Enlighten me on my next engine upgrades for this summer

Coelacanth

Active Member
Joined
Jul 7, 2014
Hi Guys,

The last few seasons, I've upgraded my intake (my own custom-made 3.5" intake with LS1 MAF, the 3.5" tube goes right up to the stock turbo where it reduces to 3"), fuel pump and hotwire kit (see signature), AXiS interface and chip for 93 octane (I'm still running stock 28# injectors). The car is really waking up. I'm hoping you all can share some advice on where to go next, as I have a little money ($800 or so CAD) to put into the GN this summer.

I'm getting 60# injectors and a TT 5.7 chip from a fellow member that was burned for an identical combo, except it's not AXiS-compatible. It should run fine but I'll lose the spark and fuel adjustments of the AXiS. I'll send Eric my existing chip to reprogram it, but that'll happen later.

I'm happy to buy used if in good condition, it saves me money and helps the community recycle their unused parts. Here are some plans, feel free to share advice and suggestions.

-RJC Power Plate to even the flow to the cylinders and reduce knock. I eventually want to have my throttle body & plenum ported, but that might not be until next year.

-RJC Boost Controller. Will this install with no mods to my existing stock turbo & wastegate? If I plan to upgrade to a TA49 turbo, will the boost controller need modding then?

-Billet vacuum block...mostly cosmetic, but might reduce vacuum leaks, and will add a port for when I eventually convert to vacuum brakes.

-With my intake addressed, at some point I'll need to work on the exhaust, but that can be quite pricey. I'm looking for a 3" downpipe but I need to be educated on the options; test pipes, dump pipes, etc...I'm not concerned about emissions here in Canada, but I should probably keep the cat. If I upgrade my stock downpipe with a 3" unit, will I need to also upgrade the rest of the exhaust system? Will the 3" DP bolt onto the existing exhaust, which still looks solid? Eventually I'll upgrade to a SS Pypes 2.5" exhaust. Or should I just wait and do the DP and exhaust together?

-I'm considering a turbo upgrade to something like a TA49...keeping stock appearance isn't important to me, I'd just like a decent performance upgrade that's not too expensive. Something that'll bolt on without much or any subsequent modding. A turbo with a 3.5" inlet bell would be sweet, because then I wouldn't need the 3.5"-to-3" reducer.

I'm pretty much open to your suggestions and advice. What direction should I go for my limited summer budget? Thanks in advance.
 
If emissions is not a concern I would definitely ditch the cat and use a test pipe in it's place.
I've ran 10's through a Hooker cat back system & from what I have read the Pypes is similar.
I had a Kirbans 3" downpipe and ported the stock exhaust elbow with a TE60 - worked surprisingly well and affordable.
Steve Monroe bored my throttle body to 62mm w/the 1/2 shaft mod. Reasonable and I port matched the plenum myself.
I've ran a RJC boost controller before - simple and it works. Shouldn't be a problem with a larger turbo. I believe I pulled it apart and stretched the spring out for more boost.
 
Thanks, DSEROVY, good info there. I saw this 3" downpipe from Kirban's, I could actually afford that this summer. It's a 2-piece, should install easily enough, just needs a bit of work to fit to the existing cat, from the looks of it:

http://www.kirbanperformance.com/product/326/STAINLESS+3"+Bolt-In+DOWN+PIPE+and+CLAMPS+(2)+#6568.html

Does anybody have experience with this unit? I have stock exhaust headers and from what I've read, for my high- to mid-11 second goals, there's no need to replace them with headers.
 
Hi Guys,

-With my intake addressed, at some point I'll need to work on the exhaust, but that can be quite pricey. I'm looking for a 3" downpipe but I need to be educated on the options; test pipes, dump pipes, etc...I'm not concerned about emissions here in Canada, but I should probably keep the cat. If I upgrade my stock downpipe with a 3" unit, will I need to also upgrade the rest of the exhaust system? Will the 3" DP bolt onto the existing exhaust, which still looks solid? Eventually I'll upgrade to a SS Pypes 2.5" exhaust. Or should I just wait and do the DP and exhaust together?

I suggest to make it easy on yourself, get a test pipe or dump pipe along with whatever downpipe you get if possible as downpipes are different lengths. Making a test pipe is farely easy if you have the means.
Anything with the 4 bolt flange will bolt to the stock or aftermarket exhaust.
If insisting on a cat, get one sized to fit the downpipe to reduce restrictions.

Something to keep in mind about turbo selection is the TE series (44) can support a few more hp and requires a longer coupling hose than the TA series (49) if your MAF pipe cannot be relocated a bit.

If interested I have an RJC Racing manual boost controller (minus the hose) that I used for mock up I will send you, just pay shipping.

Cheers,
George
 
That would be awesome, George! I'm in Canada, but I'll be glad to pay the shipping. I'll send a PM.
 
Update: Here's a look at my next purchase for this summer's GN budget. I'll also add body bushings, but I first need to check which ones my car is missing. This list is in addition to a TT 5.7 chip and 60# injectors, MSD wire set and George's boost controller.

I have the stock turbo and exhaust and some questions about that 3" Kirban downpipe. If i understand the description correctly for that item, it replaces the stock exhaust elbow, thus I won't need to port my existing elbow...is that right? And will it bolt right up to my existing exhaust/catalytic converter?

Any other comments or suggestions, before I call in the order? Thanks guys!

Kirban Order 4_Braces.JPG
 
Being on a budget the only thing on the list I would get is the power plate and save up for a good 3" downpipe like the RJC one or similar and get a dump pipe or test pipe with it: http://rjcracing.com/product/downpipes/. Used ones come up for sale now and then too or at Buick events.

An alky kit would give you the most bang for the buck as far as performance (much better than upgrading turbo and keeping it on 94). A dutt neck stock intercooler or a dutt neck (if you can find one) mod yourself is a cheap upgrade too. Upgraded intercoolers are pretty expensive.
 
Thanks, murphster. I plan to add alky next year. I've read up on those dutt necks but they're pretty hard to find, and a complete intercooler isn't in the budget or plans for the near future. Why do you suggest a "good" downpipe? What would make it significantly better thant the Kirban unit? I want something that will bolt up with minimal hassle between my stock turbo and exhaust.

Would you guys recommend adding the alky kit or a bigger turbo, for next year?
 
Getting rid of the stock elbow is a main benefit of the aftermarket downpipes. Plus it will have a bigger puck that could benefit you with better boost control with an upgraded turbo down the road. And it looks a lot better. Plus, get the test pipe or dump pipe with it and it will bolt right up to your exhaust with no issues. A 3" band clamp works well to connect the downpipe and test/dump pipe.

There is no comparison in performance between a stock turbo on alky vs an upgraded turbo on 94 on a stock setup. You won't see much gains on an upgraded turbo over stock unless you can turn up the boost using alky, race gas, E85, etc...
 
I'm not much of an exhaust expert, so thanks for the info. Does the test pipe replace the catalytic converter?
 
Thanks, murphster. I plan to add alky next year. I've read up on those dutt necks but they're pretty hard to find, and a complete intercooler isn't in the budget or plans for the near future. Why do you suggest a "good" downpipe? What would make it significantly better thant the Kirban unit? I want something that will bolt up with minimal hassle between my stock turbo and exhaust.

Would you guys recommend adding the alky kit or a bigger turbo, for next year?

The Kirban's 2 piece 3" downpipe ($199.95) bolts to the existing elbow which is the restriction.

The one piece 3" downpipe ($415) is a TA performance unit and does replace the stock elbow and with the test pipe replacing the catalytic converter will bolt up to stock or aftermarket exhausts.

IMG_4637.PNG
 
Guys, if I replace the cat with the test pipe from Kirban's part number 7627, which I ordered last week (but is on back-order), will that throw an O2 sensor fault code like on modern cars? Or can I just delete the cat and call 'er done?
 
No, it will not throw an O2 code, get rid of that plugging up pos convertor, and call it good, move on to the next, open up the check book, and spend a little more for “another” gadget, gauge, head gasket, radiator, lol. The list goes on and on, but it sure is blast!!!!!!
 
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