N/A Build

[rushtom2]

Hey there.

I'm somewhat new to these forums, and new to the 3s scene.
Before you flame me and tell me to read the N/A Bible, I'm not looking to learn the basic mods. I am a tech, and build high po cars as a career.

I had a big turbo SRT-4 prior to going 3s. I will be picking up my 3s project here within a few weeks, and will start the tear down for its all motor project. I've been down the boost road, and am going for an entirly different project, so don't tell me to go TT conversion. N20 will be considered, 3.0L motor will be staying in.

I am looking for experienced people with these motors, to help me build accordingly. I will be pulling the head apart and doing a full pnp on the head, and planing it down, as I'm looking to raise the compression as much as possible but what I do with the block is undecided. Do these motors lose power due to restrictive exhaust? Restrictive intake? Cams? I havn't been able to find anyone on here with cams on an N/A build. Is this due to initial cost, or are they ineffective?

I'm not looking for any info on beginner mods, but rather someone I can discuss more labor intensive building/tuning. These cars are rare where I live, and I have not had the luxury of ever working on one, so I'm looking for facts. I want to know A/F ratios, factory ignition timing, etc. Any serious info that I can use to help me focus on what standalone and how to build the motor since every car is different.

[speedy25]

Yoo-hooo! Look up at the top of this forum page and check out the NA upgrade bible.

-SP

[Deadlylegacy]

Originally Posted by speedy25

Yoo-hooo! Look up at the top of this forum page and check out the NA upgrade bible.

-SP

Can you read?

The exhaust is rather restrictive. Alot of people go single catback, eliminating the cat completely. Intake, K&N does no wrong. I couldn't tell you much about cams however.

These NA engines don't have a ton of potential though. Upgrade everything and it might put out 300hp. A few people have done 6g74 swaps which is a 3.5L shortblock instead. Granted you mentioned that you were keeping the 3L in.

[rushtom2]

Anyone know the average STOCK wot afr?
What about playing with the timing? Timing can be adjusted at the distributer with these, correct?

A solid tune can do wonders... I've had gains of 30+ whp with advancing the timing and leaning out the fuel curve. Does anyone know of anyone on these forums who has done extensive tuning on the n/a cars? There has to be un-tapped potential somewheres in these motors. 1.8L honda motors can pull better dyno numbers with the 10:1 compression.

[Stealthee]

You definitely need to do some research. The DOHC are distributorless ignitions and run off coilpacks.

[Purdue3KGT]

Only base models have distributors... thus being the only ones which you can advance/retard timing easily.

People have gone all-out on these engines and still not seen too many gains. The heads actually flow pretty well in stock form (DOHC atleast) and do not need too much in the way of porting/polishing. I would suggest holding off on that unless you have a flowbench to test individual changes.

Cam wise, there have not been too many cars with them because of the initial costs. 3SX is selling them for around $4-500. It is hard to spend that on something that really hasn't been proven.

The fastest N/A cars are around the low 12 second area... (Maximal) has a highly modified N2O car with direct port injection.

[Stealthee]

N2O is not NA though.

Terry has gone crazy with his set up and yes can run 12's on a direct port set up, but without nitrous the car is still about as quick as a stock TT.

NA builds just do not make sense for the money spent with these cars.

[rushtom2]

Originally Posted by Purdue3KGT

Only base models have distributors... thus being the only ones which you can advance/retard timing easily.

Silly me. I thought I read that somewheres.


I'm pulling the motor apart regadless. I do the engine building/pnp myself. The fact that labor for me is free of charge opens a lot of windows for the wallet. I don't care that n/a is expensive for the gains, because that is what a project is for.
Your certainly right on the cam one though. They can make the world of difference on some cars, but I have yet to hear of someone running them on one of these N/A.

What is the best standalone for these cars? I need something to play with timing. I see the TT guys are using eManage and EMS, but I'm not playinig with any boost on this one.

[Stealthee]

Those are basically your choices.

[Stealth_E]

Also, rather than planing the head, you might consider the higher compression Ross pistons available for the NA cars.

Ross Custom 3SX Pistons - DOHC Non-Turbo*-*Mitsubishi 3000GT*/*Dodge Stealth Parts

If you're doing any headwork, the later generation "big bore" lifters are must do upgrade as well and can be had for around $100.