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BeeZnutZ1979
11-05-2016, 11:43 AM
My name's Brandon and I'm from northern Indiana, here's some back story on my daily driven spirit rt family fun car.

Well I've spent most of my time over on the other turbo dodge site and recently found out how much more interesting this site is compared to the other one soI figured I'd throw my little project log up here. I had a few td's back in the late 90's and did everything all wrong which led to breaking everything from pistons to transmissions. After getting married and having two kids I decided I needed some boost back into my life. It took my a bit but ended up picking up a 90 Daytona es with a 2.5 T1 auto. Well after driving this car for a few months I came to realize it needed alot of work to handle any kind of boost increase. So I decided I needed to find a car in better shape to drive while I worked on my Daytona.

So I looked and looked and ended up finding a really nice 88 turbo Z and also a really clean 91 spirit rt both within an hour froim my house. So the decision was to be made wether to go with the 8 valve smec tii Daytona or the 16 valve sbec tiii spirit. I talked to alot of people and almost everybody said to stay away from the tiii and just go the safe route of the 8 valve. Then I started talking to Jackson and he made me feel much better about going the tiii route. So I headed down to check the spirit out in person. I like how my Daytona looks but something about the styling of the spirit rt really made me want to own it. Then came the test drive. It only took half throttle and a few years and my mind was made up, the spirit was coming home with me. Got the car home and parked it for the first few months so I could thoroughly go through all the problem areas I was warned about before I started daily driving it.

The mileage is unknown, odometer stopped working at 113,000. The car had 3 inch exhaust that stops just after rear axle with no muffler only a 3 inch catco cat. Stage 1 ND cal and +20 injectors and a k&n air filter when I bought it running about 14 psi. Only other parts were a b&m short shifter and a boost gauge. Here's a picture of when I picked it up, not much has changed on the exterior, all the changes have been under the hood. The car came frmom the north east originally, I think Connecticut, then was owned by goose in Virginia and a guy from Norwalk Ohio had it before the guy I bought it from. It has now found its forever home!

BeeZnutZ1979
11-05-2016, 11:56 AM
https://youtu.be/sasutMN6nPo
Here's how it's running as of last week, I'll get to all the details if there's any interest.

1BADVAN
11-05-2016, 01:07 PM
Awesome run, what turbo / boost are you running

BeeZnutZ1979
11-05-2016, 01:18 PM
Current turbo is a modified holset 351 with homemade 3.5 inch down pipe running 18 psi. On 93 octane.

BeeZnutZ1979
11-05-2016, 01:26 PM
Here's the time slip for that run, I think I can skim a few tenths off my short time to get me lower into the 12's, this was only my second time to the track with a FWD manual turbo car, all my previous drag cars have been rwd. Also planning on some more boost and a few other tricks next year.

1BADVAN
11-05-2016, 05:27 PM
that's great on 18 psi! Pump gas? What kind/ size of IC do you have? This is exactly what i want a 12 second car on less than 20 psi way to go!

BeeZnutZ1979
11-05-2016, 06:02 PM
Yeah I'm pretty happy with how it performs now, I had the exact setup that I'm running now but the stock Garret turbo and it ran a 13.5@104 mph. Switched to the holset and stayed at 18 psi and pulled the 12.6@111 mph, I can definitely tell that the motor is breathing easier through the holset than the little Garret. And yes I run 93 octane pump gas, the intercooler is just a cheapo cx racing cooler I bought off of eBay. It's a dual pass intercooler thats 29 x 10 x 3.5 inches thick,had alot of people tell me there junk but it's working great for me and installed really simply in my car. I was going to turn the boost up more and try to go a little faster but was starting to run a bit lean towards the end of the track, never had the fuel pump out but I believe it's just a stock pump.

Wastelands Warrior
11-05-2016, 08:22 PM
Spirit R/Ts make excellent family cars!

BeeZnutZ1979
11-05-2016, 08:30 PM
Yes they do, my daughter's love the way daddy drives when mommies not around, lol

Wastelands Warrior
11-05-2016, 09:33 PM
^^^That's cool. Mine gets driven daily up until the snow flies

BeeZnutZ1979
11-05-2016, 10:09 PM
Same here, only time I break it out in the winter is if the roads are clear and salt free, got to keep the body nice since I plan on having it the rest of my life.

Wastelands Warrior
11-05-2016, 10:17 PM
Same here, only time I break it out in the winter is if the roads are clear and salt free, got to keep the body nice since I plan on having it the rest of my life.

I'm with you on that. I'm liquidating my other projects in order to build the R/T.

BeeZnutZ1979
11-05-2016, 10:38 PM
What kind of build are you going for? Here's a under hood pic of my rt, basically just 3 bar map and FWD stage 4 cal, +40 Injectors, afpr, fmic and a holset turbo with 3.5 inch downpipe and 3 inch exhaust. I've also got a few Jackson pieces, like modified valve spuring retainers, idler mod and a short throw shifter. Also relocated my battery to the p/s and built this cold air box where the battery originally was that sucks air from outside the engine bay.

tryingbe
11-05-2016, 10:53 PM
It's a dual pass intercooler thats 29 x 10 x 3.5 inches thick,had alot of people tell me there junk but it's working great for me and installed really simply in my car. I was going to turn the boost up more and try to go a little faster but was starting to run a bit lean towards the end of the track, never had the fuel pump out but I believe it's just a stock pump.

This person has a dual pass, boost drops was 13psi.

http://www.turbo-mopar.com/forums/showthread.php?62578-1986-Glh-omni-2-5-holset-build&p=995200&viewfull=1#post995200

His intercooler was bigger than yours.
http://www.turbo-mopar.com/forums/attachment.php?attachmentid=45177&d=1369406934

Wastelands Warrior
11-05-2016, 11:26 PM
What kind of build are you going for? Here's a under hood pic of my rt, basically just 3 bar map and FWD stage 4 cal, +40 Injectors, afpr, fmic and a holset turbo with 3.5 inch downpipe and 3 inch exhaust. I've also got a few Jackson pieces, like modified valve spuring retainers, idler mod and a short throw shifter. Also relocated my battery to the p/s and built this cold air box where the battery originally was that sucks air from outside the engine bay.

Mine is pretty much like yours. I have a Jackson Holset set up as well. Just want to build the engine to take whatever I want to throw at it.

wheming
11-06-2016, 06:32 AM
Here's the time slip for that run, I think I can skim a few tenths off my short time to get me lower into the 12's, this was only my second time to the track with a FWD manual turbo car, all my previous drag cars have been rwd. Also planning on some more boost and a few other tricks next year.

With no changes other than some good slicks (like my favorite M&H Racemasters ) you should be able to get 60' times down to 1.80, which would make your 12.65 more like 12.2!

And as tryingbe mentioned, the bad part about the 2-pass intercoolers is they are restrictive (however that can make for good temperature drop -heat transfer) but that means there is significant pressure drop across them. You should try to measure how much boost pressure you have before and after your intercooler.
(Simply try to get a boost gauge reading turbo outlet, and you probably have boost reading at your intake manifold already.)

BeeZnutZ1979
11-06-2016, 08:24 AM
I can see how they would be more restrictive than a single pass but what would be the disadvantage of pressure loss? Obviously my turbo is capable of pushing way more than 20 psi. So even if pressure is above that pre intercooler there's no way I'm overspinning it trying to reach my desired boost level. Plus I'm about as far with this car as I plan on taking it, no need to sqeeze every last drop of power out if it, a 12 second family car is cool enough for me. I have a Daytona drag project car for pushing the limits with which has a single pass intercooler.

wheming
11-06-2016, 11:48 PM
Downside is just the turbo is working harder, and if you kept trying to increase boost in the intake, then you could be outside the design limits of the turbo.
It is work the turbo is doing, with not much gain due to restriction in the intercooler.
But i think it is great you are turning those numbers with that setup! Like i said, the temperature drop across it is probably good.

Keito
11-07-2016, 07:41 AM
I wondered what happened to this car, I knew the guy in Norwalk that had it.
Looks like you worked the bugs out of it.
If my memory serves me correctly, when he got it from Goose, he couldn't figure out why it was throwing the timing belt, turned
out the timing gear on the crank had a big chunk taken out of it.
Did he ever get it running before he sold it to you?

BeeZnutZ1979
11-07-2016, 08:37 AM
Yep, this is that car, From what I read he got it running and then it blew a crank seal and he parked it. Then a guy local to me bought it and changed the int. Shaft bearings and put new crank and int. Shaft seals in it and drove it a few hundred miles before putting it up for sale. After I bought it I parked it and went through it as best I could and fixed a number of things. I've been driving it almost daily since this spring, put about 5,000 miles on it this year so far, loving every minute of it, like I said it's now found its forever home.

wheming
11-07-2016, 12:15 PM
That's a fortunate turn of events that brought it to a good home, rather that suffer the fate of a part out from loosing interest.
Good on you!

GLHNSLHT2
11-07-2016, 08:58 PM
Yeah I'm pretty happy with how it performs now, I had the exact setup that I'm running now but the stock Garret turbo and it ran a 13.5@104 mph. Switched to the holset and stayed at 18 psi and pulled the 12.6@111 mph, I can definitely tell that the motor is breathing easier through the holset than the little Garret. And yes I run 93 octane pump gas, the intercooler is just a cheapo cx racing cooler I bought off of eBay. It's a dual pass intercooler thats 29 x 10 x 3.5 inches thick,had alot of people tell me there junk but it's working great for me and installed really simply in my car. I was going to turn the boost up more and try to go a little faster but was starting to run a bit lean towards the end of the track, never had the fuel pump out but I believe it's just a stock pump.


This person has a dual pass, boost drops was 13psi.

http://www.turbo-mopar.com/forums/showthread.php?62578-1986-Glh-omni-2-5-holset-build&p=995200&viewfull=1#post995200

His intercooler was bigger than yours.
http://www.turbo-mopar.com/forums/attachment.php?attachmentid=45177&d=1369406934


With no changes other than some good slicks (like my favorite M&H Racemasters ) you should be able to get 60' times down to 1.80, which would make your 12.65 more like 12.2!

And as tryingbe mentioned, the bad part about the 2-pass intercoolers is they are restrictive (however that can make for good temperature drop -heat transfer) but that means there is significant pressure drop across them. You should try to measure how much boost pressure you have before and after your intercooler.
(Simply try to get a boost gauge reading turbo outlet, and you probably have boost reading at your intake manifold already.)


I can see how they would be more restrictive than a single pass but what would be the disadvantage of pressure loss? Obviously my turbo is capable of pushing way more than 20 psi. So even if pressure is above that pre intercooler there's no way I'm overspinning it trying to reach my desired boost level. Plus I'm about as far with this car as I plan on taking it, no need to sqeeze every last drop of power out if it, a 12 second family car is cool enough for me. I have a Daytona drag project car for pushing the limits with which has a single pass intercooler.


Downside is just the turbo is working harder, and if you kept trying to increase boost in the intake, then you could be outside the design limits of the turbo.
It is work the turbo is doing, with not much gain due to restriction in the intercooler.
But i think it is great you are turning those numbers with that setup! Like i said, the temperature drop across it is probably good.


An air/air is only going to pull so much heat out of the system. If you took your i/c and make it a single pass the air would move 1/2 as fast through it so it would cool the same with 1/2 the pressure loss. On top of that it has to make a 180 degree turn to go the other way. So now you've slowed down the air, and dropped the pressure loss. And lets use a 13psi pressure loss and a 18psi intake pressure. So your turbo has to spin to make 31psi. This means the compressor is pumping more heat into the air which taxes the i/c more. On the exhaust side you've noticed how going to a bigger turbo has helped the car breathe. Now imagine if instead of opening the WG at 31psi you could open it at 18!!! And how much farther it would open to keep the boost lower. Lower compressor speeds means cooler air so the i/c doesn't work as hard which will lower your intake temps. Lower turbine speeds means more flow sooner. which all equals more hp. A slightly larger single pass unit with a 1-2psi pressure drop or less and you could probably hit 11's@18-20psi with good traction. Our points is that you're leaving a HUGE amount of hp on the table with that i/c. T3's like lots of flow and you saw this with the turbo upgrade. Now you need to upgrade your intake side. You've upgraded everything else for flow then stuck a cork in the system.

BeeZnutZ1979
11-07-2016, 09:23 PM
Ok, I have thought about cutting the end tanks off and making a single pass out of it. I'll weld a fitting in the intercooler tube pre cooler and get some readings to see how much pressure loss I'm actually dealing with, if it's to much I'll modify my cooler or buy a better one, thanks for the advice!