N/A performance

[Jrad0425]

Ok, before the flames begin I will say this outright... If you want insane power you have two options for about the same price... sell your current N/A and buy a well maintained turbo OR go with the unholy LS1 swap... now that thats out of the way here are some inexpensive modifications for the N/A owners out there that are not crazy for either of those options.
I currently own an immaculate 84 944, After sorting through the deadly alarm system (exposed hot lead under the dash) and pulling that and some other weight out of the car, discovering my autothority chip and adding a throttle cam (no added power but it feels like it) There is a definite difference with the car and its a lot more enjoyable to drive, I have talked with my local P-car mechanic and auto-x driver who has an "extreme N/A 944" we discussed possible HP gains and such and what different things cost, the dreaded cone filter came highly recommended by him, and possible exhaust upgrades.. and not to mention the all important full tune up that will make an immediate difference to any car... Lets take a min and think about price. Chip about 250 if you go with FRWILK, throttle cam 20-30, tune up... cost of parts 30-??? look into plugs and wires... and cone filter, 5 dollar adapter plate and 20-30 from K&N exhaust 300-1000 depending on what you do and one can probably pick up about 30-50 hp overall, which for the price is a pretty nice gain... then you can go crazy and dump a NOS kit in add 100 HP and a blown engine... (no i didnt do that)... just a few ideas for the N/A owners out there... i know i didnt mention suspension but there are a million posts about that... Add your own ideas for some performance gains Im interested to see everyones opinions and ideas
-Jrad

[Techno Duck]

30-50hp from chip, intake, plugs, wires, tune up and exhaust is way to generous. I wouldnt count on more than 10hp. And the power gained from the plugs and wires is likely recovered lost power from worn / old components.

There are dyno proven results floating around of the FRWilk chip with only a 2-3hp and 3-5ft-lb gains.

A cone filter is debatable, i have never seen proven results with a cone filter. Anyone who says heat soak is an issue is correct, if your sitting at idle. In motion the engine bay is at or near ambient temperature. Dont believe me? Go for a drive, stop, pop the hood and stick your hand on the intake manifold...cool to the touch.

Removal of the cat is said to be good from anywhere between 5-10hp depending how clogged your current is.

I went through all of this on my old n/a. My car dyno'ed at 136whp 3 months before i sold it on a load type dyno with just over 100k miles on the clock. My car was pretty darn well sorted in my personal opinion. I was also running Magnecore ignition wires, rebuilt cylinder head (5 angle valve job), drilled airbox and a full 2.5'' exhaust (test pipe), FRWilk chip and a/c delete. If you account for 15% drivetrain loss i was making somewhere around 155bhp. Stock rating was 147bhp from the factory. So all of that was worth 10hp or less.

I will say if you want to get a good start on increasing power, you need to look at the cam first. I personally think one of the reasons free flow intakes and exhausts have little to no effect are the lack of valve overlap with the stock cam. Besides, dyno proven cam grinds have shown 12-15bhp increase over stock with a decent exhaust with mild grinds. The problem with cam's is basically the power you gain from them is taken from somewhere else in the RPM range. So usually you are gaining peak power and losing low end or mid range power. Basically i think with a decent cam it will improve all other upgrades done on the intake and exhaust side. I never actually got to buying one though.

If you look at the Spec944 racing guys with freshly rebuilt motors, i think the strongest ones are in the 135whp range.

If you want to improve overall performance, start thinking about stripping weight out of the car. I had my '87 down to the sub 2700lb range and still had the 55lb each leather sport seats in the car. It was a great deal of fun on the track.

The biggest problem is there are no PROVEN results with modifications done to the 8v n/a's. Hardly anyone is willing to take the plunge and buy the expensive parts which have no proven gains and even fewer are willing to pay the money to have it dyno'ed. So its sort of a double edged sword in that respect.

[fast924S]

No way in HELL are you going to see a 30-50hp GAIN from tune up and a airfilter/chip, MAYBE about 5hp total.

With these engines You wont see more than about 5-10hp MAX with just bolt ons, You gotta get inside to make power.

As techno said, First place to start is the CAM, I just got a JM camshaft and will be intalling it soon. Jm said its good for 12-15hp from 3-6500rpm. The stock cam doesnt have much overlap and is very mild. Next thing I would do is PORT MATCH EVERYTHING. I noticed from doing my current rebuild that Some ports DONT match perfectly with about 1/8 to 1/2 a inch of over hang, Same for the throttle body. Then the next thing would be to BUMP up the compression ratio, Ditch the 9.5CR and go with the 88 10.2 or the euro's if you can find them. Then a good balance and lightening of the bottom rotating assembley and a lightweight flywheel. FRom there have some head work done (mild or wild). Install a good header and catback exhaust (no cat)
After all that I would then move to electronics, DItch the crapy AFM and go with a MAF or Map setup. Have a custom chip made or a standalone setup installed for the ECM. The factory ignition timing can be better and so can the fuel maps.

So all that will get you a fun little STREET motor with a MILD build and cost about 2-3k in engine work and parts ALONE. Now you might be at about 180-200hp

[Razorback1980]

^^ what they said. I guess if you had a rotor like on a post about a week ago, you would get a 30hp gain...but your car would have to barely run to get that type gain with no work. Good to be optimistic I guess.

[Jrad0425]

i should have made myself more clear, im talking about a used engine and im not saying 50 horsepower over stock... and also Im running an autothority chip which has a proven 10-15 hp gain, If we look back at the beginning of the post there is no magic way to make a N/A a monster unless your N/A turns into a N/A LS1 ... in which case the N/A would be pushing about 300 hp and you could really fly.... Bottom line is for all the N/A guys out there, these are some ways to improve on an spectacular car without breaking the bank, your gaining more in the seat of your pants then overall HP gains.. I think we can all agree that even if the HP gains are not amazing and it "feels" faster its more fun to drive

[Techno Duck]

I would LOVE to see a dyno sheet that proves a 10-15hp gain from the Autothority chip, or ANY chip for a n/a for that matter. What Autothority claims (or any chip maker for that matter) is probably going to be far different from what your real gains are.

[speedracing944]

Or you could do what blown944 did and toss a M-90 supercharger on it and get some good HP.

Speedy

[fast924S]

No chip for a NA is going to give 10-15HP. Big chip companies and some air filter companies claim BIG HP numbers. Most of the time its false, Or its what they got from ONE car, may not even be your make/model. Dyno sheet with the chips and prove it wrong, I would love to see a NA chip push out a extra 10-15hp.

Only way to get big PROVEN numbers is to built it/or swap it or add power adders like a sc/turbo/nitrous.

To get better seat of pants feel, Yes a chip can do that and so can exhaust/intake mods. Usually from moving the power band around

[Taz's Master]

When looking at power gains, you need to be careful. How do you measure your gain?

Depending on how you measure your gain you could easily have a 10-15hp gain and have the car accelerate slower, measure it a different way and see a 2-3hp gain result in a noticably faster car.

Look at a dyno graph, it is totally acurate for a mfg to say that their chip has a demonstrated 10-15hp gain, if at say 2300rpm it spikes more power over stock at the given rpm, even if peak power is lower than stock. Don't think that advertising like that isn't out there. The result is that you have 10 extra hp, but your car is actually slower.

But if you define hp as only peak hp, you could really miss the boat. Again looking at a dyno graph you need to look at area under the curve, a 3hp gain over stock peak hp, could be much more significant if there is substantial gain at other rpm's in the power curve. 3 peak hp could actually be a noticably faster car if (like our 4cyl Porsche engines) the stock power curve is not smooth and fat.

Overall I agree with what has been suggested here, namely: Improving cam timing, fuel maps, air metering, reducing backpressure and increasing compression, while getting the long block balanced and blueprinted will result in decent gains. So will forced induction, nitrous, and SBC swap. Nothing is cheap, and all the routes have their benefits/downfalls.

Personally I want to port match the larger '89 engine, and use this board's resources to help me find a reliable fuel system for a blower set-up. But first I need to finish building my house, buy the wife a newer family hauler, get the 944 painted (or find a suitable 944 with a bad engine for cheap), college for the kids...