HttpClientFactory with dynamic configurations

Question

I am working on .net core web app which needs to call remote APIs at specific intervals(every 2 mins, 20 different API calls & I need to show API results to end users), hosted with 4 different domain names

I used HttpClient to call remote APIs. But with increased users, my CPU usage increased up to 40%. I suspect HttpClient might be the reason. After going through few blogs, I am trying to use HttpClientFactory.
I have a single method which gets call from Controller Action & I need to dynamically identify the BaseUrl based on few parameters. Currently I have created 4 NamedClients in StartUp.cs like this:

   services.AddHttpClient(ApiConfig.NamedHttpClients.TestUrl1, client =>
       {
           client.BaseAddress = new Uri(Configuration.GetSection("BaseUrls").GetSection("TestUrl1").Value);
           client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
           client.DefaultRequestHeaders.Add("Authorization", "Basic " + ApiConfig.GetEncodedCredentials(Configuration));
           var userAgent = "C# app";
           client.DefaultRequestHeaders.Add("User-Agent", userAgent);
       }).SetHandlerLifetime(TimeSpan.FromMinutes(5));
        services.AddHttpClient(ApiConfig.NamedHttpClients.TestUrl2, client =>
        {
            client.BaseAddress = new Uri(Configuration.GetSection("BaseUrls").GetSection("TestUrl2").Value);
            client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
            client.DefaultRequestHeaders.Add("Authorization", "Basic " + ApiConfig.GetEncodedCredentials(Configuration));
            var userAgent = "C# app";
            client.DefaultRequestHeaders.Add("User-Agent", userAgent);
        });

And then using in class like this:

  public class Service : IService
{
    private readonly IHttpClientFactory httpClientFactory;
    public Service(IHttpClientFactory clientFactory)
    {
        httpClientFactory = clientFactory;
    }
    public HttpResponseMessage GetApiClientResponse(string displayName, IConfiguration configuration, HttpRequest httpRequest)
    {
        var endPoint = ApiConfig.GetApiDetail(configuration).
                            SingleOrDefault(ep => ep.DisplayName.ToLower().Equals(displayName.ToLower()));
        var client = httpClientFactory.CreateClient(endPoint.NamedClient);
        HttpResponseMessage response = null;
        try
        {
            response = client.GetAsync(new Uri(endPoint.EndPointName,UriKind.Relative), HttpCompletionOption.ResponseHeadersRead).Result;
        }
        catch { ...}
        return response;
    }
}

here, based on the displayname parameter, I can decide which NamedClient is to be used.
Is there any other efficient way to achieve required functionality? Can I use TypedClient instead?