Most cost effective way to Increase performance in 76' 2.7 engine???
 

Hello Group

Thanx

SSI headers/heat changers made a noticeable difference on my 1977 2.7.

Cost efficiency
 

This is increased performance
80 3.0, 9.3/1 CR, easy 200 horses with more available. A couple more hours work needs to be done to finish
http://forums.pelicanparts.com/uploa...1439147807.jpg

86 3.2 9.5 CR easy 230 HP with chip. Several more hours work to fine finish
http://forums.pelicanparts.com/uploa...1439148007.jpg

Backdated SSI exhaust,
CIS S camshafts if you have the standard camshafts.
Left 911 105 143 00
Right 911 105 144 00
Plus the usual tune up, distributor check, CIS air leak, and fuel pressure checks.

I'm interested too, I have a set of SC grind 3-bearing cams that I heard make a difference w/o messing with Ps & Cs.
My car is a 914 conversion that I'll run headers on (/6 HEs are too $$ for me to afford), but in a 911 the SSI backdated HEs should help produce the same results with heat.

I'll probably end up having my engine guy take a look and give his 2-cents if it's a cam-swap or a full redo needed.
If I do a full rebuild, I'll post up my cams for sale...but I have no ETA on when he'll get it in for a look.

It's been mentioned here before so I'll throw it out there. The easiest and most effective way to get more out of your engine is to lose weight.

Thanx Esully

Left 911 105 143 00
Right 911 105 144 00

this means???

newbie here sorry

5' 11" 190

weights in check! LOL

RoguePorsche:

Esully provided you with the Porsche part numbers for the left/right S cams.

I have a '75 with a almost-freshly rebuilt 2.7 in S trim, SSI's, well-tuned ignition and CIS, and some weight stripped out of the car. It revs great and I'm not wanting for power. (Maybe I don't know what I'm missing, but this config is more than enough engine to get into lots of trouble.)

Your car may already be the S spec engine. I think they only offered that version in 1976.
Interesting that the 1974 S was rated at 175 hp, and the 1976 was 165 hp. I'm not sure what was done to detune the engine.
There is an ID number on the engine, 911/xx, by the right side of the fan. Can you post yours?

Thermal reactors and smog pump.

Funny! I believe when he said to loose weight, he meant the car.

Well, that too... :D

While there are only so many horses on the table upgrading internals and it gets $pendy very quickly, there are plenty of threads here of users putting their cars on a diet, some losing quite a bit for free. I think the sound deadening in the tub and engine bay alone is close to 30 pounds. It gets harder as you start looking at lighter components like carbon fiber panels. Then there's the folks who like to drill out parts. I'm just pointing out, there certainly are some economical ways to increase your power/weight ratio by putting your car on a diet.

Hello,

….would to hear your list on lowering cars weight

thanx
R

Subscribed

Lowered weight of my 74 by replacing front and rear bumpers with fiberglass RSR version, removed rear seats, replaced front seats with racing buckets, replaced interior with RSR version, removed entire a/c system, removed footwell blowers, removed main blower in frunk, removed rear wiper, converted power windows to manual, removed rocker covers, replaced steel wheels with aluminum, removed 2.7 engine. I then added a rollbar and a 3.6 from a 95 993, so I put some back.

if doing a rebuild/refresh on a 2.7, is it difficult to bump up the displacement to 2.8/2.9/3.0 litres? is it a case of chucking in new pistons/barrels?

Hello Gang,

70' 911t/ 76 2.7l engine

did a compression test ;(

left
42 psi, 115psi, 90psi,
right
117 psi, 117 psi, 115 psi

…going to put oil in to the"42psi" cylinder to see if its pistons or valves.

PS: Car sitting for a long time, changed oil & spark plugs (spark plugs BLACK) hence us

doing a compression test.

ANY ADVICE on what to do next???

Thanx
R

If the engine has not been running lately, it is hard to tell from a compression test what is wrong. Rings could be sticking, carbon could prevent the valves from sealing. I would say the minimum should be 125 psi. A leak down test could give you a better idea of where the problem is.
With a leak down test, if you hear air coming from the intake or exhaust, then you know the valves are not sealing.
If you hear air in the case, the rings are not sealing.
Black plugs could be oil leaking past the valve guides or rings, or rich mixture. Worn valve guides won't show from a compression or leak down test.
Mid year cars also had a problem with head studs pulling from running hot for emissions during that time period. Have you checked the torque on the head stud nuts?

SSI's add a decent amount of thrust. I have these going into a 2 to 2 Dansk muffler on my SC. A little too loud for me but this helps the more efficient headers breath. Plus, you get rid of the heavy CAT and the header crossover which just adds heat and more back pressure. My 2.7 has SSI to a 2 in 1 out muffler arrangement which sounds better (quieter) but probably less performance.

One of my hot shoe mechanics - John Butz from CB, was mad at me for not installing the alum pressure plate on the clutch. $871 from our host but you lose about 5-6 pounds exactly where you need to and the eng will spin up faster. I was too cheap.

There are alot ways to trim weight off the engine. You can hack off the bosses on the intake runners that aren't used. You can use alum and ti fasteners all over the place, alum fan strap, hole the aft eng mount, make a lighter bellcrank plate, use alum rod for the throttle pushrods, a lighter cooling shroud etc etc.

Unless you want to spend alot of money, the exhaust will give you the most bang. But you must do the Raceware studs and the case counter bore and Time Certs otherwise they will pull out.