Jul 13th, 00, 03:11 PM
I have a couple questions, and maybe someone can help me out. I have a 79 Z28 with a TH-350 auto trans. My first question is general. Are all TH-350 transmissions built the same? Would one from 1970 be the same as one from 1988?
And now a more specific question. The car originally had 170 HP (blech!) from the factory. I have built the engine up by replacing everything but the block, crank, and pistons. The car is now around 350 HP and 400 lb of torque. The powerband is from about 3000-5500 rpm. The car cannot spin the tires at all. My friend's 91 IROC has less power than mine, and can spin all day. I think maybe I need a higher stall torque converter, but heck if I know what the deal is. BTW: the car is a monster when it kicks into 2nd gear and up. It just feels sluggish in 1st gear. Like when your in stop and go traffic and do a lot of coasting. You get the picture. Any ideas would be appreciated. Thanx!
Jul 13th, 00, 05:11 PM
I would say a looser converter would help greatly. It will get you up into the powerband quicker...
If you are going to drive this thing on the street....I would recommend staying around a 2500-2800 stall....not much higher.....
Steve McCorry - Central Ohio Camaro Club
'69 Camaro RS/SS-350 - Daytona Yellow
'95 Camaro Z-28 - Sebring Silver
click here to see my car ---> www.mindspring.com/~mccorry (http://www.mindspring.com/~mccorry)(updated 7/1/00)
Jul 13th, 00, 05:19 PM
You didn't say but IMO you will need to run a 3.73 rearend in the beast to get it quickly in it's power range.
2500 Stall as already suggested would also help. Check your timing and make sure you are running enough ADVANCE. Your total timing should be around 36 degrees all in around 2800RPM.
If you are running a holley make sure your carb's accelerator pumps are adjusted properly. If they are too loose, you will experience a bog off idle.
Jul 14th, 00, 05:20 AM
Your friend's IROC probably has a better overall first gear ratio than your car. The overal ratio is the tranny first gear ratio times the rear gear ratio. When GM built these cars, they made sure that they had a great take-off by giving them a low overall gear ratio in first.
Also, if your powerband starts at 3,000 RPM, you won't ever have that great of a take-off. A good STREET engine's power band should start around 1,500 to 2,000 RPMs. The tuned port motor provides the IROC with a lot of torque just off idle.
Finally, if your car catches up and passes your friend's IROC, why do you care that it doesn't spin the tires? My 500hp supercharged beastie doesn't spin the tires well either (and that's with 3.73s in the rear). But after it gets up to 4,000 RPMS, watch out!!
Jul 14th, 00, 11:43 AM
Couple of questions about a torque convertor. How difficult is it to remove the transmission from the car? I haven't ever removed one before. Is it hard to install the convertor itself? If I can't do it, can I take it to a transmission shop and have them do the work? Also, can I continue to drive the car as it is now? Or will something terrible happen to the transmission? BTW: where can I find my rearend axle ratio? You guys are great! Thanks a lot http://www.camaros.net/forum/smile.gif.
Jul 14th, 00, 02:09 PM
The tranny won't be too fun to get out...the bolts are a pain to get to and the tranny is HEAVY!
The gear ratio will be stamped on the outside of the ring gear....will look like:
43:14 .... which is a 3.07 for example.
Jul 14th, 00, 06:52 PM
If you do decide to do it your self,get a buddy to help with the muscleing,and rent a tranny jack,instead of using a floor jack.I always was to cheap/broke to go out and rent one.I think my tranny swap/tranny falls off floor jack and onto the ground ratio was about 10/10.I'm getting to old for that.
67 RS RAGTOP # matching
4X4 Chevy truck
[This message has been edited by 67drake (edited 07-14-2000).]