1987 944 Turbo --> LS

HI Chrenan. Can you tell me where you got your hood? I need one like that as well.

Hotrodz of Dallas wrote:HI Chrenan. Can you tell me where you got your hood? I need one like that as well.

Hi Bob, hood is here:

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Vents came from here:

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Awesome. Thank you sir

acorad wrote:beautiful

Yep. Very cool!

I just read your entire build in one sitting.

Thanks for putting the effort into documenting so much - I appreciate this a lot.

I'm also in the Great White north (Seems a few of us here are) and I also am at a crossroads with my car. I have an 944S which is a fantastic car but the engine is starting to give me that "I need a rebuild" feeling. If it was totally healthy I would leave it stock (power wise) as I'm a huge fan of 'slow car fast' and keeping my foot buried for long stretches. It's fun to live at high rpm.

... however, these engines are old and mine is starting to consume oil and give some other signs of needing a rebuild. I'm starting to have a really serious conversation in my head about what to do next if it pops. The S is cool, and unique... but... well I don't have to explain the appeal of the swap to this crowd.

My thinking was to remove the factory engine for now, and (reversibly) do the same conversion. I can then take my time and build a great little n/a S engine over time.. or just keep it for collector' sake in case I ever sell.

The weights that you posted - thats amazing proof against the nay sayers

I've always though the 'you'll ruin your car!' crowd were being a bit ridiculous, so it's nice to see some data to back that up. I noticed in your videos you're short shifting. Such an alien concept coming from a powerplant that only makes its power from 4500-7000 rpm  

This thread has moved the needled in my internal discussion towards "okay, this ticks all the boxes"

You've sort of done this twice now. Would you stick with the LS2 if you were to do it again?

Any major hardparts you would avoid next time... or ones you would buy that you didn't?

I have been a member of this forum for a few years now and everyone has been tremendously helpful with any questions I have had. I put a LM4 5.3 aluminum LS in a 1988 944 and I am very happy with the results. I had it running this spring and have put about 2000 miles on it so far. There are loose ends to tie up but they will probably wait until this winter.
In my opinion, here are some of the things you should think about:
An aluminum LS is preferred over an iron one.
Truck engines are a lot cheaper but the front belt drive is an additional cost to make it fit.
The handling is not affected by the engine if you use an aluminum one.
Hydro boost is the way to go.
The sub frame spacers are nothing to be afraid of.
Brake upgrade is a good idea for your S. I put Turbo S brakes on my car.
Kent at TPC is very helpful with advice regarding parts.
The driving characteristics of the car change completely because the engine has torque. Very cool.
You can convert a car to an LS and change it back to the 4 cylinder without any damage.
Don't think you are going to convert your car for less than the cost of rebuilding or modifying your Porsche engine. It will cost more than you think.
Use this forum to its fullest extent. There is a ton of information here.
Is it worth the cost and time to do the conversion? Absolutely!!
I hope you decide to take the plunge. Good luck, Gil

Gil nailed a lot of it. I’d do it again in a heartbeat, I didn’t even cut a wire on mine, the stock engine is in the corner of my garage and a future owner can put it back in if they like, no cutting, welding or drilling on the car happened. If I had to do it over I would have started with a crate engine first time around instead of a used one, which was a dud, then having to pull it and put in a fresh engine. Of course I didn’t know how well it would turn out when I started, so it’s “hindsight is 20/20” on that one. I have learned that there are “levels” of domestic parts. When I first did the swap I was lured in by how cheap everything was. Some examples are the alternator, bought the cheapest one I found new, it failed, replaced with a new more costly ACDelco professional line version and it’s been fine. Similar story with C5 fuel filter regulators, the cheap ones fail, the more expensive NAPA Gold/WIX version do not. Other advice? Press the easy button and buy as much as you can from Kent. There’s plenty to sort out yourself even when you buy a full kit, so make life easy on yourself. If I’m doing lazy laps I shift somewhere between 5000 and 5500. If I need to pass or get away from someone I’ll run it up to 6000 or a little over, rev limiter is at 6500. It’s a ton of torque down low in a light car, it feels very understressed and picks up speed deceptively quickly because it never feels like it’s working for it.

You guys nailed it. Those are the best comments on building one of these cars that i've seen.

Thanks fellas, Helpful replies from all.

Gil: Funny your comment on cost of rebuilding my m44.40 vs an ls swap. I've tinkered enough that I actually assumed it would be cheaper to rebuild my m44.40. In part because I've done swaps before (BMW V8 into an e34 5 series wagon) so I know how costs can add up and that was a 'plug and play' swap... but also In part because there is no damage to my m44.40 yet. The short block is the same in all 944 models more or less so although my S head is a $$$ core with $$$ parts in it due to how uncommon they are... the bottom end is common and easy. I do also do everything I can myself, so that helps.

I only really had two concerns with this swap, one was I do feel the character of the car will be altered and I struggled there a bit. I really like wringing out this engine and driving this car and its fantastic controls. I've concluded I can live with that - it's just a chapter in the car's life and reversible.

The other bigger concern was handling - not just about speed either, but feel. I worried an even slightly heavier front end would change something enough that it would leave me liking it less. I'm not a track rat like some of you here - I do dabble but my favourite way to spend a weekend is Navigational rally, exploring the remote roads of BC where I live. The hard data on the total lack of weight gain really, really helped. I'm starting with a lighter car, turbo vs S is about 60-100 lbs, so the balance may be ever so slightly different when I'm done. I have already dropped a fair bit of weight in my car as it's a little gutted, so if the balance is noticable in feel I can put some parts back on the rear

I will absolutely reach out to TPC based on the glowing advice here, and I will not muck around with thinking I can reinvent the wheel on those hardparts.

The Hydroboost setup is interesting. Never driven a car with it before. Is there any notable difference in pedal feel?

I could talk all day about this so I'll wrap it up - the more I think about this the more I'm confident it's the right choice for my car. An under stressed engine making something around 300 whp with potentially identical weight and near as makes no difference the same weight balance as before - and actually pretty importantly - the ability to find replacement parts in any podunk town with a Lordco or Napa. Let me tell you how many times I thought "what if some Porsche only part breaks this weekend, 1000km from the nearest Dealer"

When I start my build, I will start a thread. I'm obsessed with weight, and I have access to a large, calibrated industrial scale that I can  use to weight the two engine sets as I do this. I'll also try to get corner weights before/after as well.

I am totally derailing your thread here Chrenan, sorry for that. You can have it back now I just wanted you to know you helped me decide on direction.

Here's a couple pics of my 944S with its Widebody front fenders to make up for the thread jack:

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As far as cost of rebuilding a 944 engine, it varies with level of work needed and whether the owner can do the work himself. I just did a complete rebuild on a 944 turbo for a client. Due to the extensive wear it required a lot of new parts. Plus rebuilding the head which is only 8 valves compared to your 16 valves. His bill was about $10k parts and labor.

As far as the character of the car goes, yes it will change. Almost everyone that has driven an LS swapped 944 has commented about how Porsche should have built it this way to begin with. It's like the 944 was meant to have way more power. Track feel and even spirited road driving feel, honestly doesn't change much, other than having the ability to step out the rear of the car anytime you want. There is so little weight difference, that the car drives the same.

Hydroboost does take a little getting used to. It takes less brake pedal pressure to get the car to stop. But, it's not so bad that you can't get used to them pretty quickly. With your S brakes, the car will stop really well.

I built an 87 NA 944 with an LS1. It has full interior, ac, heat, and a lot of stereo system. It also has a 968 trans which is slightly heavier. The car weighs 3100lbs with a half tank of gas. A stripped 944 with an LS can easily get down to 2500lbs.

Out of curiosity, what wheels are on your car?

My 951 was lighter after the swap. If you’re able to notice the difference in weight with an NA car you’re a much better driver than I am. As Hotrodz said above, the hydroboost requires less pedal effort than the stock vacuum booster. That took me one track day to get used to. It took me longer to get comfortable with the off throttle behaviour on track of a high compression NA engine, there is a lot more compression braking than I was used to with a stock 951 engine. No worries on fears of derailing the thread, this is what’s its all about!

Here’s a 944 NA (445lbs) engine weight compared to an aluminum LS (487lbs).

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The S engine is about 30lbs heavier than the standard na engine, due to the 16 valve head and massive intake manifold.

Hotrodz of Dallas wrote:
As far as cost of rebuilding a 944 engine, it varies with level of work needed and whether the owner can do the work himself. I just did a complete rebuild on a 944 turbo for a client. Due to the extensive wear it required a lot of new parts. Plus rebuilding the head which is only 8 valves compared to your 16 valves. His bill was about $10k parts and labor.

As far as the character of the car goes, yes it will change. Almost everyone that has driven an LS swapped 944 has commented about how Porsche should have built it this way to begin with. It's like the 944 was meant to have way more power. Track feel and even spirited road driving feel, honestly doesn't change much, other than having the ability to step out the rear of the car anytime you want. There is so little weight difference, that the car drives the same.

Hydroboost does take a little getting used to. It takes less brake pedal pressure to get the car to stop. But, it's not so bad that you can't get used to them pretty quickly. With your S brakes, the car will stop really well.

I built an 87 NA 944 with an LS1. It has full interior, ac, heat, and a lot of stereo system. It also has a 968 trans which is slightly heavier. The car weighs 3100lbs with a half tank of gas. A stripped 944 with an LS can easily get down to 2500lbs.

Out of curiosity, what wheels are on your car?

The wheels are "DTM Fiberwerkz" [You must be registered and logged in to see this link.]

They're a BMW oriented brand but these folks stock a blank and have an option for 5x130 drilling on their site. They're a good wheel. I think they're rebranded, made by ESM. Not priced too high so I don't mind taking them on a lot of gravel or winter roads and getitng them scratched up. They were the exact size I needed and I love the look - period correct too as it's inspired by 80's DTM cars.

The weight was surprisingly not too bad. Going from my factory staggered setup 16" teledials to these 17x8.5 et35's with a 245 square setup I only gained 4 lbs per corner ( 6 in the front, only 2 in the back!). I am pretty hard on wheels with the roads I explore, having cracked a couple factory forged wheels in my time... so I will see how these do long term. They seem beefy enough.

As for brakes, I'm fully prepared to upgrade if needed - I will say I have been extremely impressed with the 'plain' S brakes. With good fluid and a street/track pad they rival bigger brembo setups I've had on other cars. End of the day even 'base' Porsche parts have a lot of capability. I wonder if a big part of that is my car being pretty light, as well. If I do find that the extra speed puts too much heat into them, I will likely try the wilwood upgrades for these as I'm interested in clawing back some of that unsprung weight I gained with the wheel/tire upgrade.

I can totally understand what people say when they say 'it should have come this way'. These cars are really happy at speeds that the stock engines struggle to hit, and have way more chassis than you need with the stock outputs.

chrenan wrote:My 951 was lighter after the swap. If you’re able to notice the difference in weight with an NA car you’re a much better driver than I am. As Hotrodz said above, the hydroboost requires less pedal effort than the stock vacuum booster. That took me one track day to get used to. It took me longer to get comfortable with the off throttle behaviour on track of a high compression NA engine, there is a lot more compression braking than I was used to with a stock 951 engine. No worries on fears of derailing the thread, this is what’s its all about!  

Here’s a 944 NA (445lbs) engine weight compared to an aluminum LS (487lbs).

Cool, you already weighed it. I can't ID an LS by sight, is that the ls2 and is that full accessories bolted to it?

I bet my stock engine/accessories will be quite a bit heavier than the 8v, but probably a bit lighter than the turbo if you weighed it with headers/crossover/etc. The end result should be that my engine and the ls that will replace it weight basically the exact same.

And by the way you're right that with minor differences of 30,40 lbs balance I won't notice- i'm not that good of a driver. I made that comment about adding weight back pretty tongue-in-cheek.

Thanks for the info about hydroboost feel. My S is already high compression so it has decent compression braking, but I expect the ls would be more, just due to having more cylinders, more friction from more parts, etc...

Those wheels are awesome. We built a Baja 944 turbo. Went with method off road wheels. But, I would have used your style if I had know about them

Reason wrote:Cool, you already weighed it. I can't ID an LS by sight, is that the ls2 and is that full accessories bolted to it?

Not my pictures, but that was a 5.7 LS1 with full accessories and exhaust manifolds (the 944 has those attached as well). Any aluminum LS, whether 5.3, 5.7, 6.0 or 6.2 will be very similar weight.

Chrenan I liked your solution to moving the coils into the header panel, but looking at your pics now they're back in the stock ls2 location. What happened there?

Good catch! I liked that location too! I changed back to the stock location for no good reason actually. When I was first getting the car running I had trouble with a hard starting condition. Turns out I had wired the ignition incorrectly and it wasn’t getting a clean 12V signal while cranking. However, in my quest to find the solution (wiring is not my strong suit) I was grasping at straws and thought maybe the long ignition wires were causing issues, so I switched to the stock location. I could put them back under the nose panel now that I have it figured out, but I’ve been too busy enjoying the car.

Got it. Makes sense. I was thinking to use the header panel as the intake source, but the coils would certainly like living there too, so I was curious.

I noticed the small details as I've been pouring over builds for a couple days now.

I like where you put the hydroboost cooler by the way - my car uses that exact same spot to mount a factory ignition final stage, which mounts to a big aluminum heatsink so the space is clearly designed to be subject to airflow even without lifting the light up.

I think some S2 also used that spot but I think eventually they integrated it into the DME directly.

Hey while I'm asking questions here... any Canucks have a recommendation for a good crate engine source with reasonable shipping to the west coast of Canada? I'm on Vancouver Island. Doesn't have to be a Canadian source, but obviously it's preferred due to the current border situation and mail slowdowns.

I’m in Alberta, Turn Key Engine Supply in California got the long block LS2 engine to me for $5500 US plus a couple hundred for shipping. That’s when the exchange rate was more favourable. Locally the prices weren’t as good from builders, and not knowing the local LS community well I couldn’t tell who was good or not.

Just a regular check in, still out there doing it on track, having fun and breaking hearts.

Follow me on instagram @944TrackRat

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My swap has been up and running 5 years.  I'm switching my engine management over the winter to a different ECU and harness. With the new setup the ECU controls the alternator.  Previously I had the blue wire on the 2-pin 944 alternator/starter plug wired into the L terminal on the alternator plug. Where do I send this blue wire now if it's not needed to excite the alternator?  How do I make my volt guage and volt light work correctly?  

Thanks for any help.

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Halfway through another great track season, still loving the LS swap!

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somehow i completely missed this thread and then realized i found a fellow Albertan with a 948 tracking his crazy build. Great car, great story and awesome info on weights to which Bob has an awesome detail with my car being a 944S so my LS1 swap is basically same weight from all the info on the previous page of posts.

Also a salute to @reason with his crazy wide front fenders. that looks pretty aggressive and awesome. Also you narrowed it down to where your from with being parked at Mt. Begbie brewery lol. Awesome beers as well.

Cheers!

Gutterboy wrote:somehow i completely missed this thread and then realized i found a fellow Albertan with a 948 tracking his crazy build. Great car, great story and awesome info on weights to which Bob has an awesome detail with my car being a 944S so my LS1 swap is basically same weight from all the info on the previous page of posts.

Also a salute to @reason with his crazy wide front fenders. that looks pretty aggressive and awesome. Also you narrowed it down to where your from with being parked at Mt. Begbie brewery lol. Awesome beers as well.

Cheers!

I didn't know there was another builder so close by in Calgary! Do you have a build thread going I couldn't find it?