Car: 1987 Pontiac Trans-am GTA
*Engine: 355sbc "10" block assembled by Summit (325h.p/350 longblock)

Bottom: KB hyper 9.2:1 C.R.,Summit Crank,rods
Cam: Hydraulic 222*dur. .450"lift 114 LSA
Heads: L-98 Aluminum 58cc Stock unported
Intake: Edl.base, Superam upper,52mm t.b.
Fuel: 24lb.SVO, AFPR, Walbro 255 pump\
Power
adder: Paxton(85-87)base blower kit
ECM: Stock harness-FIS adapter-Accel DFI
2-bar map
Tuner: Arizona Speed and Marine

*Used turn-key engine bought used with DFI


I Have a Problem. Car starts and runs fine for a while. As soon as it has been idling for 5-7 min. approx. I turn it off. Now, the problem is that it would NOT start up again. So I try to crank it and the engine turns and thats followed by a "click click" noise which then I know It would not start up again. I wait till the next day after the car is cooled off and it starts up perfectly fine. SO WHY DOES THE ENGINE START UP PERFECTLY ONLY WHEN ITS COLD?


Ignition setup:
Stock small diameter Distributor with
MSD GM divorced coil
MSD 6AL with MSD plug in harness
MSD Super conductor 8.5 wires

 

the starter's getting heat soaked?

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ICON Motorsports

1st & 3rd

 

It could be some wires going to your battery "acting" up it could be some wires to your starter acting up Wiggle them around next time it doesnt start that might be it
Atleast thats what it sounds like to me... But then again im no expert

 

Heat affecting the starter (or wires)...heat builds up resistance...check all the connections first from the battery to the starter. If all is good with NO CORROSION, then it is probably the starter itself.

 

Thats exactly what my neighbor who's excellent in diagnosing mechanical problems taught it was. Now I'm going to throw another theory out there from a mechanic who took a look at it.

HE SAYS ITS THE PICKUP COIL IN THE DISTRIBUTOR OR THE MODULE

What he did was test for spark by unplugging the plug wire and putting a screwdriver in it to see if there was "juice". As the engine attempted to start no spark was present. I did the MSD box check, which is unplugged the white wire and coil wire and ground them nearby for a spark to travel in between. The test was positive. Furthermore, we bypassed the MSD ignition box once this "heat soak" condition was present and that did nothing so we know the box is doing its job.

The heat soak condition of the starter was the first thing that crossed my mind but I eliminated that possibility by wrapping the solenoid with that special heat shield cover material they sell especially for that and IT STILL DOES IT.

My neighbor mechanic said to check the ground cable from battery to motor. So since it was attached to the aluminum heads, I moved it down to the cast iron block and sanded it. That still did nothing to solve this problem.

Another possibility would be the two grounds attached behind the heads. Since I converted to aluminum, the grounds should still have a strong contact point right? I think I've almost eliminated this factor cause the fuel pump is working perfectly fine everytime the ignition is in the on position and since the fuel pump relay is grounded to this part of the head if there wasn't a good contact there it would not work.

That leaves the Distributor theory which two mechanics I have verbally spoken to of this problem seem to agree its either the module or pickup coil. He further attested to this by saying to unplug the pigtail that controls the timing advance and IF IT THEN STARTS YOU KNOW FOR SURE ITS THE DISTRIBUTOR.
I have yet to test his theory since I put the car at timing just the other day. How true can this be?

And finally, I will check first thing tomorrow all the starter cable connections to the solenoid and to the battery itself for anything that looks faulty.

Then I will decide to either replace the starter or the distributor. How do I know for sure it not one or the another?

 

Blown,

NOT a flame but that is a horrible cam for a blower. Not related to your problem but not helping matters, either. You gotta get more exhaust lift and/or duration...

 

TTT. Starter or distributor related my heat soak problem. How do I eliminate one or the other?

 

No malfunction in a distributor can possibly cause a starter to fail to turn the engine over. Now if the engine cranks and cranks and cranks but doesn't start when hot, it could be something in the dist; but if it fails to crank, it's either the starter, the battery, or a battery cable.

Check the battery (voltage at the terminals while it's malfunctioning) and cables and if all is well, get a CVR mini-starter. You won't believe the improvement over the stock crap.

BTW I agree about the cam; that 151 is a bad enough one for a N/A motor, but a total mismatch for a blower. You need something with less "advertised duration, more lift than a peanut cam, and about 12-15° more exhaust duration than intake. I'd be willing to bet that something like this would give you at least 50 more horsepower with no bad side effects.

COMPETITION CAMS CAMSHAFT SPECIFICATION SHEET

PART # 12-556-4
GRIND NUMBER: CS NX262H-13
ENGINE: CHEV SML BLK 265-400
INTAKE EXHAUST
VALVE ADJUSTMENT HYD HYD
GROSS VALVE LIFT .462 .480
.006 TAPPET LIFT 262 280
VALVE TIMING OPEN CLOSE
AT .006 INT 23 BTDC 59 ABDC
EXH 78 BBDC 22 ATDC
THESE SPECS ARE FOR CAM INSTALLED
AT 108 INTAKE CENTER LINE
INTAKE EXHAUST
DURATION AT .050 218 230
LOBE LIFT .3080 .3200
LOBE SEPARATION 113
THIS CAM SHOULD USE SPRING # 981-16

Note the "advertised" duration is almost 30° less, about the same .050", and .030"/.040" more lift, and more duration on the exhaust. Remember you've got a blower jamming stuff in on the intake side, but no "help" on the exhaust side. The dual pattern gives you that help.

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"So many Mustangs, so little time..."
ICON Motorsports

[This message has been edited by RB83L69 (edited January 21, 2001).]