Who said 4.10+ gears will wear on an engine? Compression Test Results

milw96cobra · 07-17-2003

Well boys... in my ever growing pursuit of proving all you 4.10+ gear naysayers wrong, I've come upon another fact to disprove your theories.

It's been ~15,000 miles with the 4.30's.... 50% highway 2700-2900rpm driving, 40% city 2500rpm driving, and 10% giving it some gas driving....

My car now has ~71,500 miles on it.
Compression test on the engine, results are as follows

(~190psi is brand new from the factory, when they get to 150ish psi, is when you need to start worrying)

#1 - 186psi
#2 - 182psi
#3 - 184psi
#4 - 185psi
#5 - 179psi
#6 - 173psi
#7 - 180psi
#8 - 178psi

Well folks, there you have it.... my engine still compresses at almost new psi numbers, the only questionable cylinder would be #6, and its WELL within tolerance.... so I guess the higher rpm driving with the 4.30 gears doesnt affect it as much as we thought... eh?!

CombatStang · 07-17-2003

NICE!

1998GT · 07-17-2003

Excellent numbers Milw, very good!

96greenGT · 07-17-2003

Nice indeed.

BigAlMo · 07-17-2003

Sweet, I have 4.10's (not installed yet though) thinking more along the lines of 4.30's though. Hummm. Can't make up my mind for sure.

Very nice on the results though.

Mana4Real · 07-18-2003

Looks like your left bank is a little bit lower then your right. Is there anything that could cause that?

milw96cobra · 07-18-2003

Lots of things could cause it, but theyre still well within tolerance...

mgranzow · 07-18-2003

Quote:

Originally posted by Mana4Real
Looks like your left bank is a little bit lower then your right. Is there anything that could cause that?

it was dark outside.. we were trying to get finished before we completely ran out of light since we were working outside.

Kevin62773 · 07-18-2003

Do you think this is because you have run a very good synthetic motor oil and changed often?

1998GT · 07-18-2003

It is because of well engine matience and because you dont beat the crap out of ur car and your inteernals.

97Red248A · 07-18-2003

Very nice Milw. But what I find more facinating is 96greenGT's avatar.

As "Butthead" used to say, "that was the coolest thing I have ever seen".

Light em up......

Twokingsracer · 07-18-2003

Quote:

Originally posted by milw96cobra
Well boys... in my ever growing pursuit of proving all you 4.10+ gear naysayers wrong,

Ever growing...man you are either really dedicated or have a hard time letting go of a grudge...you guys should just fight out by the bike rack or something. Anyway...great numbers.

rnner3200 · 07-18-2003

how do you do a compression test? how much would that cost and what is it telling me?pardon my ignorance but i think this is the best place to learn.

97Red248A · 07-18-2003

One big thing a compression test will show is whether a head gasket is blown if suspected. If 2 or more cylinders have extremely low compression, its time to replace the gasket. It will also give a person an idea on the condition of the cylinder walls and and rings, as Milw96 pretty much said.

Fallguy · 07-18-2003

That's good to know. Nice number's . I'm glad they held for you. Your car has all forged internal , correct ? I wonder if the 2v would hold up just as good ?

I got my 3.73's in the mail today. I hope I'll like them . They just sounded like a perfect gear for me, but time will tell. I know live and learn,but in a prev. post you called us ignorant for getting 3.73's.If I don't like the 3.73's I'll swap to 4.10's or If I decide not to go S/C next year then I might. The gear's and swap are pretty cheap so I'm not worried about it.

I can only imagine how your car pull's with 4.30's . It must be a blast !!

One more thing that scared me away was people alway's talking about traction issue's with 4.10's. I plan on keeping my stock size rim's & tire's , so what would happen with the 4.10's ? Would I just spin all the time ?

Clue me in guy's
Fall