davek9

Hi Doc, I worked on Robert Budd's converted '78? Auto, and it did run good once all was sorted out, he also needed different springs in the front due to less weight, so consider that need as well.

Given the effort and $'s involved to do the conversion, the only plus I see is in having a less expensive engine to support with less expensive HP options, this do to the quantity of chevy V8's out there. It will be a "special" car once its done, and fewer shops will want to work on it. If you do it make sure you document all wiring as it will be a "mixed" bag, this was the hardest part on Budd's car, the lump was easy.

Just to catch up on your current situation; have you ever pulled your 20 something 5.0 ltr 32 valve 4 cam hemi all aluminum Porsche engine and gone through it? (not a total rebuild but a decent refresh).

IMHO to many pick at these cars, piece meal and are haunted buy gremlins.

Thanks,
Dave

Iwanna928

It is your car so I wish you the best!

Sometimes a new set of eye's and hands can make all the difference. I can only speak for myself but I get so wrapped up in my cars that sometimes I can not see things clearly or hear things that are suggested.

I am not saying you are doing this, I just know I have and then I regret certain decisions I have made.

My 79 took more abuse than any car I have ever owned. I have owned many 5.0's and 350's and none of them would have survived.


A LS with a 6 spd sounds awesome!!!!!!!!!!!!!!! just not in a GT. Either way I will be watching your build!

Maleficio

That dude that installed twin turbos on his 928 and now sells the kit, didn't it have over 400k miles on the engine, and had never been rebuilt?

BC

No - Greg said it was the most reliable Porsche engine.

I have thought about a small block in a 928. Its sort of a fun idea. But the potential has not been wrung out of a 928 motor yet.

And doing things right can make a big difference. The first time. Not being afraid to pull an engine and put the right, new, parts on ( I have personally failed at that a few times, learning all the way)....

If you are talking about an old efi small block, thats a load of crap. The only swap should be a nearly new LS based, if anything.

anonymousagain

Hello Doc, I'm familiar with the LS swap with Renegade conversion pieces through a friend.
His motivation was,
* a blown porsche engine
* he had an LS engine available
* he fabricates as a hobby
* he thought it would be less $$
* he thought it would be fun

90%+ completed and much learned, but fundamentally, it looks easier than it is from the "outside" (as Greg appropriately described). Also, cost was nearly 3x initial estimate... although, not sure what a replacement 5.0L S4 would have cost to compare.

The "conversion kit" is a loose term, probably more accurate as a "start the conversion" kit or a "some really good key conversion pieces" kit, but definitely not a conversion kit that will allow you to complete the project without your own fabrication.

If you appreciate the fun-factor of the swap process, you're a creative problem solver and meticulous to figure out the ambiguity correctly, there are many benefits with the result and you should go for it.

If pulling an engine, re-wiring harnesses, or fabricating fitment is not your thing, an LS swap is likely the wrong PITA to take on.

FWIW, get the GT engine up to maintenance/stock standards first, then decide if you still want to pursue the LS swap. If you decide to do the swap, at least you'll be storing a ready-to-run engine under the bench, rather than a might-run-okay engine to have to deal with down the road.

Will see if I can dig up some pics to post - looks very, very clean. And yes, he would do it again under the same circumstances, simply because he enjoys this kind of journey.

GregBBRD

Very well said!

Hilton

Go buy the motodyne kit

Then afterwards, cut your losses and put the GT engine back together

More seriously - I figure the path of least resistance/expense is buying a used 90+ S4 engine, replace all the rubber stuff on a stand where its easy, stick the GT cams into it, and be done. Given you're talking DD rather than track duty, you don't need any cunning oiling mods.

TexasDude74

I'm all for an engine swap that's cool and modern. An old T-fitty cheby is neither. Any swap is going to require custom parts, solutions and labor that will exceed the cost of rebuilding the current engine or finding a good replacement. Once you admit that a swap is not going to be a money saving endeavor, you can go down a different path and have some fun, with a unique power plant in your 928. Ferrari built, flat crank Maseratti engines can be found complete for $4-6k. That would be cool. The big AMG 6.3 V8 is widely considered one of the best engines ever, complete pull outs can be had for under $10k. That would be cool, and still German.

docmirror

Meh, now reading this it's motivating me to go fiddle with the engine some. Sadly, I've just had a setback on my 968. Another never-ends project. Prolly my fault though, I put a new Bosch fuel pump in June 2012, and it just crapped out. Bad mechanic and all that I am. I also just had to fix my air compressor, so at least now I have air tools back.

SeanR

Doc, I know you hate to part with cars, but you can let me work on them and get them running. Ya might not be able to keep the Ferrari running next month but at least the P-car will be reliable.

docmirror

Ferrari is running quite well, except the CIS injectors are just too gunky to run smooth off idle. With a nice infusion of money I just solved that problem today. Roger is getting me 8 new ones on Friday. I guess I'll have to change the rag top now.

I'll think it over. The head job isn't that messy, but it's enough to be an irritation.

Mrmerlin

Doc you never did explain the reason for the GT engine failure, would you care to provide more info?

docmirror

Seized 2/6 rod bearing on the track. But before that was plenty of grief, and some self-inflicted issues as well. Can't blame the engine for my stuff, but I'm not really interested in continuous working on the lump.

When I get the 968 pump and shocks in, I'll go back and start on the 928. In late Nov my new plane arrives and I'll be spending a lot of quality time fiddling with that new toy. Motivation to finish the 928 I guess. Maybe after I get it all apart, and sort out the issues, I'll have Sean come down and we'll blitz through the assembly and stuff.

ThetaTau87

This is good to hear. I have zero experience with a SBC swap in a 928 and very little 928 experience in general, but I have done a "bolt-in" engine swap with a "kit" that came with "all the parts needed to complete the conversion" on my old Corrado. LOL, pure folly!

Budget? Toss it. Or at least double it as a start. Eventually you'll just stop keeping track.

Time line? You'll learn not to set deadlines anymore.

The words "kit" and "bolt-in" will forever be sore spots in your vocabulary.

The "kit" came with all the major parts to bolt a 16v VW engine in place of the 8V G60 engine that came stock. It even used the same fuel injection system so no swapping computers and rewiring for a new ECU, etc. Never were the words "The Devil's in the details" more true. I spent weeks and weeks sorting out all the plumbing, wiring and other ancillary bits that needed to be modified, relocated or just plain fabricated from scratch. Bolting the engine in was the easy part. Making it run took months and getting it to run well took years. Eventually it got to the point that I was tired of trying to chase down one thing after another that was not quite right even a decade AFTER I got it running despite my meticulous attention to detail with the initial build. I wasn't driving it much at all, so I sold it and bought a car I could DD, a 928 GT.

This was with a swap that received Oooos and Ahhhs any time I lifted the hood. I was hero status on the Corrado forums for one of the cleanest 16v conversions anyone had ever seen, but they didn't have to live with it. The cool factor was off the chart, but I don't think any swap can rival a well maintained car that is mostly stock for reliability. After that project I resigned my car projects to true bolt-on parts that don't modify the car from how it was designed by the factory. I couldn't be happier with my stock 928 GT and my bolt-on modified Audi UrS6.

If you think trying to diagnose and fix a stock 928 is difficult, try it with a one-off bastard of your own creation. That's when kicking yourself in your own *** takes on a whole new meaning. A SBC may seem like a cheap easy way to get a reliable DD 928, but I suspect it's a false economy. There's a reason you don't find many fully documented swaps in write ups online. It's because the process was too painful and or too messy to document and leave evidence/memory of how much blood, sweat and tears it truly takes to do it.

SeanR

Give me the injectors, you've seen that nifty cleaning jig I've got.