strokervette

Well it's been awhile since I posted but I haven't really done much with the Vette since the motocross season started. I'm just finishing up some of my vacation time and over the last three days I got to install my new AFR heads and new cam. I got the 195 eliminators with the competition porting package #1095. I also got the Comp Cams 290AS-14 with new solid lifters. I threw on a billet timing gear set and a new double roller chain and was good to go. I didn't have to port match the gaskets as they were a perfect fit to the heads and the intake matched up good too. I chased all the threads in the block and lubed up the new ARP head bolts with assembly lube. They went in like butter! I also to the time to install a new power steering pulley as mine was warped a bit.

The initial start up was pretty good but I forgot to get the timing light out and ready and also to adjust the throttle screw. So it was a bit like emergency room havoc when me and my buddy were running around the garage trying to get everything done as the engine is warming up, I had to have him shut the camera off so we could do some quick tuning. Everything went okay after that but I didn't seal the bottom of the timing cover that well and had a small leak I had to fix. Also one of the cooling fans fuse case melted and the fan cut out and I was wondering why the temps were climbing into the danger zone. It was getting to the 25 minute mark as the temps got to the 230 mark so I shut her down and let her cool off to fix the leak.

Later that night I fired her up again and wanted to see where I stood with the A/F ratio so I hooked up the LM1 and proceeded to dial her in a bit. I set the idle to the point I could keep her running in gear which was about 950 in neutral and 600 in gear with a real nice lope. The next day I took her out to show my Dad and didn't yet realize the problem with the one fan not working and the temps were at the 215 mark when driving, but since he was only a few miles away nothing serious happened. We took the car over to one of his friends house and that where I found the problem. The plastic casing around the fuse melted from the intense heat on the breakin and in between the contact points. Right now I have it hardwired till I get a REAL fuse and now the temps never got over 200, and it was like 90 and sunny here today!

When I got home I messed around with the IFRs in the carb and set the A/F ratio. WOT was at 15:1 and cruise was 16.5:1 which was causing a surge while driving normal. I went from a 17 micron wire to a 14 in the IFRs on the primaries and left the secs alone with the staples that were in there from the last time I was messing around in there. I also changed the 80 sec jets to 84s and left the 68s alone in the front. Now, all is right on and I went out for a powerband check....... Now it pulls strong to 6000 rpm and when I shift it rocks you back into the seat hard! I want to get a little more time on her before spinning her up any further but next time I will have videos with the G-Timer. I got a few pics and videos from the project....Enjoy!

INITIAL START UP


SECOND START TO SET THE "IN GEAR" IDLE


LM-1 Data after the jet and IFR changes. In the middle of the pic the run started with idle, then I powerbraked it to 2k and mashed it! I couldn't get the real link to update so here it is on Photobucket.
http://s85.photobucket.com/albums/k4...nt=AFRdata.gif

gingerbreadman1977

awesome videos and good story to go with it mate. but next time put on a shirt. that body scared the s**t out of me.

strokervette

What are you talking about, that's 165lbs of lean mean Corvette tuning machine! It was like 95 degrees in the garage all week and it was hot. I'll make sure I cover up the goods next time.

gkull

Sounds great! What are 2461 heads?

thegazman

Ken

strokervette

2461 refers to the last four digits of the casting number on the heads, mine happen to be 1964-1965 "fuelie" heads. They have been port matched to the intake. But now I have the AFR Eliminator 195s.

To tell you the truth, I don't really feel that much of a difference, even after jetting it. It definitely lost a little bottom and gained it in the upper revs, also I haven't really ran her past 6200 rpm yet but she's still pulling at least. The bottleneck were the old iron heads, the cam "WAS" what the seller stated was in the engine as it said comp on one side and the grind number on the other(See sig for data on old cam).

What I'm getting at is I really thought there was going to be a big noticeable difference with new top of the line aluminum heads and a matching cam, but maybe there is still some tuning left in her. I pulled out the G-Time tonight and gave it a whirl but I was a little disappointed, 1.88 60' and 8.70 1/8 mile @ 336 average RWHP. I'll update the numbers as they get better. Anyway, according to the new head and cam specs I should be able to spray it with some juice, so if all else fails I have some room for NOS and still be on the safe side. The compression is lower now and runs great on 91 octane, not like before where I had some pinging problems when I pushed her hard.

strokervette

Since I was wasn't really impressed with the outcome of the new setup I decided to finally install the 2 step rev limiter and the 2 stage retard system on the MSD box. I also had to go a little richer on the primary jets and IFRs because it was surging while cruising and had a little hesitation while taking off with light throttle. I went back to the stock jet which is 71. I also now have the timing locked out at 37 BTDC but also have the start retard feature on the MSD box engaged which gives me a 17 degree initial and 37 running advance. With the 2 stage retard so far I tested it with 5 degrees so that brings it down to 32, but only after 3000 rpm. I had a hell of a time trying to figure out why I wasn't seeing it retard with the timing light when I had the switch on but then I realized that the feature only engages after 3000 rpm. I put some octane booster in her and went off to get some petro. A friend was with me so I had some extra weight in the car but when I was leaving the station to get on the highway I hit the loud pedal and the switch. WOW I never ever saw rpms climb that fast before. I shifted at 6500 6600 because I didn't want it to hit the 7000 rpm limit and when I grabbed second the tires chirped! That normaly didn't happen since I installed the M/T drag radials so it was quite surprising. I'll have to setup the in-car-cam again and post a fun video.

I might take off a couple more degrees on the retard feature bringing it down to 29 degrees. I recall seeing in some "performance mags" their notations about HP numbers taken with 29 degrees on their 383 strokers. Is it something about the config on strokers that they like less timing? All I know is I'm happy now. Next stage is a small shot of NOS!

Vette79C3

With the new cam, heads, lifters, etc. how come you didn't do a breakin of 25 min @ 2500 rpms? Just curious...

BKbroiler

Thanks for the detailed posts and the videos. Just one concern - that 1/8 mile time was way off where you should be, and where you were before. As you know, to go 12.8 or 12.9 in the quarter, you need a 1/8 time of around 8.1 or 8.2. Do you think your G-time device is off? I am just suggesting that you should be able to get more out of it before you add the spray. Good luck and keep us updated.

strokervette

I did do the 25 minute break in @ varying rpm over 2500.

strokervette

It was on the money last year when I went to the track. I did an initial run days prior to the track and both were 12.85. I'm anxious now to see what she can do, but your right about the 1/8 mile times, it was faster last year @ 8.2 seconds. My mph was on the low side as well @ 104. Right now since I can't get to the track due to my work schedule I am limiting my runs on the street to short bursts like the 1/8 mile and 60' times so I'm not going that fast. I have a deserted airport road nearby and there are no other cars around. It's also only about 1/4 mile long so I don't have enough room to slowdown safely. My main concern right now is using the diagnostic equip like the LM-1 and the G-timer along with adjusting the ignition box to achieve the best setup before going back to the track.

I'm going to re-check the valve lash, change the oil and install new plugs before I go too.