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Need help optimizing my 86 vette's tune

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Old 10-26-2004, 08:00 AM
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darkman5001
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Default Need help optimizing my 86 vette's tune

Okay guys, as some of you may know, I got my a** handed to me by a 2001 Mustang GT with shift kit, high stall torque converter, and 4.11 gears. Here are my current mods...


-Remanufactured Jarco 355 Short Block about 13k ago
-(I found a core tag in with the paperwork for the engine that
says part# 87 Chevy 350 4 bolt roller. ) Does this mean
They put in a motor for 87 with 4 bolt, and roller?)
Stock Cast Iron heads removed from old engine and
onto new engine. To my knowledge, the cam is stock.

Brand New GM Auto Transabout 20k ago

Magnaflow Catback system (15658)

Random Tech Super High Flow Catalytic Converter (200-402)

Hooker front Y-pipe with NO pre-cats Jet-Hot coated inside and out (H16720)

Hooker Super Competition Long Tube Headers Jet-Hot coated inside and out (H2149)

Bypassed SMOG system

SMOG pump delete pully installed

MSD 8.5mm Spark Plug Wires

Summit High Torque Starter

Holley AFPR

24Ib Ford Motorsport Fuel Injectors (blue)

52mm Throttle Body by David Koldos

Bore-Matched 52mm airfoil by David Koldos

Throttle Body coolant bypassed

180F Thermostat

K&N Air Filter with Stock air box and cut air lid

Chip done by Ski_dwn_it



I also looked under the driver’s side storage compartment in hatch area and wrote dow the codes in there:

A69 AQ9 AU3 A42 BGR B3W CC3 C49 C68 DL8 D3X D9B E5Z E9Z FG3 G44 G92 KB2 K34 K68 L98 MD8 MX0 NA5 PY3 QZD UQ4 UU8 V73 Z6A 1AY 121 122 410 64S


BSE/CLR COAT WA-U8555



Base timing has not been tampered with since Engine World installed the engine, so I assume it has the stock base timing set.

Fuel pressure was set at 47psi w/o vacuum.

I don't yet have a datalink to hook the car to my laptop, but I'm working on it. I have never dynoed the motor either. Also it has stock fuel pump installed about 5 years ago.


I guess what I need help with is tuning the thing. If and what else do I need to upgrade or replace? What should I set the AFPR to for best performance, and what should I do about base timing? Also, what else do you guys recommend?


I have NEVER been to the track before, even as a spectator, but Mr. Mojo invited me to come up on the 6th, so I am probably going to do that since I am off that day from the base. I looked on Englishtown's website, and from what I understand, they are doing time trials. I would like to run my vette and see what she does. Hopefully, I get to me some of you. I hope to learn a great deal. Anyways, please give me your input on the above. Thanks Guys.


Scott
Old 10-26-2004, 08:11 AM
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rick lambert
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Just looking at your mods-I think you should have taken the stang-that being said, from your previous post it sounds like two basic things, #1 get rid of the bald tires, you need to grab, #2 with his 4:11s he's gonna beat the crap out of you every time from the hole, check your rear ratios. I'd think with some good rubber and maybe some stiffer gears-you'd get him red faced! I shoulda read a little closer-an 87 with iron heads? did I read that right-if so you may need work there also. Sorry-you've got an 87 block in a 86-shoulda upgraded the heads then. Newer heads and good rubber-maybe the gears=no contest.My .02$ worth.And I'm not saying the stangs are slow.

Last edited by rick lambert; 10-26-2004 at 08:15 AM.
Old 10-26-2004, 08:20 AM
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darkman5001
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Originally Posted by rick lambert
Just looking at your mods-I think you should have taken the stang-that being said, from your previous post it sounds like two basic things, #1 get rid of the bald tires, you need to grab, #2 with his 4:11s he's gonna beat the crap out of you every time from the hole, check your rear ratios. I'd think with some good rubber and maybe some stiffer gears-you'd get him red faced! I shoulda read a little closer-an 87 with iron heads? did I read that right-if so you may need work there also. Sorry-you've got an 87 block in a 86-shoulda upgraded the heads then. Newer heads and good rubber-maybe the gears=no contest.My .02$ worth.And I'm not saying the stangs are slow.

I don't know for sure if it's an 87 block. That is just what this core tag says with the paperwork for the motor. How can I find out? Also, how hard is it to install taller gears, and what would be the max ratio I should install? Are my heads worth anything as far as working, and would that be cost effective? Thanks!
Old 10-26-2004, 08:53 AM
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rick lambert
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Well, first of all-you need to can the bad rubber not only so you can grab, but for safety issues-with bald tires you'll smoke em all day and get smoked all day. While it's up in the air for tires, have them check your gear ratios, simply marking your tire and the drive shaft-rotating the tire one rev. and counting the number of rotations of the drive shaft should get you real close to knowing the ratio.Others will chime in about what gears you can go to-but in my opinion have some one who knows how to do it change them-if you haven't done it b4. I think the 87 aluminum heads are much better than the iron early 86s (I think aluminums were introduced in late 86), but tires and gears should help you spank that stang.
Old 10-26-2004, 10:59 AM
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First, you have a 3.07 rear axle ratio. With the auto, a 3.54 gear is probably the max for a stock cam and TPI intake, for the drag strip. A looser converter will give up the most bang for the buck. The cast iron heads CAN be improved upon, but unless YOU are doing the work, it will cost more than any potential improvement is worth. A moderately priced set of aluminum heads will give you more for little or no more money. I wouldn't think of messing with fuel pressure until you can get some A/F ratio readings to SEE what it needs. For your set up, it can't be too far off. You CAN mess with the base timing. Set it up, 2 degrees (8) and make a few 1/4 mile passes. Compare that with the stock, 1/4 mph. The go up 2 more. Keep advancing until the 1/4 mph starts to drop off, and then go back to the previous, best setting.

As it sits, it looks like a mismatched selection of headers, TB, and injectors, with a stock cam and heads. With those injectors, it may need LESS fuel pressure. Some diagnostics and a good tune up MAY help, however, knowing Jesse, you probably DO have the best tune up for your combination.

RACE ON!!!
Old 10-26-2004, 11:43 AM
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redfast
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Originally Posted by CFI-EFI
First, you have a 3.07 rear axle ratio. With the auto, a 3.54 gear is probably the max for a stock cam and TPI intake, for the drag strip. A looser converter will give up the most bang for the buck. The cast iron heads CAN be improved upon, but unless YOU are doing the work, it will cost more than any potential improvement is worth. A moderately priced set of aluminum heads will give you more for little or no more money. I wouldn't think of messing with fuel pressure until you can get some A/F ratio readings to SEE what it needs. For your set up, it can't be too far off. You CAN mess with the base timing. Set it up, 2 degrees (8) and make a few 1/4 mile passes. Compare that with the stock, 1/4 mph. The go up 2 more. Keep advancing until the 1/4 mph starts to drop off, and then go back to the previous, best setting.

As it sits, it looks like a mismatched selection of headers, TB, and injectors, with a stock cam and heads. With those injectors, it may need LESS fuel pressure. Some diagnostics and a good tune up MAY help, however, knowing Jesse, you probably DO have the best tune up for your combination.

RACE ON!!!

Yes, this sounds good. You can make this thing go alot better. Go to the track and play with the timing. And fuell pressure. I think the only reason that you have to run those ford injectors at a lower pressure is because ford rates those at 24# with 38pressure going to them(i think) and gm rates there injectors higher. Somthing along those lines.
And maybee the main reason that he beat you is because it was your first time to the track. So he may have more race's under his belt. Depending on the day but lets say i got to the strip and i get a 12.5 in the quarter. I let one of my friends drive and he's raced many times too, but he ran almost 2 seconds slower. Practice makes perfect.
Old 10-26-2004, 03:37 PM
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darkman5001
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Originally Posted by CFI-EFI
First, you have a 3.07 rear axle ratio. With the auto, a 3.54 gear is probably the max for a stock cam and TPI intake, for the drag strip. A looser converter will give up the most bang for the buck. The cast iron heads CAN be improved upon, but unless YOU are doing the work, it will cost more than any potential improvement is worth. A moderately priced set of aluminum heads will give you more for little or no more money. I wouldn't think of messing with fuel pressure until you can get some A/F ratio readings to SEE what it needs. For your set up, it can't be too far off. You CAN mess with the base timing. Set it up, 2 degrees (8) and make a few 1/4 mile passes. Compare that with the stock, 1/4 mph. The go up 2 more. Keep advancing until the 1/4 mph starts to drop off, and then go back to the previous, best setting.

As it sits, it looks like a mismatched selection of headers, TB, and injectors, with a stock cam and heads. With those injectors, it may need LESS fuel pressure. Some diagnostics and a good tune up MAY help, however, knowing Jesse, you probably DO have the best tune up for your combination.

RACE ON!!!

What are the procedures for adjusting the timing, and what do I need to make adjustments accurately?
Old 10-26-2004, 06:53 PM
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Anyone?? Timing procedures??
Old 10-26-2004, 07:22 PM
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I believe Rick is right about the heads, though for the life of me I can't remember if the 113s D-ports started in 87 or 88. Either way, supposing you have 85-86E heads on a stock"ish" 87 motor. You have some very mismatched components. And that could put you worse than stock.
I wouldn't recommend porting those heads, just get some nice big ones. A cam swap is easy in a roller block, and wham bam there a nice little motor there.

As for tires, get some good ones, that will really help out of the hole. However, if he can drive, and you can't. It doesn't matter if you are in a McClaren f1 (ok maybe that would ) but he will kill you. Go out and practice launching, minimal spin maximum acceleration. Get a G-Tech and you can record 1/4 mile runs, just practice till you get better and better.
And have fun, its still only a rustang...
Old 10-26-2004, 07:24 PM
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USAsOnlyWay
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Originally Posted by CFI-EFI
knowing Jesse, you probably DO have the best tune up for your combination.

RACE ON!!!

What if he tuned the engine basing it on the fact it was a different one than this 87 block he found out he had. Could be the tune is dead on...for components that aren't there!!!
Old 10-26-2004, 07:41 PM
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Originally Posted by USAsOnlyWay
What if he tuned the engine basing it on the fact it was a different one than this 87 block he found out he had. Could be the tune is dead on...for components that aren't there!!!
What does it matter whether it is an '86 or an '87 block, for the tune? Even if the '87 has a roller cam, it is virtually the same as the '86 flat tappet.

Originally Posted by darkman5001
What are the procedures for adjusting the timing, and what do I need to make adjustments accurately?
Based on the question, I'd say a timing light, a distributor wrench, and a Helm's manual. www.helminc.com

RACE ON!!!

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