ECM Upgrade for CFI
Burning Brakes
Joined: Feb 2013
Posts: 1,173
Likes: 152
From: norway
Team Owner
Joined: Oct 2007
Posts: 26,745
Likes: 694
From: PA
mine can do 5200 rpms ported manifoil ,bored tb , koolblue filter , 1,6 rt , 14psi fuel , pressure, 12 deg.timing , lnew cat back , +++ next winther new ported heads and cam + paralell plumbing + 80 lb/hr injectors 
but it runs better than a 85 -89 modell right now
ported manifoil ,bored tb , koolblue filter , 1,6 rt , 14psi fuel , pressure, 12 deg.timing , lnew cat back , +++ next winther new ported heads and cam + paralell plumbing + 80 lb/hr injectors but it runs better than a 85 -89 modell right now 
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
YES, you CAN absolutely adjust the base timing by turning the distributor and realize significant gains from that alone. The timing is conservative everywhere, and therefore you can advance it "everywhere" w/a base timing adjustment and get a good, solid gain from it.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
That vacuum adjusted pressure regulator is an interesting idea... It is my understanding that the stock regulator is in the rear throttle body and not adjustable at all. You don't happen to have any more references for the marine one do you? Otherwise it sounds like time for more googling.
Reading...
THIRD GEN
Team Owner
Joined: Oct 2007
Posts: 26,745
Likes: 694
From: PA
If there was a smiley that was a half smile with eyes that say "Yes there is." I would have used it haha
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
If your wanting to change your ecm out to something that is "flash", the best option out there will be dynamicefi's flash ecm. You get the most bang for your buck.
I've been running that ecm for 4 years now and am very pleased with it. It allows to store up to 8 tunes at one time and is set up to allow you to expand your build at any time.
I've done lots of research in the beginning. I first did similar mods as you and used that ecm, it did also allow me to convert over to multiport when I wanted to. Now the car runs a Holley stealth ram intake. Lays down 463 ponies with a NA engine.
FWIW- 2 in TB's are useless, proven fact. Some here have tried it, and I have to.. there was no track time difference using stock size or 2 in TB's on a XRAM.. and even tho the renegade claims the 25hp gain which is nice... a properly ported intake or in my case the XRAM proved a 38hp gain.. on the dyno. Proven fact. Save your $400 and find a better place to spend it.
I've been running that ecm for 4 years now and am very pleased with it. It allows to store up to 8 tunes at one time and is set up to allow you to expand your build at any time.
I've done lots of research in the beginning. I first did similar mods as you and used that ecm, it did also allow me to convert over to multiport when I wanted to. Now the car runs a Holley stealth ram intake. Lays down 463 ponies with a NA engine.
FWIW- 2 in TB's are useless, proven fact. Some here have tried it, and I have to.. there was no track time difference using stock size or 2 in TB's on a XRAM.. and even tho the renegade claims the 25hp gain which is nice... a properly ported intake or in my case the XRAM proved a 38hp gain.. on the dyno. Proven fact. Save your $400 and find a better place to spend it.
Last edited by qws; Jul 30, 2015 at 09:20 PM.
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Thread Starter
Pro
Joined: Dec 2014
Posts: 530
Likes: 10
I didn't know the CFI would let you get away with that much mechanical change to the base timing. A lot of other EFI systems will get really pissed off if you try to set the base forward too much.
Thread Starter
Pro
Joined: Dec 2014
Posts: 530
Likes: 10
If your wanting to change your ecm out to something that is "flash", the best option out there will be dynamicefi's flash ecm. You get the most bang for your buck.
I've been running that ecm for 4 years now and am very pleased with it. It allows to store up to 8 tunes at one time and is set up to allow you to expand your build at any time.
I've been running that ecm for 4 years now and am very pleased with it. It allows to store up to 8 tunes at one time and is set up to allow you to expand your build at any time.
I've done lots of research in the beginning. I first did similar mods as you and used that ecm, it did also allow me to convert over to multiport when I wanted to. Now the car runs a Holley stealth ram intake. Lays down 463 ponies with a NA engine.
FWIW- 2 in TB's are useless, proven fact. Some here have tried it, and I have to.. there was no track time difference using stock size or 2 in TB's on a XRAM.. and even tho the renegade claims the 25hp gain which is nice... a properly ported intake or in my case the XRAM proved a 38hp gain.. on the dyno. Proven fact. Save your $400 and find a better place to spend it.
And i can certainly believe that just boring the throttle bodies without all the associated mods might not do much...
Team Owner
Joined: Oct 2007
Posts: 26,745
Likes: 694
From: PA
Just have fun with your car. I am going tk check the timing on mine. I have had two of them so far and never had an issue with how they ran. Slow? In stock form, yes. Lol but in my opinion they are all slow so I don't get hung up on it too much.
I prefer a C4 over the other years because I grew up with them.
Team Owner
Joined: Oct 2007
Posts: 26,745
Likes: 694
From: PA
2. Throw some decent SBC heads on it - $1,000
3. Headers - $500
4. Custom exhaust - $500 (at about any shop this is the most it should cost)
5. Nice little cam that works with the stock computer - $250
Say for all gaskets and seals and timing chain and getting your TB's done (if you can't do it) and fluid - $500
That's under 3k and some wrench time. You will have way more than 250 hp and be quite streetable as long as you don't go wacky on the compression and cam. Just exhaust and porting your intake would get you to about 250 hp. So for not a lot of money you can get to your goal. That would be what, a grand or a little more?
Melting Slicks
Joined: Jan 2005
Posts: 2,658
Likes: 4
From: Clifton Park NY
In my honest opinion and with your mods. I wouldn't do an ecm change. Its not worth it. I've been there... done that. Listen to the information Tom has told you, he is absolutely correct.
I didn't need the ecm until I went to the 90lb injectors.
If I had to do it all over again I would have done my mods differently knowing what I do now.
I did knock my track time down almost 2 full seconds.
My suggestion.... do your few mods, adjust your fuel pressure, adjust timing and leave it. Enjoy the car..
I didn't need the ecm until I went to the 90lb injectors.
If I had to do it all over again I would have done my mods differently knowing what I do now.
I did knock my track time down almost 2 full seconds.
My suggestion.... do your few mods, adjust your fuel pressure, adjust timing and leave it. Enjoy the car..
Thread Starter
Pro
Joined: Dec 2014
Posts: 530
Likes: 10
I'm planning on doing this, but if it turns out to be too much work I may get impatient and just order a Renegade.
I'm looking at a pair of Scorpion aluminum heads with 64cc chambers, 180cc intake ports, 2.02" intake/1.6" exhaust valves. They come assembled valves, springs and screw in studs, guide plates, etc. With the dish top pistons in the L83 this should give a static compression ratio somewhere between 9.5:1 and 10:1.
Headers are on the plan.
The car already has a decent cat back system I'll splice into.
I was planning on using the Comp Cams XE280H retrofit hydraulic roller cam with link-bar roller lifters, Comp Cams pushrods and a set of 1.6 ratio roller rockers... I was thinking about the Ultra Magnums, but I may go with Scorpions.
Fel-Pro
Comp Cams Magnum double roller is what I had in mind
The cam I picked should be streetable and it along the heads should work O.K. on 93 octane pump gas. There is a place in Houston that I can take an extra set of throttle bodies I have in order to have them rebuilt, bored and bushings installed.
I'm not going to do it half way, I'm going to do it all at once. Realistically I'm figuring on a $2500-$3000-ish parts budget. I've already got way more into this car fixing up the interior and stuff than its worth so what the hell.
2. Throw some decent SBC heads on it - $1,000
3. Headers - $500
4. Custom exhaust - $500 (at about any shop this is the most it should cost)
5. Nice little cam that works with the stock computer - $250
Say for all gaskets and seals
and timing chain
and getting your TB's done (if you can't do it) and fluid - $500
That's under 3k and some wrench time. You will have way more than 250 hp and be quite streetable as long as you don't go wacky on the compression and cam.
That's under 3k and some wrench time. You will have way more than 250 hp and be quite streetable as long as you don't go wacky on the compression and cam.
Just exhaust and porting your intake would get you to about 250 hp. So for not a lot of money you can get to your goal. That would be what, a grand or a little more?
Last edited by softwarejanitor; Jul 31, 2015 at 11:10 PM.
Thread Starter
Pro
Joined: Dec 2014
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So maybe what I'm looking at will get me closer to 290 HP, but if it doesn't and I only get to 250 HP I will still be happy.
The 290 is based on adding the "up to" numbers... which as I said, I know not to be completely realistic... 205 stock + 20 for intake porting & TB boring & upgraded injectors + 20 for headers and exhaust + 20 for heads + 20 for cam and maybe + another 5 for roller rockers and double roller timing set...
290 would be good... competitive with a lot of lightly modded L98 cars and wouldn't get completely crushed by LT1 cars...
Thread Starter
Pro
Joined: Dec 2014
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Not any measureable amount, but the 1.5 ratio roller rockers do, and there is no point putting in a roller cam, lifters and rockers and putting in a stock timing set..
A lot of people really don't get anywhere near the power they think they are going to get from mods. I'd rather be pessimistic and pleasantly surprised than optimistic and disappointed if I take this thing to a "dyno days" event or something.
If you can't get over 300 hp with $2,500 there is major issue.
Team Owner
Joined: Aug 2004
Posts: 21,543
Likes: 3,216
From: Park City Utah
I only say that (in this thread and others) so that when you get it done, and you dyno 250hp (if that were to happen), then that would be a huge indicator that you have more work to do.
Dominic Sorresso on this forum did the same build you're doing, basically, except that he extrude honed his intake, rather than porting it, so IMO, he left some on the table there by not removing enough material. Anyway, his results were ~320hp, if I recall correctly. That should be your benchmark, IMO, for the money you're spending and the parts you plan on installing.
2nd Gear
Joined: Nov 2015
Posts: 2
Likes: 0
If I'm not mistaken, a motor is nothing more than an air pump. Put it in and put it out.
I'm old school, I ran a tunnel ram dual carb on the street in the 70's. Holley set my engine up with dual 480's they claimed it was better to run lean than rich. They physically touched my motor because I was running 650's, and they were in town at my parts house.
Bought a crossfire, the 1st thing I'm doing is y'ing the tbi's for 14lbs parallel. 2nd thing is replacing the manifold. 3rd is going to a 1:6 rocker arm.
The question is Why can not the ECM handle anything further? Too Slow?
I'm old school, I ran a tunnel ram dual carb on the street in the 70's. Holley set my engine up with dual 480's they claimed it was better to run lean than rich. They physically touched my motor because I was running 650's, and they were in town at my parts house.
Bought a crossfire, the 1st thing I'm doing is y'ing the tbi's for 14lbs parallel. 2nd thing is replacing the manifold. 3rd is going to a 1:6 rocker arm.
The question is Why can not the ECM handle anything further? Too Slow?
Last edited by thealaskan63; Nov 13, 2015 at 08:31 AM. Reason: duplicat