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Discussion Starter #1
Despite all the comments that my 3.8L would eat its head gaskets and the torque converter.

Things that helped
- I had the car running well as a car before entering the race. It takes forever (30min) to load up 171ish cars into a grid to start and several died and had to be pulled out of the grid because they were left idling for so long. I think it was a survival test :)
- my homemade monitor system/mister systems made sure that our ATF temp never went beyond 180F and the Coolant beyond 235F (mostly at 210F).
- we made sure all drivers left OD-off and tried to get the car into 3rd as often as possible (the lubricated gear as opposed to 1st and 2nd). This prevented any 3-4 shifts @ WOT which are deemed bad b/c of how the transmission engages 4th.
- the JMODed our 4r70w and added a new solenoid and pressure regulator valve as per the suggestions. The transmission was harsh but driveable and launched immediately vs. hesitating (which was what happened when I first got the car).

Problem/Observation I could use some insight on...
Under load, the engine had a hard time revving beyond 4K and the transmission didn't want to upshift. It's like the hamsters smoked too much and ran out of energy. For reference, with our 3" smaller diameter tires and 3.73 rear gears, our effective final drive ratio was 4.20:1. I suspect the shift points are in the 4K-5K range for WOT and our powerband stops at 4K -- thereby creating this situation. In order to get into 3rd, we learned to back off the gas pedal, allow the shifting to occur, and then push it down again. This sometimes occured at the most inopportune time (i.e.: right as we were overtaking someone on the turn b/c we have a nice neutral handling and they were hopped up jalopies).

Q: Is there something we can do to rectify this situation for the next race?
Thoughts:
- We cannot go back to 3.27 gears (we used the pinion gear as a sledge so it's well and truly biffed). I "didn't fear the gear" and did notice that with just the smaller tires and stock diff (3.68:1 effective ratio), our 1/4 mi time dropped from 17.95sec to 17.05 sec.

- Hotter cam? What other issues will I run into?

- If we do go with a 4.2L V6, can we just use the F150 ECU, will it run with my stock ECU, or will I need to burn a custom ECU? The reason I ask is because ECU tunes are often expensive (not really -- but out of Lemons budgets).

- ECU tune just to lower shift points?

I'm already planning on putting the car on even more of a diet. We had it down to 3500 w/ full fluids, driver, and trunklid but its quite clear that we need to drop more.

The other thought is to not abandon this platform altogether (we've got too much into it) but to skip the arms race on the GO part and aim for the "show" -- i.e.: add more sheetmetal/bondo and whatnot to deploy a really sweet theme for our next entry. If we do this, we would stand a better chance of getting the Index of Effluency Prize.

If you guys have any suggestions on a sweet theme, please PM me. It appears that our target audience, the judges, are guys in their 40s-50s to the thundercats was a bit young for them.

Regards,
-g
 

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Will the engine rev above 4K in any gear? What are you running for exhaust? If you still have cats on it, maybe they are clogging up. What are you using for the speedo calibration with the steeper gears and smaller tires? That might be causing problems because if the ECM doesn't know how fast the output shaft is going, it can cause a lot of weird shifting issues. I would start by deleting the cats if they are still on there, and if that doesn't solve the problem, get a speedcal and see if that helps. I wouldn't abandon the platform after one race. It took us till our 3rd race before we had a clue what we were doing. If you kept the car running through your first race, and didn't crash, and didn't spend half the time in the penalty box, I would consider that a step in the right direction. Sort out your trans issues, or if that fails, go with a 5-speed, and run it again to see what your next problem will be. I would pretty much forget about the IOE with that car, but with some work, and if you can keep it on the track the whole race, you might be able to pull off a least horrible yank tank.
 

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Discussion Starter #3
1) I need to check but it didn't seem to have problems revving in neutral or from 1st to second.

2) Exhaust is a stock cherry bom. Cats are still on the car b/c of emissions and a desire to keep the car street legal. When I smogged the car, the emissions were quite low so the cats shouldn't be clogged at all.

3) I corrected the speedo with a 23 tooth speedo gear and not a speedcal. I believe that brings
me down to only 18% off of the real speed (+ for the tires, + for the gears, - for the speedo gear). Interesting comments about the shifting problems.


4) We kept the car running the whole time. By our calculation, we spent way too much time swapping drivers because a) we wanted to give all drivers a chance and b) we didn't know what we were doing as much. 3 hours too much time so there's definitely room for improvement here. Our only black flag was b/c one of my drivers drove too fast in the pits, cut through the penalty box, and parked it in the wrong spot when we came back for our punishment (next to the sign that said penalty box, not all the judges). IMO, this clearly showed that we were clueless so they let us go with a slap on the wrist. Next race, if there is a next race, we'll run the car with less drivers and spend more time in the car (90min-2 hr stints vs. 30 in the beginning and 1.25 hrs on day 2).

-g
 

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Forget the 4.2 splitport for now, go 5 speed. Better acceleration in turns, and its lighter. The car will definitely feel faster with the 5 speed even with the single port v6.
 

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I have a car here I am parting out that has been split port converted and the shortblock is bad. Heads may need to be redone but it is a 96 and has the pcm and wiring harness too and best of all It would be cheap. I would guess $500 shipped for everything you would need would be fair but I need to check shipping to make sure it won't be over about $100
Alan
 

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I have a car here I am parting out that has been split port converted and the shortblock is bad. Heads may need to be redone but it is a 96 and has the pcm and wiring harness too and best of all It would be cheap. I would guess $500 shipped for everything you would need would be fair but I need to check shipping to make sure it won't be over about $100
Alan
you know they have a budget of $500 right?
 

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Discussion Starter #7
Thanks for the offer Alan but I need to think things over. I haven't checked how much of a residual they would give me for the next race (they give you a certain amount depending on what you want to do next). It may be worth it to me (under the rules), to acquire MORE of a donor vehicle and then sell off bits to bring the value of what I'll install down.

Other than that, I guess it's a question of how much I want to cheat. As it stands right now, they seriously spend <30 seconds looking underneath my tbirds hood. I still need to decide if more power is the way we want to go.

You'd be surprised how many cars showed up that were super cheaty. For example: I'm glad the driver was safe but one car that was totally was a Saturn from a pair fielded by a NASCAR pro-west team. They plowed into another super cheaty Camaro that had stopped around a bend and totalled out their car (well, one of them). The funny part is, and this is total Schadenfreude here, was that the NASCAR team must have had 15-20K into the Saturn -- you could tell by the fancy-pants coilover suspension peaking out of the wreck + the paint job. God knows what they had into the engine. There was NO way those cars came in under $500.

-g

Q: What needs a new ECU/tune to run effectively and what can I run with my existing 3.8L NA ECU? is there anything I can do to make the car run effectively without dumping cash into a new ECU?

4.2L swap?
3.8L + Split port intake/heads?

These may be noob questions but from what I've read on this site (yes, I've read the main splitport threads), it sounds like all I would need to make the split port operate is an external RPM controlled switch for the IMRC. Will the original ECU compensate for the different airflow (vs. a stock intake) or will it just run really lean?

Finally, what about the M5R2 5 speed conversion? Will that work with the existing ECU since AFAIK, no 3.8L N/A came with a 5speed?

Thanks for your replies.
-g
 

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Your current ECU can be retuned with a chip to make it run pretty much any V6 engine. It would get a little cheaty, but would not be something they would notice. The M5R2 5-speed trans out of an SC will bolt right up to a 3.8. Without a tune, the check engine light will be on because the ECM will be looking for a bunch of transmission inputs that it won't see. I don't know if it would affect drivability at all though.
 

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These may be noob questions but from what I've read on this site (yes, I've read the main splitport threads), it sounds like all I would need to make the split port operate is an external RPM controlled switch for the IMRC. Will the original ECU compensate for the different airflow (vs. a stock intake) or will it just run really lean?

-g
You won't need an RPM switch if you get an intake without the IMRC, 1999-2000. You can run the stock 14lb injectors, not sure if it will run lean though. Stock splitports ran 19s.

Joe
 

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Thanks for the offer Alan but I need to think things over. I haven't checked how much of a residual they would give me for the next race (they give you a certain amount depending on what you want to do next). It may be worth it to me (under the rules), to acquire MORE of a donor vehicle and then sell off bits to bring the value of what I'll install down.

Other than that, I guess it's a question of how much I want to cheat. As it stands right now, they seriously spend <30 seconds looking underneath my tbirds hood. I still need to decide if more power is the way we want to go.

You'd be surprised how many cars showed up that were super cheaty. For example: I'm glad the driver was safe but one car that was totally was a Saturn from a pair fielded by a NASCAR pro-west team. They plowed into another super cheaty Camaro that had stopped around a bend and totalled out their car (well, one of them). The funny part is, and this is total Schadenfreude here, was that the NASCAR team must have had 15-20K into the Saturn -- you could tell by the fancy-pants coilover suspension peaking out of the wreck + the paint job. God knows what they had into the engine. There was NO way those cars came in under $500.

-g

Q: What needs a new ECU/tune to run effectively and what can I run with my existing 3.8L NA ECU? is there anything I can do to make the car run effectively without dumping cash into a new ECU?

4.2L swap?
3.8L + Split port intake/heads?

These may be noob questions but from what I've read on this site (yes, I've read the main splitport threads), it sounds like all I would need to make the split port operate is an external RPM controlled switch for the IMRC. Will the original ECU compensate for the different airflow (vs. a stock intake) or will it just run really lean?

Finally, what about the M5R2 5 speed conversion? Will that work with the existing ECU since AFAIK, no 3.8L N/A came with a 5speed?

Thanks for your replies.
-g
Since I did both, the 5 speed swap and then the splitport swap, I would recommend just doing the 5 speed swap. The splitport swap has a increase in hp but the torque is about the same. Honestly, I wasn't really impressed with the splitport swap but then again mine is untuned and I'm running the stock 14lb injectors. I was more impressed when I put a M5r2 behind the singleport, better acceleration, power, mpgs, etc. I believe you would have to tune the ECU for the 5 speed swap since your car is a 95. With the AOD, mine was just plug and play with all the wiring already there.
 

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Discussion Starter #11
Thanks for the inputs Bay_Bird93 but has anyone with a 3.8L and an 4r70w-targeted ECU (95-97) tried doing a 5speed swap?

Also, what should I be looking at cost-wise for the swap?
I've read this DIY several times but I don't have a good feeling if this can be done for Lemons money (or close enough where I can massage the numbers to work and/or sell my old 4r70w.)
http://sc.tbkhomeworld.com/walkthrough/aodto5speed/#6
http://www.tccoa.com/articles/tranny/transwap.html


I don't care about the CEL as much as I do about engine driveability (something not happening or going into a limpmode b/c I am using my original ECU).

Regards,
-g
 

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I would suspect any drivabilty issues would be part throttle issues, not WOT, but that is based on my experience with 5-speed swapped 4.6 cars, so I don't know if the 3.8 would be the same. A simple test you can do, assuming the car is still road legal, is take it somewhere like a business park on a Sunday or somewhere that you can test drive the car a reasonable speed without being in someone else's way. Drive around with the shifter in 2nd gear, note how it drives, how it performs, etc. then unplug everything off the trans except the speedo, which will make it default to 2nd gear, and drive it around again and see if you notice any differences. If not, then you know the trans inputs being missing will not affect the engine controls. If you start having other issues, then you know you would need a tune for your 5-speed swap.

As far as getting the swap done under budget, find yourself a wrecked or rotted out SC as a donor car. Figure if you can get a complete car for $400, even if you don't sell anything off it, you can recoup most, if not all of your money when you scrap the shell.
 

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Thanks for the inputs Bay_Bird93 but has anyone with a 3.8L and an 4r70w-targeted ECU (95-97) tried doing a 5speed swap?

Also, what should I be looking at cost-wise for the swap?
I've read this DIY several times but I don't have a good feeling if this can be done for Lemons money (or close enough where I can massage the numbers to work and/or sell my old 4r70w.)
http://sc.tbkhomeworld.com/walkthrough/aodto5speed/#6
http://www.tccoa.com/articles/tranny/transwap.html


I don't care about the CEL as much as I do about engine driveability (something not happening or going into a limpmode b/c I am using my original ECU).

Regards,
-g
Unfortunately, it looks like you would need a tune to get the 5 speed to work right. Cost-wise you could buy a SC parts car like Mikey said or maybe try pick n pull when their having one of their once in a blue moon 50% off specials. You could probably get everything for maybe $300-400 depending on what you want new and what you would just throw on there.
 

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Discussion Starter #14
1.25 years later, I finally figured out why my tbird wouldn't rev beyond 4250 RPM. I'm updating this thread for the sake of others who may have encountered similar issues.

Short answer: check your engine ignition timing!

* At first, I thought it was the automatic transmission acting screwy. I then swapped out the auto for an m5r2 and the problem persisted.
* Next, I thought maybe the exhaust was too restricted (perhaps a cat was clogged) and was choking the engine. I traded my exhaust for a true dual setup. The problem persisted.
* Next, we upgraded the top half of the engine with splitport bits. This should have solved a situation where the intake was too restricted. The problem persisted.
* What finally persuaded me to check out the timing (besides MadMikeyL's suggestion) was that we started logging/examining the data from the various sensors on the car. This included
- The MAF was not being maxed out at 5V at the limit
- The injector duty cycle wasn't dropping at the limit (to coincide with the computer cutting off fuel)
- When I checked the timing with a gun, it appeared that my timing was set to ~30 degrees advance (vs. 10 where it should have been set)
- Furthermore, I checked the timing-related jumpers and found that the Spark Out Jumper was gone (with this jumper, the ECU will NOT advance timing).
- NOTE: Only SCs and California cars will have a second timing-related jumper that retards timing by 3 degrees in case you run lower octane fuel.

Once I figured out that my timing was out of whack, fixing this problem becomes merely a matter of loosening one bolt and rotating the distributor assembly CCW as a way to reduce timing. Dan helped me the first time and I was able to tweak it further later.

I hope this helps anyone else with a similar issue who actually uses the SEARCH feature of tccoa.com

-g
 

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I always go back and post the reason for something I've had a problem with.

When it happens again, 5 years from now, I won't have to wonder what fixed it last time. :D
 
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