Hyperpolarized (HP) [13C]bicarbonate MR imaging can map pH in vivo, but images generally suffer from low CO2 signal-to-noise ratio (SNR). However, rapid bicarbonate-CO2 chemical exchange can increase CO2 SNR via exchange-mediated polarization transfer. We exploit this phenomenon for HP [13C]bicarbonate imaging to boost CO2 SNR by 2.2-fold at pH 7.6, where CO2 SNR is lowest in the physiologic range, by acquiring and summing multiple transients. Tip angles and delays are chosen using a priori knowledge of exchange rate to increase SNR while mitigating pH error. This approach can potentially improve imaging SNR in vivo for studying extracellular acidosis in cancer.