LT1 swap AGAIN! Engine differences? Help needed.

[gvincent]

Hi,

I was almost done with my 76 280Z 95LT1/T56 swap, I had some wiring issues to resolve and I thought I was good to go.

My 95 LT1 was from a TransAm with 80K and sound and ran fine when I pulled it last August. I got it to fire up in January and have been completing the rest of the install ocassionally starting it up and doing the TunerCat deletes etc.

I was having problems getting the stock gauges to work but have an AutoMeter Tach and Speedo, The SES light is on, no codes present but a single speed fan.

I had fuel pump issues with the stock tired fuel pump and put in an Aermotive AFPR and a Mallory Fuel pump. I recently started it up to hear an engine knock I think it might of spun a bearing, how is this possible????

Anyway for fear of causing any more damage I have available a LT1 from a 1995 Cadillac with 80K also. I am thinking I will swap motors so I can at least enjoy part of the summer driving this car while I rebuild the other LT1 with some goodies next winter.

So the obvious:

1. I'll need to swap the flywheel from the TransAm LT1 to the Caddie motor.

2. Swap my CAI system over

3. Will my Sanderson Block Hugger headers from JTR work, they are for the angle plug aluminum heads aren't the iron heads straight plug? Do I have to swap heads, any cheaper ideas?

4. swap all my front mounted accessories and mounts over.

Is there anything else I am missing?

 

God I hate to have to pull this out, It was almost done.

I just want to drive this car for a little while!

 

Anybody nearby want to help?

I am still going to have to figure out the tune and SES light.

More to follow.

Greg

Bumming in MA

[gvincent]

Wheelman and other Iron Head Caprice, Buick Caddie LT1 guys, Did you use a different header than the Sanderson "D" port header for angled plug heads?

The Iron head is a straight plug "D" port head?

I may have to swap motors and rather not have to swap the heads also.

Thanks,

Greg

[gvincent]

Picked up the Iron Head LT1 last night, it is definately a straight plug head.

At first look I don't think my Sanderson angle plug headers on my Aluminum LT1 heads will work on these guys. Anybody tried this?

Anybody have a used set of Blockhugger Sanderson LT1 straight plug headers they want to sell cheaply????

Greg

[wheelman]

I used Headman Tight Tube headers. They hug the block very close and have a flat collector that positions the primary tubes parallel to each other rather than forming a square. I have no problen getting at the plugs and they give a little more clearance for the steering shaft.

 

The spun bearing was probably caused by low oil pressure and high rpms at some point. I bet it was marginal when you bought the donor car and finally let go when you were messing with it.

 

Wheelman

[gvincent]

I installed a new mellings HV oil pump and metal pump shaft and coupler and an 8 quart Hamburger oil pan and pick-up tube and screen on just before I installed the motor in the car. The motor only had 80K on it and sounded just fine when I picked it up and drove the wrecked Firebird on and off the trailer before I pulled the motor. The engine did sit from late August until January when I first got it started. I currently have 60 PSI oil pressure reading on the mechanical gauge even with the knock. I hooked up to the gauge to the oil port just above the oil filter. I just don't understand the knock, I wish somebody was near by that can identify the sound better than I can. I don't have a camcorder or I would of recorded it and posted it to get some opinions on the sound. Maybe I can bring my sons iBook laptop out and record it.., it has a built in mic and camera...HMMMM

Greg

[gvincent]

Well a friend came by and took a listen, It started right up but the knock was there and the motor was running real rough, missing and like it was running on 6 cylinders. I am going to take the motor and tranny out ((, no more messing around, I will start to prep the Iron head LT1 as well.

Crap! I am bumming!

Looks like my first attempt at a rebuild this winter.

I will start looking at Grumpy's list of suggested reading material.

I'll try and call JTR or Sanderson to see if my angle plug head headers will fit the Iron head straight plug heads.

[gvincent]

Checked with the tech guys at Sanderson, The CC-5 headers with 1-5/8" pipes and "D" port will fit the Iron Head LT1 motor, the outside plugs will be a little close they said because of the 1-5/8" pipes but should be ok. If you have the 1-1/2" pipes there is plenty of room they said.

So I am going to swap the headers over when I pull the LT1.

Greg

[Guest NoBars]

I ate a drive gear in my LT1 swapped into a full size chevy shortbed with a HV melling, come to find it is a big no-no. "What is that tapping noise?" after swapping the mains and rod bearings (in the truck) I use the stock pump.

[gvincent]

So I should of stuck with the stock pump, a solid pump shaft and sleeve to upgrade from the nylon sleeve and of course keep the Hamburger pick up tube for the 8 quart pan.

Curious as to why was the HV pump a big no no???

I am almost done prepping the stock iron head Caddy LT1 for the swap

I am not going to swap over any of the parts from the Trans AM LT!

[gvincent]

Actually Grumpy posted one of his excellent write-ups on oil pumps in this thread here:

http://forums.hybridz.org/showthread.php?t=137375

You want to read his post #2

I read it and need to read it about 5 more times before It starts to sink in and I can grasp all the great info in that thread.

I am wondering if my pickup tube was too close to the deep 8 quart Hamburger pan? but I had checked with the guys on the right Melling pump to use before I swapped out the old pump, Oh well I will use Grumpy's method to check this once I rebuild the motor before I put the pan back on.

Greg

[grumpyvette]

THE KNOCK can easily be due to poor oil flow to the rockers or CLEARANCE ISSUES that were not properly dealt with durring the assembly process,and you would sure not be the first guy with a loose flexplate or flywheel or a busted valve spring or badly adjusted rocker, a rod hitting the block, or valve hitting a piston, due to faulty assembly or clearancing ,KNOCKING in the engine is not necessarily limited to bad rod bearings

STEP ONE either do a compression test, and diagnose the source or pull the engine apart and check, running it will only cause more problems

TALLER PUMP,gears MAKE the pump body sit lower in the oil pan, if the stock pick-up was 3/8" from the pan floor, swapping to the longer pump body places it about ON the pan floor and it WILL severly restrict oil flow into the pump, and if you don,t change the pick-up that means the pan floor to pick-up clearance is MARGINAL to critical if the pumps changed from the standard to the high volume oil pump

 

high volume oil pumps SHOULD NOT be used without the other matched components, a matching high volume baffled oil pan, (Id suggest a minimum of 7 qts) and windage screen (like the moroso design) that forces oil back into the sump,and the necessary block clearancing necessary to allow the oil to drain efficently back to the sump

BUT if the full system components are used and the clearances verified IVE NEVER seen any loss of oil control or pressure.....naturally if all the factors are not met, problems might occure,if your engines NOT set up to USE the extra oil flow rates theres not much advantage to trying to supply extra oil, but that doesn,t mean the high volume oil pump doesn,t have a function if the engines designed to supply and control the extra oil flow that can be very beneficial if its used to supply extra oil flow rates to high stress areas, like grouving the lifter bores to supply pressurized oil to the cam lobes and drilling the front oil passage plugs to supply oil to the cam drive,slightly larger bearing clearances (a extra half a thousandth in some cases) to provide extra cooling to the bearings, and grouving the distrib to spray oil dirrectly onto the cam gear

 

[gvincent]

Thanks Grumpy,

The engine that has the knock was a strictly a stock LT1 with 80K miles form a 95 Trans Am. I dropped the stock oil pan and removed the crank bolts/studs that held the stock tray in place and replaced them with factory bolts and torqued them to spec. I installed the Mellings M55HV oil pump and solid shaft and metal collar. I then installed the oil pick-up that came with the Trans Dapt 8 quart Hamburger oil pan #1098. The pan has a windage tray welded to it and baffle doors. I assumed that the Mellings M55HV pump was correct as that was what Trans Dapt had reccommended to me.

The knock wasn't there right away and developed over time, since it hasn't been driven other than to drive it on and off a trailer the rest of the time was simply starting it and running it to see what TunerCAT was reading as we deleted EGR, VATS, and other things, It did have some problem with cooling and I wonder if I overheated it as I was trying to get gauges to work.

I have the other engine almost prepped to swap it out but ran into some OptiSpark problems....Long story, tiny little Torx bolts break while removing cap and rotor, drill bit breaks...you get the picture, looks like I am going to have to use my spare brand new Opti-Spark distributor on this motor!

ARGHH!

Anybody want to trade for 2 LT1 motors with a ton of parts and accessories for a Old School 400SBC?