I was hoping that i could fing out what the going price is for a plenum/injector housing/intake + fresh calibration chip would run If itake parts off myself. This is not An ideal situation for a proper tune but i will live with it. I have quotes from the big guys want to see what other members might have paid

 

about $200 bucks if you do it youself...

Grinder-$50
Bits=$25
Flap wheels $35
WD40
Gloves
Paint
Gaskets:$70
I have done three of them..mine, Katerdons, and CCMANOs


LGAFF
92 #234
90 #966

 

Jeffvette and locobob did mine. All I can tell you bro is you get what you pay for. If you have looked at the forum for the latest porting projects its a bucket load of work, time and tools. GC

 

Jeffvette and Locobob also did mine. They do phenomenal work for a very reasonable rate. I highly recommend you contact Jeffvette.

 

 

WELDING! (Or, at least I have to consider that too.)

I spent a LOT more on bits (I may never use again) until I finally got put onto the SE6. No more welding.

Something else...I'm actually having fun doing it! That I didn't expect, but each "hole" is that much closer to some serious fun.

As for the chip, my Marc H chip was $475 with all "the goodies" in it:

fans (plural) come on at around 200ºF
the high idle is addressed
no backfire with headers
Secondaries on alla time (above 1% throttle)
spark advanced for premium fuel
spark knock re-calibrated
calibrated to run best at higher temp (than stock)
fuel for 55 or so more hp. (top-end (sans heads) porting w/ headers tune)

P.

 

Thanks for the replies. Myself before I do something I over investigate it.
I have quotes from all the big guys with re sized gaskets Fresh calibration
ect. There is a much bigger difference in price then I had thought. Yes you do get what you pay for.
I have a set of the NOS Injectors would be a good time to do those as well. Crazy thing is car is fine now as far as power, Holds its own against cars costing much more.

 

You can contact JeffVette at http://pnwzr1.com

Tomcat74
91 ZR1 #906

 

Pete is also I good resource, I am willing to do one for about $800.00, but that is porting only/paint..........also I have full time job so I can only do it when I have the time....the pros knock them out pretty quick.

I would think Pete would give you the best bang for the cash.

LGAFF
90 #966
92 #234

 

Thanks for reply. What kind of improvement could I expect from porting the [penum.injector housing ect

 

My car has 391rwhp with....

headers
no cats
X-Pipe


I have yet to get it tuned.

Video of the dyno run on you tube and has been posted here.
http://www.youtube.com/watch?v=8Y4Re5TqIw4

LGAFF
90 #966
92 #234

 

On a 91 with porting to the Plenum, Injector housings and head match porting about 25hp to the rear. With Longtube headers add another 10hp total in the 35hp min range with more with matching tuning to calibrate for the new mods.

Also another pitch for Jeffvette he offers about 20 different powdercoating painting options colors/flavors if you looking for something different. PM him on the registry if interested.

 

...last time I dropped by Marc H's shop. In fact, I believe his web page goes into that question in stages - worth having a look.

http://www.zr1specialist.com/HAT%20W...20upgrades.htm

But, back to your question, he says about 30 for the porting alone for a 90-92 engine.

I'm porting the top end, port matching the heads, (porting heads next winter's project, plus cam re-grind), LT headers w/ 3" exhaust, X pipe, adding a chip. Mark has some dyno graphs with pretty much the same setup showing the power curve flattening out (vs. rolling off) above 6000 and remaining practically level to 7000. RWHP is in the 390 range. I also intend to remove the secondary hardware completely, and for that I think he said it might be worth another 5 hp...maybe. (But, hey! 5/30 for the plenum/IH is another 16+% increase over porting alone, so why not?)

All that said, Mark also said the biggest pop for the money is going with a 4.11 gear. It adds another 17% torque in every gear and makes 6th usable at normal highway speeds. (Why not both???)

Skooze me. I hear my die grinder callin' again!

P.

 

You will definitely notice the difference. The horsepower gain doesn't sound like much, but the way the engine runs and breathes is another level.

But...the actual porting isn't a DIY job to experiment with. My son tried it and he is an experienced engine machinist with plenty of experience on other cars. I ended up sending my stuff to Corey Henderson who did a great job, then up to Jeff for powdercoating. Locobob helped me put stuff back together.

You might look at doing a CCT replacement at the same time. They are expensive little buggers, but they do wear out and need replacement eventually. If you can still get them (?).

 

Thank you for reply Pm sent

 

Anybody feel this way>>>>Yes, I've ported my plenum and injector housings... The first time I went into the plenum, I simply took out the casting marks and port matched the plenum to the IHs... My Z went from 318 RWHP to mid 340s on the porting alone - roughly 25 RWHP gain. After adding headers and adjusting the chip, I made 372 HWHP at SGC in 2004. After seeing a few other porting jobs from some of the known porting guys, I decided to go deeper and siameese the plenum and open up the IHs to 36mm. While I have not dynoed the Z since my last round of porting a few years ago, I believe I've gained quite a bit more RWHP, but at the expense of my mid-range torque. Looks great on paper in that I could never use all my mid-range torque with the 4:10 rear without spinning tires. Now I have a different "problem"... I don't spin tires very much in the mid RPM range, however the rear tires break loose in the upper RPM range.... so at 55mph, I lose traction. Seat of the pants, it is much faster in the upper RPMs, but I sure do miss the low/mid RPM torque. I may be able to work it more in the chip, but have not had time for it... Before you get started, you need to ask yourself what you want from your Z.... Believe there is some give and take with every mod. I've attached a few photos taken along the way.... I used my trusty die grinder, the bits in the photos, and my homemade 36mm porting ball... the red line around the ball was made with a red sharpe and left a mark exactly where I needed to grind to make a uniform 36mm port job. ## COPIED POST

 

Porting should be tailored to both the driver and car. On the early motors it is possible to pick up 20+ rear wheel HP with no loss of low and mid range torque. This is the standard porting job I do for most people. I don't siamese the runners, the ports are generally opened up to 36mm but taper down toward the head in the injector housing primary ports. Most folks are happy with this level of porting, solid gains with no downside. Now if you get crazy with huge siamesed ports on a stock size motor you can expect to lose a little mid range torque. It shouldn't be a real big loss though, I think most people would have a hard time feeling the difference.

Here is a dyno graph of my 368: before with moderate porting and after with an agressive B port siamese job. As you can see the motor lost around 10ftlbs in the mid range but picked up substantial power above 6K rpms.

 

Someone is doing a killer porting job with documentation and pictures on the net (Hint)

 

don't just think peak hp improvements. the area under the curve is what makes the car faster. the top end on the lt5 really improves and the power band improves with the top end porting and headers.

best bang for the buck, and yes, make sure you do a decent flowing exh and 4.10 gears too, and throw in a short throw shifter of your choice. modest investment, smoking fast car!

 

Here is another example for you: fairly stock 91 before and after with a milder porting job. Note that there is no loss of low/midrange torque and gains start shortly after 4K rpms.