Like I've mentioned in a few other posts, I'm going from a '96 Esi to a '96 TSi awd with a lot of mods. I'll be new to turbo, so I just want to get a few things straight. I've asked some newbie questions already, and have seen that on most stock internals you shouldn't really run over 8-10 psi it seems? That 18 psi on a daily basis is too much?

Does aftermarket internals include any machining done to the engine parts? I'll list some of the performance mods done to this engine and let me know if it's safe to run 18 daily, or for race purposes only.

Bottom end rebuilt: Clevite Bearings, Turned Crank, New Oil Pump, removed balance shafts, new rings, new gaskets, new Head bolts.

big 16g, upgraded intercooler piping, HKS bov, 1g TB and ported intake manifold, ported exhaust manifold to match gasket, ported o2 sensor housing, 2.5 in downpipe, hi-flow cat, greddy cat-back, 190lph fuel pump, lightened flywheel.

There are other mods done, but I tried to limit to those that would affect the engine's performance. So what are the opinions? I'm going to put on a FMIC, and then get a S-AFC and get it dynotuned. Should be some nice hp outages.

The weak links in the 420A are the pistons and rods. It looks like you haven't changed those, so you will be limited to the standard 8-9 psi. I wouldn't recommend running 10 on factory pistons and rods.


1996 Eclipse RS / 5-Speed / Aerogear Body / Coated in Magnetic Red Metallic rev.2 / T3 Turbo Intercooled @ 8 psi / More at http://home.insightbb.com/~mgalyan/
Mark Galyan - Indianapolis, Indiana

but it's not the 420a engine....is it? I thought the tsi and gst/x engines were the 4g63?

i've read that stock 4g63 internals can go to 20psi with no problems. just as long as you have adequate fuel flow you're safe. all i can say is do a compression test on the Tsi and hope it's still has good compression #'s. they're 8:6:1 so they should be at the 150's across.

Oh my bad, I didn't pay enough attention. If you have a 4G63, I have been told that they can handle well over 300 hp. Crank it up yo! :)

1996 Eclipse RS / 5-Speed / Aerogear Body / Coated in Magnetic Red Metallic rev.2 / T3 Turbo Intercooled @ 8 psi / More at http://home.insightbb.com/~mgalyan/
Mark Galyan - Indianapolis, Indiana

I don't know a whole lot about the 4g63 cars, but i hear you can run a max of 15 psi on the stock fuel system. Look into the MAF translator, people LOVE that thing. www.ramchargers.com

with stock fuel , (STOCK) you can run 15 daily, with just a pump, bump it to 20 and you will have no probs still. Once you throw in some 550's or 660's and an AFC, more like 24 to 25 on stock internals. Do not do the translater, no need on a 2g car, the reason the 1g's have problems with the stock maf is it can only read so much air therefore will fuel cut, with larger injectors and an AFC you can tune that out and trick the maf into reading less air while still getting enough fuel. One of the easiest ways to upgrade is to go to a 2g maf though, the amount it can meter is much higher, until you plan on running more than 30 psi and rebuilding the engine, stick with stock maf and AFC, you really don't need a FMIC unless you are going to run the hell out of it as well, do you have hard upper and lower intercooler pipes for the side mount though? That is a very good part to have and also the throttle body for a 1g will help out a lot. Check DSMtuners for a lot of 4g info or the 4g forums here because a lot of us do in fact have 4g63 cars.

Well it's got a 190LPH Walbro fuel pump. I don't recall what the injectors were, but they're upgraded w/o being overkill. I've noticed the fuel cut problem, so I thought removing the honeycomb in the maf sensor would solve it. I've got the upgraded IC piping even w/o the front mount. But when i install the FMIC, i was also going to install an s-afc to fine tune everything. Would the honeycomb removal on the maf sensor be enough for the fuel cut, or would the s-afc help? With the FMIC and s-afc, i'd probably do 20psi for occational highway racing and showoff purposes.

If you want to look for "frfee mods" check out www.roadraceengineering.com. Then go to the free mods or do-it yourself section. There is more than enough information there to melt your brain. Just make sure you don't melt your engine in the process.

On stock fuel stock turbo you really can't run anymore thasn like 16 psi. After that the t25 turbo isn't really running effecient anymore and is just blowing hot air.

Give us a list of mods that you have on the TSi right now. This way we can help you a little better.

lol, look at the original post above for mods =)

4g63 pistons are supposed to be able to handle up to 600 hp. its not really helpful here but it's pretty impresive

Originally posted by slodsm
with stock fuel , (STOCK) you can run 15 daily, with just a pump, bump it to 20 and you will have no probs still. Once you throw in some 550's or 660's and an AFC, more like 24 to 25 on stock internals. Do not do the translater, no need on a 2g car, the reason the 1g's have problems with the stock maf is it can only read so much air therefore will fuel cut, with larger injectors and an AFC you can tune that out and trick the maf into reading less air while still getting enough fuel. One of the easiest ways to upgrade is to go to a 2g maf though, the amount it can meter is much higher, until you plan on running more than 30 psi and rebuilding the engine, stick with stock maf and AFC, you really don't need a FMIC unless you are going to run the hell out of it as well, do you have hard upper and lower intercooler pipes for the side mount though? That is a very good part to have and also the throttle body for a 1g will help out a lot. Check DSMtuners for a lot of 4g info or the 4g forums here because a lot of us do in fact have 4g63 cars.

Well as I've found out, they're stock injectors, but an upgraded pump. So I figure I'll upgrade the injectors, and the rail while it's out, then I'll add the FMIC and try and dynotune an s-afc. I already took out the honeycomb on the MAF cause it was causeing fuel cut. It's also got the 1g throttle body with ported elbow and intake manifold. So, i guess the next question is, S-AFC I or S-AFC II? And where can I buy either for cheap?