the idler arm.
The problem with that exhaust is that it was made to fit around the winged pan, so it has an odd bolt pattern, non-symetric. About a week after I made these a company started selling the flanges..doh!
I had 69 sidepipes on the car that were pretty rusted so I got a pair of these and had a shop weld up a downpipe.
http://www.sweet-thunder.com/corvett...pes_68_74.html
The problem with that exhaust is that it was made to fit around the winged pan, so it has an odd bolt pattern, non-symetric. About a week after I made these a company started selling the flanges..doh!
I had 69 sidepipes on the car that were pretty rusted so I got a pair of these and had a shop weld up a downpipe.
http://www.sweet-thunder.com/corvett...pes_68_74.html
03-04-2010, 10:20 AM
#5
Intake If you look at the clearance between alternator, fan, belt, and AC compressor didn't leave much space for an intake air tube. I already had a hi rise L88 hood on my car, so there was plenty of clearance over the intake manifold. So I fabed a air tube out of fiberglass, cast over a foam float "noodle" and made a cold air induction air box over the intake manifold.
Finished car:
Oh yeah, and since this is my mid life crisis car, I replaced the black vinyl seats, "bun burners" on hot days, with cloth seats. It's supposed to be in the 50s this weekend so they'll get bolted in and time again for a drive.
Finished car:
Oh yeah, and since this is my mid life crisis car, I replaced the black vinyl seats, "bun burners" on hot days, with cloth seats. It's supposed to be in the 50s this weekend so they'll get bolted in and time again for a drive.
03-10-2010, 05:00 PM
#7
Seats installed Got the cloth seats in and finally found a reproducible problem. When travelling at low rpm in 6th gear, the engine wil die when the clutch is depressed for a prolonged time. Cause....no VSS. Fix....just ordered a Dakota Digital VSS, will hook it up this weekend.
