1978 Oldsmobile Cutlass Supreme LQ4 + 4L80E swap
#81
Well, the 150 shot combo will never see the track. While driving long distance last week, the oil pressure went from 40psi at cruise to 20psi. Idle drops to near 10psi. Did some diagnosing today and it's probably a bad pickup tube o-ring. So, engine is coming out so I can fix that. But, when it goes back in, this is going to happen:
He's a member on here and local to me. Should go right off his and bolt onto mine. I'm selling my heads, cam, intake, throttle body and nitrous system. Installing the 317 heads I took off previously and reinstalling the shaved truck intake. I'm going to install a very mild turbo cam and change the 4.30 gears to 3.08 or similar. Should make 600 to the tire, which is more than the 550 I made with the nitrous, and drive better. Excited...but a lot of work ahead.
He's a member on here and local to me. Should go right off his and bolt onto mine. I'm selling my heads, cam, intake, throttle body and nitrous system. Installing the 317 heads I took off previously and reinstalling the shaved truck intake. I'm going to install a very mild turbo cam and change the 4.30 gears to 3.08 or similar. Should make 600 to the tire, which is more than the 550 I made with the nitrous, and drive better. Excited...but a lot of work ahead.
#84
Small update. Lost oil pressure on the freeway last month. Cut the filter apart and it was filled with bearing material. Yanked the motor on Monday to get it rebuilt. Turbo isn't going the happen afterall...because I got a deal on a new 408 I couldn't refuse. Grabbed a set of 2" hedman long tube swap headers to replace the hacked up f-body 1-3/4 Pacesetters, a Circle-D billet single clutch 3800 stall and a off the shelf Comp Cam (sorry Martin, I ran out of money!) to go with the 408.
I'll reuse the current top-end. With -15cc pistons, it's about 10.8:1 compression. Plan to up the Proton system to the max 250 shot too. All of my friends are yelling at me to get a cage now. And I'm going to have to get taller rear gears. Maybe 3.90 instead of the 4.30s.
I'll reuse the current top-end. With -15cc pistons, it's about 10.8:1 compression. Plan to up the Proton system to the max 250 shot too. All of my friends are yelling at me to get a cage now. And I'm going to have to get taller rear gears. Maybe 3.90 instead of the 4.30s.
#85
They make one for a 4l80e application. They also sell the frame extension needed for early cars like mine. They sell them on ebay under the seller name pitqueen. Here is an older auction, looks like they haven't listed any for a while though. G Body Malibu Lightweight Crossmember and Extension | eBay
#87
I ordered mine directly from his website and I didn't get any hardware. I will find some and get the hammer ready.
Last edited by Garrett1982; 02-21-2016 at 03:26 PM. Reason: Mispelling
#89
I've had a couple guys ask me about the throttle bracket I'm using. It's a GM Part, stock truck throttle cable bracket. I went with it because I plan on installing cruise control cable too. GM #89017380
It's part 11 in the diagram. http://www.tonkinonlineparts.com/sho...ssembly=806423[/QUOTE][/QUOTE]
Attachment 721621
It's part 11 in the diagram. http://www.tonkinonlineparts.com/sho...ssembly=806423[/QUOTE][/QUOTE]
Attachment 721621
#90
The tear down continues.
Rod bearings were fine.
Tops of the pistons and the valves looked good too.
Pan had a good collection of junk in it.
Found pieces of valve spring from a previous ooopsie.
All of the lifters looked good too. The search continues for the source of my oil pressure loss. Not that it matters, building a 375 anyway.
Rod bearings were fine.
Tops of the pistons and the valves looked good too.
Pan had a good collection of junk in it.
Found pieces of valve spring from a previous ooopsie.
All of the lifters looked good too. The search continues for the source of my oil pressure loss. Not that it matters, building a 375 anyway.
Last edited by 1970camaroRS; 05-06-2016 at 11:14 PM.
#91
Found where my oil pressure went.
Stupid cam bearings. No one likes you.
In other news, I got a deal on a set of 4.060 flat top forged pistons for stock stroke and stock rods. I'm going to drop off the engine at the machine shop next week and have it bored, then throw it all back together with a big Tick cam and call it a day. So, 375, not 408.
Stupid cam bearings. No one likes you.
In other news, I got a deal on a set of 4.060 flat top forged pistons for stock stroke and stock rods. I'm going to drop off the engine at the machine shop next week and have it bored, then throw it all back together with a big Tick cam and call it a day. So, 375, not 408.
Last edited by 1970camaroRS; 05-06-2016 at 11:12 PM.
#92
Here's what the plan is:
Bore: 4.060
Stroke: 3.622
Gasket bore: 4.1
Gasket thickness: .051
Piston dish: 4cc
Piston out: .016
Combustion Chamber: 60cc
Quench: .035
Compression ratio: 11.7:1
Displacement: 375
Cam: 239/244, .635”/.610”, LSA111+2
Reuse my PRC 5.3L Heads.
Dynamic Comp: 8.7x
Should rip pretty hard.
Bore: 4.060
Stroke: 3.622
Gasket bore: 4.1
Gasket thickness: .051
Piston dish: 4cc
Piston out: .016
Combustion Chamber: 60cc
Quench: .035
Compression ratio: 11.7:1
Displacement: 375
Cam: 239/244, .635”/.610”, LSA111+2
Reuse my PRC 5.3L Heads.
Dynamic Comp: 8.7x
Should rip pretty hard.
Last edited by 1970camaroRS; 05-01-2016 at 11:23 PM.
#94
#95
Packed everything into the back of my wife's old Scion Tc. The Cutlass is my daily, so this has been my backup car while the engine is out. It sucks. Anyway, turns out the Scion, even on lowering springs, makes a decent shop truck. Off to the machine shop it all goes. In about 4-5 weeks I will be the proud father of a fresh 375" shortblock.
Last edited by 1970camaroRS; 05-06-2016 at 11:12 PM.
#96
#97
One of the big corners I'm cutting in my rebuild is that I'm reusing my stock rods with ARP bolts. Not the smartest for a 7500rpm motor, but money ran out. And pressed forged rods at stock length are hard to come by. A few people, including the machine shop owner, have given me crap about this choice but the options I found are all $600 or more. I happened to find some unexpected money, not a lot, but enough. So, I went looking for "ls1 forged pressed rods" in Google and this SCAT rods popped up. They're 6.100 instead of 6.098 but my pistons will work with both lengths as long as they're pressed. Decking the block for .040 quench with a .051 gasket when cold anyway, so we're not really hurting anything here. Really surprised at the price and reviews are mostly positive. Should balance out fine, but stronger than the stockers and work with my new pistons. Pretty happy to cross one worry off my list.
http://www.summitracing.com/parts/sc...944p/overview/
http://www.summitracing.com/parts/sc...944p/overview/
#99
Scion Tc shop truck completes another mission.
So fresh, so clean.
Almost a shame to cover this up.
Now I just have to put in the cam, oil pump, lifters, heads, oil pan, front cover, rear cover, flex plate, motor mounts, drop the engine in the car, install intake manifold, water pump, ignition coils, radiator, hoses, intake tube, test fit headers, weld o2 bungs, weld v-band (or slip fits) and modify existing exhaust to fit and paint the headers. Plus a few misc electrical tid-bits. Oh, and the adjustable lower control arms, And rewire nitrous system, install purge and bottle heater. Then tune the whole thing. Just a short list.
At least that pretty little billet circle-d is going to be put to use soon.
So fresh, so clean.
Almost a shame to cover this up.
Now I just have to put in the cam, oil pump, lifters, heads, oil pan, front cover, rear cover, flex plate, motor mounts, drop the engine in the car, install intake manifold, water pump, ignition coils, radiator, hoses, intake tube, test fit headers, weld o2 bungs, weld v-band (or slip fits) and modify existing exhaust to fit and paint the headers. Plus a few misc electrical tid-bits. Oh, and the adjustable lower control arms, And rewire nitrous system, install purge and bottle heater. Then tune the whole thing. Just a short list.
At least that pretty little billet circle-d is going to be put to use soon.
#100
Was doing some final math and detail work before getting to work assembling the rest of the motor. I ended up with the pistons .004 out and was hoping for .010 to .015. With the .051 head gasket that gives me 11.35:1 compression and .047 piston to head clearance. Not enough compression, and too little quench. If I got a .040 gasket I would end up with a nice tight .035 quench but 11.7:1 compression which is pushing it just too far. A .045 gasket, however, gives me 11.52:1 compression and puts me on the high end of the quench target at .041. Downside is that the only gasket that thick I could find that was in stock are 4.130 bore, which isn't bad, but bigger than required for my 4.060 bore and PRC 5.3L heads.