Cams & computer compatibility
Thread Starter
Racer
Joined: Jul 2007
Posts: 462
Likes: 21
From: Kansas City Missouri
Cams & computer compatibility
I have a guy working on getting my 86 running. It has ported slp runners, ported stock base, ported plenum, TFS-30300001 heads with the lt4 springs, and more. We put the sum-1065 cam in, which is different than what they have online now. my specs are 216/216 duration at 050. The mechanic is concerned that online it states that this cam is not computer compatible. He says, "This normally means that you have to modify either the fuel mapping or the spark mapping or both." Is this true? What exactly would that mean? I knew that I would have to eventually get a new chip, but everyone seems to think that the car should run fine until then. What should I tell this guy about this?
Thanks for the continued help and advice.
Thanks for the continued help and advice.
Race Director
Joined: Sep 2003
Posts: 16,838
Likes: 341
From: Database Error Indiana
It may run ok but you will need the chip programmed for best results. May not idle too good. I'd do a tune to get the best performance anyway. First thing you need when its running is to datalog. That will tell you what it needs.
Thread Starter
Racer
Joined: Jul 2007
Posts: 462
Likes: 21
From: Kansas City Missouri
Fuel mapping and spark mapping are both accomplished through a new tune, right? So not to be computer compatible, does that mean that the computer just won't adjust for it, which would require a new tune to basically manually tune for it? Is that all this is saying?
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Yes.
Your OEM tune will not be compatable with your mods.
It may run and maybe run a bit better. But a tune is necessary to extract all the power.
Toughest part for the 86 ECM is the EPROM needs to be flashed to change the tune.
Do not reflash your factory prom. You'll need that as a fall back in an emergency.
Contact PCMforless and have them send you a replacement eprom with the new tune.
Good Luck
Your OEM tune will not be compatable with your mods.
It may run and maybe run a bit better. But a tune is necessary to extract all the power.
Toughest part for the 86 ECM is the EPROM needs to be flashed to change the tune.
Do not reflash your factory prom. You'll need that as a fall back in an emergency.
Contact PCMforless and have them send you a replacement eprom with the new tune.
Good Luck
Melting Slicks
Joined: Mar 2008
Posts: 2,141
Likes: 76
From: Santa Maria, CA
Yes. Your mechanic is spot on that fuel and spark maps may need to be modified. But as mentioned, you won't know without logging some data to point you to where the modifications need to be made. Data logging is inexpensive. It requires a cable to connect your diagnostic port to a laptop computer and the software. You can download free software. The cable runs about $65.
Pro
Joined: Jul 2002
Posts: 703
Likes: 0
From: Milwaukee Wi
They mean it is not plug and play. It may require a "corrected" .bin. to run at 100%. If you want peak performance it needs a tune. If you accept so-so or mediocre?
You are trying to increase performance changing cam. A waste of $$$$ if you do not tune it properly. Best tunes are done by you. See dynamicefi.com. User friendly.
You are trying to increase performance changing cam. A waste of $$$$ if you do not tune it properly. Best tunes are done by you. See dynamicefi.com. User friendly.
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Race Director
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From: Overland Park Kansas
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I have a guy working on getting my 86 running. It has ported slp runners, ported stock base, ported plenum, TFS-30300001 heads with the lt4 springs, and more. We put the sum-1065 cam in, which is different than what they have online now. my specs are 216/216 duration at 050. The mechanic is concerned that online it states that this cam is not computer compatible. He says, "This normally means that you have to modify either the fuel mapping or the spark mapping or both." Is this true?.
Regardless of cam.
You risk going too lean and hurting your new engine w/o a scan and/or new chip to compensate.
Last edited by GREGGPENN; Jul 17, 2013 at 05:08 PM.
Thread Starter
Racer
Joined: Jul 2007
Posts: 462
Likes: 21
From: Kansas City Missouri
Gregg..good to hear from you after such a long time. :o) I can't remember what lb injectors it comes stock with, but when I was putting it together it seemed all evidence pointed to the fact that the stockers would support the mods. I spoke to the mechanic today and told him we could pull the trigger on a new chip any time he felt ready, so we will see. So tired of being down. Looking forward to actually having something I can drive.
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
my last 2 cams have been listed as "computer controlled compatible - No" and yet surprisingly my computer did control them, maybe its just a very controlling computer ? 
the main thing with the cam is the duration (which yours doesnt have a lot) and Lobe Separation Angle, i looked at that cam on summit, i know you said its not exactly the same specs, but that one is 110 Lsa, how much is yours ? the stock chip in a MAF set up would handle 216 duration no worries but prob not 110 lsa,
the 3 big changes that will necessitate a chip upgrade are; big increase in duration, decrease in LSA, and bigger injectors,
I think the main question with your set up is what is your cams LSA ?
the main thing with the cam is the duration (which yours doesnt have a lot) and Lobe Separation Angle, i looked at that cam on summit, i know you said its not exactly the same specs, but that one is 110 Lsa, how much is yours ? the stock chip in a MAF set up would handle 216 duration no worries but prob not 110 lsa,
the 3 big changes that will necessitate a chip upgrade are; big increase in duration, decrease in LSA, and bigger injectors,
I think the main question with your set up is what is your cams LSA ?
Team Owner
Joined: Sep 2003
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
#22 injectors are stock
Without sounding sarcastic..
I'm confused why C4 owners will spend so much money modding their engines then stop short of spending the money for a tune. I had my stock 86e tuned and found the results to be very impressive. When I swapped in a more aggressive cam, the re-tune proved to take advantage of the mod and the SOTP results have been most impressive. Haven't taken it to the track yet, but the stock (tuned) numbers were 13.9 @ 99mph.
Without sounding sarcastic..
I'm confused why C4 owners will spend so much money modding their engines then stop short of spending the money for a tune. I had my stock 86e tuned and found the results to be very impressive. When I swapped in a more aggressive cam, the re-tune proved to take advantage of the mod and the SOTP results have been most impressive. Haven't taken it to the track yet, but the stock (tuned) numbers were 13.9 @ 99mph.
Race Director
Joined: Sep 2003
Posts: 16,838
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From: Database Error Indiana
#22 injectors are stock
Without sounding sarcastic..
I'm confused why C4 owners will spend so much money modding their engines then stop short of spending the money for a tune. I had my stock 86e tuned and found the results to be very impressive. When I swapped in a more aggressive cam, the re-tune proved to take advantage of the mod and the SOTP results have been most impressive. Haven't taken it to the track yet, but the stock (tuned) numbers were 13.9 @ 99mph.
Without sounding sarcastic..
I'm confused why C4 owners will spend so much money modding their engines then stop short of spending the money for a tune. I had my stock 86e tuned and found the results to be very impressive. When I swapped in a more aggressive cam, the re-tune proved to take advantage of the mod and the SOTP results have been most impressive. Haven't taken it to the track yet, but the stock (tuned) numbers were 13.9 @ 99mph.
No reason to not take full advantage of the hard parts installed. If you have the time and are willing to learn tuning has rewards. I have done 100 tunes just playing with fuel. Premium, E 85, E 30, depends on the price at the pump. Then I go to the track and see how much advance I can give it and still launch without spinning the tires. That depends on the air and track prep. Lots of datalogs and lots of tunes. Guess I am easily entertained.
Thread Starter
Racer
Joined: Jul 2007
Posts: 462
Likes: 21
From: Kansas City Missouri
#22 injectors are stock
Without sounding sarcastic..
I'm confused why C4 owners will spend so much money modding their engines then stop short of spending the money for a tune. I had my stock 86e tuned and found the results to be very impressive. When I swapped in a more aggressive cam, the re-tune proved to take advantage of the mod and the SOTP results have been most impressive. Haven't taken it to the track yet, but the stock (tuned) numbers were 13.9 @ 99mph.
Without sounding sarcastic..
I'm confused why C4 owners will spend so much money modding their engines then stop short of spending the money for a tune. I had my stock 86e tuned and found the results to be very impressive. When I swapped in a more aggressive cam, the re-tune proved to take advantage of the mod and the SOTP results have been most impressive. Haven't taken it to the track yet, but the stock (tuned) numbers were 13.9 @ 99mph.
Team Owner
Joined: Sep 2003
Posts: 20,179
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From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Call PCMforless. They can develop a basic tune that will be based on your mods. Refinements will be required, but at least it will run well enough to break in the cam and record a datalog or two
Safety Car
Joined: Nov 2009
Posts: 3,973
Likes: 341
From: Adelaide South Australia
My intention has always been to get it tuned. The problem is that we are having difficulties in getting it running, which brought up the question, is this non-compatible cam going to make it run ok....not optimally, but run ok. This was not a question of can I get away with not tuning the car.
like mrwillys said a good tuner should still be able to do a good tune for it, its probably the 110 lsa that is upsetting the stock chip the most.