Hmm...trying to figure out if this caused my blown hg's.

CaifanSC

SCCoA Member
It's a bit of a stumper since some of the stuff I put into the car was precisely to PREVENT headgasket failure. I want to try and figure out what caused it so that I can address the issue and not do the same once I fix the car.

1- I'm thinking if perhaps overdriving the 94 blower had something to do with it. I've got the 10 rib ESM quick change set which I understand is about 12% overdrive. I know there are mixed feelings about putting a 10% overdrive pulley on a 94, so im guessing that perhaps going with the 10 rib kit was the cause of my hg failure. I'm not sure though, since alot of people have not had problems with 10% overdrive on their cars with the late style blower. I had a free flowing exhaust (kooks midlengths, and 2 1/2"-3"-2 1/2 cats and resonator w/no muffs), ARP head studs and not many big induction mods, and stock heads.

2- Another posibility was that i just screwed up in the re-assembly process since this was my very first rebuild even though I used Fel-Pro gaskets (no multi layer) on block/heads that were checked for squareness, and torqued the ARP studs to the correct torque in the correct sequence.

3- There's always the possibility of the heads being cracked, but they were checked in the machine shop and came out ok, aaaand, if they were faulty then the problem should have appeared even before I had the mods in place. I drove the car for about 2000 miles before doing most of the upgrades (ESM kit/exhaust) and the car ran fine.

4- Was it perhaps a lack of tune? The car had a small idle problem and was running a bit rich according to the EEC codes (o2 sensors), A/F ratio gauge and black smoke in the tail pipes, but I really didnt upgrade much electronic stuff. Still running stock 30Lbs injectors, and a MAF thats calibrated for those injectors. I doubt that the slight increase in displacement messed with the overall programming of the EEC (block was bored 20 over).

Just a bit of detail, after adding the go fast goodies and exhaust upgrades I took the car out for a drive, it responded great and had a mean sound ( a bit too loud b.c of no muffs but tahts another story) so I got on it pretty good. When i get back home from the test drive I see bubbles in my coolant bottle and the upper rad hose was expanded, but no white smoke or any other signs of blown hg's (oil in coolant or vice versa). I had to perform a sniffer test to confirm that the coolant is getting pressurized with exhaust gases and only after getting hot. AFter re-starting the car when cold there are no bubbles but as soon as it gets hotter, u see the bubbles.

What do you think caused my blown hg's?:confused: :confused:
 
Well that specific MAF i bought from a fellow member, it came out of his SC and I just got the housing/sample tube. The electronics are the my stock MAF electronics.
 
What color is sampling tube?...there should be a magic marker strip on it..in a color..Just want to rule that out
 
Im running the 'clear' or 'silver' tube on the MAF housing so unless i'm mistaking thats for stock 30# injectors. When i first got the car running it had the idle problems a bit worst so i swapped the C&L with the stock maf housing and saw no difference so i've tried both mafs with the same problems.

As far as fuel goes, i attached the fuel pressure gauge to the fuel rail and i had about 40 psi at idle and increasing evenly when i pulled on the throttle. I do still have the stock fuel pump (225k+ yuk!) but it seems to be working fine still. I do have a high pressure 225lph sitting in my basement but i didnt want to install it just yet since my original pump still works fine. According to the symptoms and codes im not having fuel starvation and running lean, its apparently the other way around, im running rich. Odd huh?:confused:
 
well i will tell you, i just did my headgaskets, and i get sometimes the bubbles in the overflow, but i think thats cause my thermostat housin my be leaking by the headgasket, does it over heat? when you step on it does the temperature go past the NORM and not be able to come back down on its own? cuz if it does that then most likely yes ur headgasket is blown, mines was blown but only under boost, when you put the car in boost it would fill up the cooling system and overflow the radiator reservoir like whoa! anywho, you might want to do a cooling system pressure test and see if it holds pressure...

mines is doing the same thing right now, and i just redid the headgaskets, but for the couple of times ive been smashing on it, she is holding good temp, something its never been able to do before! :D
 
As far as fuel goes, i attached the fuel pressure gauge to the fuel rail and i had about 40 psi at idle and increasing evenly when i pulled on the throttle. I do still have the stock fuel pump (225k+ yuk!) but it seems to be working fine still. I do have a high pressure 225lph sitting in my basement but i didnt want to install it just yet since my original pump still works fine. According to the symptoms and codes im not having fuel starvation and running lean, its apparently the other way around, im running rich. Odd huh?
No, not really. Fuel demand will be highest @ top RPM. At lower RPMs the OE fuel system will still be enough though.

I have similar mods to you, and I am currently out of fuel with the OE pump and 30 lb'ers! Mine starts leaning out pretty bad above 4,000 RPM, but below that is somewhat OK (I have 38's and a 255FI pump just waiting to be installed in mine). Your Autometer should be enough to see this "leaning out" at high RPMs/WOT, but you have to watch the gauge carefully.
 
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