Heat Riser Question

[Gene M.]

Re: Heat Riser Question

Remove the plate (or butterfly flapper) with a Dremel cut-off wheel. When re-installed it will look, feel and react as if it had never been altered. No deducts in judging either.

Don

Not true. In cold start operations the exhaust will be coming out both pipes. Which is a deduction for failing to function.

[Joe L.]

Re: Heat Riser Question

IMO, a shield under the carburetor to extend beyond the float bowls to deflect the heat would make a big difference. I think GM used a shield in later years and probably for that same reason, they also kept using a heat riser.

Timothy------


Yes, these were used but only for some 1970-71. They can be retrofitted to others.

Holley 4 barrel insulation------GM #3999198 (long-since discontinued but may be available in reproduction).

Q-Jet insulation------GM #3969837 and, later, GM #10147945 (both discontinued but may be available in reproduction)

Dr. Rebuild would be a likely source for either of these.