Any potential problems with running this modest set-up?

[91Bomb]

I want to run 14 lbs on 13g with:

390 injectors
m/t cams
small a/t ex man
stock exhaust with TP
real boost gauge
no logger
no egt
fuel pump re-wire
K+N w/ no air can


UNSURE IF THESE ARE NEEDED:

egt
bigger ex man
bigger DP
450 injectors
bigger turbo

I'd like to run this modest set-up and need to know whether it'd be completely safe or not this way.

 

[92awdgsx]

That should work fine with no problems. Cams might be a little big, but it shoud work.

 

[91Bomb]

I think I would get the egt gauge to be safe and I guess since a set of m/t cams are so cheap I could try them and if I'm not happy I could easily change them back.

BTW, can you mate a 13g to a 2g manifold?

 

[Wizard]

Yes, it bolts up...but the inlet on the 13g exhaust housing is is much smaller and offset slightly. I used a MT manifold with just the lip cut out and hogged out the inlet to 6cm size. Then ported it gradually.

I was running 390cc, 13g, rewired stock pump, MT exhaust cam retarded 1 tooth, intake AT cam straight up. 3" exhaust, K&N, free mods and timing bumped to 9-10deg. BTDC, 225/50r16 tires and stock tranny and convertor. Ran 13.8 at 100.

Wiz

 

[91Bomb]

Yes, it bolts up...but the inlet on the 13g exhaust housing is is much smaller and offset slightly. I used a MT manifold with just the lip cut out and hogged out the inlet to 6cm size. Then ported it gradually.

I was running 390cc, 13g, rewired stock pump, MT exhaust cam retarded 1 tooth, intake AT cam straight up. 3" exhaust, K&N, free mods and timing bumped to 9-10deg. BTDC, 225/50r16 tires and stock tranny and convertor. Ran 13.8 at 100.

Wiz

What gain do you get by running your MT exhaust cam that way compared to the AT cam and do you lose anything on the low end with it and do you think an unported AT ex man at 14 lbs is OK and does the maf need hacking?

BTW, were you using a logger and what boost were you running for that 13.8? Using Pump gas?

Basically I'd want to run 14 lbs every day all day without any problems. I really don't want to get a logger for a few reasons but I guess I probably should. If 13g gave out I'd either get a used 14b or new s16g and mate it to a 2g manifold and run it at 15 lbs. I'd stick with stock i/c + rubber intake hoses unless some hard pipes became available for real cheap etc etc. I'd use the egt gauge to keep an eye on things and I'd compression test periodically. I'd want to keep things fairly mild and simple and 15 lbs would be my limit as the car would never see the track and funds are very limited

 

[Wizard]

www.straightlinespecialties.com Cheap hard pipes.

I was running pump gas on 13.8.

No logger then, 16psi.

Problem with 13g is not the compressor, it actually flows as much as a T-25 or so. But the exhaust housing and exhaust manifold are incredibly restictive. The car felt totally different with a 6cm and ported 1g manifold. Much better top end even without boost. didn't feel like I had the wall I used to. Plus, the 13g couldn't hold 16psi past 4500-5k. It would start dropping off quickly. Down to 10psi by 5500. Mostly due to exhaust side.

The cam swap was just an experiment. I'm sure the differences were so minor that even on a dyno I probably wouldn't have seen any change. The cams are so similar in grinds. They mostly help in the top end where the slightly longer duration and lift would actually hurt low-end performance. Which is where the 13g was decent. Up above where the cams were starting to actually show a gain the turbo fell off anyways. Leave your cams alone until you upgrade the turbo.

MAF was a 1g with the lower HC out and screw backed flush. K&N, 16psi all day long on pump.

Wiz

 

[91Bomb]

Thanks -- it's hard getting good info about the 13g. What you're saying is the 5cm exhaust housing is very restrictive so I can get a 6cm from a 14b and mate that directly to a 2g manifold without changing anything else? Shouldn't I get 14 lbs boost to redline though if I want to? Why was your boost falling off to 10 lbs so early? Mine seemed to hold at least 12 lbs to redline with 5cm housing + A/T manifold. Did you eventually go to a 14b or s16g and if so what were your impressions on spol-up time and turbo rush compared to the 13g because I'm thinking I'd rather have 14 lbs on 13g than 15 lbs on 14b IF 13g is going to respond quicker and lower. Irregardless of turbo size am I better off using the a/t cams if max boost is only 14-15 lbs?

 

[Wizard]

The 6cm will not fit the 13g cartridge. I went to a 14b with 6cm and ported MT manifold.

Higher boost levels will be harder to maintain at higher levels. Especially with such a small compressor and restrictive turbine. By porting out the exhaust housing, I saw a decent increase in RPMs before it fell off. It is possible to hold 12psi to redline, but 15+ will fall off with same setup.

The 14b did spool slightly slower. I get full boost on 13g by around 2500. 14b waits until 3k or so. But much stronger pull from 4k+. When I went to the 14b it was a bit harder to launch without lighting the tires up. 13g was very easy to hit 2.0 60ft and not spin. 14b loves to light them up right at about 3k or so. I still have the AT intake cam. And it has done pretty darn good in my book. But new setup is far away from 14 and stock cams.

BTW, the 13g exhaust manifold and turbine housing is known for cracking badly and quickly, due to the small size. I still have a uncracked mild ported 13g turbine housing. Let me know if you ever need it.

Honestly though....consider doing a simple 14b/6cm/1g or 2g manifold/450cc swap. The performance change was more than worth the slightly slower spool time and it can all be done for next to nothing.

Wiz

 

[91Bomb]

The 6cm will not fit the 13g cartridge. I went to a 14b with 6cm and ported MT manifold.

Higher boost levels will be harder to maintain at higher levels. Especially with such a small compressor and restrictive turbine. By porting out the exhaust housing, I saw a decent increase in RPMs before it fell off. It is possible to hold 12psi to redline, but 15+ will fall off with same setup.

The 14b did spool slightly slower. I get full boost on 13g by around 2500. 14b waits until 3k or so. But much stronger pull from 4k+. When I went to the 14b it was a bit harder to launch without lighting the tires up. 13g was very easy to hit 2.0 60ft and not spin. 14b loves to light them up right at about 3k or so. I still have the AT intake cam. And it has done pretty darn good in my book. But new setup is far away from 14 and stock cams.

BTW, the 13g exhaust manifold and turbine housing is known for cracking badly and quickly, due to the small size. I still have a uncracked mild ported 13g turbine housing. Let me know if you ever need it.

Honestly though....consider doing a simple 14b/6cm/1g or 2g manifold/450cc swap. The performance change was more than worth the slightly slower spool time and it can all be done for next to nothing.

Wiz

So the 13g with unported t-housing won't mate to the 2g or 1g m/t ex man?

Thanks but I have 2 - 13g t-housings. That lower spool does mean a lot to me though as I don't brake boost and rely on a rolling start. My concern is really whether the a/t ex man + 13g is just too small to run 14 lbs since it was designed for 10 because I wouldn't want to cause excessive pressure to build-up by trying to force too much exhaust through those small outlets. Like I mentioned I'd at least have an egt + real boost gauges to look at and I guess if I was to get a logger I'd be more than able to answer these seemingly retarded questions on my own

 

[Wizard]

It'll mate to a 1g MT or 2g manifold, but you will need to gasket match the 13g turbine housing to the opening of the outlet of the exhaust manifold. It is very different and if you don't match it up you'll get some nasty reversion. Like putting a 1g throttle body on a 2g intake without porting the opening.

Wiz