Fitch Rates ACE Securities Corp. Home Equity Loan Trust Series 2004-OP1.

Business Editors

NEW YORK--(BUSINESS WIRE)--April 21, 2004

Fitch has rated the ACE Securities Corp. Home Equity Loan Trust, series 2004-OP1 asset-backed pass-through certificates as follows:

-- $1.234 billion classes A-1, A-2A, A-2B and A-2C 'AAA';

-- $103.7 million class M-1 'AA';

-- $82.8 million class M-2 'A+';

-- $22.4 million class M-3 'A';

-- $19.3 million class M-4 'A-';

-- $21.7 million class M-5 'BBB+';

-- $20.1 million class M-6 'BBB';

-- $27.9 million not-offered class B 'BB'.

The 'AAA' rating on the senior certificates reflects the 20.25% total credit enhancement provided by the 6.70% class M-1, 5.35% class M-2, 1.45% class M-3, 1.25% class M-4, 1.40% class M-5, 1.30% class M-6, 1.80% class B and 1% initial overcollateralization (OC). All certificates have the benefit of monthly excess cash flow to absorb losses. In addition, the ratings reflect the quality of the loans, the integrity of the transaction's legal structure, as well as the capabilities of Option One Mortgage Corporation as servicer, Wells Fargo Bank, N. A. as master servicer, and HSBC Bank USA as trustee.

The certificates are supported by two collateral groups, one conforming, the other non-conforming. The Group I mortgage pool consists of first- and second-lien, adjustable-rate and fixed-rate, conforming mortgage loans having a cut-off date pool balance of $1,325,807,653. Approximately 25.38% of the mortgage loans are fixed-rate mortgage loans and 74.62% are adjustable-rate mortgage loans. The weighted average loan rate is approximately 7.285%. The weighted average remaining term to maturity (WAM) is 354 months. The average principal balance of the loans is approximately $145,677. The weighted average original loan-to-value (OLTV) ratio is 77.06%. The properties are primarily located in New York (15.68%), California (15.31%) and Massachusetts (10.18%).

The Group II mortgage pool consists of first- and second-lien adjustable-rate and fixed-rate, conforming and non-conforming mortgage loans with a cut-off date pool balance of $221,687,406. Approximately 24.04% of the mortgage loans are fixed rate mortgage loans and 75.96% are adjustable-rate mortgage loans. The weighted average loan rate is approximately 7.122%. The WAM is 356 months. The average principal balance of the loans is approximately $223,026. The weighted average OLTV is 77.60%. The properties are primarily located in California (25.52%), New York (20.78%) and Massachusetts (8.36%).

Deutsche Bank AG New York Branch (the mortgage loan seller), is selling the mortgage loans to Ace Securities Corp. (the depositor) and the depositor is conveying the mortgage loans to the trust fund. For federal income tax purposes, multiple real estate mortgage investment conduit (REMIC) elections will be made with respect to the trust estate.