DIY PROM Do It Yourself PROM chip burning help. No PROM begging. No PROMs for sale. No commercial exchange. Not a referral service.

Just dynoed car after porting heads, Inj will not go above 7.34ms??

Thread Tools
 
Search this Thread
 
Old May 25, 2010 | 09:09 PM
  #1  
87_TA's Avatar
Thread Starter
TGO Supporter
 
Joined: Dec 2001
Posts: 2,308
Likes: 0
From: ELIZABETH,PA,USA
Just dynoed car after porting heads, Inj will not go above 7.34ms??

Well, usually very agaist dyno's but new place opened not far from house. Talked with guy who was cool and pretty cheap..
Car had been feeling sort of dissapointing since, had a conservative tune in with only 32 degrees timing.
-First pass 377 hp at 5500 - 14.5 air fuel
-Second pass added 3 lb pressure and jumped to 419 at 5600 or so. 13.8 air fuel.
-third pass added 10% to pe enrichment, jumped again to 434 at 13.5.
- 4th pass added another 15%, jumped to 451 @ 6k, 13.2 air fuel.
- 5th pass added more to PE enrichment no change at all.
- 6th pass added 4° TIMING TO 36, made 463 @ 6100
- 7th pass added another 2° to 38°, made 468 @ 6100

Pretty good on 93, hope to hit track Thursday, but weather is looking bad.

Made more than I expected, expected 450ish.. Seems that injectors refuse to open any longer than 7.34ms??? Last three changes they maxed at 7.34 and stayed there - Something with code? VE is currently at 100 and PE enrich was raised from 10° to 24° with no change in PW - and they hold steady at 7.34 after initial AE.

I also know the Miniram is now a restriction only flowing 283, I suspect with a single plane I will gain 30-40 HP and 1000 rpm.. Looking at data, I started pulling vacuum at 5000 rpm. Makes peak TQ somewhere around 4k it seems at 465 and stays very flat to 5200..
__________________
Reply
Old May 26, 2010 | 01:40 AM
  #2  
gta324's Avatar
Supreme Member
25 Year Member
 
Joined: Aug 1999
Posts: 2,441
Likes: 1
From: sweden
Car: GTA -89
Engine: Blown 415"
Transmission: 4L80E
Axle/Gears: Strange 12-bolt
Re: Just dynoed car after porting heads, Inj will not go above 7.34ms??

https://www.thirdgen.org/forums/diy-...limit-fix.html
Reply
Old May 26, 2010 | 10:43 AM
  #3  
87_TA's Avatar
Thread Starter
TGO Supporter
 
Joined: Dec 2001
Posts: 2,308
Likes: 0
From: ELIZABETH,PA,USA
Re: Just dynoed car after porting heads, Inj will not go above 7.34ms??

Thank you for link, I knew I read about this somewhere prior but could not find. I have never edited code before and need to learn. after 10 yrs of prom tuning I should by now I guess.. If I were to just decrease the inj constant it should fool the ecm to net the same result correct?

Thanks for any help.
Reply
Old May 26, 2010 | 11:23 AM
  #4  
Ronny's Avatar
TGO Supporter
20 Year Member
iTrader: (1)
 
Joined: Mar 2003
Posts: 6,880
Likes: 4
From: wisconsin
Re: Just dynoed car after porting heads, Inj will not go above 7.34ms??

What would happen if you upped fuel press?
Reply
Old May 26, 2010 | 11:33 AM
  #5  
87_TA's Avatar
Thread Starter
TGO Supporter
 
Joined: Dec 2001
Posts: 2,308
Likes: 0
From: ELIZABETH,PA,USA
Re: Just dynoed car after porting heads, Inj will not go above 7.34ms??

That would work, but I am already at 55psi and do not wish to go any higher than that unless I have to. I would likely need to up it to 62 or so the get any adjustability.
Reply
Old May 26, 2010 | 12:05 PM
  #6  
gta324's Avatar
Supreme Member
25 Year Member
 
Joined: Aug 1999
Posts: 2,441
Likes: 1
From: sweden
Car: GTA -89
Engine: Blown 415"
Transmission: 4L80E
Axle/Gears: Strange 12-bolt
Re: Just dynoed car after porting heads, Inj will not go above 7.34ms??

Make a copy of bin.

Use tunerpro go to "tools" "Advanced" "hex Editor"

Change the adresses quoted in link.

Its not hard at all, If you like you can email me the "virgin" bin and "your new one" and I can check it for you.....I could modify yours but I think you should atleast try to modify it by your self...........
Reply
Old May 26, 2010 | 12:40 PM
  #7  
Orr89RocZ's Avatar
Supreme Member
20 Year Member
Liked
Loved
Community Favorite
iTrader: (20)
 
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: Just dynoed car after porting heads, Inj will not go above 7.34ms??

Lean is mean man, 13.2 is probably making max power but it may want to be richer. I never knew there was a PW limit in 730 but I've never tuned 8D so that may be a reason why

What size injectors do you have now? Will they support much more power? Those are some very stout numbers.
Reply
Old May 26, 2010 | 12:48 PM
  #8  
RBob's Avatar
Moderator
iTrader: (1)
 
Joined: Mar 2002
Posts: 18,432
Likes: 234
From: Chasing Electrons
Car: check
Engine: check
Transmission: check
Re: Just dynoed car after porting heads, Inj will not go above 7.34ms??

Originally Posted by Orr89RocZ
Lean is mean man, 13.2 is probably making max power but it may want to be richer. I never knew there was a PW limit in 730 but I've never tuned 8D so that may be a reason why
It isn't really a PW limit per-se. It is that once the displacement value becomes large the gas law math overflows which creates an artificial PW limit. By rearranging the math this overflow is eliminated along with the upper PW limit that results.

RBob.
Reply
Old May 26, 2010 | 04:30 PM
  #9  
87_TA's Avatar
Thread Starter
TGO Supporter
 
Joined: Dec 2001
Posts: 2,308
Likes: 0
From: ELIZABETH,PA,USA
Re: Just dynoed car after porting heads, Inj will not go above 7.34ms??

Originally Posted by gta324
Make a copy of bin.

Use tunerpro go to "tools" "Advanced" "hex Editor"

Change the adresses quoted in link.

Its not hard at all, If you like you can email me the "virgin" bin and "your new one" and I can check it for you.....I could modify yours but I think you should atleast try to modify it by your self...........

Thank you very much! It is time I do this for myself, I will make change and send to you tonight. Thanks again.
Reply
Old May 26, 2010 | 04:32 PM
  #10  
87_TA's Avatar
Thread Starter
TGO Supporter
 
Joined: Dec 2001
Posts: 2,308
Likes: 0
From: ELIZABETH,PA,USA
Re: Just dynoed car after porting heads, Inj will not go above 7.34ms??

Originally Posted by Orr89RocZ
Lean is mean man, 13.2 is probably making max power but it may want to be richer. I never knew there was a PW limit in 730 but I've never tuned 8D so that may be a reason why

What size injectors do you have now? Will they support much more power? Those are some very stout numbers.

Thanks Orr, I am happy with the numbers it layed down.. It doing better than expected with Mini Ram, I would expect to pick up atleast 30 with the single plane swap..
Reply
Old May 26, 2010 | 06:13 PM
  #11  
87_TA's Avatar
Thread Starter
TGO Supporter
 
Joined: Dec 2001
Posts: 2,308
Likes: 0
From: ELIZABETH,PA,USA
Re: Just dynoed car after porting heads, Inj will not go above 7.34ms??

Originally Posted by gta324
Make a copy of bin.

Use tunerpro go to "tools" "Advanced" "hex Editor"

Change the adresses quoted in link.

Its not hard at all, If you like you can email me the "virgin" bin and "your new one" and I can check it for you.....I could modify yours but I think you should atleast try to modify it by your self...........
Message sent, it would not allow me to attach through thirdgen e mail - if you return with your mail I will send.. Thanks, I think I did it..

A question though, what does the change allow? does it allow you to place value higher than 100 in VE, or does it allow the % added with PE adder to be effective? Thanks for helping again.
Reply
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
MustangBeater20
TBI
11
Oct 29, 2022 09:20 PM
camaro71633
Tech / General Engine
39
Sep 1, 2015 10:24 AM
85Iroc-Z
Power Adders
18
Aug 13, 2015 01:58 AM
89-S-dime
TBI
4
Aug 12, 2015 11:57 AM
mx127
Electronics
2
Aug 10, 2015 08:13 AM




All times are GMT -5. The time now is 06:14 AM.