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Need to rev beyond 9k. (1 Viewer)

Cadillac

Nitro Member
Hello.
Thank you in advance.
1427cc 4cyl. Dbl ohc. 4 valve. EFI.
Kinsler mechanical fuel pump.
4/1700cc injectors
Big coils.
Big port/valves
13:5:1
445/252° int 415/252° exh @.040
110/110 CL
250hp @ 12.5k on gas
260hp @ 12.5 on 100% methanol (big gains in tq)

On 25% nitro by weight
260hp at 9500rpm then flat on its face.
On 50%
273hp at 8500rpm then flat on its face.
But was not mis-firing or detonation.

The nitro mix of both %s made tremendous gains everywhere. (Big tq) over gas/meth.
The engine was originally built for a gas class. We did nothing to it accept the big fuel system and increase coil dwell 200%.
Adjust afr. Using O2 readings. (No egts at the moment.) dynojet.
This is our baseline.

Question: we need to get to at least 11k rpm. This is landspeed motorcycle.
We can sacrifice low speed/rpm. How?
Your observations and recommendations
please.

More CL 112-116?
More exhaust cam?

Is 11000+ achievable on Nitro with the right
modifications?

Thank you very much for any direction or recommendations.

Cad.
 

mike

Nitro Member
where is the intake open at .050 what is the duration what is the split -have you talked to your cam grinder?
 

Cadillac

Nitro Member
21° btdc, but that’s at 105 lobe center. @ .050.
16° at 110
Duration on the intake is 276°. 252 @ .050. Not @ .040.
But we haven’t kept great notes on the gas builds because they have been so predictable.
(I’m probably lazy too)
My cam grinder won’t talk until I’m ready to spend money. So I have dropped cores in the mail.
Once he has them, he’ll talk. Says he’s busy with the paying guys. I get it.
Thank you
 
Last edited:

mike

Nitro Member
21° btdc, but that’s at 105 lobe center. @ .050.
16° at 110
Duration on the intake is 276°. 252 @ .050. Not @ .040.
But we haven’t kept great notes on the gas builds because they have been so predictable.
(I’m probably lazy too)
My cam grinder won’t talk until I’m ready to spend money. So I have dropped cores in the mail.
Once he has them, he’ll talk. Says he’s busy with the paying guys. I get it.
Thank you
find a new cam grinder- bullet
 

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