Gen 1 with heads and cam

dicky

Enthusiast
Joined
Oct 18, 2019
Posts
11
Reaction score
1
Location
San Luis Obispo, CA
Just got my viper (1994) back from Dan Cragin today, this is exactly how I wanted my viper to be. I had him replace all the gaskets on the engine before they failed. While he was there I might as well have him add some power, so he added heads, cam, 1.73 rockers, full exhaust (Belanger with custom mufflers), and tuned. The cam is 232/238 @.050 with 610 lift and is very easy to drive.

The car put down 488 RWHP and 500 RWTQ on a mainline dyno (not sure how it compares to the common dyno jet).

Here’s a list of everything I had done plus the dyno sheet.
 

Attachments

  • 1D178AC1-67F9-450C-95CD-1E0C82212BBF.jpeg
    1D178AC1-67F9-450C-95CD-1E0C82212BBF.jpeg
    67.6 KB · Views: 30
  • F3646EFA-2A25-424F-9C3A-23F571D938AF.jpeg
    F3646EFA-2A25-424F-9C3A-23F571D938AF.jpeg
    52.8 KB · Views: 29
  • 36AEA296-C36C-4FD3-BE0A-3E956700560F.jpeg
    36AEA296-C36C-4FD3-BE0A-3E956700560F.jpeg
    83 KB · Views: 37
  • 38DA0449-05C9-4643-A879-EC656BEBDCE2.jpeg
    38DA0449-05C9-4643-A879-EC656BEBDCE2.jpeg
    97.2 KB · Views: 34

redtanrt10

Enthusiast
Joined
Oct 21, 2006
Posts
1,627
Reaction score
25
Location
Dana Point CA
Great numbers!!! One day I'll have Dan do the same with my '94 BTW, did you see my red comp coupe there?
 
OP
OP
D

dicky

Enthusiast
Joined
Oct 18, 2019
Posts
11
Reaction score
1
Location
San Luis Obispo, CA
Thanks

I think I did, I didn’t look at any of them too close. I was too excited to drive my new setup. Haha
 
OP
OP
D

dicky

Enthusiast
Joined
Oct 18, 2019
Posts
11
Reaction score
1
Location
San Luis Obispo, CA
I’ll have to get a video this weekend. It actually sounds pretty mild, which is what I told Dan I was looking for. I can’t let it sound to wild since I live in Cali for now and we have to smog here.
 

DickDavis

Enthusiast
Joined
Jan 20, 2022
Posts
5
Reaction score
0
Location
Florida
People tell me there were no chrome Gen 1 wheels yet mine has them and I see yours does too.
 

vprtech

Enthusiast
Joined
Sep 22, 2004
Posts
95
Reaction score
0
Location
L.A.
@ dicky: thank you for the feedback. Regarding Mainline hub dyno power numbers, I previously did a back to back comparison on a supercharged G3 Viper using my Mainline hub dyno and a Dynojet 248 making sure that the run conditions were the same, i.e. ambient temp, engine intake air temp, coolant temp and oil temp. I had to add 7% to match peak hp numbers and I would say 5-7% at lower rpm. The Mainline works similarly to a Superflow dyno software in that it records data in 25 axle rpm data points or “buckets”.

Tuning GEN1’s is an interesting challenge but I’m glad we can do them. Without tuning, drivability is terrible once you install a decent size cam: stalling or idle hanging when coming to a stop, rich running at idle, etc.

Fun fact, as some already know JTEC uses a 9*17 pulsewidth fuel lookup surface which is fairly straight forward to characterize , the SBEC ecu used on 92-95 Vipers also has a fuel table but is a 8 bit corrective map , which ties into a calculation that looks and engine map and some calibratable parameters in order to output a final pulse-width.
 
OP
OP
D

dicky

Enthusiast
Joined
Oct 18, 2019
Posts
11
Reaction score
1
Location
San Luis Obispo, CA
@ dicky: thank you for the feedback. Regarding Mainline hub dyno power numbers, I previously did a back to back comparison on a supercharged G3 Viper using my Mainline hub dyno and a Dynojet 248 making sure that the run conditions were the same, i.e. ambient temp, engine intake air temp, coolant temp and oil temp. I had to add 7% to match peak hp numbers and I would say 5-7% at lower rpm. The Mainline works similarly to a Superflow dyno software in that it records data in 25 axle rpm data points or “buckets”.

Tuning GEN1’s is an interesting challenge but I’m glad we can do them. Without tuning, drivability is terrible once you install a decent size cam: stalling or idle hanging when coming to a stop, rich running at idle, etc.

Fun fact, as some already know JTEC uses a 9*17 pulsewidth fuel lookup surface which is fairly straight forward to characterize , the SBEC ecu used on 92-95 Vipers also has a fuel table but is a 8 bit corrective map , which ties into a calculation that looks and engine map and some calibratable parameters in order to output a final pulse-width.
Nice to know about the dynos. I know very little about them, other than it seems most guys use a dyno jet. But the numbers aren’t too important to me, this thing moves really good now and that’s what is important to me.

I know y’all got the tuning figured out, this thing drives great now. I think it’s better to drive now than when it was stock.

Thanks for the great work!
 

Latest posts

Members online

Forum statistics

Threads
152,169
Posts
1,674,604
Members
16,504
Latest member
morgansiam
Top