HELP: 3grand I/C exh.+ car is slower!

[Brad-ManQ45]

Let me preface my following remarks by stating that I do NOT have an intercooler.

 

I had a T3/T4 hybrid w center warter cooliing installed on my '83 ZXT at 134000 miles, with a simple boost controller.

 

At the same time the shop farmed out the exhaust to a good shop that put on a 2.5" from the cat back to a flowmaster muffler.

 

The car was quick (10 lbs boost).

 

The Flowmaster was TOO LOUD. When looking at the exhaust I noticed no mandrell bends (against specs when I ordered the work).

 

I took the car back to the mufffler shop and had 3" mandrel bent tubing from the downpipe back and a 3" cat and sraight through oveal dynomax muffler put oon it.

 

The car sppooled faster and hit harder this way. I have problems with boost creep - occasionally hitting 15 psi (no detonation because of the T4 compressor section).

 

I don't think your problem is the exhaust.

[jeffp]

Having done all that you have done to your car and more, the labor costs can eat you alive. I decided long ago that if I was going to do these mods I was going to do them myself. So that is what I did.

Bandsaw= 195.00

welder= 290.00+150 for the gauges and controller.

So with that in my garage I was ready to do work.

I went with mandrel bent pipes in steel, no to heavy, and 10.00 for each u bend. I needed 3 ubends and 1 jbend to complete the job.

all total on thwe second set of pipes was about 250.00 with a new coupler and powdercoating. I saved tons of money, but I spent it elseware.

My first proto exhaust cost me about 450.00 and then I had it made mandrel bent at Bassani Exhaust. That cost alot but it was worth it.

So it is not cheap to have this stuff done. I have tried to do most of the work myself, I cant imagine how much more I would have paid for all the work.

So yes it was expensive, but that is what you will pay to have someone do your work for you, sucks yea, but that is what you can expect.

 

Lastly, if you want to see what the turbo will do for you, I am bnot to sure of the turbo, but remove the line from the compressor housing, plug the holes(or the hoses) and get the waste gate actuator signal after the throttle plate, like with one of the fittings on the intake, tee it and you will get you boost back. Just keep an eye on the boost creep and all that stuff. That will get the boost back up for you. Or you could go with a controller and control the boost that way.

anyhow, hang in there, your car will get to where you want it to, I'm just not sure about your wallet, or my wallet for my little project LOL

[Tony D]

I'm in the same boat as JeffP! Labor will eat you alive. I do not begrudge a gent making a living, and having run a shop, I realize $65 hourly is really a low rate for fabrication.

I decided to buy a bandsaw after seeing how well the Harbor Freight unit Jeff uses does, and do my own thing.

The way I look at it is 24 hours of labor is one man working for three days (also including running for parts, etc...) so while a custom shop might do it in 6 hours, they also most likely will charge $120 for the labor (like they do here in L.A.) A decent fab shop will charge a higher price because like stated, they have all the goodies to do it quickly, and their hours are all they have to make money on, so the question becomes do you want it done in 6 hours at $120 an hour, or in 12 to 20 hours as a competent fabricatior works out the setup, and goes at it from ground zero with you paying for setup and development of the final product.

Any way you look at it, labor kills. So I don't think you are out of line on the charges---but I would question what took him three days to do. One of the reasons I use steel tubing is it doesn't require the setup like aluminum, and I can finish it with my oxyacetlyene rig if I so choose (comfort level).

Suggest your fabricator use pre-bent mandrel bends like JeffP suggested. They are cheap from Burns Stainless (as well as several other places) and really cut down the charges for custom bending.

If they mandrel-bent the tubing all together, then that is another story, and the cost is right in line with what they charge out here.

Don't get discouraged. And relocate the boost sensing line for the turbo as stated---you have pressure drop now across the system (probably 1.5 to 2psi) so you will want to make up for it. Good luck on the project.