Daily Driver Turbo Engine

Shaun @ Tru6 · 08-12-2014, 05:19 PM

I've had my M491 on the road for 6 months and while I love the car, it needs more power. I'm more of a lightweight guy, my 73 is 2175lb with a 3.2 w/ headers, muffler and chip. That's the perfect car for me. I can't gut the car and it's heavy to start with so I need to plug in more power. Options are a 3.6 or a Turbo engine.

I would prefer a Turbo but need the car to be livable as a daily driver. What is typically done to a 3.3 to reduce lag and make the engine more friendly on a daily basis? What are my options?

DSPTurtle · 08-12-2014, 06:28 PM

LS1 motor...

JFairman · 08-12-2014, 06:45 PM

A small ball bearing turbo that spools up early and a bunch more ignition advance below 3500 rpm.

b5aar · 08-12-2014, 06:58 PM

"LS1 motor..." Haaaa...with a kenne bell twin screw

+1 for Jim's recommendations adding aftermarket exhaust and next level would be cams before going to major mods with increased displacement, headwork etc

quattrorunner · quattrorunner's Garage

These days it's not hard to get full boost by 3k.
Turbo all the way!!!!

PcarPhil · 08-13-2014, 03:18 AM

Personally I think a N/A 964/993 3.6 is a better daily driver engine. Lots of low end torque, good gas mileage, EFI, etc.

By the time the dust settles I'd imagine the overall install cost and complexity would be about the same installing a 3.6 vs. 3.0/3.3 turbo engine.

Don't get me wrong --- I LOVE my '87 3.3 but for daily driver use I'm pretty sure I prefer the N/A 3.6.

RarlyL8 · RarlyL8's Garage

Your M491 an early version (915 tanny) which somewhat limits the power level you can go for.
Any small turbo strapped to your stock engine will get you what you want, Carrera torque down low then a nice push when boost hits. Even a K27-7200 will hit full boost by 2800rpm with headers on your engine. I'd use a GT30.

Shaun @ Tru6 · 08-13-2014, 04:22 AM

Thank you Gentlemen. If I go with a small turbo, do I have to change compression? Or is there a somewhat bolt on solution? Thanks Scott, good to know, anyone else, would you go 3.6 or add a turbo? Have a lot of time to think about it, won't start until car is off the road this winter.

I've never driven either BTW, a Turbo or a 3.6 car. Will do that before doing anything.

PcarPhil · 08-13-2014, 05:21 AM

Quote:

Originally Posted by RarlyL8

Your M491 an early version (915 tanny) which somewhat limits the power level you can go for.
Any small turbo strapped to your stock engine will get you what you want, Carrera torque down low then a nice push when boost hits. Even a K27-7200 will hit full boost by 2800rpm with headers on your engine. I'd use a GT30.

Good point. I hadn't thought about that. Especially if the 3.2 engine is in very good condition this may be a very good way to go.

Quote:

Originally Posted by Shaun 84 Targa

Thank you Gentlemen. If I go with a small turbo, do I have to change compression? Or is there a somewhat bolt on solution? Thanks Scott, good to know, anyone else, would you go 3.6 or add a turbo? Have a lot of time to think about it, won't start until car is off the road this winter.

I've never driven either BTW, a Turbo or a 3.6 car. Will do that before doing anything.

I've driven and owned both. They are very different. It's a very good idea to drive both - slightly modded turbo with 915 trans and 3.6 swapped 915 SC/Carrera. Keep in mind if you drive a 911 turbo with 930 trans the gear ratios are much different than the 915 trans. It's not an apples to apples comparison.

IMO the 915 ratios are more fun and better for daily driver use but of course the 915 is weaker than the 930 trans.

911nut · 911nut's Garage

Knowing what I know today about 930/965 Turbos, I would vote for a 3.6 in daily driver service due to the added complexity that a Turbo installation represents to any kind of maintenance.

Rich76_911s · Rich76_911s's Garage

If you didn't already have a lightweight N/A car I'd probably go the 3.6L route. Due to the fact that you have the lightweight N/A base covered I'd turbocharge the 3.2L. Variety is the spice of life, and experiencing the donkey kick to the rump when that turbo spools up is a lot of fun.

Uwon has a turbocharged 3.2L I'm sure he could walk you through a lot of the pro's and con's of the process.

Rich

Rodsrsr · Rodsrsr's Garage

Turbo-ing your 3.2 is by far the most cost effective way to reach your goal. With your 915 it will out perform the 3.6 and even a stock 3.3 at a modest .5 bar boost. Just dont drag race it.

TurboKraft · 08-13-2014, 09:27 AM

Quote:

Originally Posted by Rodsrsr

Turbo-ing your 3.2 is by far the most cost effective way to reach your goal. With your 915 it will out perform the 3.6 and even a stock 3.3 at a modest .5 bar boost. Just dont drag race it.

Listen to this guy's advice. He's got an effective simple setup on his car, clean build, very quick.

3.6 swaps always seem to cost a lot more than people budget for.

Shaun @ Tru6 · 08-16-2014, 03:18 PM

I bought myself a little time.

This FS: Sport seats out of an 86

+ this = significant improvement. Really, world of difference. I may pull the rear seats, very very carefully remove all AC, put on my old Abarth wheel and install a cat bypass. These ancient Momo's (20# each installed) were practically made for my body, might get then redone in navy alcantera this winter.

full quack · 08-16-2014, 04:05 PM

I've got my '84 930 down to 2700lbs with 1/2 a tank of gas in it. I have not butchered anything, and saved all parts for the next owner if they want a stock heavy original.

Now granted, there is no A/C, no spare tire (can not use it anyway with my wheel/suspension set-up), no jack or tool kit, no rear wiper, no interior floor undercoat, no rear seats, etc.

I still have heat, stereo and a radar detector....what else do you need!!!!!

Mark

spence88mph · 08-16-2014, 04:11 PM

I have an M491 and a similar set up to what most have said above.

It really was dead simple, I did it over a weekend at home. Has been trouble free since 2008 and makes the car feel twice as fast. You'll never go back....

RarlyL8 · RarlyL8's Garage

Another noteworthy item is authenticity. Your M491 is becoming a valuable car so you might want to leave the engine that came with it intact. You can turbocharge it with bolt-on items that are easily removed when the time comes. The 3.6L conversion is rather invasive with large coolers required in the front of the car.

Shaun @ Tru6 · 08-17-2014, 04:07 AM

Your point is well taken Brian. This is a low mileage car that sat in FL a little too long. It's a ratty car, needs paint, needs interior, but is an excellent base for restoration. Everything that comes off the car is well packed and put in storage. I like the idea of bolt on turbo charging. Is there a kit or standardized build list? I thought putting a drivable 3.3 in would be the easiest, least invasive thing to do but seems to be not the case.

quattrorunner · quattrorunner's Garage

Adding turbo to the 3.2 is cheaper by far than sourcing a 3.3. Better too.

RarlyL8 · RarlyL8's Garage

We put a 3.3T in a Carrera M491 a few years back and it was not difficult, however I would not do that now as the original engine needs to stay put. Motronic is a plus as well so win-win.
There used to be a few kits around such as Protomotive but I am unaware of any now. It is not difficult if using 930 exhaust parts and adapting an intercooler and rising rate pump to the EFI. Add a chip and enjoy!