Monty

I'll find out today. You're right, this thing is heavy, but from what I hear they are practically bullet proof, especially in a light car. Art Carr said it's rated for 1500 lb ft and a 24,000lb GVW vehicle, luckily our cars are a little lighter than that ;).

I also got my new turbo pistons in too. Had to go with a full dish to get the CR down to 8.5.

Golden80

Please please please take lots of pics! I'm hoping to put one in my car in the future and would like to see what's involved.

Thanks,
Matt

gkull

Art Carr????? They ask me last fall if I could get some action photos drag racing so they could put them in their catalog. I might just do it if I get a 4L80E out of the deal in trade for this 700 I got from them.

I hope that it works out. I ask an engineer once, "Do you get more force if you use a concave piston." I only wondered about this because you actually have more square inches of surface area.

What's it going to do to the quench? :confused:

If you'ld like give me a call later when your done working on it.


[Modified by gkull, 10:12 AM 1/5/2002]

gkull

Oh! I see, after a closer look you don't have an Art Carr Tranny. Mr good wrench ;)

Monty

No, the convertor is Art Carr, the tranny is a remanufactured Goodwrench. But when I was talking to Art Carr about the convertor, they gave me those specs, and said that for a street car without slicks, that it would hold up fine. Stock, they are rated for 800 ft lbs or so.

Obviously, the quench area is smaller since the dish had to be so large to reduce the CR. Basically the only quench will be the raised part around the circumference. Supposedly the effect is that rather than the quench being a wedge shape, it's partially circular and moved the charge more towards the center of the chamber rather than to one end. This is how turbo pistons are made though, the turbo Buick pistons are very similar on design. I was concerned about the quench area myslef, but according to Fast Times, JE, and Precision, it isn't as big of an issue in a forced induction application like it is in anaturally aspirated application. I looked at some other pistons they were using on their 2000hp NMCA/NSCA turbo motors and they are the same. All this turbo stuff is a little different than what I'm used to.

We're also going to run a stainless steel, moly faced top ring, Inconel exhaust valves, and I 'm really considering the Swain coatings on the piston tops, combustion chamber and valves, and maybe even the exhaust runners.

45ACP

As I recall the stock 4L80E converter weighs in at 60lbs. Mount a few of those in a row on a lathe and you really know it!

Did you get the double stator unit?

This is the first 4L80E ever fitted into a C3 that I know of. It will make for interesting reading. If you have had any trouble breaking trannies . . . I think your troubles are about to be over.

e3pres

No. It will not fit. You should send it immediatly to:
J. Adam Thomas
748 W. 7th St...

Just kidding. :lol: I do want lots of pics though.

Good luck.

gkull

Swains piston coatings are not all that far from Red73's house. I paided $225 including shipping to have my JE's done. If I had to do it over again I would have done the ports also. What is the static C/R with those pistons.

45ACP - 60#'s damn that's allot. Stock 700 11 or 12 inchers are to big for me. 8 to 9.5 inch is all you really need in a street car. ;)


[Modified by gkull, 12:00 PM 1/5/2002]

Stingy74

What kind of warranty does goodwrench offer you for the transmission? I think it will outlast the car seeing as your not going to have slicks. Have fun! :)

Golden80

On another note...

You bought it...and then decided to ask if it would fit? :crazy:

:lol: Matt

Monty

I had to cut off a small 'ear' at the front of the transmission, but other than that, it fits like a glove. I'm going to have to reposition my starter cable but that's it. The transmission crossmember is going to have to be modified, as the 4L80E's mounting points are about 1" farther back than the 700R4's that my original factory crossmember was made for. Also, the driveshaft will have to be shortened, I'm guessing about 4", but don't know for sure yet since I haven't received the Turbo 400 yoke yet, a got a billet 4340 yoke from Strange.

Now it's a matter of getting the transmission computer from TCI/FAST and reinstalling my factory shifter.

Gkull, those pistons will give me slightly less than 8.5CR with my heads and a standard gasket.

45ACP, I don't have the the convertor yet. I order 9" 3500 stall Art Carr ealier this week, along with a billet Reactor products flexplate.

Stingy74, GM offers a 36,000 mile warranty, but I doubt they would honor it if I broke it. If it breaks, I'll just rebuild it will all the race stuff. These trannys are supposed to be tough, one of the strongest ever put in a non-commercial vehicle.





[Modified by Monty, 12:36 PM 1/5/2002]

Monty

Golden80,

It was a joke between Gkull and I, going back to a previous conversation.

gkull

Great news! Is that in your garage? Because it looks like your sand blaster in the background.

I wish my tranny came with a box to adjust shift points. :(

Merlin522

Good deal, Monty. I'm not sure why people are so freaked out about it fitting. It's just a Turbo400 with another gear. Although I really love shifting, I fear I will be following in your path soon. Without slicks, that thing will live far in excess of 1,000 HP. It's the most stud tranny you can by that is still "streetable". Yes, you can buy a Lenco - they even make a 5 speed, but shifting it would be a nightmare & you have to rip out your entire console. You have chosen wisely!! For Merlin II I'm definitely using the 4L80E as well...

Merlin522

P.S. You may want to design the heads to drop that CR even further. The lower, the better. I think we ended up with 7.8 You will more than make up for any power loss with the extra boost & the engine will live longer...

Monty

George, as we discussed before, chevy may have changed the transmission tunnel shape, but if they didn't it certainly does fit.

Steve, It was just a little uncertainty. I don't know of anyone else that has put a 4L80E in a C3 before. I was pretty certain it would fit, being beasically a modified TH400 as you mentioned, but it is a little longer, and the back half of it is much wider. The closest area of potential interference is actually the tail housing becuase it really doesn't taper down that much, and the tranny tunnel get pretty narrow in that area.

I really wanted to keep the TKO in there, but turbo's just work so much better with auto's and I was afraid the TKO become the weak link. Now it should just be the rear end.

We may open the heads up a couple of cc's, but I don't want to if I don't have to. Since quench is no longer an issue, I may also run a thicker .050" gasket. We'll see, we really have to see how it all fits together and do all the math first. I don't really want to go below 8.0.

Merlin522

Why are you opposed to going below 8? You can get more power by going lower. Just curious...

Monty

1200-1300hp is enough for me - I don't race regularly, and I'll never see any salt flats. If I can make the power with 20psi of boost, and it runs detonation free with 8.5CR, then that's fine. I just don't want to go any lower than I have to so that the engine is still relatively efficient, and has good throttle response and off-idle torque before the turbo's start making boost. I am told that it should start making full boost in the 3000-3500 rpm range - this is based off of what John Meaney's car does - so it shouldn't be a significant issue. I just acknowledge that the majority of the time, I'm going to be stuck in traffic, or in 35mph areas where the engine is only turning 2000-2500 rpm. It may come as a shock, but a guess it's just a little more practical.

Merlin522

Some good points. It's all basically moot at the power levels we are at. Turbo's may be different than superchargers, so I'll leave it at that. You have some great shops you are working with, so they'll know what to do. I just know that in general, the lower you get the engine compression, the less chance you will have of detonation. The intercooler is critical - which you have, so everything should be fine. These new turbos spool so fast I don't think you are going to see any lag whatsoever. Technology really has come a long way. I'm eagerly watching your progress since I will be going down the same path with my next car. I may only use one big turbo though. What's your thoughts on that issue?

Monty

You gotta set your target somewhere. Mine is to replicate John Meaney's performance. Luckily, the owner of Fast Times is freinds with him, and Precision was willing to discuss his combination with me, and set me up with the same turbo's, just with newer, more efficient turbine housings. Based on the targeted goal, I don't need to go below 8.0 and I won't need to run more than 20 lbs of boost or so.

We ordered the largest intercooler core that Spearco/Turbonetics makes - 20" x 16" x 3.5", rated at 1500 cfm @ 1.5 psi pressure drop. Of course, you can run more cfm through it, but the pressure loss would increase.

There are pro's and con's of going either way - single or twin - as with most everything else. Alot of people think that two smaller turbo's won't have as much lag as a single larger turbo. That is not necessarily true. With two turbo's you're dividing the exhaust volume and energy in half, whereas the single is getting it all. That's what drives the turbo. Heat can be an issue as well. With the two turbo's you're dividing and spreading the heat around, whereas the single concentrates it all in one area. Those suckers can get hot.

Probably the biggest consideration is packaging and cost. The cost really isn't much of an issue, because twon smaller turbo's cost about as much as a single larger, relatively speaking, but running 2 wastegates, 2 blow off valves, plus twice the plumbing can add up. Probably the most important is packaging it all in. The singel turbo setup does have the benefit of less plumning, other than the crossover to mate the two cylinder banks. This is also a little less efficient since you're going to lose some exhaust heat and energy with all that pre-turbo plumbing.

But as you said earlier, the tubo technology has really come a long way, with many more turbochargers options, designs, and hybrids. It's really a shame that so many people have formed their opinions of turbo cars based on OEM applications.