So I got the 383 HSR dyno'd. Good and Bad inside
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
i'm trying to move things along yes
Gotta get this car fast
Gotta get this car fast Supreme Member
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From: Winston salem, NC
Car: 1987 1SICIROC.....1999 TransAm
Engine: 385 HSR.....LS1
Transmission: 700R4 with Midwest 3400 2.4str...M6
Axle/Gears: SLP Zexel Posi unit 3.42's...3.73's
Re: So I got the 383 HSR dyno'd. Good and Bad inside
hey yo!.......have you wieghed your car with you in it? I went by a dump today and got on their scales and weighed in at 3411 with me in and a 1/4 tank of gas. Ofcourse that wasnt with a full NX bottle in the back either and I think the bottle full comes out to about 27lbs.
Im just curious as to what your race weigh.
Im just curious as to what your race weigh.
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Car: 89 GTA
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Re: So I got the 383 HSR dyno'd. Good and Bad inside
Looks good can't wait to see if there is any improvement at the track
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
i weighed it last year at 3400 with 1/2 tank without me in it. add race slicks/wheels and drop gas to less than 1/4 tank on raceday, its about 3450 or so with me in it.
now with aluminum heads/waterpump/ministarter/etc i have no idea what it weighs. I'm thinking somewhere in the 3400-3450 range
with me in it.
now with aluminum heads/waterpump/ministarter/etc i have no idea what it weighs. I'm thinking somewhere in the 3400-3450 range
with me in it. Supreme Member
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From: Mims, Florida
Car: '87 IROCZ
Engine: 395 ZZ4
Transmission: ProBuilt 700R4
Axle/Gears: 9 bolt 3.70s
Re: So I got the 383 HSR dyno'd. Good and Bad inside
FWIW: I have determined that my MEGA MAF (3.5" OD aluminum tube) will flow about 908 CFM. This is based on 3rd gen and 4th gen MAF flow data and TBs flow measurements. Thats a big improvement over the 658CFM that I have the the screenless factory MAF.
Orr: now you got to burn a chip for your large MAF.
Orr: now you got to burn a chip for your large MAF.
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From: NYC / Jersey
Car: 1990 Trans Am GTA
Engine: Turbo 305 w/MS2
Transmission: 700R4
Re: So I got the 383 HSR dyno'd. Good and Bad inside
Originally Posted by Orr89RocZ
....
Last edited by Street Lethal; Aug 13, 2008 at 03:07 PM.
Thread Starter
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
am considering the possibility this may not work and lsx 85+mm TB and converter will be needed. not sure how the converter works but the one i did find seems to work well just is expensive
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
There she be. Final setup. i had to clearance more bracing on the hood to clear it but it clears fine now.
Problems.
At first the car didnt start, then it fired and quickly died, no matter if i held pedal down or not. Probly lean so ok lets play with the scalars on the table...try to get this thing running.
made some changes little by little and car started staying alive longer but still dying
finally got the car to idle but its going alittle lean so i still need to tweak the tables, other tables tho are not good at all, goes very lean with just alittle bit of throttle
Heres the funny thing, i increased the HELL out of the scalars. i'm up from like 16 with my old chip in table 1, all the way to 1C i think it is now. like a increase of 6. I'm up from 30 in table 2 to 3A now and its still not good.
i really didnt expect this much of a increase but wideband is showing happier the more i go up so i'll play with it agian tomorrow.
GOOD THINGS:
this must flow a TON of air just based on how much i have to change the scalars. at idle and give it some part throttle it sounds like a turbo spooling its sucking in air! its loud! So awesome...this should open up this car for sure
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From: Cypress, California
Car: 1989 GTA
Engine: 369 TPI
Transmission: 4L60E
Axle/Gears: 3.70 Nine Bolt
Re: So I got the 383 HSR dyno'd. Good and Bad inside
Hehehehe. Looks like room for a bigger air filter in the future.
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Re: So I got the 383 HSR dyno'd. Good and Bad inside
One thing to keep in mind is that sensor was designed for the element to be in the middle of the flowpath, and now you are not... so way more air is going in than you are metering. Flipping the MAF over (I know it wont look as good) might help some.
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From: Mims, Florida
Car: '87 IROCZ
Engine: 395 ZZ4
Transmission: ProBuilt 700R4
Axle/Gears: 9 bolt 3.70s
Re: So I got the 383 HSR dyno'd. Good and Bad inside
I calculated that my MEGA MAF flows about 38% more air, air that the sensor can not measure properly. Therefore, I figured that a good starting point is to increase the scalars of each MAF table by 38%. Of coarse, the scalar for table 5 & table 6 are FF. My car started right up and ran great. I ended up making about a 2 psi change to the fuel pressure. The BLMs are all near 128 +- 4. The drivibility is very good and the car launches very hard at the dragstrip.
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
i may start over and just multiply all the values by 1.5 or basically 50% to see if that helps.
right now the sensor is tilted, its not at the base of the sensor, its off center thats for sure. Sits about 7-8 oclock right now if 6 is bottom and 12 is top of the pipe. It may not be perfectly in the middle but its pretty close.
https://www.thirdgen.org/forums/atta...mafsensor2.jpg
right now the sensor is tilted, its not at the base of the sensor, its off center thats for sure. Sits about 7-8 oclock right now if 6 is bottom and 12 is top of the pipe. It may not be perfectly in the middle but its pretty close.
https://www.thirdgen.org/forums/atta...mafsensor2.jpg
Last edited by Orr89RocZ; Aug 14, 2008 at 06:18 AM.
Thread Starter
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
jeez! i'm getting closer but still alittle off
WOT is gone
i increased scalars more and more and more and finally air fuels are getting much better but still have some lean and rich spots so i'll have to fine tune it more this weekend.
WOT now is 16 to 1 AFR so thats how much more air i'm getting into this thing!! i know the upper MAF tables arent there yet but usually by 4500-5000 the MAF is maxed out anyway and PE mode takes over. I'm still lean now considering that. i expect big power increases with this intake once i get it fine tuned. I hope to have tune well inorder for wednesday next week so i can get new times
WOT is gone
i increased scalars more and more and more and finally air fuels are getting much better but still have some lean and rich spots so i'll have to fine tune it more this weekend. WOT now is 16 to 1 AFR so thats how much more air i'm getting into this thing!! i know the upper MAF tables arent there yet but usually by 4500-5000 the MAF is maxed out anyway and PE mode takes over. I'm still lean now considering that. i expect big power increases with this intake once i get it fine tuned. I hope to have tune well inorder for wednesday next week so i can get new times
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From: Cypress, California
Car: 1989 GTA
Engine: 369 TPI
Transmission: 4L60E
Axle/Gears: 3.70 Nine Bolt
Re: So I got the 383 HSR dyno'd. Good and Bad inside
Good. You have eliminated two intake restrictions and the last remains to be seen as to how much. The last being the air filter. Hard for me to tell in the pictures as to how big it is. Definitely an improvement over stock and maybe big enough. Heck you might pick up 20 horsepower.
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
i hope to break 120 at the 1/4 wednesday
that would be awesome!
that would be awesome! Member
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From: Brandon Mississippi
Car: 1989 Camaro
Engine: 383
Transmission: 700R4
Axle/Gears: 3.73
Re: So I got the 383 HSR dyno'd. Good and Bad inside
I think you can do it, just keep tuning. I didn't get to take mine to the track this week because of rain. I wish I had a 1/4 mile track instead of this 1/8 crap.
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From: Pittsburgh PA
Car: 89 Iroc-z
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Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
i can only imagine a 4" MAF being even more difficult to tune than this 3.5" .
how much did you scale the scalars? or did you cut injector constant down to?
how much did you scale the scalars? or did you cut injector constant down to?
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From: Brandon Mississippi
Car: 1989 Camaro
Engine: 383
Transmission: 700R4
Axle/Gears: 3.73
Re: So I got the 383 HSR dyno'd. Good and Bad inside
I left the injectors set at 30 where they belong. I ended up with the first scalar set to 20. Can't remember the rest off hand.
I had intentions of taking some pictures of the 4" and posting them but I have been working my tail off on a 2002 Mustang GT engine.
About a month ago this guy called me up and said he has stripped a spark plug hole out in his 4.6 and wanted to know what it would take to fix it. I gave him a $350 price to pull the head and do it right but a buddy of his had told him you could fix it while still on the car and save $$$. I refused to retread the hole and put an insert in while on the car and explained why.
Needless to say they did it anyway and ended up with metal on top of the pistons which in turn got ontop of 3 other pistons and now he gets to pay me to rebuild it. He was sick when I gave him that price.
I had intentions of taking some pictures of the 4" and posting them but I have been working my tail off on a 2002 Mustang GT engine.
About a month ago this guy called me up and said he has stripped a spark plug hole out in his 4.6 and wanted to know what it would take to fix it. I gave him a $350 price to pull the head and do it right but a buddy of his had told him you could fix it while still on the car and save $$$. I refused to retread the hole and put an insert in while on the car and explained why.
Needless to say they did it anyway and ended up with metal on top of the pistons which in turn got ontop of 3 other pistons and now he gets to pay me to rebuild it. He was sick when I gave him that price.
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From: chi, Illinois
Car: Pontiac T/A
Engine: 305
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Axle/Gears: Borg Warner 9-Bolt w/ 2.77 gears.
Re: So I got the 383 HSR dyno'd. Good and Bad inside
That's what he gets for not doing it the right way. Some guys are always trying to cut corners.
Joined: Apr 2002
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From: Midland, GA
Car: 91' Z28, 92' Z28
Engine: 383, L98 stock
Transmission: Built 700R4, Stock 700R4
Axle/Gears: 12 Bolt 3.73, 10 Bolt 3.23
Re: So I got the 383 HSR dyno'd. Good and Bad inside
Looking good man! Making MAF work.
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
eh hopefully i can show the speed density bandwagon that there are other ways
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From: Brandon Mississippi
Car: 1989 Camaro
Engine: 383
Transmission: 700R4
Axle/Gears: 3.73
Re: So I got the 383 HSR dyno'd. Good and Bad inside
If SD is the way to go why does all the new cars have MAF?
Why do so many worry about the ECM only seeing 255 grams/sec?
The first time I built a performance fuel injected engine I didn't know you could tune the way we do, I did know you could mail order a chip. but my friends kept telling me to stay away from FI casue you can't make it run like they do the carb engines, but I built a nice TPI engine anyway. When I found this site and start researching all I see was change from MAF to SD to do away with the MAF restriction. MY MAF IS HERE TO STAY!
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Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
well i played with the upper tables today and air fuel is back near 13.8-14.0 to 1 at WOT in the 5000-5700 range. THats about where it was before so maybe i didnt gain much with this intake?
hard to tell since i really changed the MAF tables alot to get air fuel back to where i wanted it. I will see if i gained much this wednesday hopefully. suppose to be a nice day, 60's temps at night but mid high 70's during the evening at race time. i'll improve from the better weather but i hope to really improve from this MAF and intake
hard to tell since i really changed the MAF tables alot to get air fuel back to where i wanted it. I will see if i gained much this wednesday hopefully. suppose to be a nice day, 60's temps at night but mid high 70's during the evening at race time. i'll improve from the better weather but i hope to really improve from this MAF and intake
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From: Mims, Florida
Car: '87 IROCZ
Engine: 395 ZZ4
Transmission: ProBuilt 700R4
Axle/Gears: 9 bolt 3.70s
Re: So I got the 383 HSR dyno'd. Good and Bad inside
I could have offered this up some time ago. In order for my 3.5" MAF to get the same BLMs while driving around as the factory MAF had, I had to use the following MAF table scalars: 1F, 40, 6F, B4, FF, and FF. Using these scalars, I was able to keep the BLMs close to 128 for drivibility. These scalars kept me close to 14.7:1. BTW: The factory MAF scalars were 17, 30, 53, 87, CF, and FF. As Orr stated, the MAF is overwelmed at about 5,000RPM. That is where the PE table takes over (more fuel VS RPM). These 3.5" MAFs flow a bit more than 900 CFM; should be plenty for a small block stroker that is normally aspirated.
Something else was touched on above. The best system is a MAF & MAP system. The MAF is not good sudden throotle openings, while the MAP does not measure the air flow, it takes a stab at it while knowing the engine RPM and the incoming air temperature. When the programming is done correctly, the MAF/MAP system is very robust. However, the MAF/MAP system in my SS is all MAF above 4,000RPM.
Something else was touched on above. The best system is a MAF & MAP system. The MAF is not good sudden throotle openings, while the MAP does not measure the air flow, it takes a stab at it while knowing the engine RPM and the incoming air temperature. When the programming is done correctly, the MAF/MAP system is very robust. However, the MAF/MAP system in my SS is all MAF above 4,000RPM.
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
alot of LSX guys go MAF-less tunes however. i dont have final values for my scalars but table 1 is 22 or 23 now but i went into the table and lowered a few to get idle down.
its pretty sensitive at idle. a gram or two change really alters fuel ratios. idle is around 14-14.2 to 1 but i have a lean condition just off idle all the way to around 37 grams/sec. i had it way rich at 12.x to 1 but i changed it to lean this time around so i'll have to dial in. for the most part its close all around now
Just so hard trying to hit those high MAF flows on public roads with this car
a problem i do notice is after a while of driving, the metal pipes really suck up heat so i may loose more power the hotter it gets over the plastic intake. but once its cooled down, it should haul ***
its pretty sensitive at idle. a gram or two change really alters fuel ratios. idle is around 14-14.2 to 1 but i have a lean condition just off idle all the way to around 37 grams/sec. i had it way rich at 12.x to 1 but i changed it to lean this time around so i'll have to dial in. for the most part its close all around now
Just so hard trying to hit those high MAF flows on public roads with this car

a problem i do notice is after a while of driving, the metal pipes really suck up heat so i may loose more power the hotter it gets over the plastic intake. but once its cooled down, it should haul ***
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From: GA
Car: '90 C1500
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Re: So I got the 383 HSR dyno'd. Good and Bad inside
alot of LSX guys go MAF-less tunes however. i dont have final values for my scalars but table 1 is 22 or 23 now but i went into the table and lowered a few to get idle down.
its pretty sensitive at idle. a gram or two change really alters fuel ratios. idle is around 14-14.2 to 1 but i have a lean condition just off idle all the way to around 37 grams/sec. i had it way rich at 12.x to 1 but i changed it to lean this time around so i'll have to dial in. for the most part its close all around now
Just so hard trying to hit those high MAF flows on public roads with this car
a problem i do notice is after a while of driving, the metal pipes really suck up heat so i may loose more power the hotter it gets over the plastic intake. but once its cooled down, it should haul ***
its pretty sensitive at idle. a gram or two change really alters fuel ratios. idle is around 14-14.2 to 1 but i have a lean condition just off idle all the way to around 37 grams/sec. i had it way rich at 12.x to 1 but i changed it to lean this time around so i'll have to dial in. for the most part its close all around now
Just so hard trying to hit those high MAF flows on public roads with this car

a problem i do notice is after a while of driving, the metal pipes really suck up heat so i may loose more power the hotter it gets over the plastic intake. but once its cooled down, it should haul ***
Also, about the heat...the air moves through the tube too fast to get any of the heat so....I wouldn't worry about it too much. If you do, just ceramic coat it and that will take care of it.
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
i'm not to concerned since at the track i'll ice it all down and it will not be hot when i run with all the rest the car will see between rounds if its crowded at the track. last time out it wasnt and i raced rounds in about 40 min intervals. thats pretty good for our track
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Joined: Mar 2004
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From: Brandon Mississippi
Car: 1989 Camaro
Engine: 383
Transmission: 700R4
Axle/Gears: 3.73
Re: So I got the 383 HSR dyno'd. Good and Bad inside
I the road I work on is a dead end with us at the end. When I turned off the hiway I slowed to near a stop and just nailed it. I did have it datalogging so I could see what its doing at wot.
I still have some tuning to do in the high rpms cause it never went over 210 grams and that was at 6250 rpms with a 8.56 on the w-b. This was all at wot.
I have yet to change anything in the pe vs rms table but I noticed that from 3600 up is set to -7.82
Oh well, I knew I needed wot tuning so here we go.
I still have some tuning to do in the high rpms cause it never went over 210 grams and that was at 6250 rpms with a 8.56 on the w-b. This was all at wot.
I have yet to change anything in the pe vs rms table but I noticed that from 3600 up is set to -7.82
Oh well, I knew I needed wot tuning so here we go.
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From: Wisconsin
Car: 79 Monte Carlo
Engine: 406
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Axle/Gears: Phord 9 inch/3.90
Re: So I got the 383 HSR dyno'd. Good and Bad inside
Orr,
Very nice results on the project overall. I took a look at the pictures in your signature and had a question for you. How extensive was the porting to your Stealth Ram? It looks to have had the typical contouring of the runners on top of the intake, but my real question is if actual material was removed from the runners themselves. I can see the finish was altered in the runners, just curious if it was "deep" enough to reshape or remove material. Was the plenum modified also?
I ask because I've been researching the "best" alternative to the carb on my car. With the current hydraulic roller 406 built for torque, the car has gone a best of 11.59 @ 113.85, and my goal with EFI is not to gain power, just not lose much.
Your thoughts would be greatly appreciated.
Very nice results on the project overall. I took a look at the pictures in your signature and had a question for you. How extensive was the porting to your Stealth Ram? It looks to have had the typical contouring of the runners on top of the intake, but my real question is if actual material was removed from the runners themselves. I can see the finish was altered in the runners, just curious if it was "deep" enough to reshape or remove material. Was the plenum modified also?
I ask because I've been researching the "best" alternative to the carb on my car. With the current hydraulic roller 406 built for torque, the car has gone a best of 11.59 @ 113.85, and my goal with EFI is not to gain power, just not lose much.

Your thoughts would be greatly appreciated.
Last edited by DFI79MC; Aug 17, 2008 at 08:56 AM.
Joined: Jul 1999
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From: Orange, SoCal
Car: 1990 Pontiac Trans Am
Engine: 355 TPI siamesed runners
Transmission: Tremec T56
Axle/Gears: 12-Bolt 3.73
Re: So I got the 383 HSR dyno'd. Good and Bad inside
I'm with you on that one.
If SD is the way to go why does all the new cars have MAF?
Why do so many worry about the ECM only seeing 255 grams/sec?
The first time I built a performance fuel injected engine I didn't know you could tune the way we do, I did know you could mail order a chip. but my friends kept telling me to stay away from FI casue you can't make it run like they do the carb engines, but I built a nice TPI engine anyway. When I found this site and start researching all I see was change from MAF to SD to do away with the MAF restriction. MY MAF IS HERE TO STAY!
If SD is the way to go why does all the new cars have MAF?
Why do so many worry about the ECM only seeing 255 grams/sec?
The first time I built a performance fuel injected engine I didn't know you could tune the way we do, I did know you could mail order a chip. but my friends kept telling me to stay away from FI casue you can't make it run like they do the carb engines, but I built a nice TPI engine anyway. When I found this site and start researching all I see was change from MAF to SD to do away with the MAF restriction. MY MAF IS HERE TO STAY!
Therefore, thirdgen SD is better than thirdgen MAF. However, 4th gen MAF is better than thirdgen SD. Newer cars have MAF sensors because that allows the computer to make better fuel calculations to give better gas mileage and lower emissions.
Thread Starter
Joined: Sep 2003
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
Orr,
Very nice results on the project overall. I took a look at the pictures in your signature and had a question for you. How extensive was the porting to your Stealth Ram? It looks to have had the typical contouring of the runners on top of the intake, but my real question is if actual material was removed from the runners themselves. I can see the finish was altered in the runners, just curious if it was "deep" enough to reshape or remove material. Was the plenum modified also?
I ask because I've been researching the "best" alternative to the carb on my car. With the current hydraulic roller 406 built for torque, the car has gone a best of 11.59 @ 113.85, and my goal with EFI is not to gain power, just not lose much.
Your thoughts would be greatly appreciated.
Very nice results on the project overall. I took a look at the pictures in your signature and had a question for you. How extensive was the porting to your Stealth Ram? It looks to have had the typical contouring of the runners on top of the intake, but my real question is if actual material was removed from the runners themselves. I can see the finish was altered in the runners, just curious if it was "deep" enough to reshape or remove material. Was the plenum modified also?
I ask because I've been researching the "best" alternative to the carb on my car. With the current hydraulic roller 406 built for torque, the car has gone a best of 11.59 @ 113.85, and my goal with EFI is not to gain power, just not lose much.

Your thoughts would be greatly appreciated.
Then i went into the runners at the head port to better match my AFR head ports. opened them up alittle and carried that the whole way up into the runner path to the plenum the best i could. I used a wrench i had as a template, it was a fixed width and i ran it up and down the port to see where the tight spots were. i made all runners easily pass that wrench thru the port.
I then focused on the 4 odd bent runners the HSR has. 4 runners go straight down to the head ports, while the other 4 have a longer bend since they dont quite go straight down to the ports. At that point its thinner in cross section width than the 4 straight runner tubes. So i opened up that curve/bend taking material off the inner shortside wall. Basically made that radius straighter and also opened up the far side about an inch down from the top of the base manifold where the plenum bolts to.
I took some material out yes...but i dont consider it a extensive port job. it was a rough quick job too, i didnt even polish it with the lighter grit sand paper rolls. I think it helped tho over stock but how much so i cant say. I dont think a box stock HSR will hurt your motor tho
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From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
Hoping i picked up power with this intake mod, i dont think i really did.
DA was 2300 ft or so, better than previous 2800-3000 ft runs in hot air. cooler tonight
Car is again rough street tuned with new MAF and CAI. i think i got it close but the car just matched best ET with new trap speeds with worse 60 foot since i walked it off the line by accident
11.53 again but at 119.11 mph. 1/8 mile was slower 7.39 compared to 7.35 pervious best. mph was up at 94.22 instead of 93.3
1.66 baby 60 foot. 1.59 was previous
i contribute the gains to the weather tho. i almost hit 119 before with stock MAF. Oh well
I did however get a 1.55 60 foot and was on my way to a possible 11.4x pass when i had a wire connection come apart that killed my timing at the 1/8 mile then again at 1000 ft. car came on and off. still ran 11.6 at 116
Air fuel is possibly a touch lean still so i'm hoping to get it back on the dyno to see whats up. I expected 11.4's at 120-121 tonight. Just not gonna happen i think but i didnt watch teh gauge so i didnt get to see what its doing
DA was 2300 ft or so, better than previous 2800-3000 ft runs in hot air. cooler tonight
Car is again rough street tuned with new MAF and CAI. i think i got it close but the car just matched best ET with new trap speeds with worse 60 foot since i walked it off the line by accident

11.53 again but at 119.11 mph. 1/8 mile was slower 7.39 compared to 7.35 pervious best. mph was up at 94.22 instead of 93.3
1.66 baby 60 foot. 1.59 was previous
i contribute the gains to the weather tho. i almost hit 119 before with stock MAF. Oh well
I did however get a 1.55 60 foot and was on my way to a possible 11.4x pass when i had a wire connection come apart that killed my timing at the 1/8 mile then again at 1000 ft. car came on and off. still ran 11.6 at 116

Air fuel is possibly a touch lean still so i'm hoping to get it back on the dyno to see whats up. I expected 11.4's at 120-121 tonight. Just not gonna happen i think but i didnt watch teh gauge so i didnt get to see what its doing
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Joined: Sep 2003
Posts: 6,859
Likes: 14
From: Cypress, California
Car: 1989 GTA
Engine: 369 TPI
Transmission: 4L60E
Axle/Gears: 3.70 Nine Bolt
Re: So I got the 383 HSR dyno'd. Good and Bad inside
A dyno tune will let you see where you are at. You did a lot of modifying to the tables and more fine tuning may be in order. I would have expected your car to pick up 10 to 15 horsepower.
Well at least you know you have a solid 11.5 second car. I believe solid 11.4's are within reach.
Well at least you know you have a solid 11.5 second car. I believe solid 11.4's are within reach.
Member
Joined: Mar 2004
Posts: 472
Likes: 1
From: Brandon Mississippi
Car: 1989 Camaro
Engine: 383
Transmission: 700R4
Axle/Gears: 3.73
Re: So I got the 383 HSR dyno'd. Good and Bad inside
My wot was lean after the 4" maf was added, even after getting part throttle back tuned in. The first time I recored a wot run I was at 13.6 afr. I still havn't had a chance to get to the track or really do any tuning on mine, darn rain keeps messing me up..
Keep on tuning, you will get it there.
Keep on tuning, you will get it there.
Thread Starter
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
yeah i'm thinking it is a tad lean. i know its close to mid high 13's to 1 in the mid range up near 5000 rpm. I'll have to work on it more. There maybe a lean or rich spot here and there i have to work out.
my last two runs i added 4-5% fuel in the PE tables pretty much everwhere above 4000. it seemed to help 1/8 mile alittle, but hard to tell since the air got better
my last two runs i added 4-5% fuel in the PE tables pretty much everwhere above 4000. it seemed to help 1/8 mile alittle, but hard to tell since the air got better
Re: So I got the 383 HSR dyno'd. Good and Bad inside
Damn I'm jealous... last night you were racing and I was sitting on the couch watching the news. (Damn tropical storm)
I'm impressed your 10 bolt is still taking a beating. A few weekends ago I sheared two teeth off my pinion on the street. I had some spare parts and was able to put it back together, but now I'm worried about making a pass at the track and getting the car home in one piece. Might be time for a trailer until I can afford a 12 bolt.
If we get some good air this winter, (-600 or so DA), I think you've got 11.00's or quicker in the bag. Do you have any plans to add a roll bar? That's the other thing holding me back, the track gave me crap after my 11.48 pass. I'd hate to go back out with new tires and only get one pass. I'll be pulling my interior out in about a month to install a Wolfe 5 point.
I'm impressed your 10 bolt is still taking a beating. A few weekends ago I sheared two teeth off my pinion on the street. I had some spare parts and was able to put it back together, but now I'm worried about making a pass at the track and getting the car home in one piece. Might be time for a trailer until I can afford a 12 bolt.

If we get some good air this winter, (-600 or so DA), I think you've got 11.00's or quicker in the bag. Do you have any plans to add a roll bar? That's the other thing holding me back, the track gave me crap after my 11.48 pass. I'd hate to go back out with new tires and only get one pass. I'll be pulling my interior out in about a month to install a Wolfe 5 point.
Member
Joined: Mar 2004
Posts: 472
Likes: 1
From: Brandon Mississippi
Car: 1989 Camaro
Engine: 383
Transmission: 700R4
Axle/Gears: 3.73
Re: So I got the 383 HSR dyno'd. Good and Bad inside
At least he has an automatic transmission, I'm waiting on my 5 speed to explode. Every time I dump the clutch I just know this will be it.
I feel ya about the weather, our local track runs on Tuesday night and I work every other Tuesday night. Every time I plan to go run it rains. Its driving me nuts
Thread Starter
Joined: Sep 2003
Posts: 25,895
Likes: 429
From: Pittsburgh PA
Car: 89 Iroc-z
Engine: 555 BBC Turbo
Transmission: TH400
Axle/Gears: MWC 9” 3.00
Re: So I got the 383 HSR dyno'd. Good and Bad inside
roll bar will be coming but i gotta get this car to run faster than 11.5's! it will easily go 11.4's all day if i could hook at 100% throttle. I only get high 1.5 60's at best but i should be doing high 1.4's.
car needs more suspension tweaks and possibly more tire. More gear would help too.
car needs more suspension tweaks and possibly more tire. More gear would help too.
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iTrader: (8)
Joined: Dec 2004
Posts: 1,153
Likes: 0
From: kissimmee fl
Car: 88 iroc-z z-28
Engine: 383
Transmission: th400
Axle/Gears: 3.42
Re: So I got the 383 HSR dyno'd. Good and Bad inside
i really need to take mine to the dyno. I trapped 114 on a crooked rear end.
Autos kill hp. but its cool when you are at the track
Autos kill hp. but its cool when you are at the track
Re: So I got the 383 HSR dyno'd. Good and Bad inside
LOL I'd love to be doing ONLY mid to high 1.5's right now. My recent best pass was on a weak 1.729 60' time.
That's barely better than what my car did with 150 less RWHP and a lot less suspension. I've added more tire and done some shock/strut adjustments. It works OK on the street, but haven't gotten a chance to try it at the track due to our crappy FL weather.
By all means... I "should" be at least going 1.5 60 foots and running 11 teens or faster in the heat. But, I only have two passes on my new set up. Growing pains, right?
That's barely better than what my car did with 150 less RWHP and a lot less suspension. I've added more tire and done some shock/strut adjustments. It works OK on the street, but haven't gotten a chance to try it at the track due to our crappy FL weather.
By all means... I "should" be at least going 1.5 60 foots and running 11 teens or faster in the heat. But, I only have two passes on my new set up. Growing pains, right?
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