I'm in need of some guidance. Recently got our TPI setup on a 327 running with a small T3 turbo from a 6BT Cummins. Shockingly it runs out of air, HP and torque prior to 3800, according to the dyno results. I'm looking for a guideline for a turbo for a low boost setup (10-15psi) in a car that will be daily driven for the 98% of it's life that hopefully can make 500 ft/lb mat the wheels when cranked up.

The engine has a stock TPI, Profiler 185 heads, 80 lb injectors, MS2 controller, forged pistons, 10:1 SCR & 8.3 DCR, XS power single turbo manifold, about 4 ft of exhaust behind the turbo, 220ish dgree FT cam, 28x14 intercooler.

I was thinking an ebay 70mm or 76mm. The AR's I'm not sure of and I'm not sure that either a 70 or 76mm is alright.

Any help/advice is greatly appreciated - thanks - Jim

 

ebay gt45

 

http://www.ebay.com/itm/GT45-T4-V-BAND-1-15-A-R-92MM-HUGE-1000-HPS-BOOST-UPGRADE-RACING-TURBOCHARGER-GT-/150581666321?hash=item230f5de211&vxp=mtrbe aware u need to get the downpipe adapter/vband off ebay as well

http://www.ebay.com/itm/GT45-ZINC-COATED-3-25-TURBO-TURBOCHARGER-DOWNPIPE-EXHAUST-V-BAND-CLAMPS-FLANGE-/111614884429?hash=item19fcc3fa4d&vxp=mtr

 

or a single one of these will work and be better for the street
http://www.ebay.com/itm/T76-T4-turb-81-A-R-Comp-80-A-R-oil-cold-1000-HP-Turbo-TurboCharger-14US-/301425651776?hash=item462e5e7040&vxp=mtr
i run twins onf those on my car

 

So I guess you don't think the 76 mm with .96 - 1.-- turbine a/r is to big? Where would you think the 76 mm will spool?

 

the gt45 with its 1.05 ar spools around 3k on a stock 350
the 76 with the 9x housing and ptrim wheel should spool a bunch faster then that on the 350

with a 327 id expect around 2500 ish out of the 76 maybe even sooner depending on what the hotside looks like

 

i would think you would want something down in the 60's. pt6266 maybe?

 

Thanks. That was the info I was looking for. Beginning to spool around 2500 is what I'm after .

 

if he was buying a brand name tuurbo if go for something in the 64-66mm range being the china turbos arent as efficiant i think the 76 will work out great for him

the ideal turbo would be the gt45 cold side 70/104mm wheel coupled with the t76's p-trim turbine, unfortunalty there are no ebay turbos fitting that sizing that i would currently trust

there is a t72 with a 72mm compressor and a ptrim turbine but i only know one person so far whos run it so i cant recommend it specially not ever having run one myself

 

Jim, my old T72 with .96 a/r started spooling around 2500-RPM, and this was on a 305 TPI. If your running a 327 w/TPI, then I would consider a T76 with the same .96 a/r. The short video below is with the old T72 and stock converter (stock converter couples at 1500-RPM, so lag was definitely an issue), started spooling at 2500-RPM though right after and mph shot up very fast, but I had to let go because of the kids and the 25 mph speed limit...

 

Thanks to both of you guys and you've made up my mind. We'll most likely go with one of these :

http://www.on3performance.com/shop/o...-turbocharger/

The local tuner has several of these running locally and has had no issues and one of my son's friends is running an 88mm On3 making darn near 1000 rwhp on a 6.0 with no issues.

I'll let you know how it turns out and I really appreciate the advice.

jim

 

I have question that I hope someone can answer quickly. I'm presently running my BOV line tee'd off from the PCV line and it's a PITA because I can't remove the valve cover with it on and it looks like A**. Here's the question finally, is the port on the bottom of the stock TPI TB a full manifold port or ported vacuum source?

That port was originally for the vacuum cannister (TB is from an '85 Vette) and I've been searching for over an hour to find the answer ti this question with no success.

As always, help is aprreciated!

 

Jim, start the engine, pull the vacuum line that you are inquiring about, and feel the port on the throttle body with your finger. If there is no suction, then it isn't a full vacuum source. Keep your finger there, then raise the throttle with your other hand, if you begin to feel suction, then you know it is timed.

 

Well, the reason for the question is that we are in the process of putting on the 76mm turbo and it isn't running presently. We got boned by the turbo drain as our old one that takes a #10 JIC fitting and won't fit the new one. So we are waiting for a new drain with a push on style fitting. Hence the reason for my question. And since we are waiting I thought this would be a great time to drop the spark plug gap to .030, install a new set of wires and adjust the valves. We still have to refab the down pipe, but fortunately the entire exhaust system is about 4 1/2' long - so that shouldn't be much of a job.

I'm trying to get every little thing done that ought to be since we are waiting.

 

Two large ports on the passenger side of the throttle body, one leading from the valve cover to the throttle body is full vacuum, the other line leading from the charcoal canister to the throttle body isn't.

 

Thanks, even though that is unfortunate for me. I'm thinking I'll pull off the plenum and drill and tap a port in it for the BOV to take care of it then.

Thanks for the help - Jim

 

Did end up drilling and tapping a port in the plenum. Seems to work fine. The 76mm is FINALLY installed and ready for some driving. I will let you know how it works out. Hopefully we can make 500 rw ft/lbs on the dyno.

 

That came out very nice! My eyes are playing tricks on me, and I am too lazy to check to see if it was already mentioned, but is that an '80 Malibu...?

Edit: Nope, an '80 Cutlass, perhaps lol...

 

Yay congrats on completing the build! Cant wait to see results finally! I want to turbo my 305 still and wanted to see some others results

 

80 Cutlass, not Malibu.

 

We got it running and base tuned but are yet to hit the dyno or strip. FWIW, my son mentioned yesterday that he doesn't want to take it bracket racing due to the rear (10 bolt 7.5) until we find an 8.5 10 bolt or 9". He wants to drive it for the summer without attempting to break it, which is fine by me.

Hopefully to the dyno soon, though. How does it run, if you wonder? It will break the rear end free at less than 70% percent throttle when it hits 3rd gear - HOLD THE H#@! ON AND BE READY TO DRIVE!!!! I've never driven anything like it. It is the best cruising power I've ever had. If driving between 65-70 around 10-12% TPS and pick the throttle upto 25-30% or so it'll pickup to 80 in about 2 seconds - with no motor effort or struggle. If doing the same and knock out of OD and put it to 50%ish TPS it'll be be to 85 in what seems like a second with, again, no effort or struggle on the motor - it is truly unbelievable.

I have 2 questions about the fuel system though. After doing as much research and question asking as I can, I'm yet to come up with answers. Our system is an inline 255LPH Walbro through a stock 85 Vette filter and line size (8mm) with the stock return size (6mm I believe). And presently running 43 psi of FP and boost referenced 1:1 so at 8psi the FP is at 53 (give or take a lb according to my gauge) with a Southbay adjustable regulator.
1st question, I'm considering dropping the base FP to 35-37 with the idea that lower pressure will allow for more flow - is that correct/workable and worth it?
2nd question, I'm considering running a second pump to the driver side rail via drilling and tapping the rail for a 5/16 or 8mm line - will the 6mm return handle both the return between the rails and from the regulator to the tank with two pumps?

If you think our fuel system will handle 550-600 crank HP, then let me know, but I think it isn't up to the task.

Thanks for all of the help so far - Jim

 

Lower pressure will help get some volume out of it but 600 crank in boost will be pushing the limit on that pump. Be careful with it and monitor fuel pressure.

Twin pumps would be ideal and return line should handle it. Or upgrade to a larger inline like a bosch 044

 

Interesting, my first car was a 78 cutlass and I still have it. Nice job on the car so far!

 

Here's my plan, after what I've read and been told, two of the Walbro's 'Y'd on the engine side of primary filter and run another secondary filter with a set of stock fuel lines to driver side rail. What I was looking for was if the stock return line size would handle it.

Thanks a bunch - Jim

 

nice job man

 

I'm running the 400lph walbro. (the fat boy).

http://www.full-race.com/store/fuel-...ro-400lph.html



-- Joe

 

I don't think that pump can be bought as an inline. I much prefer to run the inline rather then an in tank. For the only reason that it's an easier setup to install, check and service if needed.

We have been going back and forth as to which would the most basic system - changing to a Bosch 044 and changing to larger fuel lines or adding another 255 and adding a new line to the other rail (and taking a chance that the fuel return line is too small when both pumps are running and the FP is elevated.) Not trying to sound pessimistic, but I'll probably discover how to do it right after doing it the 1st time - lol.

I'm also considering just running the second pump on a switch that can e turned on when at the track or dyno because this thing will never need the second pump on the street. That would also give me a backup in case the primary pump poops out :/.

 

So we made it to the dyno and ran it out of fuel at 14 psi - shocking. It made 350/410 to the wheels, but had more in it (not a ton, but some.)

We've already ordered the second pump, filters and fittings. If I don't run both pumps at the same time, then will I need a check valve between the engine and either the secondary filter or pump?

Also, we had to put the timing in the tank. I'm guessing that some of it is due to compression (9.9:1). We backed it down to 15-16 degrees at full boost. So we are on the plan to run E85. I was told by many that the timing would need to drop a degree per psi to be safe, but we were more like 1.5 degrees per psi - any thoughts?

 

All depends on the setup. Some need more than 1 deg per lb.

Also what did you use for fuel pump? If bosche 44 you will need a check valve. If a walbro 255 it should already have a built in check valve

 

Walbro 255.

 

We have gathered parts and are in the process of putting it together. Picked up an 8.5" rear with a Yukon Duragrip and a set of Moser 30 spline axles; the second fuel pump, filters and fittings; exhaust to rebuild the crossover and right side header, and a roller. Hopefully we can get it all together before winter's done and maybe hit the dyno before driving season.

Wanted to say thanks to all for not giving me crap over posting even though I'm only running a thirdgen intake system. You guys have been a plethura of info.