Does anyone know of a company that will do a 3rd party on a modified car?

 

In a word, no. I have never, ever read a contract (and I read the contracts) that will cover a failure due to a fault related to a modification.

Having said that, there are two kinds of language you will see:
1. Any modificiations will void coverage. Yes, I use the term "void". With an aftermarket 'warranty' it is really a contract and a contract can void coverage under certain conditions. (A real warranty cannot- Moss Magnussen stuff)

2. Any failure due to a modification will result in loss of coverage for that failure. Do note that this is a HUGE loophole. For Example; "An exhaust with lower backpressure could increase power and may have caused that rod to exit the case: not covered."

Read th policy/contract- DO NOT rely of descriptions of coverage or conversations with the company.

A

 

Some contracts have big loopholes in them. The contract I have states that I have to perform all scheduled maintenance on the car as required by the manufacturer, and maintain verifiable receipts of such service which must be presented to the warranty company upon request. All recommended service must be done within 1,000 miles or 1 month of the requirement (i.e. 30k service must be done by 31k). Any missed service voids the entire warranty.

Really the only way to comply with this is to use a Porsche dealership for all maintenance and attach the receipts to the warranty contract. Fortunately for Porsches, required service intervals are only every 15k miles or annually.