Racing fuel advice, VP110 vs MS109

[vlzman]

Hi, When I bought my stage car from US then it had used mostly VP110 racing gas and was tuned to 110 octane and 22 psi of boost. Our racing organisation forbids using leaded gas, so I had to switch to MS109. I wanted to try at first without messing the timing and as a result I blew up my intake gasket. Please share some tuning tips I need to know to avoid any detonation in the future. ECU is bigstuff3.
thanks
Veljo

 

[turbodave231]

You damaged a head gasket or intake gasket? Detonation won't hurt an intake gasket.

What are your target A/F ratios?

Some people like flirtin with disaster and run AFR's in the high 11's. If this is where you are at with your targets, You may want to lower your targets into the 10.8-10.9 range to keep the engine rich. Do you have a log of the run when the damage occurred?

Dave

 

[vlzman]

You damaged a head gasket or intake gasket? Detonation won't hurt an intake gasket.

What are your target A/F ratios?

Some people like flirtin with disaster and run AFR's in the high 11's. If this is where you are at with your targets, You may want to lower your targets into the 10.8-10.9 range to keep the engine rich. Do you have a log of the run when the damage occurred?

Dave

Well, there the problems start. I'm quite sure that hurt was intake gasket as it looked crap and was sticked on the heads. Head gasket looked great the same time (both gaskets were felpros, 1026 and 1200). All I know is that week ago I discovered that my EGT was too high (between 900 to 1000) and that happened right after I had changed the fuel. And now I blew the gasket and mixed the coolage and oil. VP suggested to retard the timing 2 degrees and add fuel about 4-6%. Unfortunately I didnt log that race as I was in a hurry, got on the track, wanted to test new slicks but weather was bad and I wanted to do at least one race before it starts raining. So I dint have time even to warm the engine up.

 

[ijames]

If you just got this car maybe the intake gasket was hurt already from a backfire or something, and you just finished blowing it out? Retarding the timing will increase the egt's a little so don't be surprised by that. Definitely check the target afr, and why not start by turning the boost down 2-4 psi just to be safe?