ndndndnd

Well, I guess the previous owner didn't do a good job of rebuildling this 305.

Second drive of the year, and it suffered a catastrophic loss of oil and immediately started knocking. Of course, being rather naive to total engine failure, I decided the ticking sound was an exhaust leak and drove the next couple of miles back home, not noticing the oil gauge sat on zero until I got to the driveway.

Ugh.

I've been quoted big money to strip down and repair the engine (note I'm in the UK...) so I'm considering engine replacement possibilities. I did wonder if I could pull off the sump and replace any loose rod bearings in-situ, but further research suggests this isn't going to go well.

I'd like to keep my E4ME.

Options:
1) GM 350/290 - drop in, stick E4ME on top (available in the UK, but stock is limited)

2) Blueprint BT3503CT1, stick L69 intake and E4ME on top (available in the UK) this would be a hike in power to 373bhp, and need a new flywheel for one-piece RMS.

3) Procure 350 short block from somewhere, stick L69 heads, intake and E4ME on top. (available on eBay...)

Car is running a NWC T5, but it won't be wearing slicks or power shifting on quarter-miles, so I'm hoping it can take a bump in power.

Kinda new engine specifications (cam durations, lift, etc. etc.), and rather gutted as I really thought this year would be the year by car was finally a turn-key example... and it pretty much did the worst thing it could. With kids and my business, both time and money are a bit short, and I really hoped the car was finally one I could just enjoy!

Open to any suggestions!

Cheers,

ND

NoEmissions84TA

iTrader: (1)

My , at this point forget about anything 305 and find a complete running L31R Vortec engine from a 1996-2000 Chevy/GMC truck.
It's a 350 with roller camshaft and Vortec heads. Then you can continue with your plan to keep the E4ME carb. You will need a different intake that matches the Vortec heads and the carb will need some tuning/recalibrating.
Actually GM did sell this package years ago to do this exact swap - ZZ4. The package came with everything to put a ZZ4 350 into these cars and keep it emissions legal. I am guessing that you don't have to worry about emissions in the UK.
Do a search for ZZ4 conversion. And reads these threads below:
https://www.thirdgen.org/forums/engi...ate-motor.html
https://www.thirdgen.org/forums/tech...0-cam-l31.html

ndndndnd

Hi, thanks for the suggestion. Unfortunately, getting access to an engine from a truck like that is trickier in the UK. Funnily enough, I think someone is selling an engine like that on Ebay at the moment, however he's asking as much as a crate engine for it!

A known-good supplier of American parts in the UK is selling a 5.3l LM7 engine for a reasonable sum, but a quick search on here suggests it's not a straightforward connection to a T5 - new bellhousing required and the rotation in the transmission is different, leading to issues with torque arm etc...

As for sticking the E4ME on that blueprint engine, will the carb take the vacuum and power demands without being physically modified? By tuned do you just mean adjust the idle screws and IAB as necessary, and the computer as it stands will compensate? I accept I might have to modify the secondaries, but I assume that'll just be adjusting the tension on the AV doors and different rods/hangers?

I know I'd need a new flywheel and intake for that blueprint engine, which will add another £500 to the project, but it is proper horsepower, which is tempting...

midias

The LM7 is a LS bases motor. If you are looking for a newer motor that will bolt in you want a L31 but you will need a new intake manifold

TransamGTA350

iTrader: (2)

I would do the GM 350/290 crate motor if you can get it. Everything from your 85' 305 will bolt right up and it's a new GM motor. Some tuning of the Quadrajet secondary metering rods and a 350 knock sensor and you'll be good to go.

ndndndnd

Annoyingly, I can get hold of a 350/290 in the UK, but only in deluxe form with an intake (which might be handy) plus some blingy valve covers, air intake and timing cover (which aren't much use). Unfortunately it's £600 more expensive, pushing it up to the price of the 373bhp Blueprint long block! Trying to assess if it's worth the extra just to have it sooner, but then I don't know how quickly I'll have the time to swap it in the car anyway. Might just put my name down for a short block and bide my time...

One thing that does worry me about the GM motor is bedding in the cam. My car's never started that well after being sat dormant and it seems a good start is crucial to bedding the cam in properly. How readily will the car start the first time after swapping the carb etc. across? The installation instructions then suggest a series of rather-impractical highway pulls... Unfortunately my car's annual inspection (MOT test) is due to expire next week, so it'll have to be bedded in static regardless.

Any advice?!

NoEmissions84TA

iTrader: (1)

Yep, do this if you can (watch the videos): https://www.thirdgen.org/forums/carb...ml#post6421650

ndndndnd

Thanks - I assume you're referring in that video to using a separate supply of petrol from a bottle to prime the carb? I hope you're not referring to drilling out all the idle tubes as that's way above my pay grade!

I've been reading more about the 350/290. How good an engine is it? Sofakingdom on here seems particularly dismissive of it, and he seems to think it'll be down on power even compared to the L69 it'll replace.

Post No. 16 on here: https://www.thirdgen.org/forums/engi...rformance.html

It'll be installed without a cat, with tubular headers and with the L69 intake. Will that be enough to let the motor breathe? I'll admit dropping to an 8.0:1 compression ratio is a bit depressing.

It would be interesting to see some chassis dyno figures, but despite this engine being available for decades I can't seem to find someone who's stuck one on a dyno to see what it can actually make at the wheels!

NoEmissions84TA

iTrader: (1)

Yes, petrol from a bottle.
I guess availability of parts is going to have a huge influence on your decisions going forward.

midias

Normally I would agree don't get the 290/350 but due to parts availability in your region if that is what you can get go for it. Your can always do a head swap later and gain some compression.

five7kid

iTrader: (14)

The ZZ4 wasn't a Vortec engine. It was a 350 1-piece RMS roller lifter shortblock with 113 aluminum heads on it and a "ZZ4" spec roller cam.

Otherwise, the L31 swap isn't a bad idea. The Vortec heads don't have the exhaust crossover ports to feed the EGR (neither did the 113s), otherwise nothing to keep the E4ME from doing its thing.

TransamGTA350

iTrader: (2)

The Vortec L31 would work, but there's just more parts to change for compatibility. The parts that come to mind are:
-Intake manifold
-Flywheel or flex plate
-Disable EGR (that's not a big deal as long as there is no emissions requirement)
-Distributor gear
-Add electric fuel pump (L31 doesn't have mechanical fuel pump provisions)
-Passenger rear exhaust manifold bolt can't be used, but not an issue if headers are used
-Probably some other minor bits that I'm not thinking of

The 350/290 is more plug and play with what's in there now. Both are reasonable choices, depending on availability and price.

ndndndnd

Thanks for the shopping list! Really useful - most I was aware of, but it's little 'gotchas' like the distributor gear that I had no idea about. Would this go for all the single-piece RMS blocks, like the Blueprint motor I have my eye on? https://roadcraftuk.co.uk/index.php?...product_id=778

Similarly the fuel pump. Eeesh: http://67-72chevytrucks.com/vboard/s...d.php?t=709837 sounds like I'd need to swap the cam and drill the block to allow for a mech pump!! My car's one of the ones that had two pumps, and the in-tank one is dead... maybe I could stick an appropriate electric one in there instead? More complication....

I was going to ask about this engine: https://www.gmperformancemotor.com/parts/12691673.html a crate L31 apparently on at a good price. Only rated at 250bhp, but would it run stronger with headers and a good exhaust? Cam looks mild? According to my part supplier, I've two weeks before the next shipment is loaded and I needed to have my name on a motor by then! I could theoretically ask for one of these instead of the 350/290, which are apparently delayed until June and might miss that next boat.

I'm still doing a bit of research to ensure I'm going the right direction, and the 350/290 motor is still coming out on top, despite the crappy compression ratio and delayed delivery. I guess the tall lift on the flat-tappet cams will mean a thirsty car and reduced valvetrain life? I've heard that higher compression and a milder cam is preferable.

The big advantage of that BluePrint motor: https://roadcraftuk.co.uk/index.php?...product_id=778 is that it's available NOW. I did notice the cam LSA is only 110°, would this be too small a separation for my E4ME?

Sorry, this has been a bit of a stream of consciousness during a break at work! That earlier-block 350/290 really does look a lot simpler when you take into account the intake, mech pump, dizzy gear etc... I guess these complexities would also go for the later L98 350 roller block thirdgens had from 87 onward?

My dream: a two piece RMS block, 64cc cylinder heads, roller cam, mech pump, stock L69 intake on top... could even go flat tappet if the compression is there... 300bhp?

midias

The blueprint engine looks nice and upgrading to a roller is a huge win. The CC carb should not care about the 110lsa. Roller cams want a different distributor gear

ndndndnd

I know, it's tempting isn't it? Only another £600 or so for the shortblock, plus about £750 of extra gubbins needed. Would my NWC T-5 survive...?

Good to know the LSA isn't an issue either - I assume that degree of LSA will result in a reduced manifold vacuum at idle over 114-117, though? Do I just back out the idle mixture screws to compensate?

Can I just fit a different dizzy gear to my existing dizzy?

Can anyone recommend a Vortec to spreadbore intake? The only one I've found is a Procomp Cylone, which I can get shipped over. Seems to be low-rise, not too expensive and should be ok?

Also, the low-pressure in-tank pump in the L69 apparently runs at about 5 psi. Could I really just run the Q-jet directly off that (with return line obviously) and dispense with the mechanical pump altogether, or would it be too risky running a pump to a carb without a regulator?

Awesome help all you guys, with a fair wind I might even get this thing back on the road this summer...

midias

NO idea about the pump but edelbrock 2116 should work for the intake

midias

NO idea about the pump but edelbrock 2116 should work for the intake

five7kid

iTrader: (14)

The in-tank pump on the L69 is just a pusher pump. The mechanical pump on the engine is still required to get good fuel supply up to the carb.

But, you could remove the L69 pump and put in a true in-tank like the TPI pump or an aftermarket like the Walbro 255, with a return-type regulator, and that would work. The later EFI small block Chevys often don't have the provisions machined for the mechanical pump, so you might have to do something, anyway.

Scott's 83' Z

I did see a pre-1986 350 on roadcraft’s website for £1,989.00. It appears that could be a viable option and a platform to improve at a later date. It is advertised at approx 250hp with a edelbrock Intake and carb. That would not push your t5 too hard and you could use your L69 heads to increase the compression again upgrade and not break the bank doing so....

ndndndnd

I did spot that - I'm a bit unsure going for the 350/260 engine. I believe it's the same as the 350/195, just quoted by its gross power output? Just worried it might be a bit disappointing! I presume it'll make similar power to my L69, just use more fuel in the process... I have read of other people swapping the milder 260 cam into the 290, as the milder cam is more suited to the low-compression heads - although I guess this is because the torquey-er output is better suited to Autos, which should be less of an issue with my T5. I don't mind a bit of heel n' toe action.

I did read about putting the L69 heads onto a 350 - I think the result is more low-down torque, but the smaller valves become a limiting factor. Plus how much swarf is likely to be in there....? Will I be able to re-use the 350/290's cams and pushrods etc?

http://www.montecarloss.com/communit...&Number=400358

Regarding the fuel pump, apparently people have used a tank-mounted low pressure pump in conjunction with a carb 'without problems' but it seems the fuel pressure can fluctuate under braking and acceleration at that low pressure, just due to the weight of fuel in that long line!

https://www.thirdgen.org/forums/carb...-electric.html

It seems it's possible, but running a higher pressure with a regulator is much more robust. I don't particularly want the carb suddenly flooding if I need to do an emergency stop!

Ugh.. I need to make some choices and fry my credit card before the summer's gone...!

ndndndnd

Hmmm... would I be right in thinking a crate L31-R would make the same flywheel horsepower as the crate GM 350/290?

Does anyone know how the two engines will compare in driveability? I'm assuming the L31 will have more low-down torque and a similar top end, with a higher redline?

Oh... and can I re-use my Gen I water pump... or do all the Vortec head/one-piece seal blocks use reverse rotation?

TransamGTA350

iTrader: (2)

I would imagine both motors will be around 250 net horsepower installed in the car. and will probably have similar power curves. Neither will be a screamer, but the L31 is probably more torque biased.

The standard rotation v-belt water pump will work with the L31.

ndndndnd

Awesome, thanks - I just spotted something about reverse-rotation water pumps and wasn't sure if it applied to all Vortec-headed engines.

Just trying to get prices for an L31 to see if it compare favourably with the 350/290... although looking at the options this is still looking the best bet. If only they were in stock!

midias

The L31 will have more low end higher compression and most importantly a roller cam also 4 bolt mains

midias

The rotation direction is based on your accessories. If your have a serpentine belt routed so the pump spins in reverse you need that kind of pump. if you are reusing your stock stuff you need a stock pump

ndndndnd

Thanks for clarifying that - sounds so simple when explained!

Regarding the L31 and Vortec heads, I've read of people of people having to cut and re-weld their y-pipes to suit the slightly re-positioned exhaust ports on the later head. Is this really a thing? This would kill swapping to a later engine stone-dead for me, as cutting and re-welding stuff is up and beyond my abilities. I could get the exhaust shop who made up my y-pipe to make the adjustment, but it'll be another chunk of cost and complexity.

ndndndnd

Can anyone confirm the thing about the Vortecs having differently-positioned exhaust ports, meaning I'll need to cut and weld my y-pipe?

It doesn't sound right, but... is it a thing?

midias

I don't know about the factory y pipe but I use the same headers and y-pipe on both vortec and non-vortec heads on two different sets of headers

TransamGTA350

iTrader: (2)

The GM Fast Burn Heads have a raised exhaust port. I don't believe the standard Vortec heads are raised. However, the Vortec heads don't have the 2nd threaded exhaust bolt hole on the passenger rear, so you will not be able to install the rearmost exhaust manifold bolt on the passenger side.

dmccain

iTrader: (2)

I tried using the factory manifolds on Vortecs before even tried an adapter they had at the time and it leaked from day #1. Went to headers and no problems. This was on my last Trans Am years ago.

dmccain

iTrader: (2)

About the 290hp Goodwrench.. No way they make that much HP I just don't believe it. 8:5 compression, 76cc heads.. I drove one in a friends C10 recently and it was no stronger than a 205HP L05. Not one bit. The Vortec will easily make 300 with just a lil cam. Makes way more than the 250 its rated running the **** poor spider injection I can tell you that.

ndndndnd

Ok, that figures - it doesn't really make sense for them to be in different locations.

I know what you mean about the 350/290 crate. It's the easy, cheapest answer as it'll drop in, but I'm nervous I'll be disappointed. Should still be a good 70-80bhp up on what's in there at the moment though, as I'm running tubular headers and no cat, right?

Scott's 83' Z

The reason I mentioned it was two reasons. First, it would be a platform to build off of. You get a 350 which will make 300 ft lbs of torque versus the 240 lbs of your dead L69. It will be an improvement from the old motor. You can upgrade the camshaft, heads before you install and your intake and carb will work. The only real limit is your budget. You would the least amount of work to get your car on road.

Second, the T5 in your car is only rated to about 285 ft pounds. It will fail at some point behind a 350 even if you drive like you are 75 years old. Do you want to put too much motor in front of that tranny and risk it failing on you??? I have the same drivetrain combo and have had trouble with my tranny. I bought a used T56 to install in my car just because I know my T5 isn’t going to last.

Hope whatever you decide works out for ya!!!

ndndndnd

No, those are good points! For me I guess it's a little of the unknown. I was pondering that it's little daft looking for a 'better' engine when this car is rarely going to see full throttle anyway. As for installing camshaft and heads, I'm already testing my limits by doing an engine swap in the first place - I really need something that's as plug-and-play as possible, and it seems a little counterintuitive to buy components I'm immediately going to replace.

The limitations of my T5 are also in the back of my mind! Mine's also a NWC, so I think the torque limit might even be a little lower. There are a few stories on here of people running higher-powered engines behind them without problems and, like I say, I'm not going to be doing quarter miles in my car, so maybe it'll be ok? I've also read that a Pro 5.0 shifter can help the gearbox last longer by making the shifts more positive, which sounds a bit daft but it's a good excuse to get a Pro 5.0!

At the moment, my limitation is availability. The crate motors just aren't available and it'll be a few months before they're in the UK. The couple of importers I've spoken to won't commit and prices seem to have risen. I'm sitting on my hands, looking at options. I might re-open negotiations with my local shop - they've just put a rebuilt vortec engine up at a not-silly price, so I might ask how much it might cost to build up a pre-86 style long block for me. I'm browsing through JEGS and ATK crate motors too, but I'm not sure I'm happy taking the risk when I'm not even in the same country as their warranty company!

thainglo

iTrader: (1)

I am in pretty much the same boat. The 350 in my 85 Trans Am has a cracked block. Not horrible yet as on my a small a punt of seepage, but on borrowed time. I sourced a roller block 350 this past weekend and tearing it down for machine work. I also have a NWC T5 that makes the car a lot of fun to drive, along with 3.70 rear gears. Trying to figure out a cam and head combo that will have good road manners without destroying the transmission. Not a racer, just a cruiser. And wanting to keep it TPI, so that were a wrinkle.

Good luck in your engine hunt! Here in the states, crate engine builders are 3 months backordered, at least when I checked last month. One guy told me shortage of blocks, another one said historically high demand.
​​​​​

ndndndnd

Hey guys... Late night googling.

Volvo Penta AQ271. There's a refurb'd longblock available in the UK for reasonable money. I might hit the guy up to confirm specs but...

... am I mad?

I know I need to be aware of reverse rotation, not sure if mechanical fuel pump is provided for... Don't know about cam specs either. Will a marine engine simply not be set up for car use in terms of how it makes power and torque?

TransamGTA350

iTrader: (2)

Might be a viable option as long as it’s not reverse rotation. Marine engines have brass freeze plugs and head gaskets designed for fresh water cooling. Otherwise, they are pretty much the same internally as their street versions. Marine camshafts are typically not much different than a standard truck camshaft. I would also want to know the previous life of that long block. If it was always in a marine application and lived in salt water, I would pass on it. I have seen old salt water cooled marine SBC motors rot through the water jacket and make a milkshake out of the engine oil. If it was a freshwater trailer boat, or more likely it was a truck engine that was remanufactured and “marinized”, then that’s fine.

Still need to verify type of heads (86’-earlier, 87’-95 or Vortec), and 1-piece vs 2-piece rear main seal. I don’t know the specifics about that Volvo penta model number other than it’s a 275hp 350, so it’s going to be equivalent to a run of the mill 350.

ndndndnd

A quick bit of googling suggests it's unlikely that a modern marine engine would run reverse rotation, as apparently they now do it in the final drive when coupling engines together. Also, it seems there aren't great differences between marine and automotive head gaskets - although this might depend on how the engine has been previously used. You're quite right about checking the provenance of the engine - I can imagine salt water will have played hell with the cooling galleries. In the UK, I think it's unlikely that it's a truck engine that's been marinized, as they simply aren't that common - plus it is advertised as a Volvo Penta, so I guess it's more likely to have been used for marine previously. How truthful is an eBay seller to be with it's past usage? "Of course it was never used in salt water, sir!"

Hmm...

Looks like Scoggy Dickin might actually have 350 GM crates back in stock. I think I'd better just see if I can sort out a container for one. I've noticed some very strong prices for third gens in the UK now... makes me feel a bit better about spending a chunk of cash on mine. Plus, I guess an official GM performance motor might be good for the car's resale value....?

ndndndnd

OKAY.

Right, I can get a 350/260 engine in the UK for a reasonable price, so I'm going for it. Just working out where to get it delivered and I'll hit 'buy' on it.

Not the greatest engine but it should do. I may roll up my sleeves and, to quote Shakespeare, "pin my courage to the sticking place and shove a cam in it".

Can anyone recommend a cam? I'll take top end response over low-down torque (I think...). I've sort-of read that a cam with better dynamic compression ratio (???) will work better with the low-compression heads, building better intake vacuum pressure.

I've noticed Pace Performance do this version of the GMP crate: https://paceperformance.com/Small-Bl...681429-KX.html, which comes with a cam with these specs: https://www.competitionproducts.com/.../#.YNg9ZNVKjAQ (not sure if it's actually an Elgin cam, a google just brought up this result).
Pace Performance reckon this cam with a ZZ4 intake is good for 325(gross)hp... Not sure how far my L69 intake is from a ZZ4...
https://paceperformance.com/Small-Bl...420194-KZ.html

Cam Lift: .443” Intake / .465” exhaust
Cam Duration @ .050”: 214 deg. Intake / 224 deg. Exhaust
Lobe Separation: 112 Degree

The GM 350/290 comes with this:
Cam Lift: .450” Intake / .460” exhaust
Cam Duration @ .050”: 222deg. Intake / 222 deg. Exhaust
Lobe Separation: 112 Degree

Does that spec sound like a good place to go? Fitting a cam is easy, right...?

Cheers!

midias

A Cam swap is not too hard when the engine out. You do need to make sure to install correctly but access makes it a lot easier.

Scott's 83' Z

[QUOTE=ndndndnd;6431417]OKAY.

Right, I can get a 350/260 engine in the UK for a reasonable price, so I'm going for it. Just working out where to get it delivered and I'll hit 'buy' on it.

Not the greatest engine but it should do. I may roll up my sleeves and, to quote Shakespeare, "pin my courage to the sticking place and shove a cam in it".

Can anyone recommend a cam? I'll take top end response over low-down torque (I think...). I've sort-of read that a cam with better dynamic compression ratio (???) will work better with the low-compression heads, building better intake vacuum pressure.

I've noticed Pace Performance do this version of the GMP crate: https://paceperformance.com/Small-Bl...681429-KX.html, which comes with a cam with these specs: https://www.competitionproducts.com/.../#.YNg9ZNVKjAQ (not sure if it's actually an Elgin cam, a google just brought up this result).
Pace Performance reckon this cam with a ZZ4 intake is good for 325(gross)hp... Not sure how far my L69 intake is from a ZZ4...
https://paceperformance.com/Small-Bl...420194-KZ.html

Cam Lift: .443” Intake / .465” exhaust
Cam Duration @ .050”: 214 deg. Intake / 224 deg. Exhaust
Lobe Separation: 112 Degree

The GM 350/290 comes with this:
Cam Lift: .450” Intake / .460” exhaust
Cam Duration @ .050”: 222deg. Intake / 222 deg. Exhaust
Lobe Separation: 112 Degree

Does that spec sound like a good place to go? Fitting a cam is easy, right...?

Cheers![/QUOTE

Or……. Get the cam specs from motor in question and see if a 1.52 or 1.6 ratio rocker arms arms will get the lift into the ballpark of the cams you are looking at. I will hazard a guess that the 1.52 will be close. You would need 16 new rocker arms, a adjustable push rod to measure for the correct length push rods and order 16 new push rods. That would be less work than a new camshaft, especially if you are not comfortable installing a cam.

Just a thought….

ndndndnd

And that's a good thought - thanks, I'll look into it.

Unfortunately the supplier I thought I'd found for an engine in the UK turned out not to have engines, jacked up the price and started messing about... so back to square one.

Starting to wonder if I should mothball the car until next year - perhaps when the pandemic has started to calm down and all the furloughed workers go back to their tools and desks, then supply of engines will increase, demand will reduce, prices might start to correct themselves a little and engines actually start becoming more available!

Irritating time for my car to break!

ndndndnd

350/290 crate motor purchased... arriving next week. I suspect a lot of random questions will follow.

Do I need a melonized distributor gear? GM performance website suggests a melonized gear is needed with all steel camshafts. Will my L69 dizzy already have a melonized gear?

Has anyone any advice on removing an engine using an endless chain rather than a hoist? Might use a telehandler and endless chain to save on getting a hoist... I will probably leave the gearbox in situ if I do this. I've heard mixed reports on whether this is easier or not. I've had the T5 out before, so I'm not fazed by pulling it out from underneath first.

Do I pull the (stainless, tubular) headers out with the engine, is that simplest? Would be a good opportunity to wrap them.

Cheers all. Never-wracking times ahead...

ndndndnd

Ugh Jeez, ok.

Just noticed something about timing. The 290hp crate requires 10° initial timing and 32° total timing advance.

I'm kinda fixed with L69 timing curve that's in the ECM, which I believe is 6° initial timing and advancing to a total of 36°.

Is this actually going to work? I can't advance the 0° initial setting to achieve 10° initial advance without ending up at 40° total, which is a fair bit beyond where the 290hp is supposed to be set. And I guess if the motor is stuck at 6° initial timing it's going to make absolutely F-all vacuum at idle...

Am I screwed?

Oh dear....

midias

I think you will probably be OK. I would try running it and use 93 if you are worried about max timing.

ndndndnd

Thanks - I'm glad of the reassurance.

I'm not gonna say how much this engine is costing me over here - you'll all have kittens!

midias

The 290 is fairly low compression I think you will be OK. Use the factory distributor settings and a 350 knock sensor. You will probably need to change the rods in the carb

ndndndnd

Engine arrives tomorrow... *glances at watch* ... today!

I've been researching the timing question a little further but I can't find any conclusive answers. This thread is quite interesting:
http://www.montecarloss.com/communit...59&type=thread
On here, someone suggests timing at idle is set by the ECM at 20° BTDC, which is an advance of 14° on the 6° static (EST disconnected) which the label on my bonnet asks for.

Will that much advance at idle work? Will that compensate for the low vacuum, or will it simply kick back the starter or not idle? MY L69 obviously turns (turned...) over fine with the LT1 gear reduction starter, and I assume the 9.3 (?):1 compression ratio would give the starter more of a workout.

Does anyone know why GM ask for so little idle advance? The installation instructions seems to suggest that you set the timing with the vacuum advance disconnected.... and then leave it disconnected, with the idle advance set at only 10° with no additional advance ever offered by a distributor vacuum advance. With the ECM controlled advance I don't have that option anyway.

Here are the installation instructions if anyone is curious! https://www.chevrolet.com/content/da...e-19355658.pdf

Also interesting is the recommended break-in for the cam, which suggests you faff about at idle setting the timing and then waiting for it to warm up before doing a series of acceleration runs... which is rather directly different from absolutely everything else I've come across saying you have to immediately spin the engine up to 2000+rpm as soon as it fires to provide enough oil for the cam to bed and then hold it there for 15-30 minutes!

For contrast: Pace Performance's instructions: https://paceperformance.com/p-3978-g...procedure.html

USMC3782

How did the arrival of the new engine treat you?

ndndndnd

New engine is here, sat in a crate in one of my father-in-law's sheds. Since it's arrived, I've not even had a chance to open the crate and take a look at it!

I'm slowly gathering up components required for the swap to take place, a couple of boxes have arrived from Rockauto and I've purchased an engine hoist.

I'm currently thinking through how I'm going to do things and working out what I'll need. I'm debating whether or not to purchase an engine stand, or use the crate for the new engine and prop the old engine on a palette. I was going to pull the transmission off and leave it under the car, then pull the engine out on its own with clutch and flywheel still attached. I thought that might make it easier to swap over the flywheel and clutch between engines outside of the car, however conventional bellhousing bolt-mounted engine stands won't let me do that. I could do it using those engine-mounted storage legs, but they'll have to come from the US at some expense.

Does anyone know a good, improvised way to prop an engine out of the car?

Is it sensible to pull the engine with the bellhousing still attached? Accessing bellhousing bolts underneath seems a pain. I'm planning on using a lift plate, so I won't have the ability to level the engine as it comes out, but I will be pulling the radiator.

After my Rockauto package arrived I realised I forgot to order a knock sensor! Pondered if I could do without but it's not worth the risk. Also just realised I'll need a new pilot bushing for the new crank (I'm assuming it won't have one!) and although I ordered new flywheel bolts I was going to gamble on reusing the clutch bolts, which probably isn't worth it for the few quid they cost so I'll get those too.

I'm wondering what other gotchas I've not yet considered that are going to stop me in my tracks... Anyone got any tips a newbie might not have considered?!