More HP from 3.2

[cmcfaul]

Hello,

Prob a tired topic but I will rebuild my 89, 3.2 engine this winter. It needs more HP. Assuming the jugs are in spec, what's the best Piston / CAM combo.

Single plug
Motronics ignition with SW chip.
cat delete with two out muffler
stock HE's
140k mi
Runs perfectly (some chain noise)
premium pump gas
will upgrade rod bolts

Are JE pistons better than Stock?

Thanks,

Chris

[PeteKz]

What do you plan to use it for? Street, track, both?
What's your budget? Yeah, you will probably exceed it, but have some number in mind before you start down the slippery slope.

If you do this yourself, and you want to keep costs in a reasonable range, do NOT split the case. At 140Kmi, and your oil pressure is normal, the bottom end is fine. Unless it's leaking and you really want to reseal everything, leave it alone. Henry will piss on me again for saying that, but if you are a DIYer, and there isn't some evidence of lower end problems, there's no reason to do so on a 3.2 case. They are very durable.

If you are building a race engine and you want to cross drill the crank for high-RPM use, then yeah, split the case and add several thousand dollars to your budget. Otherwise, if it ain't broke, don't fix it.

Henry and others can suggest specific cam and piston combos better than I can. However, you might consider the "faapgar" pistons. See the threads about that.

[Mr. Merk]

Here is advice I've gathered from those that know more than I do

10.5:1 3.4L or 3.5L Mahle Motorsport P&Cs
Ported heads and 40mm thin stem valves from Xtreme cylinder heads
964 or 20/21 or 993SS with 12* LSA Cams
Factory valve springs with Ti retainers
Bored throttle body
MAF conversion (Sal Carceller)
ARP rod bolts
993 Turbo studs
Porsche Motorsport bearings
Crossdrilling the crank center main journal
grooving the center main bearings
modifying the center main oiling passage way to match
M&K headers part# MK-HE163L-911
KEP pressure plate
AASCO flywheel

Keep your wheels light and don't get too big of a tire

Originally Posted by PeteKz

do NOT split the case. At 140Kmi, and your oil pressure is normal, the bottom end is fine. Unless it's leaking and you really want to reseal everything, leave it alone. if there isn't some evidence of lower end problems, there's no reason to do so on a 3.2 case. They are very durable.

100% agree. My oil pressure, leakdown and compression numbers were great. So we are just doing some upgrades and repairs to the top end while its apart for the clutch

Items shown in BOLD above

[mepstein]

I’m not sure I would tear down a “runs perfectly” engine just to change rod bolts and pistons. If you are keeping it single plug and motronic, the changes that you are asking about won’t make much of a difference. Sure, it’s your engine to do what you want but it will cost money and a good bit of time just to get a bit of a bump. I really like 3.2’s and you can definitely get a lot more out of one but it’s a combination of a lot of things that get you a noticeable power increase.

[cmcfaul]

I know Porsche did not leave a lot on the table. but if i am taking it apart to do the normal stuff, valves, guides, seals, chains, ramps, rod bolts. Is there an easy way to get 20+ more HP.

On my 73 E MFI 2.4 I increased the CR and ground the CAM to a DC30 profile and man that was a good recipe. It ran like a 2 stroke past 7k RPM's.

Is there not a similar combination for the 3.2? I dont want to split the case (oil pressure is fine and no leaks). I would upgrade pistons, cams and bolts. Would prefer not to replace jugs if still in spec as then it gets expensive.

Seeing if there is a good option here (while its apart).

Thanks,

Chris

[PeteKz]

Well, you can get 20 HP with just the chip and 93 octane gas. Add the large diameter SSI's and a low restriction muffler to pick up a few more. More than that will require different shape and higher compression pistons, and cams.

Bottom end: Nothing you do there will add power, unless you increase the stroke by installing a longer stroke crank and rods. $$$$

Mr. Merk also said something that reminds me: Replace the lower head studs if they are Dilavar. Use the Porsche steel studs. You can use prettier and stronger aftermarket studs, but they do nothing to add HP. If you aren't racing, then the Porsche OE studs are more than adequate for the job.

It sounds like you are cost-conscious, so before you pull the engine, write down your objectives, then what it will take to get there, then what all that will cost. If you don't have broken head studs or some other reason to drop the engine, just put on the SSI and muffler and install the chip. Then drive it for awhile and see if you want more.

[mikedsilva]

Turbo.

If everything else is "fine", add a low boost turbo setup and have an easy 300-350hp and gobs of torque.

Don't 'waste' money on anything else.

[Henry Schmidt]

The weakest components in the 3.2/3.3 are the rod bolts.
Failure rate for these undersized bolts is astronomical. Evidence for this statement is the rarity and price of a used, std/std 74.4 mm Porsche crank.
The 74.4mm crank uses 9mm bolts vs the 10mm bolts used in almost every other 911 Porsche engine. These smaller bolts were use to create oil pump clearance with the larger rod journal. Strangely enough, the larger rod journals were never used in factory race engine. Even the GT3 engines use a journal configuration similar to the 911SC.
If your plan is to create a performance 3.2, always start with a sound bottom end.
If budget requires the use of stock rods, at the very least, used ARP or Raceware bolts.
As for bolt on performance, bigger is better. Stay away from compression enhancements. Compression is always a challenge to street gas. No need for porting.
If you have a tuner who can create the appropriate chip, I am a have fan of DFC DC 43x 109 LC.
Clean headers/exhaust will probably offer the greatest seat of the pants enhancement. If nothing else, the cool sound might convince you that your engine is singing.

[cmcfaul]

I have the SW Chip, cat delete, 2 out muffler KN airfilter Shes giving all shes got but its not enough.

$8k for side turbo is an option but would rsther do it internally. Soumds like.the only option is to to increase displacment. New p's and C's gets expensive.

Guess new rings, bolts and topend rebuild.

A bit dissapointing. Turbo.kit seems the biggest bang for.the buck. Have to convince myself to spend the money or not.

Chris
89 carrera

[Henry Schmidt]

Originally Posted by cmcfaul

I have the SW Chip, cat delete, 2 out muffler KN airfilter Shes giving all shes got but its not enough.

$8k for side turbo is an option but would rsther do it internally. Soumds like.the only option is to to increase displacment. New p's and C's gets expensive.

Guess new rings, bolts and topend rebuild.

A bit dissapointing. Turbo.kit seems the biggest bang for.the buck. Have to convince myself to spend the money or not.

Chris
89 carrera

Have you ever seen an RPM that might be labeled a money shift? If so, you're whistling past the graveyard if you ignore the rod bolts.

[silverlock]

To expand on the questions here: do you have a power target in mind? What are you chasing? Considered re-gearing?

[Henry Schmidt]

Originally Posted by silverlock

To expand on the questions here: do you have a power target in mind? What are you chasing? Considered re-gearing?

Horse power targets are generally budget based. How many dollars faster do you want to go? Then the questions of drivability and survivability.
Gear changes are a great way to simulate horse power but the cost to change gears in a G50 can start to be astronomical. While you're in there add-on cost thousands.

[cmcfaul]

Easiest way to.get a gear change is a lower profile tire. Makes highway driving annoyimg.

Gonna do the basic top end, chains, rings and bolts, etc See if i gain anythig back.

I butchered the flywheel bolts when changing the main seal, twice. Stock or ARP?

Black Friday purchase.

Thanks

Chris

[Mr. Merk]

Originally Posted by mikedsilva

Turbo.

If everything else is "fine", add a low boost turbo setup and have an easy 300-350hp and gobs of torque.

Don't 'waste' money on anything else.

https://www.protomotive.com/wp422/product/stage-1-911-carrera-on-the-side/?v=0b3b97fa6688

Originally Posted by Henry Schmidt

I am a have fan of DFC DC 43x 109 LC.

I found that DRC has a DC43x-102 cam for carb applications. What is the 109LC? I am intrigued.

[Henry Schmidt]

Originally Posted by Mr. Merk

https://www.protomotive.com/wp422/product/stage-1-911-carrera-on-the-side/?v=0b3b97fa6688

I found that DRC has a DC43x-102 cam for carb applications. What is the 109LC? I am intrigued.

The 43x 109 is a cam John made for an ITB 3.9 I built originally running 993SS cams.
The simple change to the 43x 109 gave us close to 50 HP.
The 109 denotes lobe center. CIS, Motronic and most EFI engines require an expanded lobe center to idle and transition properly. His standard 43 112 is recommended for EFI or turbo but we were looking for something special.


Edit: The X in 43X may be an errant reference. I'll have to talk to John about the designation.

[Mr. Merk]

Originally Posted by Henry Schmidt

The 109 denotes lobe center. CIS, Motronic and most EFI engines require an expanded lobe center to idle and transition properly. His standard 43 112 is recommended for EFI or turbo but we were looking for something special.

My DRC 993SS has 114* LSA. Todd Knighton had recommended changing it to 112* for more usable powerband.

What's your opinion on this?

[Tippy]

Originally Posted by Mr. Merk

My DRC 993SS has 114* LSA. Todd Knighton had recommended changing it to 112* for more usable powerband.

What's your opinion on this?

Any dyno numbers? I have a very similar motor.

[Mr. Merk]

Originally Posted by Tippy

Any dyno numbers? I have a very similar motor.

It's not back together yet but I'd like to have it dyno'd once it's all dialed in. I will probably have Todd at Protomotive tune it locally.

Enlarged throttle body
B&B headers with 2-1 Borla muffler
993SS cams and Ti retainers
KEP pressure plate

otherwise it's a stock US G50 Carrera drivetrain

[Tippy]

Originally Posted by Mr. Merk

It's not back together yet but I'd like to have it dyno'd once it's all dialed in. I will probably have Todd at Protomotive tune it locally.

Enlarged throttle body
B&B headers with 2-1 Borla muffler
993SS cams and Ti retainers
KEP pressure plate

otherwise it's a stock US G50 Carrera drivetrain

I have a 70mm TB 1 5/8” turbo headers, 993SS cams, and KEP stg II pressure plate.

Really curious what you make.

I’ve seen 2 here make 260hp.