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coolant loss on p/s. f/p or ????

The restriction is probably just to lessen pressure in the heater core. But dont you have two heater cores or something like that? If you have two heater cores you could use more flow anyway. Maybe it will keep your engine cooler too having more flow to the heater cores.
 
wouldn't that be a good thing. more flow carry away more heat. BTW matt do your like you exh. ? did it help lower your egt and how much louder than stock is it.

I think its a good thing, but if you remove the restriction in the xover oriface, you will be lessening the flow into the PS head? The head that is right next to the turbo to boot.

Is it enough to matter? People run it and don't seem to have problems....

Exhaust is great! Good price, good fit. I painted it black grille paint and 1 salty winter later its still black. All the clamps are rusty busty though.

Its not loud, just has a nice rumble to it. A must do mod.
 
Would have to trace water flow through whole system to determine if it would really be an impact. Anyone have a pircture of the water flow? I think it actually travels through the heads in parallel not in series. So more flow on the end going towards radiator is a good thing.
 
I just chipped the burb and now have 14lbs. and the egts shoot up to 1300 at half throttle or more. How much will the exh help

Maybe your gauge needs to be calibrated.

If you check the xover temp at warmed up idle with an infared thermometer and check it against the gauge maybe you will see it is XX% off. So if at idle your IR sensor says exhaust pipe is 200 but gauge shows 260, then when it reads 1300F it may actually only be 1000F

While cruising it should only be about 300F

Either that or if the temps are accurate, my thought would be injectors are dribbling instead of spraying. Probably a concern either way.
 
Even though its your thread, you should start a new one for the high egt issue.

If guage is accurate, How much boost are you drawing at 1/2 throttle to get such high EGT's?

Did you put in a good known vendors chip? Some chips were known to do harm, but This was years ago.

That just sounds way too high to even be possible at 1/2 throttle. Does sound like gauge error, unless your just overboosting and your GM-X turbo is cranking up the heat.

Sealed airbox helps if yours is open, Good filter of course.
TM lowered my EGT's, as did the exhaust, but you have new D/P and no kitty...

Modifiying the thermocouple may throw off readings (shortening/lenghtening)??

Poor cooling system? E-Brake hung dragging?
 
That factory filter does suck. There is a tube inside the fender in 94s that should be taken out too, because it restricts air more than helps direct it.

Those EGTs are pretty crazy unreal, unless you were a mile into an 8% grade with an 8000lb sail on your back.
 
maybe try backing down your TM a little bit, once you hit the point of diminishing returns on the ol GM-x turbo you will get into a tailspin of heat, Takes more work to get more boost, intake air becomes piping hot from poor GM-4 efficiencies, causing even more engine stress to create even more boost, creating more heat...etc.

When I'm climbing steep grades highway when I'm at 9 psi boost I'm around 900 EGT's doing 65. But I feel like I'm barely hitting the APP. If my TM was set to create 12psi of sustained boost I'm sure my EGT's would be higher too.

Main problem here is 1200+ sustained is considered dangerous for engine health. Add a trailer to this and its not looking good.
 
I run my GM4 to 20+psi, and at 90mph up mile long 7% grades it will sit at about 15psi my EGTs are less than 900F preturbo. Thats nothing but diesel fuel, not propane or WMI. It did improve with the 4" to 5" exhaust and aeroturbine mufflers.

The only time I have ever seen EGTs over 1000F was when my vacuum tube cracked and I lost turbo, and when ATT was on with a catalytic converter and wouldnt make more than 5psi boost.

I also measure backpressure and it only starts getting really bad over about 15psi. It does start climbing faster once you get over 10psi boost though.
 
Real life data trumps my theories...

Focus on the air coming in. Get the snorkel out, a new good filter setup (k47 is preferable).

Here may be a case that is the opposite of the ATT to GM8 Effect. The engine may have to work twice as to create the same 12psi of boost as a system with a free flowing intake path.

I would think the exhaust path is free flowing enough, perhaps the 2.75 restriction (stock exhaust) is hindering high boost performance, combined with poor intake flow.
 
BUT, if in fact your injectors are 'peeing' (Thanks Missy) into the cylinders instead of misting, you may find this out by melting your pistons if you tow in these conditions, especially already being so hot.
 
My results may not be typical, but I'm saying the Gm4 can do OK, and EGTs shouldnt be jumping to 1000F quickly, especially when not towing. Its not that bad of a turbo. I used to have 3" exhaust with catalytic converter and big muffler and my EGTs still wouldnt climb that fast and that high even on steep grades.

Turbo whine went way up on mine when I switched to the underhood cone filter, especially considering I didnt hear it at all with stock air filter. That could be part of the problem, since I ripped that out pretty soon after getting the truck. I do get some high IATs, but so far that hasnt translated into high EGTs or high ECTs.

I think the stock 97+ cone filters have twice the surface area as these rectangles.
 
My results may not be typical, but I'm saying the Gm4 can do OK, and EGTs shouldnt be jumping to 1000F quickly, especially when not towing. Its not that bad of a turbo. I used to have 3" exhaust with catalytic converter and big muffler and my EGTs still wouldnt climb that fast and that high even on steep grades.

Turbo whine went way up on mine when I switched to the underhood cone filter, especially considering I didnt hear it at all with stock air filter. That could be part of the problem, since I ripped that out pretty soon after getting the truck. I do get some high IATs, but so far that hasnt translated into high EGTs or high ECTs.

I think the stock 97+ cone filters have twice the surface area as these rectangles.

Just to avoid confusion the 97+ k47 airbox's have Cylindrical Filters stock, not cone shaped.
 
That is a better description of the filter, A cylinder is a cone, but better just described as a cylinder. Do you get them with an inverted cone on the tip, or just flat tipped?
 
That is a better description of the filter, A cylinder is a cone, but better just described as a cylinder. Do you get them with an inverted cone on the tip, or just flat tipped?

Both my K&N and AmSoil NanoFibers have flat tipped AFAIK.
 
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