LSx into a 951: Grassroots Motorsports forum: Grassroots Motorsports Magazine

Subscribe get a full year for only $19.95 Sample get a free issue—no strings attached

Aug. 4, 2008 10:20 p.m. dean1484 HalfDork

I have had a really bad Jones to do the LSx swap into a 951 for quite some time now. I have located a complete 951 less motor for cheep. I am seriously considering selling my 924s to fund the motor and the renegade kit. The sad part is that my 924s has had many many thousands of dollars of mods bolted on it that may actually make it more profitable to part out. I just can not bring my self to deconstruct a perfectly good running car that I have put so much time and $$$$ in to. Or I could continue to move forward with the 924ssc project.. . . .

With 951's with bad motors coming more and more available (as are crashed C5's and fire birds and Camero) I see this as the perfect "poor mans" supper car. Ya I know poor man and supper car are not words usually in the same sentence and I know that I could just go get a C5 for say 18-20K and have the same if not a better car. But dang it I really like the look of the 951. Other than the motor I believe that it is probably one of the best designed cars especially for its time. I think that for less then 20k you can have a really great car that will rival cars costing many times that amount. I also think that by doing this swap you are creating a very balanced car. By this I mean that not only will you have the grunt but you will not have to upgrade the drive line brakes or suspension as it is already very good/excellent and more than adequate to support the upgraded power-plant. This in the long run actually saves money and is in my book a huge safety factor. Many motor swaps usually have little if any thought put to upgrading the other components of the car such as brakes, suspension or the drive line. Combine this with poor budgeting or underestimation the cost of sead motor swap and it is usually very low on the list and more often then not is skipped over. By using the 951 as the platform you are eliminating this whole problem. Yes getting a 951 roller will cost more than say a 944 but it will in my book pay off huge as most of the "other" stuff is all done for you by Porsche. It also will let you just do a motor swap. You will not also be doing brakes, transmission replacement, springs, struts and on and on and on the list goes. With the 951 you simply swap the motor in. upgrade the radiator and change a master cylinder (I think) and fits with some wiring and exhaust.

The only draw back is if you want to go racing. There really would not be a place for it in SCCA. EMRA would always find a home for it (as they always do for everything) But I am getting to the age where I want to have fun. Winning only occurs for that nanosecond as you cross the line. I like to enjoy the drive and if I happen to win it is a bonus so this is why I can now justify building something like this

Ohya.. . . I ran the project by my wife and the gave it the green light. .. . I am in real trouble. Fortunately I am between garages at the moment and it is the only thing holding me back. May be the wife realises this and will change her mind as soon as the garage becomes available.. . .. . I may go ahead and get the 951 chaise and put it in cold storage as it is the exact car I am looking for (color, year options etc.)

So what am I not thinking about here? Yes I have done other motor swaps so I know what is involved both with fabrication and time and the myriad of small details that always seem to creep up. I know 944's / 951's inside and out so I know the nuances of the cars. I also have some experience with c5's and LSx motors so I also have a good grasp of what they re all about. This is not a case where I will be dealing with things that I have never put a wrench to be for. In fact nothing could be further from the truth. Honestly I can not think of a better motor / chaise combination

Lastly I dont want to here from those that say what I am thinking of doing is sacreligious. Just get over it. You will not change my mind. It is a car for Christ sake and not a rare one at that. In fact 951's are making there way to the scrap yards in droves. They are a heavy car for there size that brings good scrap value. I look at it as I am saving a 951 from deconstruction as opposed to running one. It is not a if I am taking a running 951 and ripping the motor out and doing this... .. . Actually I have thought of this as the running 951 motor would probably come close to funding the cost of a LSx motor making the only other big out of pocket expenditure the Renegade kit.

Now that i have babbled on for way to long lets here from you all. Both good and bad.. . . .
Aug. 4, 2008 10:44 p.m. MrJoshua Dork

I argue that the 3rd gen 7 is better due to using the T56 and pure sex appeal.

I argue that the second gen 7 is better from a cost perspective.

I argue that a 3 series is better due to more seating.

I argue that that the 951 sounds like a cool as hell swap and theres not a single reason (including the ones mentioned above) that you shouldnt do it!
Aug. 5, 2008 10:44 a.m. DWNSHFT New Reader

You're right, 951s are cool cars with good looks and a great performance base. I was going to warn you of the torsion bar rear suspension and that it can be make chassis set-up more difficult, but you already know about it. I'm guessing you also already know about the front A-arm failures. Yes, the cars are heavy, but I also think they are pretty sturdy.

You say you'll be able to drop in an LSx motor and be done. I think you might find that you don't have enough brakes for all that extra power. Of course, 928S4 brakes are the same as 951S brakes and bolt right on.

Good luck and post lots of pics and video when you finish it!

David
Aug. 5, 2008 11:59 a.m. racerdave600 Reader

I say do it! I owned a 951 and currently have a 944, and I have no problem with the swap. It eliminates a lot of the weak areas of the car, and retains the good stuff. A-arms and like are cheap and easy to rebuild (I just did mine, what a difference), and there are plenty of suspension pieces available. The transaxles are strong enough for 400 plus hp, and as stated above, limited 88's and all '89 951s had the big brake set ups and heavier suspension components, and are easy to swap into the the previous versions.

Good luck and keep us posted.
Aug. 5, 2008 12:10 p.m. modernbeat HalfDork

What exactly do you want to do with this LS-951? Nice driver? Track days? Time trials? Wheel-to-wheel racing?

I think the only potential use for a 951 with an LS motor and no other mods would be a nice driver. Anything else would require more.
Aug. 5, 2008 1:23 p.m. AngryCorvair HalfDork

be sure to read the mack daddy porshce hybrids board before commiting to Renegade Hybrids
Aug. 5, 2008 2:40 p.m. carguy123 HalfDork

What's a 951?
Aug. 5, 2008 2:56 p.m. modernbeat HalfDork

carguy123 wrote:

What's a 951?

A 944 Turbo.

FWIW, I've been thinking about one of these as a daily driver.
Aug. 5, 2008 8:58 p.m. dean1484 HalfDork

This is a 951.
Aug. 5, 2008 9:18 p.m. dean1484 HalfDork

I don't think you really need anything more than the upgraded brakes that the 89's had. Heck even in the stock form they are darn good brakes my 924s with just a pad upgrade has never had a single issue with brakes on the track. With the 951 they are upgraded from the base 944 and again they were upgraded in 89.

This has always bothered me. Brakes don't stop HP they transform the energy of motion to heat. Energy is the mass/weight of the car times the velocity/speed. Nowhere do you have HP in this equation. Therefor since this swap only adds about 70lbs to the car (about the weight of a Kid in the back seat) I don't see a brake upgrade as being a must do for this swap. I do concede that the 89+ cars and the M030 cars are better and if the track/computishion is in the cars future this is a should have option but for the street I can not see that the brake upgrade is a must have option as we are not changing the mass/weight of the car enough to warrant it.

But yes for my wants/needs it will be a 89+ spec car.
Aug. 5, 2008 11:04 p.m. Josh Reader

Regarding upgrading the brakes "to match the power", maybe the car doesn't get much heavier with the swap. But it does get faster. Which means on a given track/road, you have the capability to go faster entering each corner. Which means you have more kinetic energy that needs to be converted to heat. Which means the brakes that never had to work this hard when the car had less power may no longer be up to the task. Basically, when you make a car accelerate faster, you are giving it an ability to accumulate kinetic energy at a greater rate than it could before. Which means you should probably also consider increasing the rate at which it can dissipate said energy, even though the weight isn't much different.
Aug. 6, 2008 9:05 a.m. dean1484 HalfDork

Josh. I here you! The speed at witch you accumulate energy and the amount you accumulate are two totally separate things. How fast you generate energy has no effect on the abilities needed dissipate it. Now if you decrees the time you have to dissipate the energy that is different or if you increase the amount of energy to be dissipated in the same time period that is different.

I don't disagree with what you are saying. I have a problem with doing something to a car because "the car can do something". The car can not do a dam thing by its self. Everything it does is controlled by the driver. If the driver is stupid and over drives the car they will crash. Give them better brakes and they can over drive the car more and crash worse. Just because a car can get to 120 at the turn in to a corner does not been you should do 120 at the turn in. The driver is responsible for determining this. The driver is responsible for determining there braking point. If they can not figure this out adding bigger brakes is not going to fix the real problem with the car that is sitting in the drivers seat.

I have seen this happen in revers on the track with novice drivers. They will hit two or three turns in a row perfectly and get a great run going down a long strait. Because there exit speed on to the strait was say 15-20 mph faster this equates to a much higher terminal velocity at there usual braking point and they are in trouble.

I guess I don't like being told I have to upgrade something because other people may be stupid. It just bothers me. I understand it bit it still bothers me... . . And getting sued sucks.

Getting back to the 951. Yes there are brake upgrade options and yes I am looking at the 89+ spec car but I also feel that the pre 89 951 brakes would be plenty for the car for the street or even an autocross or three. HPDE days or road course racing upgrading would be a necessity.
Aug. 6, 2008 9:50 a.m. racerdave600 Reader

I've owned an '86 951 and driven an '89, there is a difference in the braking and you can feel it. Not that the others are bad by any means, they're awesome, but you can definitely tell, especially from high speed repeated stops; ie track days. The biggest difference between the two are the older 951s have the 4 piston calipers, the later ones have 6, plus bigger rotors and ABS.

Compared to my NA '89, both are vastly surperior, and these are pretty good too. There's also more to the '89 than just brakes, the suspension is slightly revised, and some of the components are beefier.

The '89 is a better car all the way around as they've worked out some of the quirks, but personally, I'd take any year. I'm always on the lookout for another one, but it'll have to be the right car this time. I'm much more concerned about condition than year.