Tuning for TPI
Thread Starter
Racer
Joined: May 2014
Posts: 290
Likes: 66
From: Chicago Illinois
Tuning for TPI
Hello, I have a Speed Density car I put a new motor in. It has an aggressive cam in it and I am having some issues with the idle. The person that did the engine swap has given up on trying to get the tune right is there somewhere in the Chicago area that can tune an OBD I SD car?
Advanced
Joined: Jul 2017
Posts: 52
Likes: 10
What equipment were you using before and were you altering the prom or swapping chips?
It is a huge undertaking for a beginner to learn about tuning and to do it yourself but it is possible. And if you still run a 350 then it really isn't that bad. Some say if your cam is too big then the tpi can't handle it but don't have the discussions and the evidence to link at the moment. I used equipment from moates.net and their guides and resources.
It is a huge undertaking for a beginner to learn about tuning and to do it yourself but it is possible. And if you still run a 350 then it really isn't that bad. Some say if your cam is too big then the tpi can't handle it but don't have the discussions and the evidence to link at the moment. I used equipment from moates.net and their guides and resources.
Racer
Joined: Aug 2008
Posts: 388
Likes: 116
From: Jackson Michigan
Hello, I have a Speed Density car I put a new motor in. It has an aggressive cam in it and I am having some issues with the idle. The person that did the engine swap has given up on trying to get the tune right is there somewhere in the Chicago area that can tune an OBD I SD car?
John
Team Owner
Joined: Jul 2004
Posts: 28,424
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From: Hartford WI
Drifting
Joined: Jun 2018
Posts: 1,678
Likes: 229
From: Michigan
What equipment were you using before and were you altering the prom or swapping chips?
It is a huge undertaking for a beginner to learn about tuning and to do it yourself but it is possible. And if you still run a 350 then it really isn't that bad. Some say if your cam is too big then the tpi can't handle it but don't have the discussions and the evidence to link at the moment. I used equipment from moates.net and their guides and resources.
It is a huge undertaking for a beginner to learn about tuning and to do it yourself but it is possible. And if you still run a 350 then it really isn't that bad. Some say if your cam is too big then the tpi can't handle it but don't have the discussions and the evidence to link at the moment. I used equipment from moates.net and their guides and resources.
Thread Starter
Racer
Joined: May 2014
Posts: 290
Likes: 66
From: Chicago Illinois
What equipment were you using before and were you altering the prom or swapping chips?
It is a huge undertaking for a beginner to learn about tuning and to do it yourself but it is possible. And if you still run a 350 then it really isn't that bad. Some say if your cam is too big then the tpi can't handle it but don't have the discussions and the evidence to link at the moment. I used equipment from moates.net and their guides and resources.
It is a huge undertaking for a beginner to learn about tuning and to do it yourself but it is possible. And if you still run a 350 then it really isn't that bad. Some say if your cam is too big then the tpi can't handle it but don't have the discussions and the evidence to link at the moment. I used equipment from moates.net and their guides and resources.
https://www.high-performance-engines...ine-p/hp89.htm
I have 30lb injectors, ported plenum, TPIs big mouth intake, ASM runners, headers it's also a manual transmission. In order to keep it running smooth he set the idle to 925 rpm. It drives great other than the idle issue.
Last edited by Steves LS6; Aug 21, 2018 at 11:52 AM.
Thread Starter
Racer
Joined: May 2014
Posts: 290
Likes: 66
From: Chicago Illinois
Try Scott Hansen (http://www.scotthansen.net/). He was able to tune my 78 CJ7 with an 88 IROC-Z TPI. I had idle problems because my Jeep is a manual, and the computer was set up for an automatic. He’s really sharp and if he can’t do it, I’m sure he can point you to someone who can. Good Luck!
John
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Burning Brakes
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From: Houston TX
Thread Starter
Racer
Joined: May 2014
Posts: 290
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From: Chicago Illinois
When he gave me the car back the idle was at 850 rpm. At that rpm it was running rough, and surging. When the fan would turn on it would die. Now the idle is set at 925 rpm and when the fam turns on it will run rough till the fan turns off. It also runs rough when I turn the A/C on.
Team Owner
Joined: Jul 2004
Posts: 28,424
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From: Hartford WI
When he gave me the car back the idle was at 850 rpm. At that rpm it was running rough, and surging. When the fan would turn on it would die. Now the idle is set at 925 rpm and when the fam turns on it will run rough till the fan turns off. It also runs rough when I turn the A/C on.
Drifting
Joined: Jun 2018
Posts: 1,678
Likes: 229
From: Michigan
Are you doing any scanning, what is your 02, Cross counts, and BLMs telling you?
If you have proper data logging and long term data from driving, it is not a "guess" tune". The "guess" may be where the starting point is, but even your Dyno tuning guy will have to start somewhere too and he will log data during the run. Make adjustments and do another pull. If your mail order guy is willing to read your data logs and make adjustments, it is essentially the same deal without the nice graph of before and after.
Team Owner
Joined: Jul 2004
Posts: 28,424
Likes: 3,276
From: Hartford WI
Agree, as I said above... the extra RPM will help with air velocity. The other part of it is running a elevated fuel pressure to help atomize the fuel. If your injector is too large, you might not be able to get a good mixture with atomized fuel.
If you have proper data logging and long term data from driving, it is not a "guess" tune". The "guess" may be where the starting point is, but even your Dyno tuning guy will have to start somewhere too and he will log data during the run. Make adjustments and do another pull. If your mail order guy is willing to read your data logs and make adjustments, it is essentially the same deal without the nice graph of before and after.
If you have proper data logging and long term data from driving, it is not a "guess" tune". The "guess" may be where the starting point is, but even your Dyno tuning guy will have to start somewhere too and he will log data during the run. Make adjustments and do another pull. If your mail order guy is willing to read your data logs and make adjustments, it is essentially the same deal without the nice graph of before and after.
Agreed. The "guess a tune" I am referring to are those that write a tune based on what you said you have and go with that. Without data logs, it is guessing, IMO. Sure, he can be responsible and backpedal it a little so as to have safety or go as far as he dares and increase the risk of something going wrong. Actually, I do like to see the before, after and DURING. That tells me you are pushing it to max power and back off once it goes over the top and correlate that with the ECM readings for best results.
Thread Starter
Racer
Joined: May 2014
Posts: 290
Likes: 66
From: Chicago Illinois
He does have data logs and I’ll see if I get him to post some. He has built and tuned many TPI’s according to him the SD cars are much more difficult to tune than the MAF cars. I am guessing it could be that the IAC is bad. It is the original one to the car.
There are people with similar motors and they are running 50lb injectors. From what my reasearch has showed me these people get their cars to run correctly.
This is a learning process for me and I appreciate all the responses.
There are people with similar motors and they are running 50lb injectors. From what my reasearch has showed me these people get their cars to run correctly.
This is a learning process for me and I appreciate all the responses.
Team Owner
Joined: Jul 2004
Posts: 28,424
Likes: 3,276
From: Hartford WI
He does have data logs and I’ll see if I get him to post some. He has built and tuned many TPI’s according to him the SD cars are much more difficult to tune than the MAF cars. I am guessing it could be that the IAC is bad. It is the original one to the car.
There are people with similar motors and they are running 50lb injectors. From what my reasearch has showed me these people get their cars to run correctly.
This is a learning process for me and I appreciate all the responses.
There are people with similar motors and they are running 50lb injectors. From what my reasearch has showed me these people get their cars to run correctly.
This is a learning process for me and I appreciate all the responses.
Yes you CAN use 50 pph injectors. I have 42 pph injectors feeding a motor making 420 RWHP That said, larger injectors means that there is more fuel per millisecond. Could make it harder tune for idle if it is too large. Beyond a certain point, it might not be good regardless of the tuner having skills or not.
I suggest you get a tuner to adjust it all over instead of simply jacking your idle up. It might be just masking a problem with the tune.
Thread Starter
Racer
Joined: May 2014
Posts: 290
Likes: 66
From: Chicago Illinois
If he were a good tuner he would NOT need to rely on the MAF to cover for his lack of ability Before I toss money on the IAC I'd get the tuner to do the chip on the dyno.
Yes you CAN use 50 pph injectors. I have 42 pph injectors feeding a motor making 420 RWHP That said, larger injectors means that there is more fuel per millisecond. Could make it harder tune for idle if it is too large. Beyond a certain point, it might not be good regardless of the tuner having skills or not.
I suggest you get a tuner to adjust it all over instead of simply jacking your idle up. It might be just masking a problem with the tune.
Yes you CAN use 50 pph injectors. I have 42 pph injectors feeding a motor making 420 RWHP That said, larger injectors means that there is more fuel per millisecond. Could make it harder tune for idle if it is too large. Beyond a certain point, it might not be good regardless of the tuner having skills or not.
I suggest you get a tuner to adjust it all over instead of simply jacking your idle up. It might be just masking a problem with the tune.
He told me that the reason he raised the idle was to "band aid' the issue. I was hoping there was a place near me to go and have it properly tuned but so far the only place that someone suggested is WBD. It's about an hour and a half away so I need to make some time to get up there.
What would be the correct size injectors? 22lb or 24lb?
Last edited by Steves LS6; Aug 22, 2018 at 12:52 PM.
Team Owner
Joined: Jul 2004
Posts: 28,424
Likes: 3,276
From: Hartford WI
He told me that the reason he raised the idle was to "band aid' the issue. I was hoping there was a place near me to go and have it properly tuned but so far the only place that someone suggested is WBD. It's about an hour and a half away so I need to make some time to get up there.
What would be the correct size injectors? 22lb or 24lb?
What would be the correct size injectors? 22lb or 24lb?
Right now you have 30 so if they are newer, I'd try to see if the tuner can make it work before buying 24. Go with what the tuner thinks he can do with what you have.