MTL_Z28

I was just wanting to hear people's thoughts on my next motor build. Mostly I need opinions on what to do about engine management, ignition and fuel system. Also the lubrication of the motor and turbo.

Here is a rundown of the shortblock:
4340 Forged Scat crank
4340 Forged Eagle H-beams with ARP L-19 rod bolts
JE Extreme duty 23 degree inverted dome pistons, total seal rings
4-bolt splayed main caps, ARP 2000 studs
Block has been half filled with hardblock

The heads are LT1 castings CNC ported by ET Performance
assembled with PAC beehive springs
2.02 int./1.60 exh. valves
Combustion chamber volume is 58cc

I also have a BRE custom turbo cam... 22X/23X duration, gross lift .56X/.56X and 114 lobe sep. angle.

After speaking with Jon at LT1boost, we decided that I should go with a PT-88 header kit with 4" air-to-air intercooler and alky meth injection kit. My hp objectives are in the 800-900 "ish" range with the T56. Eventually though when the car is tuned properly and running right I will probably switch to a TH400 or 4L80E imo for more consistant drag race performance. I already have a moser 12-bolt rear with 4.10's installed in the car.


So as you can see I am going to need alot of help LOL!!
Here's a list of questions I thought of so far:

1)For starters, what head gasket should I run?? I calculated my CR and with a .040 compressed thickness I get 8.8-to-1, but if I use .020 thickness then I end up with 9.2-to-1. the guy who sold me my motor said to use the MLS Cometic .040 thickness. Should I use this gasket? I know lower compression is better for boost so maybe I should use the thicker gaskets?

2)What intake manifold should I run? I have heard stock is fine even for big HP motors... I was going to buy a 58mm TB or monoblade and have the TB ports on the stock intake opened. Should this be ok?

3)As for engine management, everyone I have spoken to has recommended doing away with the stock PCM and going with a aftermarket ECU like the FAST Xfi, is this the best option? What will I need to run this aftermarket computer? I have browsed the website and it looks pretty complicated. One of my friends has recommended ditching the factory PCM and optispark setup and going with the FAST Xfi and a MSD crank trigger and converting to coil-per-cylinder ignition. That sounds like a good idea but very complicated?? Are there other options for igntion systems in applications like this?

4)What type of fuel system am I going to need to run? I currently just have a Wlabro 255 GPH pump in the stock tank I imagine it's not going to cut it LMAO. What about fuel lines/rails/injectors??

5)As for lubrication, the person who sold me this motor also sold me a really nice oil pan... it's a 8qt Drag pan from Billet fabrication. He also had a Melling M select performance HV/SP oil pump #10555c. After doing some research it seems like this is a good pump for a high capacity aftermarket pan like this one. It also looks like it would be best to buy a bolt on pickup for this specific pump. And also from searching it looks like it's a good idea to keep the stock windage tray in place? Anything else I need to consider for lubrication? What oil and filter should I run on this motor? Also as far as the oiling system for the turbo, what else will need to be done?


I will probably have a ton more questions to ask but that's it for now As always I appreciate the help guys.

97WS6SCharged

Are you using bolts or studs? I'd run the Cometics with studs personally. I run arp bolts on my supercharged car with good old felpro gaskets and haven't had any issues.

Depends on your budget. The stock intake works though.

Is the car going to be just a drag racer or what? Aftermarket ECUs are nice but they lack many of the features that stock PCMs have. They also generally require quite a bit more time tuning since they are essentially a blank slate unlike the stock PCMs. You may look into the 24x conversion from EFI Connection. It allows you to run a late model LS1 PCM which you can load with 2 bar map tunes and other niceties.

You can probably run a 2nd pump and be ok, people have made the power you're talking about with two 255s in the tank. You can also have the stock rails modified for AN fittings to run them in parallel, they're already big enough inside to support the power. You'll also need a different regulator. I run a -8 feed on my car from the tank to the rails and a -6 return. You'll need to size your injectors to match your goals.

I won't comment on the pan without seeing it. It's usually a better idea to brazen weld the pickup onto the pump so it doesn't fall off. The oil you run should be determined by the clearances in the motor. I like Mobil filters personally but as long as you use a good quality one you should be fine. You probably need to tap the pan for the oil return from the turbo if you haven't done so already.

Purple Poncho

Hi Fab,

It sounds like it will be a monster. These are all IMO of course.

You will also need a real good clutch and gauges, boost fuel pressure and a wideband.

Can't wait to see it!

MTL_Z28

Yes I have a ARP head stud & bolt kit I will be using.


True I did some searching and it seems like a few ppl are running big FI applications with stock LT1 intake and stock throttle body even. I guess since the air is being forced into the intake these components aren't as important as in a N/A build...


I would say mostly a summer car for weekends with moderate track use. I don't think it will be an all out race car, though I would like to push it hard at the track and on the dyno. I checked out the EFI Connection website it looks interesting... It is basically what I would like to do though. To run the the cam and crank sensors though it says I need a single roller timing chain? I bought a Cloyes billet double roller (p/n 3545X9) it's a nice piece but if it will not work then I will sell it and buy a single roller chain. Can you recommend a nice strong one that will work?

But I like this option. It's also not that expensive, it looks like for about 2200$ I can have everything I need, the cam/crank sensors, LS1 PCM, engine harness, and even the LS2 coils with connectors and mounting brackets. Does not include the software though it looks like.


Thanks for the info. I'm guessing I'm going to need a AFPR? Do you have a brand or p/n sugestion? Any one will do?

MTL_Z28

Here's the pan













Ok so good idea I'll try to reach the engine builder to get specs or at least ask them what motor oil they would recommend running in this application.


Also I have seen some people with turbo setups use scavenge pumps? This is to help circulate the oil to/from the turbo iirc. Will I need one or it depends on the placement of the turbo? I guess I'll speak to Jon about that...

MTL_Z28

Hey Mat what's up


Yeah the other gasket option is the Fel-Pro 1074 that everyone seems to have good results with... I guess I'll have to decide between this and the Cometics.

Yeah I was looking at the website again it looks nicely organized and you're right from a hardware point of view it does seem cost effective, but then it looks like I have to purchase the tuning software like EFI Live or HP Tuners which are quite expensive, and also the wideband... The thing about FAST XFI, all this stuff is included in the system. But nonetheless it is an interesting option.

Alright so I already have a pretty good complete shopping list for the fuel system it looks like




Yeah I will be sure to order some more autometer gauges... I'm thinking oil psi (mechanical.. have one already), Fuel psi, A/F ratio, Vac./Boost will be good.
For the clutch, I have a SPEC stage 3 right now that will stay in... It should be ok just to get the project running... Like I said earlier (I know you will think this is super gay though) I will probably be switching to auto trans eventually when the project is really up and running. Maybe you can convince me to keep the 6-speed? LOL it will probably take a while for everything to come together though. At least I still have my stock motor to play with in the meantime...

I heard you were working on a little something yourself

97WS6SCharged

That's a nice pan. You may be able to use that port above the oil level sensor but I'm not 100% certain. Mine is tapped near the front driver side.

Hope you got the hex keyed head studs, they're definitely worth the extra cash if you're running studs.

It's not that they're really any less important; it's just that the LT1 intake has short runners which work well for a performance application. There are other options; just depends on how much cash you want to spend. Then again, people have made over 1k rwhp with the factory intake.

That's what's kept me from doing the conversion mostly. Stupid CPS. I know the LS1 guys run single roller chains all the time without issue but I've had my double roller in the car for a while now.

Correct, you still have to supply your own copy of HP Tuners, EFI Live, etc... Also, if you can supply your own coils and PCM (junk yard, boards, local sales, etc...) you can save quite a bit of cash. If you can repin your own harness then you can save even more.

I run an Aeromotive A1000 on mine.




Just some other thoughts: Size the injectors to the combination. 96#s may work or they may be too big or too small for your goals (not being negative to Poncho, just sayin). Also I would use an electrical oil pressure gauge if you feel the need to use one at all. Running an oil hose into these cars wouldn't be much fun plus they can leak.

RealQuick

This will be a badass build.

97WS6SCharged

You doing the work?

MTL_Z28

Just the turbo kit

RealQuick

I will need the pan for mockup when it is time to build the kit.

MTL_Z28

Shouldn't be a problem

RealQuick

When do you want me to get going on the kit?

MTL_Z28

Pretty soon actually. I just have to make a last order from summit racing on some parts to finish the final motor assembly and the next step after that is the turbo kit...

RealQuick

That sounds good. I am moving the shop next month, so I won't be able to start till August.