TREX-GTP combo coming soon
Thread Starter
Joined: Nov 2001
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From: Cecil County Raceway!!!
TREX-GTP combo coming soon Been keeping it under wraps for a while but I now have almost all the parts I need and I now have a new concrete garage floor in my 'shop'
After I give the concrete 2 weeks to harden (next Friday), I'm putting the car in the garage, pulling the engine and getting to work.
Gonna flycut the crap out of the pistons to get the required clearance (I have .040 milled off my 5.3L heads)
Stuff in a TREX (mine spec'ed to 242.2/248.1 .607/.612 109.7) and degree it in (no dot-to-dot this time around
)
Change out the 918s for Crane duals shimmed to 1.770" installed height
Replace the main/rod bearings (and actually set the clearances this time)
Going to tune the car open loop (disable the O2 sensors) since I know own my own Wideband setup
Hoping for a reasonable improvement...going from XE lobes (232/232 112LSA)
I think the GTP S2 heads, big cam and 90mm intake setup will make for a scary combo
After I give the concrete 2 weeks to harden (next Friday), I'm putting the car in the garage, pulling the engine and getting to work.
Gonna flycut the crap out of the pistons to get the required clearance (I have .040 milled off my 5.3L heads)
Stuff in a TREX (mine spec'ed to 242.2/248.1 .607/.612 109.7) and degree it in (no dot-to-dot this time around
)Change out the 918s for Crane duals shimmed to 1.770" installed height
Replace the main/rod bearings (and actually set the clearances this time)
Going to tune the car open loop (disable the O2 sensors) since I know own my own Wideband setup
Hoping for a reasonable improvement...going from XE lobes (232/232 112LSA)
I think the GTP S2 heads, big cam and 90mm intake setup will make for a scary combo
Damn sounds sweet I have my TREX on the way I may need some tuning assistance from you if you are willing I am in Westminster but I will drive for help!!
I was wondering when someone would pair the TREX up with a solid intake and a great flowing head
I was wondering when someone would pair the TREX up with a solid intake and a great flowing head
Thread Starter
Joined: Nov 2001
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From: Cecil County Raceway!!!
Originally Posted by 1QWIKZ
i am pondering the same combo, but my GTPs were milled .055 and have 2.05/1.60 valves.
Not sure if I'd go much further than .100 which you might have to do
TECH Senior Member
Joined: Nov 2001
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You know Brian you should consider buying a set of diamond pistons/eagle rods and having it all balanced while you have it apart. Then you could throw some spray and REVS at it safely
Looking forward to hearing the results
Looking forward to hearing the results
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I agree with Chris. If you're pulling everything apart, don't bother cutting the **** out of stock pistons. Put a set of goodies in there, so the insurance is there and the future possibility of Nitrous is available 
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Verdad Gallardo Thread Starter
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From: Cecil County Raceway!!!
I don't have the extra $2K+ to throw at it now...
pistons + rings + balancing + rods (why put in good pistons but leave factory rods
)
flycutting is cheap and my rings are good right now
pistons + rings + balancing + rods (why put in good pistons but leave factory rods
)flycutting is cheap and my rings are good right now
TECH Enthusiast
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From: SC
sounds kick a**, although I kinda agree with at least seeing if you can get domed in pistons rather than flycut the crap out the stockers. A new set of diamonds around $600 if I remember right.
Good luck, keep us posted!
Good luck, keep us posted!
Thread Starter
Joined: Nov 2001
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From: Cecil County Raceway!!!
Originally Posted by ezss
sounds kick a**, although I kinda agree with at least seeing if you can get domed in pistons rather than flycut the crap out the stockers. A new set of diamonds around $600 if I remember right.
Good luck, keep us posted!
Good luck, keep us posted!
I'm not 100% sure how much will need to be cut. I plotted valve events for the 2 cams and it looks like the intake will be nearly the same but exhaust will get significantly tighter (due to the decreased LSA)
I already have .050 cut off the intakes. Nothing on the exhaust...yet
I'm in construction as an engineer....we normally see 7 day breaks on concrete being greater than the design criteria....3,000 psi normally breaks around 3,400 psi after 7 days, so if you wanted you could get to work a little earlier rather than making us all wait for two weeks
Get it damp with a garden hose and cover it with plastic....it will cure even quicker and a LOT harder.
Get it damp with a garden hose and cover it with plastic....it will cure even quicker and a LOT harder.
Originally Posted by Fireball
You may be getting real close for comfort. I'm probably gonna have to cut .080-.090 off of my pistons for clearance...
Not sure if I'd go much further than .100 which you might have to do
Not sure if I'd go much further than .100 which you might have to do
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From: SC
Originally Posted by Fireball
but you have to hone and replace rings too then rebalance...more than I care to dump in it right now
Oh yeah...i forgot about that part. Guess thats why im not building my own engine (aside from lack of mechanical ability and only 13 seconds of patience for any given situation). Might as well save all that for the next engine
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From: Cecil County Raceway!!!
Almost done...
New bearings are in and clearanced, Cam is in and degreed...
Still need to do the flycuts (I checked and its EXTREMELY tight in there )
Still waiting on the springs and retainers from thunder which should ship this week from what I've read...
Maybe...just maybe...I'll have it running by Sunday
New bearings are in and clearanced, Cam is in and degreed...
Still need to do the flycuts (I checked and its EXTREMELY tight in there
)Still waiting on the springs and retainers from thunder which should ship this week from what I've read...
Maybe...just maybe...I'll have it running by Sunday
I wanted to put the Trex in 9 months ago with my GTP heads and Jeff was scared to tune it 
I tried to tell him an A4 with a 5,000 stall and 4.10's would be money
But he talked me out of it
Good luck with it, I'm sure I'll seee it at the next EFA event
I tried to tell him an A4 with a 5,000 stall and 4.10's would be money
But he talked me out of it
Good luck with it, I'm sure I'll seee it at the next EFA event
Thread Starter
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From: Cecil County Raceway!!!
of course I ran into some snags
found a bent exhaust valve (#3 kissed the piston...it appeared to have floated
)
so I had to get a new valve from GTP...will have it Thursday. Also set up my springs to 1.750 and now thunder recommended to set them up at 1.720 based on the recent change in material in the Crane duals...so I had to buy new valve seals
motor is back in the car (with .090 cut off the intakes and .070 cut off the exhausts
)...just waiting on head installation then it'll be running again
found a bent exhaust valve (#3 kissed the piston...it appeared to have floated
)so I had to get a new valve from GTP...will have it Thursday. Also set up my springs to 1.750 and now thunder recommended to set them up at 1.720 based on the recent change in material in the Crane duals...so I had to buy new valve seals
motor is back in the car (with .090 cut off the intakes and .070 cut off the exhausts
)...just waiting on head installation then it'll be running again 