DrZ1

I have been noticing my vaccum at idle has been less, I blamed it on my hose clamps which needed changing( I have been putting off since I plan to install MAF soon) used to be 18-19 to 16-17. Yesterday I changed my A/C condensor and cleaned out intercooler and noticed now it is at 15. Last night I changed the hose clamps, w/ no change.

Today I plugged the ehaust w/ cap( w/ air connector) and ran 15psi of air from tail pipe. I could hear a leak, and could feel a leak at bottom of crossover pipe at heat sheild, this is the section that mates to the header. This was the only leak I could feel, but think there may be more. I will try to find a shop that will preform smoke test.

Questions

Will this affect vaccum?

Will pressurising the exhaust also pressurise intake?

Best upgrade for crosssover?

Thanks
Steve

Darwantae951

SFR makes a two piece cross over (secures with a v-band clamp right before it angles up to the turbo) which would make oil pan maintenance a lot easier. It's kinda pricey tho. He has the best exhaust parts on the market so you'll be getting your moneys worth. I can take pictures of it if you like, as I have one and haven't installed it yet.

-Darwin

DrZ1

Yes that would be great, I thougt the 89 S crossovers were 2 piece? Any different then 86

Thanks
Steve

Darwantae951

A "Porsche" two piece xover means that the wastegate tie in is the "second" piece. A SFR two piece crossover looks like this:

DrZ1

Any performance advantage w/ SFR cross over. I plan on running 15-16 psi stock injectors, MAF and upgraded turbo set up for eairly boost.?


I just did soapy water test and I have a leak at the 3rd runner. Does this mean I need new gaskets or new header?

Thanks
Steve

Darwantae951

Where is the leak coming from? Is it coming from the header itself or is it coming from between the header and the head? I don't think there is much gain with just switching a crossover, but if your headers are bad he also makes stage 1 and stage 2 headers. Depending on what turbo you go with, you may have to call Tim at SFR and make sure to get the correct turbo flange.

Darwantae951

P.S. with stock injectors and 15-16 psi of boost you'll probably be close to 100% duty cycle. Might think about upping to 52 or 55 lb injectors.

billthe3

I'm running 18 psi with the stock injectors and I'm pretty damn sure I'm not near a 100% duty cycle. Someone correct me if I'm wrong, but I don't think you need to upgrade your injectors until you start getting into the mid 300hp range.

Keithr726

I'd say you were pushing it. You have a k27/8, maf, 3bar FPR right? At 18psi that thing must pull nice

https://rennlist.com/forums/showthre...tock+injectors
https://rennlist.com/forums/944-turbo-and-turbo-s-forum/193296-determining-brake-specific-fuel-consumption-for-a-951-a.html

Darwantae951

My comment was based on what John Vitesse had informed me.

billthe3

27/6. Sure doesn't seem fast... Too many damn things wrong with it.