.63 to .82 exhaust housing - Slower!

[Doug71zt]

I had a chance to compare the performance of my car at the strip with .63 stage 3 and .82 stage 3 exhaust housings. Now here is the important part - With 225/45/17 street tires.

With the .63 housing, the car will launch at 3.5-4K and not bog - boost comes up quick and it will go 2.1 60's.

With the .82 housing - it will bog and take a little while to recover. 2.4-2.6 60' times. BadBadBad.

It is making more HP at the top end - because the ET only drops .2 (IE - 12.6-12.7 to 12.8-12.9).

 

With the .82 housing - if I try to launch on boost, it will BLOW the tires away. If I short-shift to 2nd, it will blow them away again and get all squirrelly.

 

Now if I run the slicks, this will all change because it will go 1.7-1.8 on slicks all day. And launching on the boost won't be a problem.

 

But - I got tossed off the track for no DS hoop, so no slicks until I get a hoop....

 

As for trap speed, with 13 psi on 91 pump gas, it will now go 115-116. Before with the .63 housing, I had to run 15-16 psi on 94 pump gas to get 116. It will go faster with better fuel, as I had to pull some timing to stop the knock.

 

If I could just get my sh*t together all at once, I know it will run in the 11s now.

[wigenOut-S30]

yeah thoes 60 fts are not good. have you tried slipping the clutch out at around 2-2500 ? slip the clutch and use 3/4 throttle on launch and then after the launch floor it.. I was getting consistant 2.0 60fts wtih a 3.54 open diff and simi bald street tire. Now I have a 3.70 lsd and sticker tires.. we will see if that gets me a 1.9 or so.. sure hope so. Very nice times though.. I sm sure 11's are in your future if you get a good 60ft..

[Clifton]

I feel your pain. I went with a larger turbo and had 60' times like yours. I went from 2.0 with a small turbo to 2.4's with a larger one. I'm even think about going bigger still. I will go back out when it cools down a little here and try to get the launch right.

[evildky]

they tossed you running 12's with no ds hoop!? I thought you had to break 11's before needing shaft hoop!?

[Doug71zt]

KY - They tossed me last time out for running 26x9.5x16 slicks with no driveshaft hoop.

 

Wigen - I have a CF DF 240mm clutch in there right now, and it doesn't handle slippage very well. It will be replaced with a Clutch Specialites or ACT unit this winter when the new 3.0 goes in. Along with a Z31 tranny and a lightened 240mm flywheel. My 2nd gear syncro is hurting bad.

 

Also - I assume that you are launching on 15 inch rubber - correct? I'm running 17" with a short/stiff sidewall. They seem to either hook with minimal slippage or spin. I haven't been able to find that sweet spot in between yet. It may run better with a 3.54 LSD than the 3.70 that is in there now, I will find out next spring...

FWIW - I was racing a couple Talons for a lot of the night. (25+ passes). They could always get the jump, but 3rd gear seemed to reel them in just fine. It seems like nothing eats up the midtrack like a Z.

[Cody 82 ZXT]

I'm running 17" with a short/stiff sidewall. They seem to either hook with minimal slippage or spin.

 

I know what ya mean there running 245/40/17's I have gotten as low as 1.9 60' but, that was only once. As soon as I started getting some good launchs my tranny started to go south and would let me shift without some major grindage.

 

What what are you doing with the Z31 tranny? I gotta come up with a better answer than the current T5 and a trashed 3rd gear synchro.

[wigenOut-S30]

Doug, yeah I am running 15's i am sure that is a large help. Also I have a OEM turbo flywheel and clutch. I didnt even think if you had a CF clutch.. That would make it way hard to slip the clutch for sure.. At anyrate. great times man and good on ya for showing the DSMs what old school is all about..

[evildky]

I don't know how practicle they would be for you but have you tried drag radials? after a good smokey burnout they hook about as well as a slick, and it might keep the safty nazi's off your back

[Doug71zt]

Cody - I have a 87-89 Z31 turbo tranny which is very similar to the Z32 and skyline GTS-T, GT-R unit. It uses a huge output shaft and Ujoints compared to the early Z one. It also has double-cone syncros on 2nd and possibly 3rd gear(I can't remember). If I can't rework an L-series front housing to mount it up, I will probably mill the VG30 flange off of the bellhousing and weld an L-series flange in it's place. It has an integral shifter, and shifts much better than the early trannies.

 

KY- I have gone through a set of 245/50/16 Nitto 555R DR's and they will hook up well When Heated UP. They are no good when they are cold. But, they don't last real long when you fry them every run. When I go to the track, I generally make 20-40 passes a night. It turns out that the slicks are more economical, because they are cheaper to buy in Canada and they last a lot longer. I only have to give them a little spin to get the crap off and they are good-to-go. I just have to get down to it and make a hoop that mounts on the back of the tranny, so I don't have to drill the floor/move my 3inch exhaust, etc. to get a standard hoop in there. I'm not worried about the rear ujoint, as the DS won't drop past my sway bar anyway (custom shaft).

 

Wigen - It's not hard to slip that clutch - It's just that it won't hook up if you slip it off the line. I have to pretty much dump it, in order for it to hook. I don't think that I'm overpowering it, it is a Z31T/Z32NA clutch and 'allegedly' good for the HP I'm putting down. After owning 3 CF clutches over the years, I haven't been happy with any of them. Enough. They are very street-able, but they just won't take the abuse. Time for something industrial-grade. Especially with the new 3.0 and GT-series turbo.

 

I can't wait for next spring. I'm going to end up with something very close to Speeder's engine, but (no offense) in a car a little bit lighter. . BTW- Speeder - have you run your car at the strip since the new engine install?

 

Doug

[Jersey]

I think as well that 11's are yours once you get the little bugs out. Nice runs! I'm also interested in the Z31 tranny swap. Is it suppose to be stronger that the 82-83ZXT T5? My cousin just burned up his 2nd & 3rd gear synchros in the second T5 within 2 months! Stripped 3rd gear out of the last one. I've have no problems with my T5 but i'm not pushing as much torque as he is but, i think it's just a matter of time. Hey Doug, how are you launching on boost with the 5speed? I was thinking of a linelock but i'd hate to abuse my clutch like that. Thanks.

[speeder]

Doug,

 

No track time on the new engine yet - my day job and hurricanes have kept me from getting the thing together. Should be getting running in the next couple weeks.

 

The new 3.0 has had those Total Seal rings changed out for chrome rings because of oil control issues, and will come alive wearing the new .63 StageV/T04R .70 (25% more flow than my old T61) and 75 # injectors. Got to update my website!

 

Just can't seem to leave it alone!

 

I also will be running 275/40 - 17 Nitto 555R DRs for tires, and am expecting tranny breakage.

 

No offense taken about that weight remark - nothing that Mo' power can't cure.

[Scottie-GNZ]

I strongly recommend against 17" DRs if you are serious about cutting quick 60' times.

[Doug71zt]

I agree with you Scottie, I wish my Hoosiers were 15 inch, but they wouldn't clear my brakes then. Also, It's spooky enough with radials on the front and 12 psi in the slicks. I've learned that you don't chase the random wiggles and wallows with the steering. Not as bad as your little experience though.

 

Jersey - I have line-lock and I have used it to launch on boost with the slicks - but that is extreme clutch abuse. You have to be a master of co-ordination to hold the engine at 5.5K, feed it a little clutch, let the LL off and floor it on the last yellow. It all happens a little fast for me, who is an amateur drag racer. It leaves like a bigblock when you get it right, that's for sure. Personally, I think that the Z rear suspension launches pretty good on slicks. Street tires are different, as I get a bit of wheel hop sometimes when it spins out of the hole.

The late Z31 turbo tranny should be good to over 450 hp. It is pretty beefy and way heavier than the FS5W71B. Judging by how may T5's go to pieces, I think that even the FS5W71C Z31 NA tranny would be a better unit to use, unless you want to pump some serious $ into a WC upgrade or the like.

I'm thinking of jacking a 3speed auto into the car and seeing what it will do off the line when I can boost up against the convertor.

 

Speeder - Hope you get it together soon and put some miles on it. I'm curious what your times will be now. Nothing worse than redoing something that you have just finished with. Well, I guess a rod out the side of the block or something like that would be worse.

I have come to the realization that I should have gone with a Stage V/.63 on my hybrid, especially with the 60 trim T04E compressor I have. The Stage 3/.63 would be great with a 50 trim T04E for an all-around street, autox, track turbo. But to get the big HP #'s, the Stage V is the way to go. I've gone as far as I'm going with the T3/T04E stuff. My new turbo is a GT35R with a GT 40 compressor. Same 4" inlet, 2.5" outlet, .70 T04R compressor housing as you are now running.

I'm working at building a sheetmetal intake similar to yours, except with velocity stacks on the runners. How long are runners on your intake? Not looking to copy, but I think that mine will end up an inch or 2 shorter than factory.

 

Thanks for the support guys - It will be a long wait this winter. I'm overseas right now and I won't have the car out again this fall.

 

Doug

[Cody 82 ZXT]

The late Z31 turbo tranny should be good to over 450 hp. It is pretty beefy and way heavier than the FS5W71B. Judging by how may T5's go to pieces' date=' I think that even the FS5W71C Z31 NA tranny would be a better unit to use, unless you want to pump some serious $ into a WC upgrade or the like. [/quote']

 

Ever thought about adapting one of the Ford WC T-5's?

[speeder]

Scottie,

 

Seems that anything that gives more tread width will be an improvement on the 225/50-16s I have been using- but that 40 series is a really short sidewall.

 

I haven't bought DRs yet- I may have one more go at trying to find 15" wheels that will clear my rear brake calipers. Enter the classic dilemma - What compromises are you willing to make to optimise the car for one form of racing?

 

Doug,

 

The manifold is at the welder's - I'll measure those runners and let you know when it comes back. They are at least 2" shorter than factory.

Love those ball bearing turbos - maybe I should have saved some more $ and got one like yours.

[Doug71zt]

Cody - I've rebuilt quite a few T5's from 80's Camaros and Mustangs. I built and ran a T5 equipped S-10 Blazer for years with a 327/275 that was later swapped out for an original LT-1. I have no love for T5's. I know, I know - the WC units are much better than the first run, people keep telling me that - but I like how well made the Nissan trannys are. True, there is only so much power you can run through that size of gear, as Tim has found out, but I think that I will try the Z31 tranny first. The z31 guys are having good luck with them, and the Z31 is a pig compared to the S30. Besides, I have one sitting in the shop - so there will be no cash outlay...

 

Speeder - Thanks for the response on the manifold. Are you modifying it already?(at the welders). A tire option for you would be to run the same slick as I bought - Hoosier QTP 26x9.5x16. You won't have any traction issues with those babies. You may, however, have tranny troubles.

[Clifton]

Speeder.... Keizer wheels have alot of room for a 15" wheel. I have them with the 11.2" Wilwoods and they clear no problem, don't know of any street wheels that will.

[Scottie-GNZ]

Compromise. You hit the nail on the head and it is not just "handling" vs drag race, but also everyday street driving. The only tire that can come close is the Nitto 555R DR and with your flares, the 275/50-15 is the best bet. It has excellent street manners, good "handling", is not an issue in the wet, can last close to 10K miles, and is excellent at the drag strip. The only 15" wheel I know that will fit huge brakes is the Weld Draglite and Pro-Star XP series, but the style might not be what you want. I was able to run mid-1.50s with the 15" Nittos but could spin the 17s for over 300'. A switch to 26x9.6x16 Hoosier QTPs get me low-1.40s. Ironically, the more power/torque you make the more you end up losing at the strip with compromise tires if you really lay into them hard off the line. The torque from your 3.0L will make the 17s useless at the strip.

 

Initially regretted the expense and PITA of running multiple tires for the street and strip but the results at the strip was worth it. The best setup for the strip would be the QTPs but I absolutely do not recommend them for the street as they are bias-ply and require bias-ply fronts, have no treadwear and will spin you out if someone in front of you spits on the road. I think you need to ask yourself (HONESTLY) how is the car really going to be used, despite how it looks like it will be used. I think the answer will be street driving and drag racing. Question is, how quick do you want to go? I personally think your car has the potential to dip into the 10s, but what compromises are you willng to make to achieve that?

[speeder]

Doug,

 

No mods, just redoing the throttle cable attachment.

 

Clifton/Scottie,

 

Thanks for that- my rears are wilwood 11.2s. I was beginning to think about some sort of non-street 15" wheel wth rims made of thinner stuff to clear. I think that's the direction I will go - 275/50-15 - I've obtained adaptors to enable a 5X4.5" bolt pattern, so wheels and tire choices should be plentiful. Style is really not an issue with race tires.

 

Scottie,

 

Although I've done very little racing (I've been around racing most of my adult life as crew/mechanic/pit slave), I've always had the goal of building a car for myself that does all things well. Thinking about compromises, If you can optimise the car for drag racing by a wheel/tire change and easy suspension adjustments such as camber/ sway bar tweeks, then back to street, then set for up roadrace/ autox just as quickly, you don't have to live with any half measures. The PITA comes when the setup for each use is difficult or time consuming.

 

I've even had some thoughts about making a low- boost, high advance calibration for the E-motive that would make the car more manageable on a road course. Again, a quick and easy change, and just as quick to change back.

 

I don't envision the whole setup process (suspension engine management) and taking more than an hour for any configuration.

 

Good street manners and easy "configurability" have been the appeal of a well set-up turbo car for me.

 

10s? Let's do 11s first.

 

Hey, i thought this topic was turbine housings!

[Lockjaw]

I am not surprised about the housing causing you to go a little slower on the launch, my increasing to a stage V from a stage lll made a DRAMATIC difference. Where I used to be able to blow off street tires at will in first or second, well that doesn't happen as much with the larger wheel.

 

However, if I break the tires loose, its all over the limiter, and the power from midrange on up is superior. You have to find the sweet spot, for me, it seems launching around 3500 and just dropping the clutch seems to get me moving before the serious boost hits, and the car leaves and runs 1.90 60 foots on drag radials, with full air pressure. I never did try to run it dropped before I blew the HG.

 

Also the CF clutch is a POS. I am going to get an ACT eventually. I am unmotivated right now.