im getting ready to rebuild my 305tpi ni my 85 z28. when i have it apart i want to install a crane compcam 2050 series cam. i know zepher you had this cam in your old 305 once. did you have to do any computer modifications to make the cam work correctly and be streetable? if it doesnt require mods i want to get the cam. i want to get atleast a low 14 sec out of the car. i know its capable of it with a fresh rebuild.

 

anyone have any clue

 

The 2050 is a large cam and I think you need to change springs, it also requires a stall on an Auto, according to the specs on jegs when I bought that cam 4 years ago.

I actually never got the computer to work right with my car.
I ran the car for 6 weeks in limp home mode and it ran great, but sucked down a lot of gas, about 6mpg in the city.

I found out way too late that my proms weren't being burned correctly. My version of the PP2 software was not compatible with Windows XP and wasn't burning them right, but the software looked like it was working, it verified and everything. After we figured out the problem, the motor spun some bearings.

Car ran a best of 14.1@99mph in Limp home mode.
86 LG4 block
87 TPI heads
87 TPI setup converted to a 91 SD system
Crane Cams 2050
Headers, 3" catback, custom y-pipe,
SLP Dual CAI
3.42 gears
T-5 tranny

I've done some research and I think I was running 10-10.5:1 compression since the LG4 heads and 87 TPI heads have a different compustion chamber size.

 

yea i was planning on new springs for sure. dont gotta worry about stall cause im goin T5. so you did have to do computer mods to make the cam work. mind you my car is an all true 85. i dont know if that makes a difference. its not a bunch of mix and match parts.

 

computer tuning will help but I think you may be able to get ok performance using stock.

I didn't have a chance to tune the car and run it with a good prom since the motor died on me.

But if you've seen the videos of my car, it runs pretty good in Limp Home mode, that is basically a fail safe mode that the memcal has if the prom goes bad.
I did a test the day the motor started knocking by running the car with the prom in the memcal and with the prom removed, the car ran the same so I know it was in limp home since there was no prom installed.

 

ok thats what i wanted to know. is if you could run the cam on a stock computer ro with just any aftermarket chip. what do you mean limp mode? is that mean its runnig without the computer? i just wanted a streetable cam without putting a bunch of computer work ni it. and i liked the way it responded when you put it in your car. sounded good and made good horse power. the one video i watched is when you first got it back together. damn that thing took off quick from a stop

 

Limp home is when the prom goes bad. I think the computer has to be pretty much 100% functioning though. It runs really rich.

 

the crane 114132 cam is a great cam. I love it so far. I was told that this is the max lift I could go with before having to mess with the computer. If so I think it was a very good choice for a cam for my 305. .440/.454 is the lift on it. Very good this would be my pick. Though not lumpy at all, it has the power band where I need it. Be sure to add a Torque converter to the mix for max results along with a full exhaust.

 

ever consider changing your rocker arms from 1.5 to 1.6 ratio?
your factory cam could have an increase in intake lift from .404 intake to .430 and your exhaust from .415 to .442......Has anyone else tried this? Ive never personally tried this but it sounds alot easier than changing a camshaft.

 

zepher, all 305 heads are pretty much the same, (after the late 70s anyhow) your 305 TPI heads had the same combustion chamber size as the LG4 heads, in fact they are the same head. the only reason compression was different on 305s was LG4s had dished pistons and the others had flat tops.

V6 camaro man, check the sig

 

My LG4 had flat top pistons, and had 9.5:1 stock compression,

 

dont get a compucam... get a an xtreme energy cam from comp cams.... something like the XE256H would be good on a 305.

http://www.compcams.com/Technical/Cu...ML/128-169.asp

also... i didnt see any headers in your sig. stock exhaust manifolds suck the big one.

 

so, zepher, what are you saying? you just stated that your flat tops in your lg4 had 9.5:1 compression. i was merely pointing out that all 305 heads starting in the early 80s had the same chamber volume. there really isnt one 305 head noticeably better than another.

 

So are you telling me that the TBI heads are just as good as the TPI heads? I know thats not true.

 

no i forgot to mention the swirl port TBI heads, everyone knows they suck

 

I was reading that the newer 305's have dished piston with 58cc heads to keep the compression 9.3-9.5:1 while my 305 with flat top pistons had probably 64cc or larger heads.

 

Check teh casting number of the heads. There were some differences.

It's no wonder the old 305 went belly-up on you. All that chain in the lifter valley couldn't have been a good thing for valve train reliability and lubrication.

 

yah, minor ones like valve size, etc. but i am sure that no 80s LG4s came with 64cc chambers, thats just plain wrong info. I'll repeat it again. starting in the early 80s ALL 305 heads are approximately 58cc, (not sure of the size of TBI heads but they arent the subject of debate anyway)

 

I recently installed a rebuilt 5.0 Litre from GM to replace the 5.0 Litre TPI engine in my 1989 GTA. At the time Hedman Hedders were installed and the catalytic converts were removed with an improved exhaust system. I will pass on my experiences. First, I had a choice to have the engine rebuilt locally or get a new or rebuilt engine from GM. If you go the GM route and stay with the same engine you get a 3 year warranty, which is something to consider. Second, I wanted a little more power, while still running smooth especially at idle, without sacrificing too much fuel economy. At the time I left the cam selection up to my mechanic. He went with the Comp Cam XTREME ENERGY XR258HR cam, which I have found to be good despite the LSA of 110. After researching cams and educating myself on their specifications I may have gone with an XR258HR to XR269HR cams. Here is the website for Comp Cams http://www.compcams.com/Technical/Cu...ML/128-169.asp . I also e-mail Comp Cams to discuss my cam with them and their response is noted on another thread. Third, I have discussed installing 1.6 ratio roller rockers to my set up in a thread below which you can read. These have been my experiences with new/rebuilt 5.0 Litre engines and cams.

 

Are you telling me that chain wasn't supposed to be in there?

 

I recently installed a rebuilt 5.0 Litre from GM to replace the 5.0 Litre TPI engine in my 1989 GTA. At the time Hedman Hedders were installed and the catalytic converts were removed with an improved exhaust system. I will pass on my experiences. First, I had a choice to have the engine rebuilt locally or get a new or rebuilt engine from GM. If you go the GM route and stay with the same engine you get a 3 year warranty, which is something to consider. Second, I wanted a little more power, while still running smooth especially at idle, without sacrificing too much fuel economy. At the time I left the cam selection up to my mechanic. He went with the Comp Cam XTREME ENERGY XR258HR cam, which I have found to be good despite the LSA of 110. After researching cams and educating myself on their specifications I may have gone with an XR258HR to XR269HR cams. Here is the website for Comp Cams http://www.compcams.com/Technical/C...TML/128-169.asp . I also e-mail Comp Cams to discuss my cam with them and their response is noted on another thread. Third, I have discussed installing 1.6 ratio roller rockers to my set up in a thread below which you can read. These have been my experiences with new/rebuilt 5.0 Litre engines and cams.



How much this GM rebuild engine cost? Do you have any idea how many HP on it? how many gallons per mile or better how many miles per gallon?


Thank's